Signed-off-by: Guo Ren <ren_guo@xxxxxxxxx>
---
arch/csky/include/asm/mmu_context.h | 140 ++++++++++++++++++++++++++++++++++
arch/csky/include/asm/processor.h | 140 ++++++++++++++++++++++++++++++++++
arch/csky/include/asm/thread_info.h | 77 +++++++++++++++++++
arch/csky/kernel/process.c | 147 ++++++++++++++++++++++++++++++++++++
arch/csky/kernel/time.c | 15 ++++
5 files changed, 519 insertions(+)
create mode 100644 arch/csky/include/asm/mmu_context.h
create mode 100644 arch/csky/include/asm/processor.h
create mode 100644 arch/csky/include/asm/thread_info.h
create mode 100644 arch/csky/kernel/process.c
create mode 100644 arch/csky/kernel/time.c
diff --git a/arch/csky/include/asm/mmu_context.h b/arch/csky/include/asm/mmu_context.h
new file mode 100644
index 0000000..6eeea85
--- /dev/null
+++ b/arch/csky/include/asm/mmu_context.h
@@ -0,0 +1,140 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+#ifndef __ASM_CSKY_MMU_CONTEXT_H
+#define __ASM_CSKY_MMU_CONTEXT_H
+
+#include <asm-generic/mm_hooks.h>
+#include <asm/setup.h>
+#include <asm/page.h>
+#include <asm/cacheflush.h>
+#include <asm/tlbflush.h>
+
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <abi/ckmmu.h>
+
+/*
+ * For the fast tlb miss handlers, we currently keep a per cpu array
+ * of pointers to the current pgd for each processor. Also, the proc.
+ * id is stuffed into the context register. This should be changed to
+ * use the processor id via current->processor, where current is stored
+ * in watch hi/lo. The context register should be used to contiguously
+ * map the page tables.
+ */
+#define TLBMISS_HANDLER_SETUP_PGD(pgd) tlbmiss_handler_setup_pgd((unsigned long)pgd)
+
+#define cpu_context(cpu, mm) ((mm)->context.asid[cpu])
+#define cpu_asid(cpu, mm) (cpu_context((cpu), (mm)) & ASID_MASK)
+#define asid_cache(cpu) (cpu_data[cpu].asid_cache)
+
+#define ASID_INC 0x1
+#define ASID_MASK 0xff
+#define ASID_VERSION_MASK 0xffffff00
+#define ASID_FIRST_VERSION 0x100
+
+#define destroy_context(mm) do{}while(0)
+#define enter_lazy_tlb(mm,tsk) do{}while(0)
+#define deactivate_mm(tsk,mm) do{}while(0)
+
+/*
+ * All unused by hardware upper bits will be considered
+ * as a software asid extension.
+ */
+static inline void
+get_new_mmu_context(struct mm_struct *mm, unsigned long cpu)
+{
+ unsigned long asid = asid_cache(cpu);
+
+ if (! ((asid += ASID_INC) & ASID_MASK) ) {
+ flush_tlb_all(); /* start new asid cycle */
+ if (!asid) /* fix version if needed */
+ asid = ASID_FIRST_VERSION;
+ }
+ cpu_context(cpu, mm) = asid_cache(cpu) = asid;
+}
+
+/*
+ * Initialize the context related info for a new mm_struct
+ * instance.
+ */
+static inline int
+init_new_context(struct task_struct *tsk, struct mm_struct *mm)
+{
+ int i;
+
+ for_each_online_cpu(i)
+ cpu_context(i, mm) = 0;
+ return 0;
+}
+
+static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
+ struct task_struct *tsk)
+{
+ unsigned int cpu = smp_processor_id();
+ unsigned long flags;
+
+ local_irq_save(flags);
+ /* Check if our ASID is of an older version and thus invalid */
+ if ((cpu_context(cpu, next) ^ asid_cache(cpu)) & ASID_VERSION_MASK)
+ get_new_mmu_context(next, cpu);
+ write_mmu_entryhi(cpu_context(cpu, next));
+ TLBMISS_HANDLER_SETUP_PGD(next->pgd);
+
+ /*
+ * Mark current->active_mm as not "active" anymore.
+ * We don't want to mislead possible IPI tlb flush routines.
+ */
+ cpumask_clear_cpu(cpu, mm_cpumask(prev));
+ cpumask_set_cpu(cpu, mm_cpumask(next));
+
+ local_irq_restore(flags);
+}
+
+/*
+ * After we have set current->mm to a new value, this activates
+ * the context for the new mm so we see the new mappings.
+ */
+static inline void
+activate_mm(struct mm_struct *prev, struct mm_struct *next)
+{
+ unsigned long flags;
+ int cpu = smp_processor_id();
+
+ local_irq_save(flags);
+
+ /* Unconditionally get a new ASID. */
+ get_new_mmu_context(next, cpu);
+
+ write_mmu_entryhi(cpu_context(cpu, next));
+ TLBMISS_HANDLER_SETUP_PGD(next->pgd);
+
+ /* mark mmu ownership change */
+ cpumask_clear_cpu(cpu, mm_cpumask(prev));
+ cpumask_set_cpu(cpu, mm_cpumask(next));
+
+ local_irq_restore(flags);
+}
+
+/*
+ * If mm is currently active_mm, we can't really drop it. Instead,
+ * we will get a new one for it.
+ */
+static inline void
+drop_mmu_context(struct mm_struct *mm, unsigned cpu)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+
+ if (cpumask_test_cpu(cpu, mm_cpumask(mm))) {
+ get_new_mmu_context(mm, cpu);
+ write_mmu_entryhi(cpu_asid(cpu, mm));
+ } else {
+ /* will get a new context next time */
+ cpu_context(cpu, mm) = 0;
+ }
+
+ local_irq_restore(flags);
+}
+
+#endif /* __ASM_CSKY_MMU_CONTEXT_H */
diff --git a/arch/csky/include/asm/processor.h b/arch/csky/include/asm/processor.h
new file mode 100644
index 0000000..adebea7
--- /dev/null
+++ b/arch/csky/include/asm/processor.h
@@ -0,0 +1,140 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+#ifndef __ASM_CSKY_PROCESSOR_H
+#define __ASM_CSKY_PROCESSOR_H
+
+/*
+ * Default implementation of macro that returns current
+ * instruction pointer ("program counter").
+ */
+#define current_text_addr() ({ __label__ _l; _l: &&_l;})
+
+#include <linux/bitops.h>
+#include <asm/segment.h>
+#include <asm/ptrace.h>
+#include <asm/current.h>
+#include <asm/cache.h>
+#include <abi/regdef.h>
+#include <abi/reg_ops.h>
+#ifdef CONFIG_CPU_HAS_FPU
+#include <abi/fpu.h>
+#endif
+
+struct cpuinfo_csky {
+ unsigned long udelay_val;
+ unsigned long asid_cache;
+ /*
+ * Capability and feature descriptor structure for CSKY CPU
+ */
+ unsigned long options;
+ unsigned int processor_id[4];
+ unsigned int fpu_id;
+} __attribute__((aligned(SMP_CACHE_BYTES)));
+
+extern struct cpuinfo_csky cpu_data[];
+
+/*
+ * User space process size: 2GB. This is hardcoded into a few places,
+ * so don't change it unless you know what you are doing. TASK_SIZE
+ * for a 64 bit kernel expandable to 8192EB, of which the current CSKY
+ * implementations will "only" be able to use 1TB ...
+ */
+#define TASK_SIZE 0x7fff8000UL
+
+#ifdef __KERNEL__
+#define STACK_TOP TASK_SIZE
+#define STACK_TOP_MAX STACK_TOP
+#endif
+
+/* This decides where the kernel will search for a free chunk of vm
+ * space during mmap's.
+ */
+#define TASK_UNMAPPED_BASE (TASK_SIZE / 3)
+
+struct thread_struct {
+ unsigned long ksp; /* kernel stack pointer */
+ unsigned long usp; /* user stack pointer */
+ unsigned long sr; /* saved status register */
+ unsigned long esp0; /* points to SR of stack frame */
+ /* FPU regs */
+ unsigned long fcr; /* fpu control reg */
+ unsigned long fsr; /* fpu status reg, nothing in CPU_CSKYV2 */
+ unsigned long fesr; /* fpu exception status reg */
+ unsigned long fp[32]; /* fpu general regs.
+ In CPU_CSKYV1(FPU): 32 regs of 32 bits
+ fp[0] store fr0,
+ fp[1] store fr1...
+ In CPU_CSKYV2(VFP): 16 regs of 64 bits
+ fp[0] store vr0 low 32 bits,
+ fp[1] store vr0 high 32 bits... */
+
+ unsigned long hi;
+ unsigned long lo;
+ unsigned long dspcsr;
+
+ /* Other stuff associated with the thread. */
+ unsigned long address; /* Last user fault */
+ unsigned long error_code;
+ unsigned long trap_no;
+};
+
+#define INIT_THREAD { \
+ .ksp = (unsigned long) init_thread_union.stack + THREAD_SIZE, \
+ .sr = DEFAULT_PSR_VALUE, \
+}
+
+/*
+ * Do necessary setup to start up a newly executed thread.
+ *
+ * pass the data segment into user programs if it exists,
+ * it can't hurt anything as far as I can tell
+ */
+#define start_thread(_regs, _pc, _usp) \
+do { \
+ set_fs(USER_DS); /* reads from user space */ \
+ (_regs)->pc = (_pc); \
+ (_regs)->regs[1] = 0; /* ABIV1 is R7, uClibc_main rtdl arg */ \
+ (_regs)->regs[2] = 0; \
+ (_regs)->regs[3] = 0; /* ABIV2 is R7, use it? */ \
+ (_regs)->sr &= ~PS_S; \
+ wrusp(_usp); \
+} while(0)
+
+/* Forward declaration, a strange C thing */
+struct task_struct;
+
+/* Free all resources held by a thread. */
+static inline void release_thread(struct task_struct *dead_task)
+{
+}
+
+/* Prepare to copy thread state - unlazy all lazy status */
+#define prepare_to_copy(tsk) do { } while (0)
+
+extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
+
+#define copy_segments(tsk, mm) do { } while (0)
+#define release_segments(mm) do { } while (0)
+#define forget_segments() do { } while (0)
+
+extern unsigned long thread_saved_pc(struct task_struct *tsk);
+
+unsigned long get_wchan(struct task_struct *p);
+
+#define KSTK_EIP(tsk) \
+({ \
+ unsigned long eip = 0; \
+ if ((tsk)->thread.esp0 > PAGE_SIZE && \
+ MAP_NR((tsk)->thread.esp0) < max_mapnr) \
+ eip = ((struct pt_regs *) (tsk)->thread.esp0)->pc; \
+ eip; \
+})
+
+#define KSTK_ESP(tsk) ((tsk) == current ? rdusp() : (tsk)->thread.usp)
+
+#define task_pt_regs(p) \
+ ((struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1)
+
+#define cpu_relax() barrier()
+
+#endif /* __ASM_CSKY_PROCESSOR_H */
diff --git a/arch/csky/include/asm/thread_info.h b/arch/csky/include/asm/thread_info.h
new file mode 100644
index 0000000..af05d37
--- /dev/null
+++ b/arch/csky/include/asm/thread_info.h
@@ -0,0 +1,77 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+#ifndef _ASM_CSKY_THREAD_INFO_H
+#define _ASM_CSKY_THREAD_INFO_H
+
+#ifndef __ASSEMBLY__
+
+#include <asm/types.h>
+#include <asm/page.h>
+#include <abi/regdef.h>
+#include <asm/processor.h>
+
+struct thread_info {
+ struct task_struct *task;
+ void *dump_exec_domain;
+ unsigned long flags;
+ int preempt_count;
+ unsigned long tp_value;
+ mm_segment_t addr_limit;
+ struct restart_block restart_block;
+ struct pt_regs *regs;
+};
+
+#define INIT_THREAD_INFO(tsk) \
+{ \
+ .task = &tsk, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
+ .addr_limit = KERNEL_DS, \
+ .restart_block = { \
+ .fn = do_no_restart_syscall, \
+ }, \
+}
+
+#define THREAD_SIZE_ORDER (13 - PAGE_SHIFT)
+
+#ifdef COMPAT_KERNEL_4_9
+#define init_thread_info (init_thread_union.thread_info)
+#define init_stack (init_thread_union.stack)
+#endif
+
+static inline struct thread_info *current_thread_info(void)
+{
+ unsigned long sp;
+
+ asm volatile("mov %0, sp\n":"=r"(sp));
+
+ return (struct thread_info *)(sp & ~(THREAD_SIZE - 1));
+}
+
+#endif /* !__ASSEMBLY__ */
+
+/* entry.S relies on these definitions!
+ * bits 0-5 are tested at every exception exit
+ */
+#define TIF_SIGPENDING 0 /* signal pending */
+#define TIF_NOTIFY_RESUME 1 /* callback before returning to user */
+#define TIF_NEED_RESCHED 2 /* rescheduling necessary */
+#define TIF_SYSCALL_TRACE 5 /* syscall trace active */
+#define TIF_DELAYED_TRACE 14 /* single step a syscall */
+#define TIF_POLLING_NRFLAG 16 /* true if poll_idle() is polling TIF_NEED_RESCHED */
+#define TIF_MEMDIE 18 /* is terminating due to OOM killer */
+#define TIF_FREEZE 19 /* thread is freezing for suspend */
+#define TIF_RESTORE_SIGMASK 20 /* restore signal mask in do_signal() */
+#define TIF_SECCOMP 21 /* secure computing */
+
+#define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
+#define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME)
+#define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
+#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
+#define _TIF_DELAYED_TRACE (1 << TIF_DELAYED_TRACE)
+#define _TIF_POLLING_NRFLAG (1 << TIF_POLLING_NRFLAG)
+#define _TIF_MEMDIE (1 << TIF_MEMDIE)
+#define _TIF_FREEZE (1 << TIF_FREEZE)
+#define _TIF_RESTORE_SIGMASK (1 << TIF_RESTORE_SIGMASK)
+#define _TIF_SECCOMP (1 << TIF_SECCOMP)
+
+#endif /* _ASM_CSKY_THREAD_INFO_H */
diff --git a/arch/csky/kernel/process.c b/arch/csky/kernel/process.c
new file mode 100644
index 0000000..a7464a4
--- /dev/null
+++ b/arch/csky/kernel/process.c
@@ -0,0 +1,147 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+#include <linux/module.h>
+#include <linux/version.h>
+#include <linux/sched.h>
+#ifndef COMPAT_KERNEL_4_9
+#include <linux/sched/task_stack.h>
+#include <linux/sched/debug.h>
+#endif
+#include <linux/delay.h>
+#include <linux/kallsyms.h>
+#include <linux/uaccess.h>
+#include <asm/elf.h>
+#include <linux/ptrace.h>
+
+struct cpuinfo_csky cpu_data[NR_CPUS];
+
+asmlinkage void ret_from_fork(void);
+asmlinkage void ret_from_kernel_thread(void);
+
+/*
+ * Some archs flush debug and FPU info here
+ */
+void flush_thread(void){}
+
+/*
+ * Return saved PC from a blocked thread
+ */
+unsigned long thread_saved_pc(struct task_struct *tsk)
+{
+ struct switch_stack *sw = (struct switch_stack *)tsk->thread.ksp;
+
+ return sw->r15;
+}
+
+int copy_thread(unsigned long clone_flags,
+ unsigned long usp,
+ unsigned long kthread_arg,
+ struct task_struct *p)
+{
+ struct switch_stack * childstack;
+ unsigned long reg_psr = 0;
+ struct pt_regs *childregs = task_pt_regs(p);
+
+ preempt_disable();
+
+ asm volatile("mfcr %0, psr\n":"=r"(reg_psr));
+
+#ifdef CONFIG_CPU_HAS_FPU
+ save_fp_to_thread(p->thread.fp, &p->thread.fcr, &p->thread.fsr,
+ &p->thread.fesr);
+#endif
+#ifdef CONFIG_CPU_HAS_HILO
+ asm volatile(
+ "mfhi %0 \n"
+ "mflo %1 \n"
+ :"=r"(p->thread.hi),"=r"(p->thread.lo));
+#endif
+ preempt_enable();
+
+ childstack = ((struct switch_stack *) childregs) - 1;
+ memset(childstack, 0, sizeof(struct switch_stack));
+
+ /* setup ksp for switch_to !!! */
+ p->thread.ksp = (unsigned long)childstack;
+
+ if (unlikely(p->flags & PF_KTHREAD)) {
+ memset(childregs, 0, sizeof(struct pt_regs));
+ childstack->r15 = (unsigned long) ret_from_kernel_thread;
+ childstack->r8 = kthread_arg;
+ childstack->r9 = usp;
+ childregs->sr = reg_psr;
+
+ return 0;
+ } else {
+ *childregs = *(current_pt_regs());
+ childstack->r15 = (unsigned long) ret_from_fork;
+ }
+
+ /* Return 0 for subprocess when return from fork(),vfork(),clone() */
+ childregs->a0 = 0;
+
+ if (usp != 0)
+ p->thread.usp = usp;
+ else
+ p->thread.usp = rdusp();
+
+ if (clone_flags & CLONE_SETTLS) {
+ task_thread_info(p)->tp_value = (current_pt_regs())->regs[0];
+#ifdef __CSKYABIV2__
+ childregs->exregs[15] = task_thread_info(p)->tp_value;
+#endif
+ }
+
+ return 0;
+}
+
+/* Fill in the fpu structure for a core dump. */
+int dump_fpu (struct pt_regs *regs, struct user_cskyfp_struct *fpu)
+{
+ memcpy(fpu, ¤t->thread.fcr, sizeof(*fpu));
+ return 1;
+}
+EXPORT_SYMBOL(dump_fpu);
+
+int dump_task_regs(struct task_struct *tsk, elf_gregset_t *pr_regs)
+{
+ struct pt_regs *regs = (struct pt_regs *)(tsk->thread.esp0);
+
+ /* NOTE: usp is error value. */
+ ELF_CORE_COPY_REGS ((*pr_regs), regs)
+
+ /* Now fix usp in pr_regs, usp is in pr_regs[2] */
+#if defined(__CSKYABIV2__)
+ (*pr_regs)[16] = tsk->thread.usp;
+#else
+ (*pr_regs)[2] = tsk->thread.usp;
+#endif
+
+ return 1;
+}
+
+unsigned long get_wchan(struct task_struct *p)
+{
+ unsigned long esp, pc;
+ unsigned long stack_page;
+ int count = 0;
+ if (!p || p == current || p->state == TASK_RUNNING)
+ return 0;
+
+ stack_page = (unsigned long)p;
+ esp = p->thread.esp0;
+ do {
+ if (esp < stack_page+sizeof(struct task_struct) ||
+ esp >= 8184+stack_page)
+ return 0;
+ /*FIXME: There's may be error here!*/
+ pc = ((unsigned long *)esp)[1];
+ /* FIXME: This depends on the order of these functions. */
+ if (!in_sched_functions(pc))
+ return pc;
+ esp = *(unsigned long *) esp;
+ } while (count++ < 16);
+ return 0;
+}
+
+EXPORT_SYMBOL(get_wchan);
diff --git a/arch/csky/kernel/time.c b/arch/csky/kernel/time.c
new file mode 100644
index 0000000..4d9bc05
--- /dev/null
+++ b/arch/csky/kernel/time.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+#include <linux/clk-provider.h>
+#include <linux/clocksource.h>
+
+void __init time_init(void)
+{
+ of_clk_init(NULL);
+#ifdef COMPAT_KERNEL_4_9
+ clocksource_probe();
+#else
+ timer_probe();
+#endif
+}
+
--
2.7.4
