Add a SSE entry assembly code to handle SSE events. Events should be
registered with a struct sse_handler_arg containing a correct stack and
handler function.
Signed-off-by: Clément Léger <cleger@xxxxxxxxxxxx>
---
riscv/Makefile | 1 +
lib/riscv/asm/sse.h | 16 +++++++
lib/riscv/sse_entry.S | 100 ++++++++++++++++++++++++++++++++++++++++
lib/riscv/asm-offsets.c | 9 ++++
4 files changed, 126 insertions(+)
create mode 100644 lib/riscv/asm/sse.h
create mode 100644 lib/riscv/sse_entry.S
diff --git a/riscv/Makefile b/riscv/Makefile
index 919a3ebb..c7810359 100644
--- a/riscv/Makefile
+++ b/riscv/Makefile
@@ -37,6 +37,7 @@ cflatobjs += lib/riscv/processor.o
cflatobjs += lib/riscv/sbi.o
cflatobjs += lib/riscv/setup.o
cflatobjs += lib/riscv/smp.o
+cflatobjs += lib/riscv/sse_entry.o
cflatobjs += lib/riscv/stack.o
ifeq ($(ARCH),riscv32)
cflatobjs += lib/ldiv32.o
diff --git a/lib/riscv/asm/sse.h b/lib/riscv/asm/sse.h
new file mode 100644
index 00000000..557f6680
--- /dev/null
+++ b/lib/riscv/asm/sse.h
@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _ASMRISCV_SSE_H_
+#define _ASMRISCV_SSE_H_
+
+typedef void (*sse_handler_fn)(void *data, struct pt_regs *regs, unsigned int hartid);
+
+struct sse_handler_arg {
+ unsigned long reg_tmp;
+ sse_handler_fn handler;
+ void *handler_data;
+ void *stack;
+};
+
+extern void sse_entry(void);
+
+#endif /* _ASMRISCV_SSE_H_ */
diff --git a/lib/riscv/sse_entry.S b/lib/riscv/sse_entry.S
new file mode 100644
index 00000000..bedc47e9
--- /dev/null
+++ b/lib/riscv/sse_entry.S
@@ -0,0 +1,100 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * SBI SSE entry code
+ *
+ * Copyright (C) 2024, Rivos Inc., Clément Léger <cleger@xxxxxxxxxxxx>
+ */
+#include <asm/asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/csr.h>
+
+.global sse_entry
+sse_entry:
+ /* Save stack temporarily */
+ REG_S sp, SSE_REG_TMP(a6)
+ /* Set entry stack */
+ REG_L sp, SSE_HANDLER_STACK(a6)
+
+ addi sp, sp, -(PT_SIZE)
+ REG_S ra, PT_RA(sp)
+ REG_S s0, PT_S0(sp)
+ REG_S s1, PT_S1(sp)
+ REG_S s2, PT_S2(sp)
+ REG_S s3, PT_S3(sp)
+ REG_S s4, PT_S4(sp)
+ REG_S s5, PT_S5(sp)
+ REG_S s6, PT_S6(sp)
+ REG_S s7, PT_S7(sp)
+ REG_S s8, PT_S8(sp)
+ REG_S s9, PT_S9(sp)
+ REG_S s10, PT_S10(sp)
+ REG_S s11, PT_S11(sp)
+ REG_S tp, PT_TP(sp)
+ REG_S t0, PT_T0(sp)
+ REG_S t1, PT_T1(sp)
+ REG_S t2, PT_T2(sp)
+ REG_S t3, PT_T3(sp)
+ REG_S t4, PT_T4(sp)
+ REG_S t5, PT_T5(sp)
+ REG_S t6, PT_T6(sp)
+ REG_S gp, PT_GP(sp)
+ REG_S a0, PT_A0(sp)
+ REG_S a1, PT_A1(sp)
+ REG_S a2, PT_A2(sp)
+ REG_S a3, PT_A3(sp)
+ REG_S a4, PT_A4(sp)
+ REG_S a5, PT_A5(sp)
+ csrr a1, CSR_SEPC
+ REG_S a1, PT_EPC(sp)
+ csrr a2, CSR_SSTATUS
+ REG_S a2, PT_STATUS(sp)
+
+ REG_L a0, SSE_REG_TMP(a6)
+ REG_S a0, PT_SP(sp)
+
+ REG_L t0, SSE_HANDLER(a6)
+ REG_L a0, SSE_HANDLER_DATA(a6)
+ move a1, sp
+ move a2, a7
+ jalr t0
+
+
+ REG_L a1, PT_EPC(sp)
+ REG_L a2, PT_STATUS(sp)
+ csrw CSR_SEPC, a1
+ csrw CSR_SSTATUS, a2
+
+ REG_L ra, PT_RA(sp)
+ REG_L s0, PT_S0(sp)
+ REG_L s1, PT_S1(sp)
+ REG_L s2, PT_S2(sp)
+ REG_L s3, PT_S3(sp)
+ REG_L s4, PT_S4(sp)
+ REG_L s5, PT_S5(sp)
+ REG_L s6, PT_S6(sp)
+ REG_L s7, PT_S7(sp)
+ REG_L s8, PT_S8(sp)
+ REG_L s9, PT_S9(sp)
+ REG_L s10, PT_S10(sp)
+ REG_L s11, PT_S11(sp)
+ REG_L tp, PT_TP(sp)
+ REG_L t0, PT_T0(sp)
+ REG_L t1, PT_T1(sp)
+ REG_L t2, PT_T2(sp)
+ REG_L t3, PT_T3(sp)
+ REG_L t4, PT_T4(sp)
+ REG_L t5, PT_T5(sp)
+ REG_L t6, PT_T6(sp)
+ REG_L gp, PT_GP(sp)
+ 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 sp, PT_SP(sp)
+
+ li a7, ASM_SBI_EXT_SSE
+ li a6, ASM_SBI_EXT_SSE_COMPLETE
+ ecall
diff --git a/lib/riscv/asm-offsets.c b/lib/riscv/asm-offsets.c
index a2a32438..a5e25332 100644
--- a/lib/riscv/asm-offsets.c
+++ b/lib/riscv/asm-offsets.c
@@ -2,7 +2,9 @@
#include <kbuild.h>
#include <elf.h>
#include <asm/ptrace.h>
+#include <asm/sbi.h>
#include <asm/smp.h>
+#include <asm/sse.h>
int main(void)
{
@@ -58,5 +60,12 @@ int main(void)
OFFSET(SECONDARY_FUNC, secondary_data, func);
DEFINE(SECONDARY_DATA_SIZE, sizeof(struct secondary_data));
+ OFFSET(SSE_REG_TMP, sse_handler_arg, reg_tmp);
+ OFFSET(SSE_HANDLER, sse_handler_arg, handler);
+ OFFSET(SSE_HANDLER_DATA, sse_handler_arg, handler_data);
+ OFFSET(SSE_HANDLER_STACK, sse_handler_arg, stack);
+ DEFINE(ASM_SBI_EXT_SSE, SBI_EXT_SSE);
+ DEFINE(ASM_SBI_EXT_SSE_COMPLETE, SBI_EXT_SSE_COMPLETE);
+
return 0;
}
--
2.43.0
