Support sdcause

Signed-off-by: Alan Kao <alankao@andestech.com>

Author: NonerKao

arch/riscv/include/asm/csr.h

@@ -89,6 +89,7 @@
 #define CSR_CYCLEH		0xc80
 #define CSR_TIMEH		0xc81
 #define CSR_INSTRETH		0xc82
+#define CSR_SDCAUSE		0x9c9
 
 /* IE/IP (Supervisor/Machine Interrupt Enable/Pending) flags */
 #define IE_SIE         (_AC(0x1, UL) << IRQ_S_SOFT)

arch/riscv/include/asm/ptrace.h

@@ -48,6 +48,7 @@ struct pt_regs {
 	unsigned long sstatus;
 	unsigned long sbadaddr;
 	unsigned long scause;
+	unsigned long sdcause;
 	/* a0 value before the syscall */
 	unsigned long orig_a0;
 };

arch/riscv/kernel/asm-offsets.c

@@ -108,6 +108,7 @@ void asm_offsets(void)
 	OFFSET(PT_SSTATUS, pt_regs, sstatus);
 	OFFSET(PT_SBADADDR, pt_regs, sbadaddr);
 	OFFSET(PT_SCAUSE, pt_regs, scause);
+	OFFSET(PT_SDCAUSE, pt_regs, sdcause);
 
 	/*
 	 * THREAD_{F,X}* might be larger than a S-type offset can handle, but

arch/riscv/kernel/entry.S

@@ -84,12 +84,14 @@ _save_context:
 	csrr s3, CSR_STVAL
 	csrr s4, CSR_SCAUSE
 	csrr s5, CSR_SSCRATCH
+	csrr s5, CSR_SDCAUSE
 	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)
+	REG_S s6, PT_SDCAUSE(sp)
 	.endm
 
 /*

arch/riscv/kernel/process.c

@@ -58,8 +58,8 @@ void show_regs(struct pt_regs *regs)
 	pr_cont(" t5 : " REG_FMT " t6 : " REG_FMT "\n",
 		regs->t5, regs->t6);
 
-	pr_cont("sstatus: " REG_FMT " sbadaddr: " REG_FMT " scause: " REG_FMT "\n",
-		regs->sstatus, regs->sbadaddr, regs->scause);
+	pr_cont("sstatus: " REG_FMT " sbadaddr: " REG_FMT " scause: " REG_FMT " sdcause: " REG_FMT "\n",
+		regs->sstatus, regs->sbadaddr, regs->scause, regs->sdcause);
 }
 
 void start_thread(struct pt_regs *regs, unsigned long pc,