diff options
author | Roman Kapl <rka@sysgo.com> | 2018-08-14 18:09:51 +0200 |
---|---|---|
committer | David Gibson <david@gibson.dropbear.id.au> | 2018-08-21 14:28:45 +1000 |
commit | 0e3bf4890906fa7066a5deafd6ab033934b8d100 (patch) | |
tree | c3374e5f373c86e74c668ac5c3bd8360e614cb9f /target/ppc/translate.c | |
parent | 2c88b098e76fde0c7fcc0476dd3f80ce58409505 (diff) |
ppc: add DBCR based debugging
Add support for DBCR (debug control register) based debugging as used on
BookE ppc. So far supports only branch and single-step events, but these are
the important ones. GDB in Linux guest can now do single-stepping.
Signed-off-by: Roman Kapl <rka@sysgo.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Diffstat (limited to 'target/ppc/translate.c')
-rw-r--r-- | target/ppc/translate.c | 107 |
1 files changed, 81 insertions, 26 deletions
diff --git a/target/ppc/translate.c b/target/ppc/translate.c index 9eaa10b421..881743571b 100644 --- a/target/ppc/translate.c +++ b/target/ppc/translate.c @@ -211,6 +211,7 @@ struct DisasContext { bool gtse; ppc_spr_t *spr_cb; /* Needed to check rights for mfspr/mtspr */ int singlestep_enabled; + uint32_t flags; uint64_t insns_flags; uint64_t insns_flags2; }; @@ -251,6 +252,17 @@ struct opc_handler_t { #endif }; +/* SPR load/store helpers */ +static inline void gen_load_spr(TCGv t, int reg) +{ + tcg_gen_ld_tl(t, cpu_env, offsetof(CPUPPCState, spr[reg])); +} + +static inline void gen_store_spr(int reg, TCGv t) +{ + tcg_gen_st_tl(t, cpu_env, offsetof(CPUPPCState, spr[reg])); +} + static inline void gen_set_access_type(DisasContext *ctx, int access_type) { if (ctx->need_access_type && ctx->access_type != access_type) { @@ -313,6 +325,38 @@ static void gen_exception_nip(DisasContext *ctx, uint32_t excp, ctx->exception = (excp); } +/* Translates the EXCP_TRACE/BRANCH exceptions used on most PowerPCs to + * EXCP_DEBUG, if we are running on cores using the debug enable bit (e.g. + * BookE). + */ +static uint32_t gen_prep_dbgex(DisasContext *ctx, uint32_t excp) +{ + if ((ctx->singlestep_enabled & CPU_SINGLE_STEP) + && (excp == POWERPC_EXCP_BRANCH)) { + /* Trace excpt. has priority */ + excp = POWERPC_EXCP_TRACE; + } + if (ctx->flags & POWERPC_FLAG_DE) { + target_ulong dbsr = 0; + switch (excp) { + case POWERPC_EXCP_TRACE: + dbsr = DBCR0_ICMP; + break; + case POWERPC_EXCP_BRANCH: + dbsr = DBCR0_BRT; + break; + } + TCGv t0 = tcg_temp_new(); + gen_load_spr(t0, SPR_BOOKE_DBSR); + tcg_gen_ori_tl(t0, t0, dbsr); + gen_store_spr(SPR_BOOKE_DBSR, t0); + tcg_temp_free(t0); + return POWERPC_EXCP_DEBUG; + } else { + return excp; + } +} + static void gen_debug_exception(DisasContext *ctx) { TCGv_i32 t0; @@ -575,17 +619,6 @@ typedef struct opcode_t { } #endif -/* SPR load/store helpers */ -static inline void gen_load_spr(TCGv t, int reg) -{ - tcg_gen_ld_tl(t, cpu_env, offsetof(CPUPPCState, spr[reg])); -} - -static inline void gen_store_spr(int reg, TCGv t) -{ - tcg_gen_st_tl(t, cpu_env, offsetof(CPUPPCState, spr[reg])); -} - /* Invalid instruction */ static void gen_invalid(DisasContext *ctx) { @@ -3602,6 +3635,24 @@ static inline bool use_goto_tb(DisasContext *ctx, target_ulong dest) #endif } +static void gen_lookup_and_goto_ptr(DisasContext *ctx) +{ + int sse = ctx->singlestep_enabled; + if (unlikely(sse)) { + if (sse & GDBSTUB_SINGLE_STEP) { + gen_debug_exception(ctx); + } else if (sse & (CPU_SINGLE_STEP | CPU_BRANCH_STEP)) { + uint32_t excp = gen_prep_dbgex(ctx, POWERPC_EXCP_BRANCH); + if (excp != POWERPC_EXCP_NONE) { + gen_exception(ctx, excp); + } + } + tcg_gen_exit_tb(NULL, 0); + } else { + tcg_gen_lookup_and_goto_ptr(); + } +} + /*** Branch ***/ static void gen_goto_tb(DisasContext *ctx, int n, target_ulong dest) { @@ -3614,18 +3665,7 @@ static void gen_goto_tb(DisasContext *ctx, int n, target_ulong dest) tcg_gen_exit_tb(ctx->base.tb, n); } else { tcg_gen_movi_tl(cpu_nip, dest & ~3); - if (unlikely(ctx->singlestep_enabled)) { - if ((ctx->singlestep_enabled & - (CPU_BRANCH_STEP | CPU_SINGLE_STEP)) && - (ctx->exception == POWERPC_EXCP_BRANCH || - ctx->exception == POWERPC_EXCP_TRACE)) { - gen_exception_nip(ctx, POWERPC_EXCP_TRACE, dest); - } - if (ctx->singlestep_enabled & GDBSTUB_SINGLE_STEP) { - gen_debug_exception(ctx); - } - } - tcg_gen_lookup_and_goto_ptr(); + gen_lookup_and_goto_ptr(ctx); } } @@ -3668,8 +3708,8 @@ static void gen_bcond(DisasContext *ctx, int type) uint32_t bo = BO(ctx->opcode); TCGLabel *l1; TCGv target; - ctx->exception = POWERPC_EXCP_BRANCH; + if (type == BCOND_LR || type == BCOND_CTR || type == BCOND_TAR) { target = tcg_temp_local_new(); if (type == BCOND_CTR) @@ -3733,10 +3773,11 @@ static void gen_bcond(DisasContext *ctx, int type) } else { tcg_gen_andi_tl(cpu_nip, target, ~3); } - tcg_gen_lookup_and_goto_ptr(); + gen_lookup_and_goto_ptr(ctx); tcg_temp_free(target); } if ((bo & 0x14) != 0x14) { + /* fallthrough case */ gen_set_label(l1); gen_goto_tb(ctx, 1, ctx->base.pc_next); } @@ -7419,6 +7460,7 @@ static void ppc_tr_init_disas_context(DisasContextBase *dcbase, CPUState *cs) ctx->need_access_type = !(env->mmu_model & POWERPC_MMU_64B); ctx->le_mode = !!(env->hflags & (1 << MSR_LE)); ctx->default_tcg_memop_mask = ctx->le_mode ? MO_LE : MO_BE; + ctx->flags = env->flags; #if defined(TARGET_PPC64) ctx->sf_mode = msr_is_64bit(env, env->msr); ctx->has_cfar = !!(env->flags & POWERPC_FLAG_CFAR); @@ -7455,6 +7497,17 @@ static void ppc_tr_init_disas_context(DisasContextBase *dcbase, CPUState *cs) ctx->singlestep_enabled = 0; if ((env->flags & POWERPC_FLAG_BE) && msr_be) ctx->singlestep_enabled |= CPU_BRANCH_STEP; + if ((env->flags & POWERPC_FLAG_DE) && msr_de) { + ctx->singlestep_enabled = 0; + target_ulong dbcr0 = env->spr[SPR_BOOKE_DBCR0]; + if (dbcr0 & DBCR0_ICMP) { + ctx->singlestep_enabled |= CPU_SINGLE_STEP; + } + if (dbcr0 & DBCR0_BRT) { + ctx->singlestep_enabled |= CPU_BRANCH_STEP; + } + + } if (unlikely(ctx->base.singlestep_enabled)) { ctx->singlestep_enabled |= GDBSTUB_SINGLE_STEP; } @@ -7565,7 +7618,9 @@ static void ppc_tr_translate_insn(DisasContextBase *dcbase, CPUState *cs) ctx->exception != POWERPC_SYSCALL && ctx->exception != POWERPC_EXCP_TRAP && ctx->exception != POWERPC_EXCP_BRANCH)) { - gen_exception_nip(ctx, POWERPC_EXCP_TRACE, ctx->base.pc_next); + uint32_t excp = gen_prep_dbgex(ctx, POWERPC_EXCP_TRACE); + if (excp != POWERPC_EXCP_NONE) + gen_exception_nip(ctx, excp, ctx->base.pc_next); } if (tcg_check_temp_count()) { |