From 3d8a952737935dd98200b05b68dacb5e94071877 Mon Sep 17 00:00:00 2001 From: Xiang W Date: Thu, 1 Apr 2021 15:59:40 +0800 Subject: [PATCH] lib: fix csr detect support csr_read_allowed/csr_read_allowed requires trap.case to detect the results, but if no exception occurs, the value of trap.case will remain unchanged, which makes the detection results unreliable. Add code to initialize trap.case to 0. Signed-off-by: Xiang W Reviewed-by: Anup Patel --- include/sbi/sbi_csr_detect.h | 3 +++ lib/sbi/sbi_hart.c | 3 --- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/include/sbi/sbi_csr_detect.h b/include/sbi/sbi_csr_detect.h index f2948884..89ba294a 100644 --- a/include/sbi/sbi_csr_detect.h +++ b/include/sbi/sbi_csr_detect.h @@ -12,6 +12,7 @@ #include #include +#include #define csr_read_allowed(csr_num, trap) \ ({ \ @@ -19,6 +20,7 @@ register ulong ttmp asm("a4"); \ register ulong mtvec = sbi_hart_expected_trap_addr(); \ register ulong ret = 0; \ + ((struct sbi_trap_info *)(trap))->cause = 0; \ asm volatile( \ "add %[ttmp], %[tinfo], zero\n" \ "csrrw %[mtvec], " STR(CSR_MTVEC) ", %[mtvec]\n" \ @@ -36,6 +38,7 @@ register ulong tinfo asm("a3") = (ulong)trap; \ register ulong ttmp asm("a4"); \ register ulong mtvec = sbi_hart_expected_trap_addr(); \ + ((struct sbi_trap_info *)(trap))->cause = 0; \ asm volatile( \ "add %[ttmp], %[tinfo], zero\n" \ "csrrw %[mtvec], " STR(CSR_MTVEC) ", %[mtvec]\n" \ diff --git a/lib/sbi/sbi_hart.c b/lib/sbi/sbi_hart.c index d91b08cf..de59b143 100644 --- a/lib/sbi/sbi_hart.c +++ b/lib/sbi/sbi_hart.c @@ -406,7 +406,6 @@ __mhpm_skip: #undef __check_csr /* Detect if hart supports SCOUNTEREN feature */ - trap.cause = 0; val = csr_read_allowed(CSR_SCOUNTEREN, (unsigned long)&trap); if (!trap.cause) { csr_write_allowed(CSR_SCOUNTEREN, (unsigned long)&trap, val); @@ -415,7 +414,6 @@ __mhpm_skip: } /* Detect if hart supports MCOUNTEREN feature */ - trap.cause = 0; val = csr_read_allowed(CSR_MCOUNTEREN, (unsigned long)&trap); if (!trap.cause) { csr_write_allowed(CSR_MCOUNTEREN, (unsigned long)&trap, val); @@ -424,7 +422,6 @@ __mhpm_skip: } /* Detect if hart supports time CSR */ - trap.cause = 0; csr_read_allowed(CSR_TIME, (unsigned long)&trap); if (!trap.cause) hfeatures->features |= SBI_HART_HAS_TIME;