From 753e3fe207db08ce0ef0405e8452c3397c9b9308 Mon Sep 17 00:00:00 2001 From: Jim Wilson Date: Fri, 15 Mar 2019 03:26:58 -0700 Subject: RISC-V: Add debug support for accessing CSRs. Add a debugger field to CPURISCVState. Add riscv_csrrw_debug function to set it. Disable mode checks when debugger field true. Signed-off-by: Jim Wilson Reviewed-by: Alistair Francis Message-Id: <20190212230903.9215-1-jimw@sifive.com> Signed-off-by: Palmer Dabbelt --- target/riscv/cpu.h | 5 +++++ target/riscv/csr.c | 32 +++++++++++++++++++++++++------- 2 files changed, 30 insertions(+), 7 deletions(-) (limited to 'target') diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h index 5c2aebf132..4c5de30b37 100644 --- a/target/riscv/cpu.h +++ b/target/riscv/cpu.h @@ -172,6 +172,9 @@ struct CPURISCVState { /* physical memory protection */ pmp_table_t pmp_state; + + /* True if in debugger mode. */ + bool debugger; #endif float_status fp_status; @@ -293,6 +296,8 @@ static inline void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc, int riscv_csrrw(CPURISCVState *env, int csrno, target_ulong *ret_value, target_ulong new_value, target_ulong write_mask); +int riscv_csrrw_debug(CPURISCVState *env, int csrno, target_ulong *ret_value, + target_ulong new_value, target_ulong write_mask); static inline void riscv_csr_write(CPURISCVState *env, int csrno, target_ulong val) diff --git a/target/riscv/csr.c b/target/riscv/csr.c index 960d2b0aa9..9a40b4c7ba 100644 --- a/target/riscv/csr.c +++ b/target/riscv/csr.c @@ -46,7 +46,7 @@ void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops) static int fs(CPURISCVState *env, int csrno) { #if !defined(CONFIG_USER_ONLY) - if (!(env->mstatus & MSTATUS_FS)) { + if (!env->debugger && !(env->mstatus & MSTATUS_FS)) { return -1; } #endif @@ -92,7 +92,7 @@ static int pmp(CPURISCVState *env, int csrno) static int read_fflags(CPURISCVState *env, int csrno, target_ulong *val) { #if !defined(CONFIG_USER_ONLY) - if (!(env->mstatus & MSTATUS_FS)) { + if (!env->debugger && !(env->mstatus & MSTATUS_FS)) { return -1; } #endif @@ -103,7 +103,7 @@ static int read_fflags(CPURISCVState *env, int csrno, target_ulong *val) static int write_fflags(CPURISCVState *env, int csrno, target_ulong val) { #if !defined(CONFIG_USER_ONLY) - if (!(env->mstatus & MSTATUS_FS)) { + if (!env->debugger && !(env->mstatus & MSTATUS_FS)) { return -1; } env->mstatus |= MSTATUS_FS; @@ -115,7 +115,7 @@ static int write_fflags(CPURISCVState *env, int csrno, target_ulong val) static int read_frm(CPURISCVState *env, int csrno, target_ulong *val) { #if !defined(CONFIG_USER_ONLY) - if (!(env->mstatus & MSTATUS_FS)) { + if (!env->debugger && !(env->mstatus & MSTATUS_FS)) { return -1; } #endif @@ -126,7 +126,7 @@ static int read_frm(CPURISCVState *env, int csrno, target_ulong *val) static int write_frm(CPURISCVState *env, int csrno, target_ulong val) { #if !defined(CONFIG_USER_ONLY) - if (!(env->mstatus & MSTATUS_FS)) { + if (!env->debugger && !(env->mstatus & MSTATUS_FS)) { return -1; } env->mstatus |= MSTATUS_FS; @@ -138,7 +138,7 @@ static int write_frm(CPURISCVState *env, int csrno, target_ulong val) static int read_fcsr(CPURISCVState *env, int csrno, target_ulong *val) { #if !defined(CONFIG_USER_ONLY) - if (!(env->mstatus & MSTATUS_FS)) { + if (!env->debugger && !(env->mstatus & MSTATUS_FS)) { return -1; } #endif @@ -150,7 +150,7 @@ static int read_fcsr(CPURISCVState *env, int csrno, target_ulong *val) static int write_fcsr(CPURISCVState *env, int csrno, target_ulong val) { #if !defined(CONFIG_USER_ONLY) - if (!(env->mstatus & MSTATUS_FS)) { + if (!env->debugger && !(env->mstatus & MSTATUS_FS)) { return -1; } env->mstatus |= MSTATUS_FS; @@ -827,6 +827,24 @@ int riscv_csrrw(CPURISCVState *env, int csrno, target_ulong *ret_value, return 0; } +/* + * Debugger support. If not in user mode, set env->debugger before the + * riscv_csrrw call and clear it after the call. + */ +int riscv_csrrw_debug(CPURISCVState *env, int csrno, target_ulong *ret_value, + target_ulong new_value, target_ulong write_mask) +{ + int ret; +#if !defined(CONFIG_USER_ONLY) + env->debugger = true; +#endif + ret = riscv_csrrw(env, csrno, ret_value, new_value, write_mask); +#if !defined(CONFIG_USER_ONLY) + env->debugger = false; +#endif + return ret; +} + /* Control and Status Register function table */ static riscv_csr_operations csr_ops[CSR_TABLE_SIZE] = { /* User Floating-Point CSRs */ -- cgit v1.2.3