diff --git a/target-mips/cpu.h b/target-mips/cpu.h index 7285636b68..c21b8e43ff 100644 --- a/target-mips/cpu.h +++ b/target-mips/cpu.h @@ -363,6 +363,7 @@ struct CPUMIPSState { #define CP0C2_SA 0 int32_t CP0_Config3; #define CP0C3_M 31 +#define CP0C3_ISA_ON_EXC 16 #define CP0C3_DSPP 10 #define CP0C3_LPA 7 #define CP0C3_VEIC 6 diff --git a/target-mips/helper.c b/target-mips/helper.c index 8102f03c26..ea221ab53f 100644 --- a/target-mips/helper.c +++ b/target-mips/helper.c @@ -385,6 +385,18 @@ static target_ulong exception_resume_pc (CPUState *env) return bad_pc; } + +static void set_hflags_for_handler (CPUState *env) +{ + /* Exception handlers are entered in 32-bit mode. */ + env->hflags &= ~(MIPS_HFLAG_M16); + /* ...except that microMIPS lets you choose. */ + if (env->insn_flags & ASE_MICROMIPS) { + env->hflags |= (!!(env->CP0_Config3 + & (1 << CP0C3_ISA_ON_EXC)) + << MIPS_HFLAG_M16_SHIFT); + } +} #endif void do_interrupt (CPUState *env) @@ -440,8 +452,7 @@ void do_interrupt (CPUState *env) if (!(env->CP0_Status & (1 << CP0St_EXL))) env->CP0_Cause &= ~(1 << CP0Ca_BD); env->active_tc.PC = (int32_t)0xBFC00480; - /* Exception handlers are entered in 32-bit mode. */ - env->hflags &= ~(MIPS_HFLAG_M16); + set_hflags_for_handler(env); break; case EXCP_RESET: cpu_reset(env); @@ -461,8 +472,7 @@ void do_interrupt (CPUState *env) if (!(env->CP0_Status & (1 << CP0St_EXL))) env->CP0_Cause &= ~(1 << CP0Ca_BD); env->active_tc.PC = (int32_t)0xBFC00000; - /* Exception handlers are entered in 32-bit mode. */ - env->hflags &= ~(MIPS_HFLAG_M16); + set_hflags_for_handler(env); break; case EXCP_EXT_INTERRUPT: cause = 0; @@ -581,8 +591,7 @@ void do_interrupt (CPUState *env) env->active_tc.PC = (int32_t)(env->CP0_EBase & ~0x3ff); } env->active_tc.PC += offset; - /* Exception handlers are entered in 32-bit mode. */ - env->hflags &= ~(MIPS_HFLAG_M16); + set_hflags_for_handler(env); env->CP0_Cause = (env->CP0_Cause & ~(0x1f << CP0Ca_EC)) | (cause << CP0Ca_EC); break; default: