These files were mostly based on the score port, but many of them are
very ISA specific.
Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxxx>
---
arch/riscv/kernel/.gitignore | 1 +
arch/riscv/kernel/Makefile | 16 ++
arch/riscv/kernel/asm-offsets.c | 316 +++++++++++++++++++++++++++
arch/riscv/kernel/cacheinfo.c | 103 +++++++++
arch/riscv/kernel/cpu.c | 89 ++++++++
arch/riscv/kernel/entry.S | 437 +++++++++++++++++++++++++++++++++++++
arch/riscv/kernel/head.S | 147 +++++++++++++
arch/riscv/kernel/irq.c | 20 ++
arch/riscv/kernel/module.c | 215 ++++++++++++++++++
arch/riscv/kernel/process.c | 132 +++++++++++
arch/riscv/kernel/ptrace.c | 147 +++++++++++++
arch/riscv/kernel/reset.c | 36 +++
arch/riscv/kernel/riscv_ksyms.c | 16 ++
arch/riscv/kernel/setup.c | 240 ++++++++++++++++++++
arch/riscv/kernel/signal.c | 257 ++++++++++++++++++++++
arch/riscv/kernel/smp.c | 110 ++++++++++
arch/riscv/kernel/smpboot.c | 103 +++++++++
arch/riscv/kernel/stacktrace.c | 177 +++++++++++++++
arch/riscv/kernel/sys_riscv.c | 85 ++++++++
arch/riscv/kernel/syscall_table.c | 25 +++
arch/riscv/kernel/traps.c | 183 ++++++++++++++++
arch/riscv/kernel/vdso.c | 125 +++++++++++
arch/riscv/kernel/vdso/.gitignore | 1 +
arch/riscv/kernel/vdso/Makefile | 61 ++++++
arch/riscv/kernel/vdso/sigreturn.S | 24 ++
arch/riscv/kernel/vdso/vdso.S | 27 +++
arch/riscv/kernel/vdso/vdso.lds.S | 76 +++++++
arch/riscv/kernel/vmlinux.lds.S | 92 ++++++++
28 files changed, 3261 insertions(+)
create mode 100644 arch/riscv/kernel/.gitignore
create mode 100644 arch/riscv/kernel/Makefile
create mode 100644 arch/riscv/kernel/asm-offsets.c
create mode 100644 arch/riscv/kernel/cacheinfo.c
create mode 100644 arch/riscv/kernel/cpu.c
create mode 100644 arch/riscv/kernel/entry.S
create mode 100644 arch/riscv/kernel/head.S
create mode 100644 arch/riscv/kernel/irq.c
create mode 100644 arch/riscv/kernel/module.c
create mode 100644 arch/riscv/kernel/process.c
create mode 100644 arch/riscv/kernel/ptrace.c
create mode 100644 arch/riscv/kernel/reset.c
create mode 100644 arch/riscv/kernel/riscv_ksyms.c
create mode 100644 arch/riscv/kernel/setup.c
create mode 100644 arch/riscv/kernel/signal.c
create mode 100644 arch/riscv/kernel/smp.c
create mode 100644 arch/riscv/kernel/smpboot.c
create mode 100644 arch/riscv/kernel/stacktrace.c
create mode 100644 arch/riscv/kernel/sys_riscv.c
create mode 100644 arch/riscv/kernel/syscall_table.c
create mode 100644 arch/riscv/kernel/traps.c
create mode 100644 arch/riscv/kernel/vdso.c
create mode 100644 arch/riscv/kernel/vdso/.gitignore
create mode 100644 arch/riscv/kernel/vdso/Makefile
create mode 100644 arch/riscv/kernel/vdso/sigreturn.S
create mode 100644 arch/riscv/kernel/vdso/vdso.S
create mode 100644 arch/riscv/kernel/vdso/vdso.lds.S
create mode 100644 arch/riscv/kernel/vmlinux.lds.S
diff --git a/arch/riscv/kernel/.gitignore b/arch/riscv/kernel/.gitignore
new file mode 100644
index 000000000000..b51634f6a7cd
--- /dev/null
+++ b/arch/riscv/kernel/.gitignore
@@ -0,0 +1 @@
+/vmlinux.lds
diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile
new file mode 100644
index 000000000000..b6de129d4a23
--- /dev/null
+++ b/arch/riscv/kernel/Makefile
@@ -0,0 +1,16 @@
+#
+# Makefile for the RISC-V Linux kernel
+#
+
+extra-y := head.o vmlinux.lds
+
+obj-y := cpu.o entry.o irq.o process.o ptrace.o reset.o setup.o \
+ signal.o syscall_table.o sys_riscv.o traps.o \
+ riscv_ksyms.o stacktrace.o vdso.o cacheinfo.o vdso/
+
+CFLAGS_setup.o := -mcmodel=medany
+
+obj-$(CONFIG_SMP) += smpboot.o smp.o
+obj-$(CONFIG_MODULES) += module.o
+
+clean:
diff --git a/arch/riscv/kernel/asm-offsets.c b/arch/riscv/kernel/asm-offsets.c
new file mode 100644
index 000000000000..2ead5037528c
--- /dev/null
+++ b/arch/riscv/kernel/asm-offsets.c
@@ -0,0 +1,316 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kbuild.h>
+#include <linux/sched.h>
+#include <asm/thread_info.h>
+#include <asm/ptrace.h>
+
+void asm_offsets(void)
+{
+ OFFSET(TASK_THREAD_RA, task_struct, thread.ra);
+ OFFSET(TASK_THREAD_SP, task_struct, thread.sp);
+ OFFSET(TASK_THREAD_S0, task_struct, thread.s[0]);
+ OFFSET(TASK_THREAD_S1, task_struct, thread.s[1]);
+ OFFSET(TASK_THREAD_S2, task_struct, thread.s[2]);
+ OFFSET(TASK_THREAD_S3, task_struct, thread.s[3]);
+ OFFSET(TASK_THREAD_S4, task_struct, thread.s[4]);
+ OFFSET(TASK_THREAD_S5, task_struct, thread.s[5]);
+ OFFSET(TASK_THREAD_S6, task_struct, thread.s[6]);
+ OFFSET(TASK_THREAD_S7, task_struct, thread.s[7]);
+ OFFSET(TASK_THREAD_S8, task_struct, thread.s[8]);
+ OFFSET(TASK_THREAD_S9, task_struct, thread.s[9]);
+ OFFSET(TASK_THREAD_S10, task_struct, thread.s[10]);
+ OFFSET(TASK_THREAD_S11, task_struct, thread.s[11]);
+ OFFSET(TASK_THREAD_SP, task_struct, thread.sp);
+ OFFSET(TASK_STACK, task_struct, stack);
+ OFFSET(TASK_TI, task_struct, thread_info);
+ OFFSET(TASK_TI_FLAGS, task_struct, thread_info.flags);
+ OFFSET(TASK_TI_KERNEL_SP, task_struct, thread_info.kernel_sp);
+ OFFSET(TASK_TI_USER_SP, task_struct, thread_info.user_sp);
+
+ OFFSET(TASK_THREAD_F0, task_struct, thread.fstate.f[0]);
+ OFFSET(TASK_THREAD_F1, task_struct, thread.fstate.f[1]);
+ OFFSET(TASK_THREAD_F2, task_struct, thread.fstate.f[2]);
+ OFFSET(TASK_THREAD_F3, task_struct, thread.fstate.f[3]);
+ OFFSET(TASK_THREAD_F4, task_struct, thread.fstate.f[4]);
+ OFFSET(TASK_THREAD_F5, task_struct, thread.fstate.f[5]);
+ OFFSET(TASK_THREAD_F6, task_struct, thread.fstate.f[6]);
+ OFFSET(TASK_THREAD_F7, task_struct, thread.fstate.f[7]);
+ OFFSET(TASK_THREAD_F8, task_struct, thread.fstate.f[8]);
+ OFFSET(TASK_THREAD_F9, task_struct, thread.fstate.f[9]);
+ OFFSET(TASK_THREAD_F10, task_struct, thread.fstate.f[10]);
+ OFFSET(TASK_THREAD_F11, task_struct, thread.fstate.f[11]);
+ OFFSET(TASK_THREAD_F12, task_struct, thread.fstate.f[12]);
+ OFFSET(TASK_THREAD_F13, task_struct, thread.fstate.f[13]);
+ OFFSET(TASK_THREAD_F14, task_struct, thread.fstate.f[14]);
+ OFFSET(TASK_THREAD_F15, task_struct, thread.fstate.f[15]);
+ OFFSET(TASK_THREAD_F16, task_struct, thread.fstate.f[16]);
+ OFFSET(TASK_THREAD_F17, task_struct, thread.fstate.f[17]);
+ OFFSET(TASK_THREAD_F18, task_struct, thread.fstate.f[18]);
+ OFFSET(TASK_THREAD_F19, task_struct, thread.fstate.f[19]);
+ OFFSET(TASK_THREAD_F20, task_struct, thread.fstate.f[20]);
+ OFFSET(TASK_THREAD_F21, task_struct, thread.fstate.f[21]);
+ OFFSET(TASK_THREAD_F22, task_struct, thread.fstate.f[22]);
+ OFFSET(TASK_THREAD_F23, task_struct, thread.fstate.f[23]);
+ OFFSET(TASK_THREAD_F24, task_struct, thread.fstate.f[24]);
+ OFFSET(TASK_THREAD_F25, task_struct, thread.fstate.f[25]);
+ OFFSET(TASK_THREAD_F26, task_struct, thread.fstate.f[26]);
+ OFFSET(TASK_THREAD_F27, task_struct, thread.fstate.f[27]);
+ OFFSET(TASK_THREAD_F28, task_struct, thread.fstate.f[28]);
+ OFFSET(TASK_THREAD_F29, task_struct, thread.fstate.f[29]);
+ OFFSET(TASK_THREAD_F30, task_struct, thread.fstate.f[30]);
+ OFFSET(TASK_THREAD_F31, task_struct, thread.fstate.f[31]);
+ OFFSET(TASK_THREAD_FCSR, task_struct, thread.fstate.fcsr);
+
+ DEFINE(PT_SIZE, sizeof(struct pt_regs));
+ OFFSET(PT_SEPC, pt_regs, sepc);
+ OFFSET(PT_RA, pt_regs, ra);
+ OFFSET(PT_FP, pt_regs, s0);
+ OFFSET(PT_S0, pt_regs, s0);
+ OFFSET(PT_S1, pt_regs, s1);
+ OFFSET(PT_S2, pt_regs, s2);
+ OFFSET(PT_S3, pt_regs, s3);
+ OFFSET(PT_S4, pt_regs, s4);
+ OFFSET(PT_S5, pt_regs, s5);
+ OFFSET(PT_S6, pt_regs, s6);
+ OFFSET(PT_S7, pt_regs, s7);
+ OFFSET(PT_S8, pt_regs, s8);
+ OFFSET(PT_S9, pt_regs, s9);
+ OFFSET(PT_S10, pt_regs, s10);
+ OFFSET(PT_S11, pt_regs, s11);
+ OFFSET(PT_SP, pt_regs, sp);
+ OFFSET(PT_TP, pt_regs, tp);
+ OFFSET(PT_A0, pt_regs, a0);
+ OFFSET(PT_A1, pt_regs, a1);
+ OFFSET(PT_A2, pt_regs, a2);
+ OFFSET(PT_A3, pt_regs, a3);
+ OFFSET(PT_A4, pt_regs, a4);
+ OFFSET(PT_A5, pt_regs, a5);
+ OFFSET(PT_A6, pt_regs, a6);
+ OFFSET(PT_A7, pt_regs, a7);
+ OFFSET(PT_T0, pt_regs, t0);
+ OFFSET(PT_T1, pt_regs, t1);
+ OFFSET(PT_T2, pt_regs, t2);
+ OFFSET(PT_T3, pt_regs, t3);
+ OFFSET(PT_T4, pt_regs, t4);
+ OFFSET(PT_T5, pt_regs, t5);
+ OFFSET(PT_T6, pt_regs, t6);
+ OFFSET(PT_GP, pt_regs, gp);
+ OFFSET(PT_SSTATUS, pt_regs, sstatus);
+ OFFSET(PT_SBADADDR, pt_regs, sbadaddr);
+ OFFSET(PT_SCAUSE, pt_regs, scause);
+
+ /* THREAD_{F,X}* might be larger than a S-type offset can handle, but
+ * these are used in performance-sensitive assembly so we can't resort
+ * to loading the long immediate every time.
+ */
+ DEFINE(TASK_THREAD_RA_RA,
+ offsetof(struct task_struct, thread.ra)
+ - offsetof(struct task_struct, thread.ra)
+ );
+ DEFINE(TASK_THREAD_SP_RA,
+ offsetof(struct task_struct, thread.sp)
+ - offsetof(struct task_struct, thread.ra)
+ );
+ DEFINE(TASK_THREAD_S0_RA,
+ offsetof(struct task_struct, thread.s[0])
+ - offsetof(struct task_struct, thread.ra)
+ );
+ DEFINE(TASK_THREAD_S1_RA,
+ offsetof(struct task_struct, thread.s[1])
+ - offsetof(struct task_struct, thread.ra)
+ );
+ DEFINE(TASK_THREAD_S2_RA,
+ offsetof(struct task_struct, thread.s[2])
+ - offsetof(struct task_struct, thread.ra)
+ );
+ DEFINE(TASK_THREAD_S3_RA,
+ offsetof(struct task_struct, thread.s[3])
+ - offsetof(struct task_struct, thread.ra)
+ );
+ DEFINE(TASK_THREAD_S4_RA,
+ offsetof(struct task_struct, thread.s[4])
+ - offsetof(struct task_struct, thread.ra)
+ );
+ DEFINE(TASK_THREAD_S5_RA,
+ offsetof(struct task_struct, thread.s[5])
+ - offsetof(struct task_struct, thread.ra)
+ );
+ DEFINE(TASK_THREAD_S6_RA,
+ offsetof(struct task_struct, thread.s[6])
+ - offsetof(struct task_struct, thread.ra)
+ );
+ DEFINE(TASK_THREAD_S7_RA,
+ offsetof(struct task_struct, thread.s[7])
+ - offsetof(struct task_struct, thread.ra)
+ );
+ DEFINE(TASK_THREAD_S8_RA,
+ offsetof(struct task_struct, thread.s[8])
+ - offsetof(struct task_struct, thread.ra)
+ );
+ DEFINE(TASK_THREAD_S9_RA,
+ offsetof(struct task_struct, thread.s[9])
+ - offsetof(struct task_struct, thread.ra)
+ );
+ DEFINE(TASK_THREAD_S10_RA,
+ offsetof(struct task_struct, thread.s[10])
+ - offsetof(struct task_struct, thread.ra)
+ );
+ DEFINE(TASK_THREAD_S11_RA,
+ offsetof(struct task_struct, thread.s[11])
+ - offsetof(struct task_struct, thread.ra)
+ );
+
+ DEFINE(TASK_THREAD_F0_F0,
+ offsetof(struct task_struct, thread.fstate.f[0])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F1_F0,
+ offsetof(struct task_struct, thread.fstate.f[1])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F2_F0,
+ offsetof(struct task_struct, thread.fstate.f[2])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F3_F0,
+ offsetof(struct task_struct, thread.fstate.f[3])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F4_F0,
+ offsetof(struct task_struct, thread.fstate.f[4])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F5_F0,
+ offsetof(struct task_struct, thread.fstate.f[5])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F6_F0,
+ offsetof(struct task_struct, thread.fstate.f[6])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F7_F0,
+ offsetof(struct task_struct, thread.fstate.f[7])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F8_F0,
+ offsetof(struct task_struct, thread.fstate.f[8])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F9_F0,
+ offsetof(struct task_struct, thread.fstate.f[9])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F10_F0,
+ offsetof(struct task_struct, thread.fstate.f[10])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F11_F0,
+ offsetof(struct task_struct, thread.fstate.f[11])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F12_F0,
+ offsetof(struct task_struct, thread.fstate.f[12])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F13_F0,
+ offsetof(struct task_struct, thread.fstate.f[13])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F14_F0,
+ offsetof(struct task_struct, thread.fstate.f[14])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F15_F0,
+ offsetof(struct task_struct, thread.fstate.f[15])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F16_F0,
+ offsetof(struct task_struct, thread.fstate.f[16])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F17_F0,
+ offsetof(struct task_struct, thread.fstate.f[17])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F18_F0,
+ offsetof(struct task_struct, thread.fstate.f[18])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F19_F0,
+ offsetof(struct task_struct, thread.fstate.f[19])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F20_F0,
+ offsetof(struct task_struct, thread.fstate.f[20])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F21_F0,
+ offsetof(struct task_struct, thread.fstate.f[21])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F22_F0,
+ offsetof(struct task_struct, thread.fstate.f[22])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F23_F0,
+ offsetof(struct task_struct, thread.fstate.f[23])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F24_F0,
+ offsetof(struct task_struct, thread.fstate.f[24])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F25_F0,
+ offsetof(struct task_struct, thread.fstate.f[25])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F26_F0,
+ offsetof(struct task_struct, thread.fstate.f[26])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F27_F0,
+ offsetof(struct task_struct, thread.fstate.f[27])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F28_F0,
+ offsetof(struct task_struct, thread.fstate.f[28])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F29_F0,
+ offsetof(struct task_struct, thread.fstate.f[29])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F30_F0,
+ offsetof(struct task_struct, thread.fstate.f[30])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_F31_F0,
+ offsetof(struct task_struct, thread.fstate.f[31])
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+ DEFINE(TASK_THREAD_FCSR_F0,
+ offsetof(struct task_struct, thread.fstate.fcsr)
+ - offsetof(struct task_struct, thread.fstate.f[0])
+ );
+
+ /* The assembler needs access to THREAD_SIZE as well. */
+ DEFINE(ASM_THREAD_SIZE, THREAD_SIZE);
+
+ /* We allocate a pt_regs on the stack when entering the kernel. This
+ * ensures the alignment is sane.
+ */
+ DEFINE(PT_SIZE_ON_STACK, ALIGN(sizeof(struct pt_regs), STACK_ALIGN));
+}
diff --git a/arch/riscv/kernel/cacheinfo.c b/arch/riscv/kernel/cacheinfo.c
new file mode 100644
index 000000000000..76ed95850a22
--- /dev/null
+++ b/arch/riscv/kernel/cacheinfo.c
@@ -0,0 +1,103 @@
+/*
+ * Copyright (C) 2017 SiFive
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/cacheinfo.h>
+#include <linux/cpu.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+
+static void ci_leaf_init(struct cacheinfo *this_leaf,
+ struct device_node *node,
+ enum cache_type type, unsigned int level)
+{
+ this_leaf->of_node = node;
+ this_leaf->level = level;
+ this_leaf->type = type;
+ this_leaf->physical_line_partition = 1; // not a sector cache
+ this_leaf->attributes =
+ CACHE_WRITE_BACK
+ | CACHE_READ_ALLOCATE
+ | CACHE_WRITE_ALLOCATE; // TODO: add to DTS
+}
+
+static int __init_cache_level(unsigned int cpu)
+{
+ struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
+ struct device_node *np = of_cpu_device_node_get(cpu);
+ int levels = 0, leaves = 0, level;
+
+ if (of_property_read_bool(np, "cache-size"))
+ ++leaves;
+ if (of_property_read_bool(np, "i-cache-size"))
+ ++leaves;
+ if (of_property_read_bool(np, "d-cache-size"))
+ ++leaves;
+ if (leaves > 0)
+ levels = 1;
+
+ while ((np = of_find_next_cache_node(np))) {
+ if (!of_device_is_compatible(np, "cache"))
+ break;
+ if (of_property_read_u32(np, "cache-level", &level))
+ break;
+ if (level <= levels)
+ break;
+ if (of_property_read_bool(np, "cache-size"))
+ ++leaves;
+ if (of_property_read_bool(np, "i-cache-size"))
+ ++leaves;
+ if (of_property_read_bool(np, "d-cache-size"))
+ ++leaves;
+ levels = level;
+ }
+
+ this_cpu_ci->num_levels = levels;
+ this_cpu_ci->num_leaves = leaves;
+ return 0;
+}
+
+static int __populate_cache_leaves(unsigned int cpu)
+{
+ struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
+ struct cacheinfo *this_leaf = this_cpu_ci->info_list;
+ struct device_node *np = of_cpu_device_node_get(cpu);
+ int levels = 1, level = 1;
+
+ if (of_property_read_bool(np, "cache-size"))
+ ci_leaf_init(this_leaf++, np, CACHE_TYPE_UNIFIED, level);
+ if (of_property_read_bool(np, "i-cache-size"))
+ ci_leaf_init(this_leaf++, np, CACHE_TYPE_INST, level);
+ if (of_property_read_bool(np, "d-cache-size"))
+ ci_leaf_init(this_leaf++, np, CACHE_TYPE_DATA, level);
+
+ while ((np = of_find_next_cache_node(np))) {
+ if (!of_device_is_compatible(np, "cache"))
+ break;
+ if (of_property_read_u32(np, "cache-level", &level))
+ break;
+ if (level <= levels)
+ break;
+ if (of_property_read_bool(np, "cache-size"))
+ ci_leaf_init(this_leaf++, np, CACHE_TYPE_UNIFIED, level);
+ if (of_property_read_bool(np, "i-cache-size"))
+ ci_leaf_init(this_leaf++, np, CACHE_TYPE_INST, level);
+ if (of_property_read_bool(np, "d-cache-size"))
+ ci_leaf_init(this_leaf++, np, CACHE_TYPE_DATA, level);
+ levels = level;
+ }
+
+ return 0;
+}
+
+DEFINE_SMP_CALL_CACHE_FUNCTION(init_cache_level)
+DEFINE_SMP_CALL_CACHE_FUNCTION(populate_cache_leaves)
diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
new file mode 100644
index 000000000000..20004bd7a216
--- /dev/null
+++ b/arch/riscv/kernel/cpu.c
@@ -0,0 +1,89 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/init.h>
+#include <linux/seq_file.h>
+#include <linux/of.h>
+
+/* Return -1 if not a valid hart */
+int riscv_of_processor_hart(struct device_node *node)
+{
+ const char *isa, *status;
+ u32 hart;
+
+ if (!of_device_is_compatible(node, "riscv"))
+ return -(ENODEV);
+ if (of_property_read_u32(node, "reg", &hart)
+ || hart >= NR_CPUS)
+ return -(ENODEV);
+ if (of_property_read_string(node, "status", &status)
+ || strcmp(status, "okay"))
+ return -(ENODEV);
+ if (of_property_read_string(node, "riscv,isa", &isa)
+ || isa[0] != 'r'
+ || isa[1] != 'v')
+ return -(ENODEV);
+
+ return hart;
+}
+
+#ifdef CONFIG_PROC_FS
+
+static void *c_start(struct seq_file *m, loff_t *pos)
+{
+ *pos = cpumask_next(*pos - 1, cpu_online_mask);
+ if ((*pos) < nr_cpu_ids)
+ return (void *)(uintptr_t)(1 + *pos);
+ return NULL;
+}
+
+static void *c_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ (*pos)++;
+ return c_start(m, pos);
+}
+
+static void c_stop(struct seq_file *m, void *v)
+{
+}
+
+static int c_show(struct seq_file *m, void *v)
+{
+ unsigned long hart_id = (unsigned long)v - 1;
+ struct device_node *node = of_get_cpu_node(hart_id, NULL);
+ const char *compat, *isa, *mmu;
+
+ seq_printf(m, "hart\t: %lu\n", hart_id);
+ if (!of_property_read_string(node, "riscv,isa", &isa)
+ && isa[0] == 'r'
+ && isa[1] == 'v')
+ seq_printf(m, "isa\t: %s\n", isa);
+ if (!of_property_read_string(node, "mmu-type", &mmu)
+ && !strncmp(mmu, "riscv,", 6))
+ seq_printf(m, "mmu\t: %s\n", mmu+6);
+ if (!of_property_read_string(node, "compatible", &compat)
+ && strcmp(compat, "riscv"))
+ seq_printf(m, "uarch\t: %s\n", compat);
+ seq_puts(m, "\n");
+
+ return 0;
+}
+
+const struct seq_operations cpuinfo_op = {
+ .start = c_start,
+ .next = c_next,
+ .stop = c_stop,
+ .show = c_show
+};
+
+#endif /* CONFIG_PROC_FS */
diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S
new file mode 100644
index 000000000000..0be9ca33e8fc
--- /dev/null
+++ b/arch/riscv/kernel/entry.S
@@ -0,0 +1,437 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/init.h>
+#include <linux/linkage.h>
+
+#include <asm/asm.h>
+#include <asm/csr.h>
+#include <asm/unistd.h>
+#include <asm/thread_info.h>
+#include <asm/asm-offsets.h>
+
+ .text
+ .altmacro
+
+/* Prepares to enter a system call or exception by saving all registers to the
+ * stack.
+ */
+ .macro SAVE_ALL
+ LOCAL _restore_kernel_tpsp
+ LOCAL _save_context
+
+ /* If coming from userspace, preserve the user thread pointer and load
+ the kernel thread pointer. If we came from the kernel, sscratch
+ will contain 0, and we should continue on the current TP. */
+ csrrw tp, sscratch, tp
+ bnez tp, _save_context
+
+_restore_kernel_tpsp:
+ csrr tp, sscratch
+ REG_S sp, TASK_TI_KERNEL_SP(tp)
+_save_context:
+ REG_S sp, TASK_TI_USER_SP(tp)
+ REG_L sp, TASK_TI_KERNEL_SP(tp)
+ addi sp, sp, -(PT_SIZE_ON_STACK)
+ REG_S x1, PT_RA(sp)
+ REG_S x3, PT_GP(sp)
+ REG_S x5, PT_T0(sp)
+ REG_S x6, PT_T1(sp)
+ REG_S x7, PT_T2(sp)
+ REG_S x8, PT_S0(sp)
+ REG_S x9, PT_S1(sp)
+ REG_S x10, PT_A0(sp)
+ REG_S x11, PT_A1(sp)
+ REG_S x12, PT_A2(sp)
+ REG_S x13, PT_A3(sp)
+ REG_S x14, PT_A4(sp)
+ REG_S x15, PT_A5(sp)
+ REG_S x16, PT_A6(sp)
+ REG_S x17, PT_A7(sp)
+ REG_S x18, PT_S2(sp)
+ REG_S x19, PT_S3(sp)
+ REG_S x20, PT_S4(sp)
+ REG_S x21, PT_S5(sp)
+ REG_S x22, PT_S6(sp)
+ REG_S x23, PT_S7(sp)
+ REG_S x24, PT_S8(sp)
+ REG_S x25, PT_S9(sp)
+ REG_S x26, PT_S10(sp)
+ REG_S x27, PT_S11(sp)
+ REG_S x28, PT_T3(sp)
+ REG_S x29, PT_T4(sp)
+ REG_S x30, PT_T5(sp)
+ REG_S x31, PT_T6(sp)
+
+ /* Disable FPU to detect illegal usage of
+ floating point in kernel space */
+ li t0, SR_FS
+
+ REG_L s0, TASK_TI_USER_SP(tp)
+ csrrc s1, sstatus, t0
+ csrr s2, sepc
+ csrr s3, sbadaddr
+ csrr s4, scause
+ csrr s5, sscratch
+ REG_S s0, PT_SP(sp)
+ REG_S s1, PT_SSTATUS(sp)
+ REG_S s2, PT_SEPC(sp)
+ REG_S s3, PT_SBADADDR(sp)
+ REG_S s4, PT_SCAUSE(sp)
+ REG_S s5, PT_TP(sp)
+ .endm
+
+/* Prepares to return from a system call or exception by restoring all
+ * registers from the stack.
+ */
+ .macro RESTORE_ALL
+ REG_L a0, PT_SSTATUS(sp)
+ REG_L a2, PT_SEPC(sp)
+ csrw sstatus, a0
+ csrw sepc, a2
+
+ REG_L x1, PT_RA(sp)
+ REG_L x3, PT_GP(sp)
+ REG_L x4, PT_TP(sp)
+ REG_L x5, PT_T0(sp)
+ REG_L x6, PT_T1(sp)
+ REG_L x7, PT_T2(sp)
+ REG_L x8, PT_S0(sp)
+ REG_L x9, PT_S1(sp)
+ REG_L x10, PT_A0(sp)
+ REG_L x11, PT_A1(sp)
+ REG_L x12, PT_A2(sp)
+ REG_L x13, PT_A3(sp)
+ REG_L x14, PT_A4(sp)
+ REG_L x15, PT_A5(sp)
+ REG_L x16, PT_A6(sp)
+ REG_L x17, PT_A7(sp)
+ REG_L x18, PT_S2(sp)
+ REG_L x19, PT_S3(sp)
+ REG_L x20, PT_S4(sp)
+ REG_L x21, PT_S5(sp)
+ REG_L x22, PT_S6(sp)
+ REG_L x23, PT_S7(sp)
+ REG_L x24, PT_S8(sp)
+ REG_L x25, PT_S9(sp)
+ REG_L x26, PT_S10(sp)
+ REG_L x27, PT_S11(sp)
+ REG_L x28, PT_T3(sp)
+ REG_L x29, PT_T4(sp)
+ REG_L x30, PT_T5(sp)
+ REG_L x31, PT_T6(sp)
+
+ REG_L x2, PT_SP(sp)
+ .endm
+
+ENTRY(handle_exception)
+ SAVE_ALL
+
+ /* Set sscratch register to 0, so that if a recursive exception
+ occurs, the exception vector knows it came from the kernel */
+ csrw sscratch, x0
+
+ la gp, __global_pointer$
+
+ la ra, ret_from_exception
+ /* MSB of cause differentiates between
+ interrupts and exceptions */
+ bge s4, zero, 1f
+
+ /* Handle interrupts */
+ slli a0, s4, 1
+ srli a0, a0, 1
+ move a1, sp /* pt_regs */
+ tail do_IRQ
+1:
+ /* Handle syscalls */
+ li t0, EXC_SYSCALL
+ beq s4, t0, handle_syscall
+
+ /* Handle other exceptions */
+ slli t0, s4, RISCV_LGPTR
+ la t1, excp_vect_table
+ la t2, excp_vect_table_end
+ move a0, sp /* pt_regs */
+ add t0, t1, t0
+ /* Check if exception code lies within bounds */
+ bgeu t0, t2, 1f
+ REG_L t0, 0(t0)
+ jr t0
+1:
+ tail do_trap_unknown
+
+handle_syscall:
+ /* Advance SEPC to avoid executing the original
+ scall instruction on sret */
+ addi s2, s2, 0x4
+ REG_S s2, PT_SEPC(sp)
+ /* System calls run with interrupts enabled */
+ csrs sstatus, SR_IE
+ /* Trace syscalls, but only if requested by the user. */
+ REG_L t0, TASK_TI_FLAGS(tp)
+ andi t0, t0, _TIF_SYSCALL_TRACE
+ bnez t0, handle_syscall_trace_enter
+check_syscall_nr:
+ /* Check to make sure we don't jump to a bogus syscall number. */
+ li t0, __NR_syscalls
+ la s0, sys_ni_syscall
+ /* Syscall number held in a7 */
+ bgeu a7, t0, 1f
+ la s0, sys_call_table
+ slli t0, a7, RISCV_LGPTR
+ add s0, s0, t0
+ REG_L s0, 0(s0)
+1:
+ jalr s0
+
+ret_from_syscall:
+ /* Set user a0 to kernel a0 */
+ REG_S a0, PT_A0(sp)
+ /* Trace syscalls, but only if requested by the user. */
+ REG_L t0, TASK_TI_FLAGS(tp)
+ andi t0, t0, _TIF_SYSCALL_TRACE
+ bnez t0, handle_syscall_trace_exit
+
+ret_from_exception:
+ REG_L s0, PT_SSTATUS(sp)
+ csrc sstatus, SR_IE
+ andi s0, s0, SR_PS
+ bnez s0, restore_all
+
+resume_userspace:
+ /* Interrupts must be disabled here so flags are checked atomically */
+ REG_L s0, TASK_TI_FLAGS(tp) /* current_thread_info->flags */
+ andi s1, s0, _TIF_WORK_MASK
+ bnez s1, work_pending
+
+ /* Save unwound kernel stack pointer in thread_info */
+ addi s0, sp, PT_SIZE_ON_STACK
+ REG_S s0, TASK_TI_KERNEL_SP(tp)
+
+ /* Save TP into sscratch, so we can find the kernel data structures
+ * again. */
+ csrw sscratch, tp
+
+restore_all:
+ RESTORE_ALL
+ sret
+
+work_pending:
+ /* Enter slow path for supplementary processing */
+ la ra, ret_from_exception
+ andi s1, s0, _TIF_NEED_RESCHED
+ bnez s1, work_resched
+work_notifysig:
+ /* Handle pending signals and notify-resume requests */
+ csrs sstatus, SR_IE /* Enable interrupts for do_notify_resume() */
+ move a0, sp /* pt_regs */
+ move a1, s0 /* current_thread_info->flags */
+ tail do_notify_resume
+work_resched:
+ tail schedule
+
+/* Slow paths for ptrace. */
+handle_syscall_trace_enter:
+ move a0, sp
+ call do_syscall_trace_enter
+ REG_L a0, PT_A0(sp)
+ REG_L a1, PT_A1(sp)
+ REG_L a2, PT_A2(sp)
+ REG_L a3, PT_A3(sp)
+ REG_L a4, PT_A4(sp)
+ REG_L a5, PT_A5(sp)
+ REG_L a6, PT_A6(sp)
+ REG_L a7, PT_A7(sp)
+ j check_syscall_nr
+handle_syscall_trace_exit:
+ move a0, sp
+ call do_syscall_trace_exit
+ j ret_from_exception
+
+END(handle_exception)
+
+ENTRY(ret_from_fork)
+ la ra, ret_from_exception
+ tail schedule_tail
+ENDPROC(ret_from_fork)
+
+ENTRY(ret_from_kernel_thread)
+ call schedule_tail
+ /* Call fn(arg) */
+ la ra, ret_from_exception
+ move a0, s1
+ jr s0
+ENDPROC(ret_from_kernel_thread)
+
+
+/*
+ * Integer register context switch
+ * The callee-saved registers must be saved and restored.
+ *
+ * a0: previous task_struct (must be preserved across the switch)
+ * a1: next task_struct
+ */
+ENTRY(__switch_to)
+ /* Save context into prev->thread */
+ li a2, TASK_THREAD_RA
+ add a0, a0, a2
+ add a2, a1, a2
+ REG_S ra, TASK_THREAD_RA_RA(a0)
+ REG_S sp, TASK_THREAD_SP_RA(a0)
+ REG_S s0, TASK_THREAD_S0_RA(a0)
+ REG_S s1, TASK_THREAD_S1_RA(a0)
+ REG_S s2, TASK_THREAD_S2_RA(a0)
+ REG_S s3, TASK_THREAD_S3_RA(a0)
+ REG_S s4, TASK_THREAD_S4_RA(a0)
+ REG_S s5, TASK_THREAD_S5_RA(a0)
+ REG_S s6, TASK_THREAD_S6_RA(a0)
+ REG_S s7, TASK_THREAD_S7_RA(a0)
+ REG_S s8, TASK_THREAD_S8_RA(a0)
+ REG_S s9, TASK_THREAD_S9_RA(a0)
+ REG_S s10, TASK_THREAD_S10_RA(a0)
+ REG_S s11, TASK_THREAD_S11_RA(a0)
+ /* Restore context from next->thread */
+ REG_L ra, TASK_THREAD_RA_RA(a2)
+ REG_L sp, TASK_THREAD_SP_RA(a2)
+ REG_L s0, TASK_THREAD_S0_RA(a2)
+ REG_L s1, TASK_THREAD_S1_RA(a2)
+ REG_L s2, TASK_THREAD_S2_RA(a2)
+ REG_L s3, TASK_THREAD_S3_RA(a2)
+ REG_L s4, TASK_THREAD_S4_RA(a2)
+ REG_L s5, TASK_THREAD_S5_RA(a2)
+ REG_L s6, TASK_THREAD_S6_RA(a2)
+ REG_L s7, TASK_THREAD_S7_RA(a2)
+ REG_L s8, TASK_THREAD_S8_RA(a2)
+ REG_L s9, TASK_THREAD_S9_RA(a2)
+ REG_L s10, TASK_THREAD_S10_RA(a2)
+ REG_L s11, TASK_THREAD_S11_RA(a2)
+#if TASK_TI != 0
+#error "TASK_TI != 0: tp will contain a 'struct thread_info', not a 'struct task_struct' so get_current() won't work."
+ addi tp, a1, TASK_TI
+#else
+ move tp, a1
+#endif
+ ret
+ENDPROC(__switch_to)
+
+ENTRY(__fstate_save)
+ li a2, TASK_THREAD_F0
+ add a0, a0, a2
+ li t1, SR_FS
+ csrs sstatus, t1
+ frcsr t0
+ fsd f0, TASK_THREAD_F0_F0(a0)
+ fsd f1, TASK_THREAD_F1_F0(a0)
+ fsd f2, TASK_THREAD_F2_F0(a0)
+ fsd f3, TASK_THREAD_F3_F0(a0)
+ fsd f4, TASK_THREAD_F4_F0(a0)
+ fsd f5, TASK_THREAD_F5_F0(a0)
+ fsd f6, TASK_THREAD_F6_F0(a0)
+ fsd f7, TASK_THREAD_F7_F0(a0)
+ fsd f8, TASK_THREAD_F8_F0(a0)
+ fsd f9, TASK_THREAD_F9_F0(a0)
+ fsd f10, TASK_THREAD_F10_F0(a0)
+ fsd f11, TASK_THREAD_F11_F0(a0)
+ fsd f12, TASK_THREAD_F12_F0(a0)
+ fsd f13, TASK_THREAD_F13_F0(a0)
+ fsd f14, TASK_THREAD_F14_F0(a0)
+ fsd f15, TASK_THREAD_F15_F0(a0)
+ fsd f16, TASK_THREAD_F16_F0(a0)
+ fsd f17, TASK_THREAD_F17_F0(a0)
+ fsd f18, TASK_THREAD_F18_F0(a0)
+ fsd f19, TASK_THREAD_F19_F0(a0)
+ fsd f20, TASK_THREAD_F20_F0(a0)
+ fsd f21, TASK_THREAD_F21_F0(a0)
+ fsd f22, TASK_THREAD_F22_F0(a0)
+ fsd f23, TASK_THREAD_F23_F0(a0)
+ fsd f24, TASK_THREAD_F24_F0(a0)
+ fsd f25, TASK_THREAD_F25_F0(a0)
+ fsd f26, TASK_THREAD_F26_F0(a0)
+ fsd f27, TASK_THREAD_F27_F0(a0)
+ fsd f28, TASK_THREAD_F28_F0(a0)
+ fsd f29, TASK_THREAD_F29_F0(a0)
+ fsd f30, TASK_THREAD_F30_F0(a0)
+ fsd f31, TASK_THREAD_F31_F0(a0)
+ sw t0, TASK_THREAD_FCSR_F0(a0)
+ csrc sstatus, t1
+ ret
+ENDPROC(__fstate_save)
+
+ENTRY(__fstate_restore)
+ li a2, TASK_THREAD_F0
+ add a0, a0, a2
+ li t1, SR_FS
+ lw t0, TASK_THREAD_FCSR_F0(a0)
+ csrs sstatus, t1
+ fld f0, TASK_THREAD_F0_F0(a0)
+ fld f1, TASK_THREAD_F1_F0(a0)
+ fld f2, TASK_THREAD_F2_F0(a0)
+ fld f3, TASK_THREAD_F3_F0(a0)
+ fld f4, TASK_THREAD_F4_F0(a0)
+ fld f5, TASK_THREAD_F5_F0(a0)
+ fld f6, TASK_THREAD_F6_F0(a0)
+ fld f7, TASK_THREAD_F7_F0(a0)
+ fld f8, TASK_THREAD_F8_F0(a0)
+ fld f9, TASK_THREAD_F9_F0(a0)
+ fld f10, TASK_THREAD_F10_F0(a0)
+ fld f11, TASK_THREAD_F11_F0(a0)
+ fld f12, TASK_THREAD_F12_F0(a0)
+ fld f13, TASK_THREAD_F13_F0(a0)
+ fld f14, TASK_THREAD_F14_F0(a0)
+ fld f15, TASK_THREAD_F15_F0(a0)
+ fld f16, TASK_THREAD_F16_F0(a0)
+ fld f17, TASK_THREAD_F17_F0(a0)
+ fld f18, TASK_THREAD_F18_F0(a0)
+ fld f19, TASK_THREAD_F19_F0(a0)
+ fld f20, TASK_THREAD_F20_F0(a0)
+ fld f21, TASK_THREAD_F21_F0(a0)
+ fld f22, TASK_THREAD_F22_F0(a0)
+ fld f23, TASK_THREAD_F23_F0(a0)
+ fld f24, TASK_THREAD_F24_F0(a0)
+ fld f25, TASK_THREAD_F25_F0(a0)
+ fld f26, TASK_THREAD_F26_F0(a0)
+ fld f27, TASK_THREAD_F27_F0(a0)
+ fld f28, TASK_THREAD_F28_F0(a0)
+ fld f29, TASK_THREAD_F29_F0(a0)
+ fld f30, TASK_THREAD_F30_F0(a0)
+ fld f31, TASK_THREAD_F31_F0(a0)
+ fscsr t0
+ csrc sstatus, t1
+ ret
+ENDPROC(__fstate_restore)
+
+
+ .section ".rodata"
+ /* Exception vector table */
+ENTRY(excp_vect_table)
+ RISCV_PTR do_trap_insn_misaligned
+ RISCV_PTR do_trap_insn_fault
+ RISCV_PTR do_trap_insn_illegal
+ RISCV_PTR do_trap_break
+ RISCV_PTR do_trap_load_misaligned
+ RISCV_PTR do_trap_load_fault
+ RISCV_PTR do_trap_store_misaligned
+ RISCV_PTR do_trap_store_fault
+ RISCV_PTR do_trap_ecall_u /* system call, gets intercepted */
+ RISCV_PTR do_trap_ecall_s
+ RISCV_PTR do_trap_unknown
+ RISCV_PTR do_trap_ecall_m
+ RISCV_PTR do_page_fault /* instruction page fault */
+ RISCV_PTR do_page_fault /* load page fault */
+ RISCV_PTR do_trap_unknown
+ RISCV_PTR do_page_fault /* store page fault */
+excp_vect_table_end:
+END(excp_vect_table)
+
diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
new file mode 100644
index 000000000000..608e57d4531f
--- /dev/null
+++ b/arch/riscv/kernel/head.S
@@ -0,0 +1,147 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <asm/thread_info.h>
+#include <asm/asm-offsets.h>
+#include <asm/asm.h>
+#include <linux/init.h>
+#include <linux/linkage.h>
+#include <asm/thread_info.h>
+#include <asm/page.h>
+#include <asm/csr.h>
+
+__INIT
+ENTRY(_start)
+ /* Mask all interrupts */
+ csrw sie, zero
+
+ /* Disable FPU to detect illegal usage of
+ floating point in kernel space */
+ li t0, SR_FS
+ csrc sstatus, t0
+
+#ifndef CONFIG_RV_PUM
+ /* Allow access to user memory */
+ li t0, SR_SUM
+ csrs sstatus, t0
+#endif
+
+#ifdef CONFIG_ISA_A
+ /* Pick one hart to run the main boot sequence */
+ la a3, hart_lottery
+ li a2, 1
+ amoadd.w a3, a2, (a3)
+ bnez a3, .Lsecondary_start
+#else
+ /* We don't have atomic support, so the boot hart must be picked
+ * staticly. Hart 0 is the only sane choice.
+ */
+ bnez a0, .Lsecondary_park
+#endif
+
+ /* Save hart ID and DTB physical address */
+ mv s0, a0
+ mv s1, a1
+
+ /* Initialize page tables and relocate to virtual addresses */
+ la sp, init_thread_union + THREAD_SIZE
+ call setup_vm
+ call relocate
+
+ /* Restore C environment */
+ la tp, init_task
+
+ la sp, init_thread_union
+ li a0, ASM_THREAD_SIZE
+ add sp, sp, a0
+
+ /* Start the kernel */
+ mv a0, s0
+ mv a1, s1
+ call sbi_save
+ tail start_kernel
+
+relocate:
+ /* Relocate return address */
+ li a1, PAGE_OFFSET
+ la a0, _start
+ sub a1, a1, a0
+ add ra, ra, a1
+
+ /* Point stvec to virtual address of intruction after sptbr write */
+ la a0, 1f
+ add a0, a0, a1
+ csrw stvec, a0
+
+ /* Compute sptbr for kernel page tables, but don't load it yet */
+ la a2, swapper_pg_dir
+ srl a2, a2, PAGE_SHIFT
+ li a1, SPTBR_MODE
+ or a2, a2, a1
+
+ /* Load trampoline page directory, which will cause us to trap to
+ stvec if VA != PA, or simply fall through if VA == PA */
+ la a0, trampoline_pg_dir
+ srl a0, a0, PAGE_SHIFT
+ or a0, a0, a1
+ sfence.vma
+ csrw sptbr, a0
+1:
+ /* Set trap vector to spin forever to help debug */
+ la a0, .Lsecondary_park
+ csrw stvec, a0
+
+ /* Load the global pointer */
+ la gp, __global_pointer$
+
+ /* Switch to kernel page tables */
+ csrw sptbr, a2
+
+ ret
+
+.Lsecondary_start:
+#ifdef CONFIG_SMP
+ li a1, CONFIG_NR_CPUS
+ bgeu a0, a1, .Lsecondary_park
+
+ la a1, __cpu_up_stack_pointer
+ slli a0, a0, LGREG
+ add a0, a0, a1
+
+.Lwait_for_cpu_up:
+ REG_L sp, (a0)
+ beqz sp, .Lwait_for_cpu_up
+ fence
+
+ /* Enable virtual memory and relocate to virtual address */
+ call relocate
+
+ /* Initialize task_struct pointer */
+ li tp, -THREAD_SIZE
+ add tp, tp, sp
+
+ tail smp_callin
+#endif
+
+.Lsecondary_park:
+ /* We lack SMP support or have too many harts, so park this hart */
+ wfi
+ j .Lsecondary_park
+END(_start)
+
+__PAGE_ALIGNED_BSS
+ /* Empty zero page */
+ .balign PAGE_SIZE
+ENTRY(empty_zero_page)
+ .fill (empty_zero_page + PAGE_SIZE) - ., 1, 0x00
+END(empty_zero_page)
diff --git a/arch/riscv/kernel/irq.c b/arch/riscv/kernel/irq.c
new file mode 100644
index 000000000000..737d7cce2c6d
--- /dev/null
+++ b/arch/riscv/kernel/irq.c
@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/irqchip.h>
+
+void __init init_IRQ(void)
+{
+ irqchip_init();
+}
diff --git a/arch/riscv/kernel/module.c b/arch/riscv/kernel/module.c
new file mode 100644
index 000000000000..753cb9894feb
--- /dev/null
+++ b/arch/riscv/kernel/module.c
@@ -0,0 +1,215 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * Copyright (C) 2017 Zihao Yu
+ */
+
+#include <linux/elf.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/moduleloader.h>
+
+static int apply_r_riscv_64_rela(struct module *me, u32 *location, Elf_Addr v)
+{
+ *(u64 *)location = v;
+ return 0;
+}
+
+static int apply_r_riscv_branch_rela(struct module *me, u32 *location,
+ Elf_Addr v)
+{
+ s64 offset = (void *)v - (void *)location;
+ u32 imm12 = (offset & 0x1000) << (31 - 12);
+ u32 imm11 = (offset & 0x800) >> (11 - 7);
+ u32 imm10_5 = (offset & 0x7e0) << (30 - 10);
+ u32 imm4_1 = (offset & 0x1e) << (11 - 4);
+
+ *location = (*location & 0x1fff07f) | imm12 | imm11 | imm10_5 | imm4_1;
+ return 0;
+}
+
+static int apply_r_riscv_jal_rela(struct module *me, u32 *location,
+ Elf_Addr v)
+{
+ s64 offset = (void *)v - (void *)location;
+ u32 imm20 = (offset & 0x100000) << (31 - 20);
+ u32 imm19_12 = (offset & 0xff000);
+ u32 imm11 = (offset & 0x800) << (20 - 11);
+ u32 imm10_1 = (offset & 0x7fe) << (30 - 10);
+
+ *location = (*location & 0xfff) | imm20 | imm19_12 | imm11 | imm10_1;
+ return 0;
+}
+
+static int apply_r_riscv_pcrel_hi20_rela(struct module *me, u32 *location,
+ Elf_Addr v)
+{
+ s64 offset = (void *)v - (void *)location;
+ s32 hi20;
+
+ if (offset != (s32)offset) {
+ pr_err(
+ "%s: target %016llx can not be addressed by the 32-bit offset from PC = %p\n",
+ me->name, v, location);
+ return -EINVAL;
+ }
+
+ hi20 = (offset + 0x800) & 0xfffff000;
+ *location = (*location & 0xfff) | hi20;
+ return 0;
+}
+
+static int apply_r_riscv_pcrel_lo12_i_rela(struct module *me, u32 *location,
+ Elf_Addr v)
+{
+ /* v is the lo12 value to fill. It is calculated before calling this
+ * handler.
+ */
+ *location = (*location & 0xfffff) | ((v & 0xfff) << 20);
+ return 0;
+}
+
+static int apply_r_riscv_pcrel_lo12_s_rela(struct module *me, u32 *location,
+ Elf_Addr v)
+{
+ /* v is the lo12 value to fill. It is calculated before calling this
+ * handler.
+ */
+ u32 imm11_5 = (v & 0xfe0) << (31 - 11);
+ u32 imm4_0 = (v & 0x1f) << (11 - 4);
+
+ *location = (*location & 0x1fff07f) | imm11_5 | imm4_0;
+ return 0;
+}
+
+static int apply_r_riscv_call_plt_rela(struct module *me, u32 *location,
+ Elf_Addr v)
+{
+ s64 offset = (void *)v - (void *)location;
+ s32 fill_v = offset;
+ u32 hi20, lo12;
+
+ if (offset != fill_v) {
+ pr_err(
+ "%s: target %016llx can not be addressed by the 32-bit offset from PC = %p\n",
+ me->name, v, location);
+ return -EINVAL;
+ }
+
+ hi20 = (offset + 0x800) & 0xfffff000;
+ lo12 = (offset - hi20) & 0xfff;
+ *location = (*location & 0xfff) | hi20;
+ *(location + 1) = (*(location + 1) & 0xfffff) | (lo12 << 20);
+ return 0;
+}
+
+static int apply_r_riscv_relax_rela(struct module *me, u32 *location,
+ Elf_Addr v)
+{
+ return 0;
+}
+
+static int (*reloc_handlers_rela[]) (struct module *me, u32 *location,
+ Elf_Addr v) = {
+ [R_RISCV_64] = apply_r_riscv_64_rela,
+ [R_RISCV_BRANCH] = apply_r_riscv_branch_rela,
+ [R_RISCV_JAL] = apply_r_riscv_jal_rela,
+ [R_RISCV_PCREL_HI20] = apply_r_riscv_pcrel_hi20_rela,
+ [R_RISCV_PCREL_LO12_I] = apply_r_riscv_pcrel_lo12_i_rela,
+ [R_RISCV_PCREL_LO12_S] = apply_r_riscv_pcrel_lo12_s_rela,
+ [R_RISCV_CALL_PLT] = apply_r_riscv_call_plt_rela,
+ [R_RISCV_RELAX] = apply_r_riscv_relax_rela,
+};
+
+int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
+ unsigned int symindex, unsigned int relsec,
+ struct module *me)
+{
+ Elf_Rela *rel = (void *) sechdrs[relsec].sh_addr;
+ int (*handler)(struct module *me, u32 *location, Elf_Addr v);
+ Elf_Sym *sym;
+ u32 *location;
+ unsigned int i, type;
+ Elf_Addr v;
+ int res;
+
+ pr_debug("Applying relocate section %u to %u\n", relsec,
+ sechdrs[relsec].sh_info);
+
+ for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
+ /* This is where to make the change */
+ location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
+ + rel[i].r_offset;
+ /* This is the symbol it is referring to */
+ sym = (Elf_Sym *)sechdrs[symindex].sh_addr
+ + ELF_RISCV_R_SYM(rel[i].r_info);
+ if (IS_ERR_VALUE(sym->st_value)) {
+ /* Ignore unresolved weak symbol */
+ if (ELF_ST_BIND(sym->st_info) == STB_WEAK)
+ continue;
+ printk(KERN_WARNING "%s: Unknown symbol %s\n",
+ me->name, strtab + sym->st_name);
+ return -ENOENT;
+ }
+
+ type = ELF_RISCV_R_TYPE(rel[i].r_info);
+
+ if (type < ARRAY_SIZE(reloc_handlers_rela))
+ handler = reloc_handlers_rela[type];
+ else
+ handler = NULL;
+
+ if (!handler) {
+ pr_err("%s: Unknown relocation type %u\n",
+ me->name, type);
+ return -EINVAL;
+ }
+
+ v = sym->st_value + rel[i].r_addend;
+
+ if (type == R_RISCV_PCREL_LO12_I || type == R_RISCV_PCREL_LO12_S) {
+ unsigned int j;
+
+ for (j = 0; j < sechdrs[relsec].sh_size / sizeof(*rel); j++) {
+ u64 hi20_loc =
+ sechdrs[sechdrs[relsec].sh_info].sh_addr
+ + rel[j].r_offset;
+ /* Find the corresponding HI20 PC-relative relocation entry */
+ if (hi20_loc == sym->st_value) {
+ Elf_Sym *hi20_sym =
+ (Elf_Sym *)sechdrs[symindex].sh_addr
+ + ELF_RISCV_R_SYM(rel[j].r_info);
+ u64 hi20_sym_val =
+ hi20_sym->st_value
+ + rel[j].r_addend;
+ /* Calculate lo12 */
+ s64 offset = hi20_sym_val - hi20_loc;
+ s32 hi20 = (offset + 0x800) & 0xfffff000;
+ s32 lo12 = offset - hi20;
+ v = lo12;
+ break;
+ }
+ }
+ if (j == sechdrs[relsec].sh_size / sizeof(*rel)) {
+ pr_err(
+ "%s: Can not find HI20 PC-relative relocation information\n",
+ me->name);
+ return -EINVAL;
+ }
+ }
+
+ res = handler(me, location, v);
+ if (res)
+ return res;
+ }
+
+ return 0;
+}
diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
new file mode 100644
index 000000000000..c10146ae317d
--- /dev/null
+++ b/arch/riscv/kernel/process.c
@@ -0,0 +1,132 @@
+/*
+ * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
+ * Chen Liqin <liqin.chen@xxxxxxxxxxxxx>
+ * Lennox Wu <lennox.wu@xxxxxxxxxxxxx>
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see the file COPYING, or write
+ * to the Free Software Foundation, Inc.,
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/sched/task_stack.h>
+#include <linux/tick.h>
+#include <linux/ptrace.h>
+
+#include <asm/unistd.h>
+#include <asm/uaccess.h>
+#include <asm/processor.h>
+#include <asm/csr.h>
+#include <asm/string.h>
+#include <asm/switch_to.h>
+
+extern asmlinkage void ret_from_fork(void);
+extern asmlinkage void ret_from_kernel_thread(void);
+
+void arch_cpu_idle(void)
+{
+ wait_for_interrupt();
+ local_irq_enable();
+}
+
+void show_regs(struct pt_regs *regs)
+{
+ show_regs_print_info(KERN_DEFAULT);
+
+ printk(KERN_CONT "sepc: " REG_FMT " ra : " REG_FMT " sp : " REG_FMT "\n",
+ regs->sepc, regs->ra, regs->sp);
+ printk(KERN_CONT " gp : " REG_FMT " tp : " REG_FMT " t0 : " REG_FMT "\n",
+ regs->gp, regs->tp, regs->t0);
+ printk(KERN_CONT " t1 : " REG_FMT " t2 : " REG_FMT " s0 : " REG_FMT "\n",
+ regs->t1, regs->t2, regs->s0);
+ printk(KERN_CONT " s1 : " REG_FMT " a0 : " REG_FMT " a1 : " REG_FMT "\n",
+ regs->s1, regs->a0, regs->a1);
+ printk(KERN_CONT " a2 : " REG_FMT " a3 : " REG_FMT " a4 : " REG_FMT "\n",
+ regs->a2, regs->a3, regs->a4);
+ printk(KERN_CONT " a5 : " REG_FMT " a6 : " REG_FMT " a7 : " REG_FMT "\n",
+ regs->a5, regs->a6, regs->a7);
+ printk(KERN_CONT " s2 : " REG_FMT " s3 : " REG_FMT " s4 : " REG_FMT "\n",
+ regs->s2, regs->s3, regs->s4);
+ printk(KERN_CONT " s5 : " REG_FMT " s6 : " REG_FMT " s7 : " REG_FMT "\n",
+ regs->s5, regs->s6, regs->s7);
+ printk(KERN_CONT " s8 : " REG_FMT " s9 : " REG_FMT " s10: " REG_FMT "\n",
+ regs->s8, regs->s9, regs->s10);
+ printk(KERN_CONT " s11: " REG_FMT " t3 : " REG_FMT " t4 : " REG_FMT "\n",
+ regs->s11, regs->t3, regs->t4);
+ printk(KERN_CONT " t5 : " REG_FMT " t6 : " REG_FMT "\n",
+ regs->t5, regs->t6);
+
+ printk(KERN_CONT "sstatus: " REG_FMT " sbadaddr: " REG_FMT " scause: " REG_FMT "\n",
+ regs->sstatus, regs->sbadaddr, regs->scause);
+}
+
+void start_thread(struct pt_regs *regs, unsigned long pc,
+ unsigned long sp)
+{
+ regs->sstatus = SR_PIE /* User mode, irqs on */ | SR_FS_INITIAL;
+#ifndef CONFIG_RV_PUM
+ regs->sstatus |= SR_SUM
+#endif
+ regs->sepc = pc;
+ regs->sp = sp;
+ set_fs(USER_DS);
+}
+
+void flush_thread(void)
+{
+ /* Reset FPU context
+ * frm: round to nearest, ties to even (IEEE default)
+ * fflags: accrued exceptions cleared
+ */
+ memset(¤t->thread.fstate, 0,
+ sizeof(struct user_fpregs_struct));
+}
+
+int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
+{
+ fstate_save(src, task_pt_regs(src));
+ *dst = *src;
+ return 0;
+}
+
+int copy_thread(unsigned long clone_flags, unsigned long usp,
+ unsigned long arg, struct task_struct *p)
+{
+ struct pt_regs *childregs = task_pt_regs(p);
+
+ /* p->thread holds context to be restored by __switch_to() */
+ if (unlikely(p->flags & PF_KTHREAD)) {
+ /* Kernel thread */
+ const register unsigned long gp __asm__ ("gp");
+ memset(childregs, 0, sizeof(struct pt_regs));
+ childregs->gp = gp;
+ childregs->sstatus = SR_PS | SR_PIE; /* Supervisor, irqs on */
+
+ p->thread.ra = (unsigned long)ret_from_kernel_thread;
+ p->thread.s[0] = usp; /* fn */
+ p->thread.s[1] = arg;
+ } else {
+ *childregs = *(current_pt_regs());
+ if (usp) /* User fork */
+ childregs->sp = usp;
+ if (clone_flags & CLONE_SETTLS)
+ childregs->tp = childregs->a5;
+ childregs->a0 = 0; /* Return value of fork() */
+ p->thread.ra = (unsigned long)ret_from_fork;
+ }
+ p->thread.sp = (unsigned long)childregs; /* kernel sp */
+ return 0;
+}
diff --git a/arch/riscv/kernel/ptrace.c b/arch/riscv/kernel/ptrace.c
new file mode 100644
index 000000000000..69b3b2d10664
--- /dev/null
+++ b/arch/riscv/kernel/ptrace.c
@@ -0,0 +1,147 @@
+/*
+ * Copyright 2010 Tilera Corporation. All Rights Reserved.
+ * Copyright 2015 Regents of the University of California
+ * Copyright 2017 SiFive
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * Copied from arch/tile/kernel/ptrace.c
+ */
+
+#include <asm/ptrace.h>
+#include <asm/syscall.h>
+#include <asm/thread_info.h>
+#include <linux/ptrace.h>
+#include <linux/elf.h>
+#include <linux/regset.h>
+#include <linux/sched.h>
+#include <linux/sched/task_stack.h>
+#include <linux/tracehook.h>
+#include <trace/events/syscalls.h>
+
+enum riscv_regset {
+ REGSET_X,
+};
+
+/*
+ * Get registers from task and ready the result for userspace.
+ */
+static char *getregs(struct task_struct *child, struct pt_regs *uregs)
+{
+ *uregs = *task_pt_regs(child);
+ return (char *)uregs;
+}
+
+/* Put registers back to task. */
+static void putregs(struct task_struct *child, struct pt_regs *uregs)
+{
+ struct pt_regs *regs = task_pt_regs(child);
+ *regs = *uregs;
+}
+
+static int riscv_gpr_get(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ void *kbuf, void __user *ubuf)
+{
+ struct pt_regs regs;
+
+ getregs(target, ®s);
+
+ return user_regset_copyout(&pos, &count, &kbuf, &ubuf, ®s, 0,
+ sizeof(regs));
+}
+
+static int riscv_gpr_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ int ret;
+ struct pt_regs regs;
+
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, ®s, 0,
+ sizeof(regs));
+ if (ret)
+ return ret;
+
+ putregs(target, ®s);
+
+ return 0;
+}
+
+
+static const struct user_regset riscv_user_regset[] = {
+ [REGSET_X] = {
+ .core_note_type = NT_PRSTATUS,
+ .n = ELF_NGREG,
+ .size = sizeof(elf_greg_t),
+ .align = sizeof(elf_greg_t),
+ .get = &riscv_gpr_get,
+ .set = &riscv_gpr_set,
+ },
+};
+
+static const struct user_regset_view riscv_user_native_view = {
+ .name = "riscv",
+ .e_machine = EM_RISCV,
+ .regsets = riscv_user_regset,
+ .n = ARRAY_SIZE(riscv_user_regset),
+};
+
+const struct user_regset_view *task_user_regset_view(struct task_struct *task)
+{
+ return &riscv_user_native_view;
+}
+
+void ptrace_disable(struct task_struct *child)
+{
+ clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+}
+
+long arch_ptrace(struct task_struct *child, long request,
+ unsigned long addr, unsigned long data)
+{
+ long ret = -EIO;
+
+ switch (request) {
+ default:
+ ret = ptrace_request(child, request, addr, data);
+ break;
+ }
+
+ return ret;
+}
+
+/* Allows PTRACE_SYSCALL to work. These are called from entry.S in
+ * {handle,ret_from}_syscall.
+ */
+void do_syscall_trace_enter(struct pt_regs *regs)
+{
+ if (test_thread_flag(TIF_SYSCALL_TRACE))
+ if (tracehook_report_syscall_entry(regs))
+ syscall_set_nr(current, regs, -1);
+
+#ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
+ if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+ trace_sys_enter(regs, syscall_get_nr(current, regs));
+#endif
+}
+
+void do_syscall_trace_exit(struct pt_regs *regs)
+{
+ if (test_thread_flag(TIF_SYSCALL_TRACE))
+ tracehook_report_syscall_exit(regs, 0);
+
+#ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
+ if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+ trace_sys_exit(regs, regs->regs[0]);
+#endif
+}
diff --git a/arch/riscv/kernel/reset.c b/arch/riscv/kernel/reset.c
new file mode 100644
index 000000000000..2a53d26ffdd6
--- /dev/null
+++ b/arch/riscv/kernel/reset.c
@@ -0,0 +1,36 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/reboot.h>
+#include <linux/export.h>
+#include <asm/sbi.h>
+
+void (*pm_power_off)(void) = machine_power_off;
+EXPORT_SYMBOL(pm_power_off);
+
+void machine_restart(char *cmd)
+{
+ do_kernel_restart(cmd);
+ while (1);
+}
+
+void machine_halt(void)
+{
+ machine_power_off();
+}
+
+void machine_power_off(void)
+{
+ sbi_shutdown();
+ while (1);
+}
diff --git a/arch/riscv/kernel/riscv_ksyms.c b/arch/riscv/kernel/riscv_ksyms.c
new file mode 100644
index 000000000000..ab0db6d48101
--- /dev/null
+++ b/arch/riscv/kernel/riscv_ksyms.c
@@ -0,0 +1,16 @@
+/*
+ * Copyright (C) 2017 Zihao Yu
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/export.h>
+#include <linux/uaccess.h>
+
+/*
+ * Assembly functions that may be used (directly or indirectly) by modules
+ */
+EXPORT_SYMBOL(__copy_user);
+
diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
new file mode 100644
index 000000000000..9ed70e84d74e
--- /dev/null
+++ b/arch/riscv/kernel/setup.c
@@ -0,0 +1,240 @@
+/*
+ * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
+ * Chen Liqin <liqin.chen@xxxxxxxxxxxxx>
+ * Lennox Wu <lennox.wu@xxxxxxxxxxxxx>
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see the file COPYING, or write
+ * to the Free Software Foundation, Inc.,
+ */
+
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/memblock.h>
+#include <linux/sched.h>
+#include <linux/initrd.h>
+#include <linux/console.h>
+#include <linux/screen_info.h>
+#include <linux/of_fdt.h>
+#include <linux/of_platform.h>
+#include <linux/sched/task.h>
+
+#include <asm/setup.h>
+#include <asm/sections.h>
+#include <asm/pgtable.h>
+#include <asm/smp.h>
+#include <asm/sbi.h>
+#include <asm/tlbflush.h>
+#include <asm/thread_info.h>
+
+#ifdef CONFIG_DUMMY_CONSOLE
+struct screen_info screen_info = {
+ .orig_video_lines = 30,
+ .orig_video_cols = 80,
+ .orig_video_mode = 0,
+ .orig_video_ega_bx = 0,
+ .orig_video_isVGA = 1,
+ .orig_video_points = 8
+};
+#endif
+
+#ifdef CONFIG_CMDLINE_BOOL
+static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
+#endif /* CONFIG_CMDLINE_BOOL */
+
+unsigned long va_pa_offset;
+unsigned long pfn_base;
+
+/* The lucky hart to first increment this variable will boot the other cores */
+atomic_t hart_lottery;
+
+#ifdef CONFIG_BLK_DEV_INITRD
+static void __init setup_initrd(void)
+{
+ extern char __initramfs_start[];
+ extern unsigned long __initramfs_size;
+ unsigned long size;
+
+ if (__initramfs_size > 0) {
+ initrd_start = (unsigned long)(&__initramfs_start);
+ initrd_end = initrd_start + __initramfs_size;
+ }
+
+ if (initrd_start >= initrd_end) {
+ printk(KERN_INFO "initrd not found or empty");
+ goto disable;
+ }
+ if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
+ printk(KERN_ERR "initrd extends beyond end of memory");
+ goto disable;
+ }
+
+ size = initrd_end - initrd_start;
+ memblock_reserve(__pa(initrd_start), size);
+ initrd_below_start_ok = 1;
+
+ printk(KERN_INFO "Initial ramdisk at: 0x%p (%lu bytes)\n",
+ (void *)(initrd_start), size);
+ return;
+disable:
+ printk(KERN_CONT " - disabling initrd\n");
+ initrd_start = 0;
+ initrd_end = 0;
+}
+#endif /* CONFIG_BLK_DEV_INITRD */
+
+pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
+pgd_t trampoline_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
+
+#ifndef __PAGETABLE_PMD_FOLDED
+#define NUM_SWAPPER_PMDS ((uintptr_t)-PAGE_OFFSET >> PGDIR_SHIFT)
+pmd_t swapper_pmd[PTRS_PER_PMD*((-PAGE_OFFSET)/PGDIR_SIZE)] __page_aligned_bss;
+pmd_t trampoline_pmd[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
+#endif
+
+asmlinkage void __init setup_vm(void)
+{
+ extern char _start;
+ uintptr_t i;
+ uintptr_t pa = (uintptr_t) &_start;
+ pgprot_t prot = __pgprot(pgprot_val(PAGE_KERNEL) | _PAGE_EXEC);
+
+ va_pa_offset = PAGE_OFFSET - pa;
+ pfn_base = PFN_DOWN(pa);
+
+ /* Sanity check alignment and size */
+ BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0);
+ BUG_ON((pa % (PAGE_SIZE * PTRS_PER_PTE)) != 0);
+
+#ifndef __PAGETABLE_PMD_FOLDED
+ trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] =
+ pfn_pgd(PFN_DOWN((uintptr_t)trampoline_pmd),
+ __pgprot(_PAGE_TABLE));
+ trampoline_pmd[0] = pfn_pmd(PFN_DOWN(pa), prot);
+
+ for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) {
+ size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i;
+ swapper_pg_dir[o] =
+ pfn_pgd(PFN_DOWN((uintptr_t)swapper_pmd) + i,
+ __pgprot(_PAGE_TABLE));
+ }
+ for (i = 0; i < ARRAY_SIZE(swapper_pmd); i++)
+ swapper_pmd[i] = pfn_pmd(PFN_DOWN(pa + i * PMD_SIZE), prot);
+#else
+ trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] =
+ pfn_pgd(PFN_DOWN(pa), prot);
+
+ for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) {
+ size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i;
+ swapper_pg_dir[o] =
+ pfn_pgd(PFN_DOWN(pa + i * PGDIR_SIZE), prot);
+ }
+#endif
+}
+
+void __init sbi_save(unsigned int hartid, void *dtb)
+{
+ early_init_dt_scan(__va(dtb));
+}
+
+/* Allow the user to manually add a memory region (in case DTS is broken); "mem_end=nn[KkMmGg]" */
+static int __init mem_end_override(char *p)
+{
+ resource_size_t base, end;
+
+ if (!p)
+ return -EINVAL;
+ base = (uintptr_t) __pa(PAGE_OFFSET);
+ end = memparse(p, &p) & PMD_MASK;
+ if (end == 0)
+ return -EINVAL;
+ memblock_add(base, end - base);
+ return 0;
+}
+early_param("mem_end", mem_end_override);
+
+static void __init setup_bootmem(void)
+{
+ struct memblock_region *reg;
+ phys_addr_t mem_size = 0;
+
+ /* Find the memory region containing the kernel */
+ for_each_memblock(memory, reg) {
+ phys_addr_t vmlinux_end = __pa(_end);
+ phys_addr_t end = reg->base + reg->size;
+
+ if (reg->base <= vmlinux_end && vmlinux_end <= end) {
+ /* Reserve from the start of the region to the end of
+ * the kernel
+ */
+ memblock_reserve(reg->base, vmlinux_end - reg->base);
+ mem_size = min(reg->size, (phys_addr_t)-PAGE_OFFSET);
+ }
+ }
+ BUG_ON(mem_size == 0);
+
+ set_max_mapnr(PFN_DOWN(mem_size));
+ max_low_pfn = pfn_base + PFN_DOWN(mem_size);
+
+#ifdef CONFIG_BLK_DEV_INITRD
+ setup_initrd();
+#endif /* CONFIG_BLK_DEV_INITRD */
+
+ early_init_fdt_reserve_self();
+ early_init_fdt_scan_reserved_mem();
+ memblock_allow_resize();
+ memblock_dump_all();
+}
+
+void __init setup_arch(char **cmdline_p)
+{
+#ifdef CONFIG_CMDLINE_BOOL
+#ifdef CONFIG_CMDLINE_OVERRIDE
+ strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
+#else
+ if (builtin_cmdline[0] != '\0') {
+ /* Append bootloader command line to built-in */
+ strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE);
+ strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE);
+ strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
+ }
+#endif /* CONFIG_CMDLINE_OVERRIDE */
+#endif /* CONFIG_CMDLINE_BOOL */
+ *cmdline_p = boot_command_line;
+
+ parse_early_param();
+
+ init_mm.start_code = (unsigned long) _stext;
+ init_mm.end_code = (unsigned long) _etext;
+ init_mm.end_data = (unsigned long) _edata;
+ init_mm.brk = (unsigned long) _end;
+
+ setup_bootmem();
+ paging_init();
+ unflatten_device_tree();
+
+#ifdef CONFIG_SMP
+ setup_smp();
+#endif
+
+#ifdef CONFIG_DUMMY_CONSOLE
+ conswitchp = &dummy_con;
+#endif
+}
+
+static int __init riscv_device_init(void)
+{
+ return of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
+}
+subsys_initcall_sync(riscv_device_init);
diff --git a/arch/riscv/kernel/signal.c b/arch/riscv/kernel/signal.c
new file mode 100644
index 000000000000..ea14c47f28ac
--- /dev/null
+++ b/arch/riscv/kernel/signal.c
@@ -0,0 +1,257 @@
+/*
+ * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
+ * Chen Liqin <liqin.chen@xxxxxxxxxxxxx>
+ * Lennox Wu <lennox.wu@xxxxxxxxxxxxx>
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see the file COPYING, or write
+ * to the Free Software Foundation, Inc.,
+ */
+
+#include <linux/signal.h>
+#include <linux/uaccess.h>
+#include <linux/syscalls.h>
+#include <linux/tracehook.h>
+#include <linux/linkage.h>
+
+#include <asm/ucontext.h>
+#include <asm/vdso.h>
+#include <asm/switch_to.h>
+#include <asm/csr.h>
+
+#define DEBUG_SIG 0
+
+struct rt_sigframe {
+ struct siginfo info;
+ struct ucontext uc;
+};
+
+static long restore_sigcontext(struct pt_regs *regs,
+ struct sigcontext __user *sc)
+{
+ struct task_struct *task = current;
+ long err;
+ /* sc_regs is structured the same as the start of pt_regs */
+ err = __copy_from_user(regs, &sc->sc_regs, sizeof(sc->sc_regs));
+ err |= __copy_from_user(&task->thread.fstate, &sc->sc_fpregs,
+ sizeof(sc->sc_fpregs));
+ if (likely(!err))
+ fstate_restore(task, regs);
+ return err;
+}
+
+SYSCALL_DEFINE0(rt_sigreturn)
+{
+ struct pt_regs *regs = current_pt_regs();
+ struct rt_sigframe __user *frame;
+ struct task_struct *task;
+ sigset_t set;
+
+ /* Always make any pending restarted system calls return -EINTR */
+ current->restart_block.fn = do_no_restart_syscall;
+
+ frame = (struct rt_sigframe __user *)regs->sp;
+
+ if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
+ goto badframe;
+
+ if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
+ goto badframe;
+
+ set_current_blocked(&set);
+
+ if (restore_sigcontext(regs, &frame->uc.uc_mcontext))
+ goto badframe;
+
+ if (restore_altstack(&frame->uc.uc_stack))
+ goto badframe;
+
+ return regs->a0;
+
+badframe:
+ task = current;
+ if (show_unhandled_signals) {
+ pr_info_ratelimited(
+ "%s[%d]: bad frame in %s: frame=%p pc=%p sp=%p\n",
+ task->comm, task_pid_nr(task), __func__,
+ frame, (void *)regs->sepc, (void *)regs->sp);
+ }
+ force_sig(SIGSEGV, task);
+ return 0;
+}
+
+static long setup_sigcontext(struct sigcontext __user *sc,
+ struct pt_regs *regs)
+{
+ struct task_struct *task = current;
+ long err;
+ /* sc_regs is structured the same as the start of pt_regs */
+ err = __copy_to_user(&sc->sc_regs, regs, sizeof(sc->sc_regs));
+ fstate_save(task, regs);
+ err |= __copy_to_user(&sc->sc_fpregs, &task->thread.fstate,
+ sizeof(sc->sc_fpregs));
+ return err;
+}
+
+static inline void __user *get_sigframe(struct ksignal *ksig,
+ struct pt_regs *regs, size_t framesize)
+{
+ unsigned long sp;
+ /* Default to using normal stack */
+ sp = regs->sp;
+
+ /*
+ * If we are on the alternate signal stack and would overflow it, don't.
+ * Return an always-bogus address instead so we will die with SIGSEGV.
+ */
+ if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize)))
+ return (void __user __force *)(-1UL);
+
+ /* This is the X/Open sanctioned signal stack switching. */
+ sp = sigsp(sp, ksig) - framesize;
+
+ /* Align the stack frame. */
+ sp &= ~0xfUL;
+
+ return (void __user *)sp;
+}
+
+
+static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
+ struct pt_regs *regs)
+{
+ struct rt_sigframe __user *frame;
+ long err = 0;
+
+ frame = get_sigframe(ksig, regs, sizeof(*frame));
+ if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+ return -EFAULT;
+
+ err |= copy_siginfo_to_user(&frame->info, &ksig->info);
+
+ /* Create the ucontext. */
+ err |= __put_user(0, &frame->uc.uc_flags);
+ err |= __put_user(NULL, &frame->uc.uc_link);
+ err |= __save_altstack(&frame->uc.uc_stack, regs->sp);
+ err |= setup_sigcontext(&frame->uc.uc_mcontext, regs);
+ err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+ if (err)
+ return -EFAULT;
+
+ /* Set up to return from userspace. */
+ regs->ra = (unsigned long)VDSO_SYMBOL(
+ current->mm->context.vdso, rt_sigreturn);
+
+ /*
+ * Set up registers for signal handler.
+ * Registers that we don't modify keep the value they had from
+ * user-space at the time we took the signal.
+ * We always pass siginfo and mcontext, regardless of SA_SIGINFO,
+ * since some things rely on this (e.g. glibc's debug/segfault.c).
+ */
+ regs->sepc = (unsigned long)ksig->ka.sa.sa_handler;
+ regs->sp = (unsigned long)frame;
+ regs->a0 = ksig->sig; /* a0: signal number */
+ regs->a1 = (unsigned long)(&frame->info); /* a1: siginfo pointer */
+ regs->a2 = (unsigned long)(&frame->uc); /* a2: ucontext pointer */
+
+#if DEBUG_SIG
+ pr_info("SIG deliver (%s:%d): sig=%d pc=%p ra=%p sp=%p\n",
+ current->comm, task_pid_nr(current), ksig->sig,
+ (void *)regs->sepc, (void *)regs->ra, frame);
+#endif
+
+ return 0;
+}
+
+static void handle_signal(struct ksignal *ksig, struct pt_regs *regs)
+{
+ sigset_t *oldset = sigmask_to_save();
+ int ret;
+
+ /* Are we from a system call? */
+ if (regs->scause == EXC_SYSCALL) {
+ /* If so, check system call restarting.. */
+ switch (regs->a0) {
+ case -ERESTART_RESTARTBLOCK:
+ case -ERESTARTNOHAND:
+ regs->a0 = -EINTR;
+ break;
+
+ case -ERESTARTSYS:
+ if (!(ksig->ka.sa.sa_flags & SA_RESTART)) {
+ regs->a0 = -EINTR;
+ break;
+ }
+ /* fallthrough */
+ case -ERESTARTNOINTR:
+ regs->sepc -= 0x4;
+ break;
+ }
+ }
+
+ /* Set up the stack frame */
+ ret = setup_rt_frame(ksig, oldset, regs);
+
+ signal_setup_done(ret, ksig, 0);
+}
+
+static void do_signal(struct pt_regs *regs)
+{
+ struct ksignal ksig;
+
+ if (get_signal(&ksig)) {
+ /* Actually deliver the signal */
+ handle_signal(&ksig, regs);
+ return;
+ }
+
+ /* Did we come from a system call? */
+ if (regs->scause == EXC_SYSCALL) {
+ /* Restart the system call - no handlers present */
+ switch (regs->a0) {
+ case -ERESTARTNOHAND:
+ case -ERESTARTSYS:
+ case -ERESTARTNOINTR:
+ regs->sepc -= 0x4;
+ break;
+ case -ERESTART_RESTARTBLOCK:
+ regs->a7 = __NR_restart_syscall;
+ regs->sepc -= 0x4;
+ break;
+ }
+ }
+
+ /* If there is no signal to deliver, we just put the saved
+ * sigmask back.
+ */
+ restore_saved_sigmask();
+}
+
+/*
+ * notification of userspace execution resumption
+ * - triggered by the _TIF_WORK_MASK flags
+ */
+asmlinkage void do_notify_resume(struct pt_regs *regs,
+ unsigned long thread_info_flags)
+{
+ /* Handle pending signal delivery */
+ if (thread_info_flags & _TIF_SIGPENDING)
+ do_signal(regs);
+
+ if (thread_info_flags & _TIF_NOTIFY_RESUME) {
+ clear_thread_flag(TIF_NOTIFY_RESUME);
+ tracehook_notify_resume(regs);
+ }
+}
diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
new file mode 100644
index 000000000000..b65c0e1020e3
--- /dev/null
+++ b/arch/riscv/kernel/smp.c
@@ -0,0 +1,110 @@
+/*
+ * SMP initialisation and IPI support
+ * Based on arch/arm64/kernel/smp.c
+ *
+ * Copyright (C) 2012 ARM Ltd.
+ * Copyright (C) 2015 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/smp.h>
+#include <linux/sched.h>
+
+#include <asm/sbi.h>
+#include <asm/tlbflush.h>
+#include <asm/cacheflush.h>
+
+/* A collection of single bit ipi messages. */
+static struct {
+ unsigned long bits ____cacheline_aligned;
+} ipi_data[NR_CPUS] __cacheline_aligned;
+
+enum ipi_message_type {
+ IPI_RESCHEDULE,
+ IPI_CALL_FUNC,
+ IPI_MAX
+};
+
+irqreturn_t handle_ipi(void)
+{
+ unsigned long *pending_ipis = &ipi_data[smp_processor_id()].bits;
+
+ /* Clear pending IPI */
+ csr_clear(sip, SIE_SSIE);
+
+ while (true) {
+ unsigned long ops;
+
+ /* Order bit clearing and data access. */
+ mb(); // test
+
+ ops = xchg(pending_ipis, 0);
+ if (ops == 0)
+ return IRQ_HANDLED;
+
+ if (ops & (1 << IPI_RESCHEDULE))
+ scheduler_ipi();
+
+ if (ops & (1 << IPI_CALL_FUNC))
+ generic_smp_call_function_interrupt();
+
+ BUG_ON((ops >> IPI_MAX) != 0);
+
+ /* Order data access and bit testing. */
+ mb();
+ }
+
+ return IRQ_HANDLED;
+}
+
+static void
+send_ipi_message(const struct cpumask *to_whom, enum ipi_message_type operation)
+{
+ int i;
+
+ mb();
+ for_each_cpu(i, to_whom)
+ set_bit(operation, &ipi_data[i].bits);
+
+ mb();
+ sbi_send_ipi(cpumask_bits(to_whom));
+}
+
+void arch_send_call_function_ipi_mask(struct cpumask *mask)
+{
+ send_ipi_message(mask, IPI_CALL_FUNC);
+}
+
+void arch_send_call_function_single_ipi(int cpu)
+{
+ send_ipi_message(cpumask_of(cpu), IPI_CALL_FUNC);
+}
+
+static void ipi_stop(void *unused)
+{
+ while (1)
+ wait_for_interrupt();
+}
+
+void smp_send_stop(void)
+{
+ on_each_cpu(ipi_stop, NULL, 1);
+}
+
+void smp_send_reschedule(int cpu)
+{
+ send_ipi_message(cpumask_of(cpu), IPI_RESCHEDULE);
+}
diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c
new file mode 100644
index 000000000000..7043bbbfbc1e
--- /dev/null
+++ b/arch/riscv/kernel/smpboot.c
@@ -0,0 +1,103 @@
+/*
+ * SMP initialisation and IPI support
+ * Based on arch/arm64/kernel/smp.c
+ *
+ * Copyright (C) 2012 ARM Ltd.
+ * Copyright (C) 2015 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <linux/kernel_stat.h>
+#include <linux/notifier.h>
+#include <linux/cpu.h>
+#include <linux/percpu.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/irq.h>
+#include <linux/of.h>
+#include <linux/sched/task_stack.h>
+#include <asm/mmu_context.h>
+#include <asm/tlbflush.h>
+#include <asm/sections.h>
+#include <asm/sbi.h>
+
+void *__cpu_up_stack_pointer[NR_CPUS];
+
+void __init smp_prepare_boot_cpu(void)
+{
+}
+
+void __init smp_prepare_cpus(unsigned int max_cpus)
+{
+}
+
+void __init setup_smp(void)
+{
+ struct device_node *dn = NULL;
+ int hart, im_okay_therefore_i_am = 0;
+
+ while ((dn = of_find_node_by_type(dn, "cpu"))) {
+ hart = riscv_of_processor_hart(dn);
+ if (hart >= 0) {
+ set_cpu_possible(hart, true);
+ set_cpu_present(hart, true);
+ if (hart == smp_processor_id()) {
+ BUG_ON(im_okay_therefore_i_am);
+ im_okay_therefore_i_am = 1;
+ }
+ }
+ }
+
+ BUG_ON(!im_okay_therefore_i_am);
+}
+
+int __cpu_up(unsigned int cpu, struct task_struct *tidle)
+{
+ /* Signal cpu to start */
+ mb();
+ __cpu_up_stack_pointer[cpu] = task_stack_page(tidle) + THREAD_SIZE;
+
+ while (!cpu_online(cpu))
+ cpu_relax();
+
+ return 0;
+}
+
+void __init smp_cpus_done(unsigned int max_cpus)
+{
+}
+
+/*
+ * C entry point for a secondary processor.
+ */
+asmlinkage void __init smp_callin(void)
+{
+ struct mm_struct *mm = &init_mm;
+
+ /* All kernel threads share the same mm context. */
+ atomic_inc(&mm->mm_count);
+ current->active_mm = mm;
+
+ trap_init();
+ init_clockevent();
+ notify_cpu_starting(smp_processor_id());
+ set_cpu_online(smp_processor_id(), 1);
+ local_flush_tlb_all();
+ local_irq_enable();
+ preempt_disable();
+ cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
+}
diff --git a/arch/riscv/kernel/stacktrace.c b/arch/riscv/kernel/stacktrace.c
new file mode 100644
index 000000000000..109f5120d5c7
--- /dev/null
+++ b/arch/riscv/kernel/stacktrace.c
@@ -0,0 +1,177 @@
+/*
+ * Copyright (C) 2008 ARM Limited
+ * Copyright (C) 2014 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/export.h>
+#include <linux/kallsyms.h>
+#include <linux/sched.h>
+#include <linux/sched/debug.h>
+#include <linux/sched/task_stack.h>
+#include <linux/stacktrace.h>
+
+#ifdef CONFIG_FRAME_POINTER
+
+struct stackframe {
+ unsigned long fp;
+ unsigned long ra;
+};
+
+static void notrace walk_stackframe(struct task_struct *task,
+ struct pt_regs *regs, bool (*fn)(unsigned long, void *), void *arg)
+{
+ unsigned long fp, sp, pc;
+
+ if (regs) {
+ fp = GET_FP(regs);
+ sp = GET_USP(regs);
+ pc = GET_IP(regs);
+ } else if (task == NULL || task == current) {
+ const register unsigned long current_sp __asm__ ("sp");
+ fp = (unsigned long)__builtin_frame_address(0);
+ sp = current_sp;
+ pc = (unsigned long)walk_stackframe;
+ } else {
+ /* task blocked in __switch_to */
+ fp = task->thread.s[0];
+ sp = task->thread.sp;
+ pc = task->thread.ra;
+ }
+
+ for (;;) {
+ unsigned long low, high;
+ struct stackframe *frame;
+
+ if (unlikely(!__kernel_text_address(pc) || fn(pc, arg)))
+ break;
+
+ /* Validate frame pointer */
+ low = sp + sizeof(struct stackframe);
+ high = ALIGN(sp, THREAD_SIZE);
+ if (unlikely(fp < low || fp > high || fp & 0x7))
+ break;
+ /* Unwind stack frame */
+ frame = (struct stackframe *)fp - 1;
+ sp = fp;
+ fp = frame->fp;
+ pc = frame->ra - 0x4;
+ }
+}
+
+#else /* !CONFIG_FRAME_POINTER */
+
+static void notrace walk_stackframe(struct task_struct *task,
+ struct pt_regs *regs, bool (*fn)(unsigned long, void *), void *arg)
+{
+ unsigned long sp, pc;
+ unsigned long *ksp;
+
+ if (regs) {
+ sp = GET_USP(regs);
+ pc = GET_IP(regs);
+ } else if (task == NULL || task == current) {
+ const register unsigned long current_sp __asm__ ("sp");
+ sp = current_sp;
+ pc = (unsigned long)walk_stackframe;
+ } else {
+ /* task blocked in __switch_to */
+ sp = task->thread.sp;
+ pc = task->thread.ra;
+ }
+
+ if (unlikely(sp & 0x7))
+ return;
+
+ ksp = (unsigned long *)sp;
+ while (!kstack_end(ksp)) {
+ if (__kernel_text_address(pc) && unlikely(fn(pc, arg)))
+ break;
+ pc = (*ksp++) - 0x4;
+ }
+}
+
+#endif /* CONFIG_FRAME_POINTER */
+
+
+static bool print_trace_address(unsigned long pc, void *arg)
+{
+ print_ip_sym(pc);
+ return false;
+}
+
+void show_stack(struct task_struct *task, unsigned long *sp)
+{
+ printk("Call Trace:\n");
+ walk_stackframe(task, NULL, print_trace_address, NULL);
+}
+
+
+static bool save_wchan(unsigned long pc, void *arg)
+{
+ if (!in_sched_functions(pc)) {
+ unsigned long *p = arg;
+ *p = pc;
+ return true;
+ }
+ return false;
+}
+
+unsigned long get_wchan(struct task_struct *task)
+{
+ unsigned long pc = 0;
+
+ if (likely(task && task != current && task->state != TASK_RUNNING))
+ walk_stackframe(task, NULL, save_wchan, &pc);
+ return pc;
+}
+
+
+#ifdef CONFIG_STACKTRACE
+
+static bool __save_trace(unsigned long pc, void *arg, bool nosched)
+{
+ struct stack_trace *trace = arg;
+
+ if (unlikely(nosched && in_sched_functions(pc)))
+ return false;
+ if (unlikely(trace->skip > 0)) {
+ trace->skip--;
+ return false;
+ }
+
+ trace->entries[trace->nr_entries++] = pc;
+ return (trace->nr_entries >= trace->max_entries);
+}
+
+static bool save_trace(unsigned long pc, void *arg)
+{
+ return __save_trace(pc, arg, false);
+}
+
+/*
+ * Save stack-backtrace addresses into a stack_trace buffer.
+ */
+void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
+{
+ walk_stackframe(tsk, NULL, save_trace, trace);
+ if (trace->nr_entries < trace->max_entries)
+ trace->entries[trace->nr_entries++] = ULONG_MAX;
+}
+EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
+
+void save_stack_trace(struct stack_trace *trace)
+{
+ save_stack_trace_tsk(NULL, trace);
+}
+EXPORT_SYMBOL_GPL(save_stack_trace);
+
+#endif /* CONFIG_STACKTRACE */
diff --git a/arch/riscv/kernel/sys_riscv.c b/arch/riscv/kernel/sys_riscv.c
new file mode 100644
index 000000000000..33d40a5da4a1
--- /dev/null
+++ b/arch/riscv/kernel/sys_riscv.c
@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2014 Darius Rad <darius@xxxxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/syscalls.h>
+#include <asm/unistd.h>
+
+#ifdef CONFIG_64BIT
+SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
+ unsigned long, prot, unsigned long, flags,
+ unsigned long, fd, off_t, offset)
+{
+ if (unlikely(offset & (~PAGE_MASK)))
+ return -EINVAL;
+ return sys_mmap_pgoff(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
+}
+#else
+SYSCALL_DEFINE6(mmap2, unsigned long, addr, unsigned long, len,
+ unsigned long, prot, unsigned long, flags,
+ unsigned long, fd, off_t, offset)
+{
+ /* Note that the shift for mmap2 is constant (12),
+ * regardless of PAGE_SIZE
+ */
+ if (unlikely(offset & (~PAGE_MASK >> 12)))
+ return -EINVAL;
+ return sys_mmap_pgoff(addr, len, prot, flags, fd,
+ offset >> (PAGE_SHIFT - 12));
+}
+#endif /* !CONFIG_64BIT */
+
+#ifdef CONFIG_SYSRISCV_ATOMIC
+SYSCALL_DEFINE4(sysriscv, unsigned long, cmd, unsigned long, arg1,
+ unsigned long, arg2, unsigned long, arg3)
+{
+ unsigned long flags;
+ unsigned long prev;
+ unsigned int *ptr;
+ unsigned int err;
+
+ switch (cmd) {
+ case RISCV_ATOMIC_CMPXCHG:
+ ptr = (unsigned int *)arg1;
+ if (!access_ok(VERIFY_WRITE, ptr, sizeof(unsigned int)))
+ return -EFAULT;
+
+ preempt_disable();
+ raw_local_irq_save(flags);
+ err = __get_user(prev, ptr);
+ if (likely(!err && prev == arg2))
+ err = __put_user(arg3, ptr);
+ raw_local_irq_restore(flags);
+ preempt_enable();
+
+ return unlikely(err) ? err : prev;
+
+ case RISCV_ATOMIC_CMPXCHG64:
+ ptr = (unsigned int *)arg1;
+ if (!access_ok(VERIFY_WRITE, ptr, sizeof(unsigned long)))
+ return -EFAULT;
+
+ preempt_disable();
+ raw_local_irq_save(flags);
+ err = __get_user(prev, ptr);
+ if (likely(!err && prev == arg2))
+ err = __put_user(arg3, ptr);
+ raw_local_irq_restore(flags);
+ preempt_enable();
+
+ return unlikely(err) ? err : prev;
+ }
+
+ return -EINVAL;
+}
+#endif /* CONFIG_SYSRISCV_ATOMIC */
diff --git a/arch/riscv/kernel/syscall_table.c b/arch/riscv/kernel/syscall_table.c
new file mode 100644
index 000000000000..8fa239b67cbc
--- /dev/null
+++ b/arch/riscv/kernel/syscall_table.c
@@ -0,0 +1,25 @@
+/*
+ * Copyright (C) 2009 Arnd Bergmann <arnd@xxxxxxxx>
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/syscalls.h>
+
+#include <asm/syscalls.h>
+
+#undef __SYSCALL
+#define __SYSCALL(nr, call) [nr] = (call),
+
+void *sys_call_table[__NR_syscalls] = {
+ [0 ... __NR_syscalls - 1] = sys_ni_syscall,
+#include <asm/unistd.h>
+};
diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c
new file mode 100644
index 000000000000..3a4698199ecf
--- /dev/null
+++ b/arch/riscv/kernel/traps.c
@@ -0,0 +1,183 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/sched/debug.h>
+#include <linux/sched/signal.h>
+#include <linux/signal.h>
+#include <linux/kdebug.h>
+#include <linux/uaccess.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/irq.h>
+
+#include <asm/processor.h>
+#include <asm/ptrace.h>
+#include <asm/csr.h>
+
+int show_unhandled_signals = 1;
+
+extern asmlinkage void handle_exception(void);
+
+static DEFINE_SPINLOCK(die_lock);
+
+void die(struct pt_regs *regs, const char *str)
+{
+ static int die_counter;
+ int ret;
+
+ oops_enter();
+
+ spin_lock_irq(&die_lock);
+ console_verbose();
+ bust_spinlocks(1);
+
+ pr_emerg("%s [#%d]\n", str, ++die_counter);
+ print_modules();
+ show_regs(regs);
+
+ ret = notify_die(DIE_OOPS, str, regs, 0, regs->scause, SIGSEGV);
+
+ bust_spinlocks(0);
+ add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
+ spin_unlock_irq(&die_lock);
+ oops_exit();
+
+ if (in_interrupt())
+ panic("Fatal exception in interrupt");
+ if (panic_on_oops)
+ panic("Fatal exception");
+ if (ret != NOTIFY_STOP)
+ do_exit(SIGSEGV);
+}
+
+static inline void do_trap_siginfo(int signo, int code,
+ unsigned long addr, struct task_struct *tsk)
+{
+ siginfo_t info;
+
+ info.si_signo = signo;
+ info.si_errno = 0;
+ info.si_code = code;
+ info.si_addr = (void __user *)addr;
+ force_sig_info(signo, &info, tsk);
+}
+
+void do_trap(struct pt_regs *regs, int signo, int code,
+ unsigned long addr, struct task_struct *tsk)
+{
+ if (show_unhandled_signals && unhandled_signal(tsk, signo)
+ && printk_ratelimit()) {
+ pr_info("%s[%d]: unhandled signal %d code 0x%x at 0x" REG_FMT,
+ tsk->comm, task_pid_nr(tsk), signo, code, addr);
+ print_vma_addr(KERN_CONT " in ", GET_IP(regs));
+ pr_cont("\n");
+ show_regs(regs);
+ }
+
+ do_trap_siginfo(signo, code, addr, tsk);
+}
+
+static void do_trap_error(struct pt_regs *regs, int signo, int code,
+ unsigned long addr, const char *str)
+{
+ if (user_mode(regs)) {
+ do_trap(regs, signo, code, addr, current);
+ } else {
+ if (!fixup_exception(regs))
+ die(regs, str);
+ }
+}
+
+#define DO_ERROR_INFO(name, signo, code, str) \
+asmlinkage void name(struct pt_regs *regs) \
+{ \
+ do_trap_error(regs, signo, code, regs->sepc, "Oops - " str); \
+}
+
+DO_ERROR_INFO(do_trap_unknown,
+ SIGILL, ILL_ILLTRP, "unknown exception");
+DO_ERROR_INFO(do_trap_insn_misaligned,
+ SIGBUS, BUS_ADRALN, "instruction address misaligned");
+DO_ERROR_INFO(do_trap_insn_fault,
+ SIGBUS, BUS_ADRALN, "instruction access fault");
+DO_ERROR_INFO(do_trap_insn_illegal,
+ SIGILL, ILL_ILLOPC, "illegal instruction");
+DO_ERROR_INFO(do_trap_load_misaligned,
+ SIGBUS, BUS_ADRALN, "load address misaligned");
+DO_ERROR_INFO(do_trap_load_fault,
+ SIGSEGV, SEGV_ACCERR, "load access fault");
+DO_ERROR_INFO(do_trap_store_misaligned,
+ SIGBUS, BUS_ADRALN, "store (or AMO) address misaligned");
+DO_ERROR_INFO(do_trap_store_fault,
+ SIGSEGV, SEGV_ACCERR, "store (or AMO) access fault");
+DO_ERROR_INFO(do_trap_ecall_u,
+ SIGILL, ILL_ILLTRP, "environment call from U-mode");
+DO_ERROR_INFO(do_trap_ecall_s,
+ SIGILL, ILL_ILLTRP, "environment call from S-mode");
+DO_ERROR_INFO(do_trap_ecall_m,
+ SIGILL, ILL_ILLTRP, "environment call from M-mode");
+
+asmlinkage void do_trap_break(struct pt_regs *regs)
+{
+#ifdef CONFIG_GENERIC_BUG
+ if (!user_mode(regs)) {
+ enum bug_trap_type type;
+
+ type = report_bug(regs->sepc, regs);
+ switch (type) {
+ case BUG_TRAP_TYPE_NONE:
+ break;
+ case BUG_TRAP_TYPE_WARN:
+ regs->sepc += sizeof(bug_insn_t);
+ return;
+ case BUG_TRAP_TYPE_BUG:
+ die(regs, "Kernel BUG");
+ }
+ }
+#endif /* CONFIG_GENERIC_BUG */
+
+ do_trap_siginfo(SIGTRAP, TRAP_BRKPT, regs->sepc, current);
+ regs->sepc += 0x4;
+}
+
+#ifdef CONFIG_GENERIC_BUG
+int is_valid_bugaddr(unsigned long pc)
+{
+ bug_insn_t insn;
+
+ if (pc < PAGE_OFFSET)
+ return 0;
+ if (probe_kernel_address((bug_insn_t __user *)pc, insn))
+ return 0;
+ return (insn == __BUG_INSN);
+}
+#endif /* CONFIG_GENERIC_BUG */
+
+void __init trap_init(void)
+{
+ int hart = smp_processor_id();
+
+ /* Set sup0 scratch register to 0, indicating to exception vector
+ * that we are presently executing in the kernel
+ */
+ csr_write(sscratch, 0);
+ /* Set the exception vector address */
+ csr_write(stvec, &handle_exception);
+ /* Enable software interrupts and setup initial mask */
+ csr_write(sie,
+ SIE_SSIE | atomic_long_read(&per_cpu(riscv_early_sie, hart))
+ );
+}
diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
new file mode 100644
index 000000000000..e8a178df8144
--- /dev/null
+++ b/arch/riscv/kernel/vdso.c
@@ -0,0 +1,125 @@
+/*
+ * Copyright (C) 2004 Benjamin Herrenschmidt, IBM Corp.
+ * <benh@xxxxxxxxxxxxxxxxxxx>
+ * Copyright (C) 2012 ARM Limited
+ * Copyright (C) 2015 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/binfmts.h>
+#include <linux/err.h>
+
+#include <asm/vdso.h>
+
+extern char vdso_start[], vdso_end[];
+
+static unsigned int vdso_pages;
+static struct page **vdso_pagelist;
+
+/*
+ * The vDSO data page.
+ */
+static union {
+ struct vdso_data data;
+ u8 page[PAGE_SIZE];
+} vdso_data_store __page_aligned_data;
+struct vdso_data *vdso_data = &vdso_data_store.data;
+
+static int __init vdso_init(void)
+{
+ unsigned int i;
+
+ vdso_pages = (vdso_end - vdso_start) >> PAGE_SHIFT;
+ vdso_pagelist =
+ kcalloc(vdso_pages + 1, sizeof(struct page *), GFP_KERNEL);
+ if (unlikely(vdso_pagelist == NULL)) {
+ pr_err("vdso: pagelist allocation failed\n");
+ return -ENOMEM;
+ }
+
+ for (i = 0; i < vdso_pages; i++) {
+ struct page *pg;
+
+ pg = virt_to_page(vdso_start + (i << PAGE_SHIFT));
+ ClearPageReserved(pg);
+ vdso_pagelist[i] = pg;
+ }
+ vdso_pagelist[i] = virt_to_page(vdso_data);
+
+ return 0;
+}
+arch_initcall(vdso_init);
+
+int arch_setup_additional_pages(struct linux_binprm *bprm,
+ int uses_interp)
+{
+ struct mm_struct *mm = current->mm;
+ unsigned long vdso_base, vdso_len;
+ int ret;
+
+ vdso_len = (vdso_pages + 1) << PAGE_SHIFT;
+
+ down_write(&mm->mmap_sem);
+ vdso_base = get_unmapped_area(NULL, 0, vdso_len, 0, 0);
+ if (unlikely(IS_ERR_VALUE(vdso_base))) {
+ ret = vdso_base;
+ goto end;
+ }
+
+ /*
+ * Put vDSO base into mm struct. We need to do this before calling
+ * install_special_mapping or the perf counter mmap tracking code
+ * will fail to recognise it as a vDSO (since arch_vma_name fails).
+ */
+ mm->context.vdso = (void *)vdso_base;
+
+ ret = install_special_mapping(mm, vdso_base, vdso_len,
+ (VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC),
+ vdso_pagelist);
+
+ if (unlikely(ret))
+ mm->context.vdso = NULL;
+
+end:
+ up_write(&mm->mmap_sem);
+ return ret;
+}
+
+const char *arch_vma_name(struct vm_area_struct *vma)
+{
+ if (vma->vm_mm && (vma->vm_start == (long)vma->vm_mm->context.vdso))
+ return "[vdso]";
+ return NULL;
+}
+
+/*
+ * Function stubs to prevent linker errors when AT_SYSINFO_EHDR is defined
+ */
+
+int in_gate_area_no_mm(unsigned long addr)
+{
+ return 0;
+}
+
+int in_gate_area(struct mm_struct *mm, unsigned long addr)
+{
+ return 0;
+}
+
+struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
+{
+ return NULL;
+}
diff --git a/arch/riscv/kernel/vdso/.gitignore b/arch/riscv/kernel/vdso/.gitignore
new file mode 100644
index 000000000000..f8b69d84238e
--- /dev/null
+++ b/arch/riscv/kernel/vdso/.gitignore
@@ -0,0 +1 @@
+vdso.lds
diff --git a/arch/riscv/kernel/vdso/Makefile b/arch/riscv/kernel/vdso/Makefile
new file mode 100644
index 000000000000..04f3ec75b217
--- /dev/null
+++ b/arch/riscv/kernel/vdso/Makefile
@@ -0,0 +1,61 @@
+# Derived from arch/{arm64,tile}/kernel/vdso/Makefile
+
+obj-vdso := sigreturn.o
+
+# Build rules
+targets := $(obj-vdso) vdso.so vdso.so.dbg
+obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
+
+#ccflags-y := -shared -fno-common -fno-builtin
+#ccflags-y += -nostdlib -Wl,-soname=linux-vdso.so.1 \
+ $(call cc-ldoption, -Wl$(comma)--hash-style=sysv)
+
+CFLAGS_vdso.so = $(c_flags)
+CFLAGS_vdso.so.dbg = -shared -s -Wl,-soname=linux-vdso.so.1 \
+ $(call cc-ldoption, -Wl$(comma)--hash-style=sysv)
+CFLAGS_vdso_syms.o = -r
+
+obj-y += vdso.o
+
+# We also create a special relocatable object that should mirror the symbol
+# table and layout of the linked DSO. With ld -R we can then refer to
+# these symbols in the kernel code rather than hand-coded addresses.
+extra-y += vdso.lds vdso-syms.o
+$(obj)/built-in.o: $(obj)/vdso-syms.o
+$(obj)/built-in.o: ld_flags += -R $(obj)/vdso-syms.o
+
+CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
+
+# Force dependency
+$(obj)/vdso.o : $(obj)/vdso.so
+
+# Link rule for the *.so file; *.lds must be first
+$(obj)/vdso.so.dbg: $(src)/vdso.lds $(obj-vdso)
+ $(call if_changed,vdsold)
+$(obj)/vdso-syms.o: $(src)/vdso.lds $(obj-vdso)
+ $(call if_changed,vdsold)
+
+# Strip rule for the *.so file
+$(obj)/%.so: OBJCOPYFLAGS := -S
+$(obj)/%.so: $(obj)/%.so.dbg FORCE
+ $(call if_changed,objcopy)
+
+# Assembly rules for the *.S files
+$(obj-vdso): %.o: %.S
+ $(call if_changed_dep,vdsoas)
+
+# Actual build commands
+quiet_cmd_vdsold = VDSOLD $@
+ cmd_vdsold = $(CC) $(c_flags) -nostdlib $(CFLAGS_$(@F)) -Wl,-n -Wl,-T $^ -o $@
+quiet_cmd_vdsoas = VDSOAS $@
+ cmd_vdsoas = $(CC) $(a_flags) -c -o $@ $<
+
+# Install commands for the unstripped file
+quiet_cmd_vdso_install = INSTALL $@
+ cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
+
+vdso.so: $(obj)/vdso.so.dbg
+ @mkdir -p $(MODLIB)/vdso
+ $(call cmd,vdso_install)
+
+vdso_install: vdso.so
diff --git a/arch/riscv/kernel/vdso/sigreturn.S b/arch/riscv/kernel/vdso/sigreturn.S
new file mode 100644
index 000000000000..f5aa3d72acfb
--- /dev/null
+++ b/arch/riscv/kernel/vdso/sigreturn.S
@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2014 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/linkage.h>
+#include <asm/unistd.h>
+
+ .text
+ENTRY(__vdso_rt_sigreturn)
+ .cfi_startproc
+ .cfi_signal_frame
+ li a7, __NR_rt_sigreturn
+ scall
+ .cfi_endproc
+ENDPROC(__vdso_rt_sigreturn)
diff --git a/arch/riscv/kernel/vdso/vdso.S b/arch/riscv/kernel/vdso/vdso.S
new file mode 100644
index 000000000000..7055de5f9174
--- /dev/null
+++ b/arch/riscv/kernel/vdso/vdso.S
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2014 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/init.h>
+#include <linux/linkage.h>
+#include <asm/page.h>
+
+ __PAGE_ALIGNED_DATA
+
+ .globl vdso_start, vdso_end
+ .balign PAGE_SIZE
+vdso_start:
+ .incbin "arch/riscv/kernel/vdso/vdso.so"
+ .balign PAGE_SIZE
+vdso_end:
+
+ .previous
diff --git a/arch/riscv/kernel/vdso/vdso.lds.S b/arch/riscv/kernel/vdso/vdso.lds.S
new file mode 100644
index 000000000000..24942cb25694
--- /dev/null
+++ b/arch/riscv/kernel/vdso/vdso.lds.S
@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+OUTPUT_ARCH(riscv)
+
+SECTIONS
+{
+ . = SIZEOF_HEADERS;
+
+ .hash : { *(.hash) } :text
+ .gnu.hash : { *(.gnu.hash) }
+ .dynsym : { *(.dynsym) }
+ .dynstr : { *(.dynstr) }
+ .gnu.version : { *(.gnu.version) }
+ .gnu.version_d : { *(.gnu.version_d) }
+ .gnu.version_r : { *(.gnu.version_r) }
+
+ .note : { *(.note.*) } :text :note
+ .dynamic : { *(.dynamic) } :text :dynamic
+
+ .eh_frame_hdr : { *(.eh_frame_hdr) } :text :eh_frame_hdr
+ .eh_frame : { KEEP (*(.eh_frame)) } :text
+
+ .rodata : { *(.rodata .rodata.* .gnu.linkonce.r.*) }
+
+ /*
+ * This linker script is used both with -r and with -shared.
+ * For the layouts to match, we need to skip more than enough
+ * space for the dynamic symbol table, etc. If this amount is
+ * insufficient, ld -shared will error; simply increase it here.
+ */
+ . = 0x800;
+ .text : { *(.text .text.*) } :text
+
+ .data : {
+ *(.got.plt) *(.got)
+ *(.data .data.* .gnu.linkonce.d.*)
+ *(.dynbss)
+ *(.bss .bss.* .gnu.linkonce.b.*)
+ }
+}
+
+/*
+ * We must supply the ELF program headers explicitly to get just one
+ * PT_LOAD segment, and set the flags explicitly to make segments read-only.
+ */
+PHDRS
+{
+ text PT_LOAD FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */
+ dynamic PT_DYNAMIC FLAGS(4); /* PF_R */
+ note PT_NOTE FLAGS(4); /* PF_R */
+ eh_frame_hdr PT_GNU_EH_FRAME;
+}
+
+/*
+ * This controls what symbols we export from the DSO.
+ */
+VERSION
+{
+ LINUX_2.6 {
+ global:
+ __vdso_rt_sigreturn;
+ local: *;
+ };
+}
+
diff --git a/arch/riscv/kernel/vmlinux.lds.S b/arch/riscv/kernel/vmlinux.lds.S
new file mode 100644
index 000000000000..ece84991609c
--- /dev/null
+++ b/arch/riscv/kernel/vmlinux.lds.S
@@ -0,0 +1,92 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#define LOAD_OFFSET PAGE_OFFSET
+#include <asm/vmlinux.lds.h>
+#include <asm/page.h>
+#include <asm/cache.h>
+#include <asm/thread_info.h>
+
+OUTPUT_ARCH(riscv)
+ENTRY(_start)
+
+jiffies = jiffies_64;
+
+SECTIONS
+{
+ /* Beginning of code and text segment */
+ . = LOAD_OFFSET;
+ _start = .;
+ __init_begin = .;
+ HEAD_TEXT_SECTION
+ INIT_TEXT_SECTION(PAGE_SIZE)
+ INIT_DATA_SECTION(16)
+ /* we have to discard exit text and such at runtime, not link time */
+ .exit.text :
+ {
+ EXIT_TEXT
+ }
+ .exit.data :
+ {
+ EXIT_DATA
+ }
+ PERCPU_SECTION(L1_CACHE_BYTES)
+ __init_end = .;
+
+ .text : {
+ _text = .;
+ _stext = .;
+ TEXT_TEXT
+ SCHED_TEXT
+ CPUIDLE_TEXT
+ LOCK_TEXT
+ KPROBES_TEXT
+ ENTRY_TEXT
+ IRQENTRY_TEXT
+ *(.fixup)
+ _etext = .;
+ }
+
+ /* Start of data section */
+ _sdata = .;
+ RO_DATA_SECTION(L1_CACHE_BYTES)
+ .srodata : {
+ *(.srodata*)
+ }
+
+ RW_DATA_SECTION(L1_CACHE_BYTES, PAGE_SIZE, THREAD_SIZE)
+ .sdata : {
+ __global_pointer$ = . + 0x800;
+ *(.sdata*)
+ /* End of data section */
+ _edata = .;
+ *(.sbss*)
+ }
+
+ BSS_SECTION(0, 0, 0)
+
+ EXCEPTION_TABLE(0x10)
+ NOTES
+
+ .rel.dyn : {
+ *(.rel.dyn*)
+ }
+
+ _end = .;
+
+ STABS_DEBUG
+ DWARF_DEBUG
+
+ DISCARDS
+}
--
2.13.0
