From 53593e90d13264dc88b3281ddf75ceaa641df05a Mon Sep 17 00:00:00 2001 From: Max Filippov Date: Wed, 5 Dec 2012 07:15:23 +0400 Subject: target-xtensa: better control rsr/wsr/xsr access to SRs There are read-only (DEBUGCAUSE, PRID) and write-only (INTCLEAR) SRs, and INTERRUPT/INTSET SR allows rsr/wsr, but not xsr. Raise illeagal opcode exception on illegal access to these SRs. Signed-off-by: Max Filippov Signed-off-by: Blue Swirl --- target-xtensa/translate.c | 49 +++++++++++++++++++++++++++++------------------ 1 file changed, 30 insertions(+), 19 deletions(-) (limited to 'target-xtensa/translate.c') diff --git a/target-xtensa/translate.c b/target-xtensa/translate.c index 74b7b0f1aa..3303e5f693 100644 --- a/target-xtensa/translate.c +++ b/target-xtensa/translate.c @@ -81,16 +81,27 @@ static TCGv_i32 cpu_UR[256]; typedef struct XtensaReg { const char *name; uint64_t opt_bits; + enum { + SR_R = 1, + SR_W = 2, + SR_X = 4, + SR_RW = 3, + SR_RWX = 7, + } access; } XtensaReg; -#define XTENSA_REG(regname, opt) { \ +#define XTENSA_REG_ACCESS(regname, opt, acc) { \ .name = (regname), \ .opt_bits = XTENSA_OPTION_BIT(opt), \ + .access = (acc), \ } +#define XTENSA_REG(regname, opt) XTENSA_REG_ACCESS(regname, opt, SR_RWX) + #define XTENSA_REG_BITS(regname, opt) { \ .name = (regname), \ .opt_bits = (opt), \ + .access = SR_RWX, \ } static const XtensaReg sregnames[256] = { @@ -151,15 +162,15 @@ static const XtensaReg sregnames[256] = { [EXCSAVE1 + 6] = XTENSA_REG("EXCSAVE7", XTENSA_OPTION_HIGH_PRIORITY_INTERRUPT), [CPENABLE] = XTENSA_REG("CPENABLE", XTENSA_OPTION_COPROCESSOR), - [INTSET] = XTENSA_REG("INTSET", XTENSA_OPTION_INTERRUPT), - [INTCLEAR] = XTENSA_REG("INTCLEAR", XTENSA_OPTION_INTERRUPT), + [INTSET] = XTENSA_REG_ACCESS("INTSET", XTENSA_OPTION_INTERRUPT, SR_RW), + [INTCLEAR] = XTENSA_REG_ACCESS("INTCLEAR", XTENSA_OPTION_INTERRUPT, SR_W), [INTENABLE] = XTENSA_REG("INTENABLE", XTENSA_OPTION_INTERRUPT), [PS] = XTENSA_REG_BITS("PS", XTENSA_OPTION_ALL), [VECBASE] = XTENSA_REG("VECBASE", XTENSA_OPTION_RELOCATABLE_VECTOR), [EXCCAUSE] = XTENSA_REG("EXCCAUSE", XTENSA_OPTION_EXCEPTION), - [DEBUGCAUSE] = XTENSA_REG("DEBUGCAUSE", XTENSA_OPTION_DEBUG), + [DEBUGCAUSE] = XTENSA_REG_ACCESS("DEBUGCAUSE", XTENSA_OPTION_DEBUG, SR_R), [CCOUNT] = XTENSA_REG("CCOUNT", XTENSA_OPTION_TIMER_INTERRUPT), - [PRID] = XTENSA_REG("PRID", XTENSA_OPTION_PROCESSOR_ID), + [PRID] = XTENSA_REG_ACCESS("PRID", XTENSA_OPTION_PROCESSOR_ID, SR_R), [ICOUNT] = XTENSA_REG("ICOUNT", XTENSA_OPTION_DEBUG), [ICOUNTLEVEL] = XTENSA_REG("ICOUNTLEVEL", XTENSA_OPTION_DEBUG), [EXCVADDR] = XTENSA_REG("EXCVADDR", XTENSA_OPTION_EXCEPTION), @@ -476,7 +487,7 @@ static void gen_brcondi(DisasContext *dc, TCGCond cond, tcg_temp_free(tmp); } -static void gen_check_sr(DisasContext *dc, uint32_t sr) +static void gen_check_sr(DisasContext *dc, uint32_t sr, unsigned access) { if (!xtensa_option_bits_enabled(dc->config, sregnames[sr].opt_bits)) { if (sregnames[sr].name) { @@ -485,6 +496,16 @@ static void gen_check_sr(DisasContext *dc, uint32_t sr) qemu_log("SR %d is not implemented\n", sr); } gen_exception_cause(dc, ILLEGAL_INSTRUCTION_CAUSE); + } else if (!(sregnames[sr].access & access)) { + static const char * const access_text[] = { + [SR_R] = "rsr", + [SR_W] = "wsr", + [SR_X] = "xsr", + }; + assert(access < ARRAY_SIZE(access_text) && access_text[access]); + qemu_log("SR %s is not available for %s\n", sregnames[sr].name, + access_text[access]); + gen_exception_cause(dc, ILLEGAL_INSTRUCTION_CAUSE); } } @@ -679,14 +700,6 @@ static void gen_wsr_ps(DisasContext *dc, uint32_t sr, TCGv_i32 v) gen_jumpi_check_loop_end(dc, -1); } -static void gen_wsr_debugcause(DisasContext *dc, uint32_t sr, TCGv_i32 v) -{ -} - -static void gen_wsr_prid(DisasContext *dc, uint32_t sr, TCGv_i32 v) -{ -} - static void gen_wsr_icount(DisasContext *dc, uint32_t sr, TCGv_i32 v) { if (dc->icount) { @@ -744,8 +757,6 @@ static void gen_wsr(DisasContext *dc, uint32_t sr, TCGv_i32 s) [INTCLEAR] = gen_wsr_intclear, [INTENABLE] = gen_wsr_intenable, [PS] = gen_wsr_ps, - [DEBUGCAUSE] = gen_wsr_debugcause, - [PRID] = gen_wsr_prid, [ICOUNT] = gen_wsr_icount, [ICOUNTLEVEL] = gen_wsr_icountlevel, [CCOMPARE] = gen_wsr_ccompare, @@ -1467,7 +1478,7 @@ static void disas_xtensa_insn(CPUXtensaState *env, DisasContext *dc) case 6: /*XSR*/ { TCGv_i32 tmp = tcg_temp_new_i32(); - gen_check_sr(dc, RSR_SR); + gen_check_sr(dc, RSR_SR, SR_X); if (RSR_SR >= 64) { gen_check_privilege(dc); } @@ -1698,7 +1709,7 @@ static void disas_xtensa_insn(CPUXtensaState *env, DisasContext *dc) case 3: /*RST3*/ switch (OP2) { case 0: /*RSR*/ - gen_check_sr(dc, RSR_SR); + gen_check_sr(dc, RSR_SR, SR_R); if (RSR_SR >= 64) { gen_check_privilege(dc); } @@ -1707,7 +1718,7 @@ static void disas_xtensa_insn(CPUXtensaState *env, DisasContext *dc) break; case 1: /*WSR*/ - gen_check_sr(dc, RSR_SR); + gen_check_sr(dc, RSR_SR, SR_W); if (RSR_SR >= 64) { gen_check_privilege(dc); } -- cgit v1.2.1