From: Richard Henderson Date: Fri, 4 Jul 2025 14:19:39 +0000 (-0600) Subject: target/arm: Add zt0_excp_el to DisasContext X-Git-Tag: v10.1.0-rc0~29^2~91 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=3aad4bc8beb9a3a8c1ea3dc6ca9bfc85d3c7c8a4;p=thirdparty%2Fqemu.git target/arm: Add zt0_excp_el to DisasContext Pipe the value through from SMCR_ELx through hflags and into the disassembly context. Enable EZT0 in smcr_write. Reviewed-by: Peter Maydell Signed-off-by: Richard Henderson Message-id: 20250704142112.1018902-17-richard.henderson@linaro.org Signed-off-by: Peter Maydell --- diff --git a/target/arm/cpu.c b/target/arm/cpu.c index 62656277625..08c43f674a2 100644 --- a/target/arm/cpu.c +++ b/target/arm/cpu.c @@ -635,6 +635,9 @@ void arm_emulate_firmware_reset(CPUState *cpustate, int target_el) env->cp15.cptr_el[3] |= R_CPTR_EL3_ESM_MASK; env->cp15.scr_el3 |= SCR_ENTP2; env->vfp.smcr_el[3] = 0xf; + if (cpu_isar_feature(aa64_sme2, cpu)) { + env->vfp.smcr_el[3] |= R_SMCR_EZT0_MASK; + } } if (cpu_isar_feature(aa64_hcx, cpu)) { env->cp15.scr_el3 |= SCR_HXEN; diff --git a/target/arm/cpu.h b/target/arm/cpu.h index cbc20434836..39a9234ff28 100644 --- a/target/arm/cpu.h +++ b/target/arm/cpu.h @@ -1513,6 +1513,7 @@ FIELD(SVCR, ZA, 1, 1) /* Fields for SMCR_ELx. */ FIELD(SMCR, LEN, 0, 4) +FIELD(SMCR, EZT0, 30, 1) FIELD(SMCR, FA64, 31, 1) /* Write a new value to v7m.exception, thus transitioning into or out @@ -3084,6 +3085,7 @@ FIELD(TBFLAG_A64, NV2_MEM_E20, 35, 1) FIELD(TBFLAG_A64, NV2_MEM_BE, 36, 1) FIELD(TBFLAG_A64, AH, 37, 1) /* FPCR.AH */ FIELD(TBFLAG_A64, NEP, 38, 1) /* FPCR.NEP */ +FIELD(TBFLAG_A64, ZT0EXC_EL, 39, 2) /* * Helpers for using the above. Note that only the A64 accessors use diff --git a/target/arm/helper.c b/target/arm/helper.c index 3879bce8489..b3f0d6f17a8 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -6682,10 +6682,14 @@ static void smcr_write(CPUARMState *env, const ARMCPRegInfo *ri, { int cur_el = arm_current_el(env); int old_len = sve_vqm1_for_el(env, cur_el); + uint64_t valid_mask = R_SMCR_LEN_MASK | R_SMCR_FA64_MASK; int new_len; QEMU_BUILD_BUG_ON(ARM_MAX_VQ > R_SMCR_LEN_MASK + 1); - value &= R_SMCR_LEN_MASK | R_SMCR_FA64_MASK; + if (cpu_isar_feature(aa64_sme2, env_archcpu(env))) { + valid_mask |= R_SMCR_EZT0_MASK; + } + value &= valid_mask; raw_write(env, ri, value); /* diff --git a/target/arm/tcg/hflags.c b/target/arm/tcg/hflags.c index 1ccec63bbd4..59ab5263753 100644 --- a/target/arm/tcg/hflags.c +++ b/target/arm/tcg/hflags.c @@ -214,6 +214,31 @@ static CPUARMTBFlags rebuild_hflags_a32(CPUARMState *env, int fp_el, return rebuild_hflags_common_32(env, fp_el, mmu_idx, flags); } +/* + * Return the exception level to which exceptions should be taken for ZT0. + * C.f. the ARM pseudocode function CheckSMEZT0Enabled, after the ZA check. + */ +static int zt0_exception_el(CPUARMState *env, int el) +{ +#ifndef CONFIG_USER_ONLY + if (el <= 1 + && !el_is_in_host(env, el) + && !FIELD_EX64(env->vfp.smcr_el[1], SMCR, EZT0)) { + return 1; + } + if (el <= 2 + && arm_is_el2_enabled(env) + && !FIELD_EX64(env->vfp.smcr_el[2], SMCR, EZT0)) { + return 2; + } + if (arm_feature(env, ARM_FEATURE_EL3) + && !FIELD_EX64(env->vfp.smcr_el[3], SMCR, EZT0)) { + return 3; + } +#endif + return 0; +} + static CPUARMTBFlags rebuild_hflags_a64(CPUARMState *env, int el, int fp_el, ARMMMUIdx mmu_idx) { @@ -269,7 +294,14 @@ static CPUARMTBFlags rebuild_hflags_a64(CPUARMState *env, int el, int fp_el, DP_TBFLAG_A64(flags, PSTATE_SM, 1); DP_TBFLAG_A64(flags, SME_TRAP_NONSTREAMING, !sme_fa64(env, el)); } - DP_TBFLAG_A64(flags, PSTATE_ZA, FIELD_EX64(env->svcr, SVCR, ZA)); + + if (FIELD_EX64(env->svcr, SVCR, ZA)) { + DP_TBFLAG_A64(flags, PSTATE_ZA, 1); + if (cpu_isar_feature(aa64_sme2, env_archcpu(env))) { + int zt0_el = zt0_exception_el(env, el); + DP_TBFLAG_A64(flags, ZT0EXC_EL, zt0_el); + } + } } sctlr = regime_sctlr(env, stage1); diff --git a/target/arm/tcg/translate-a64.c b/target/arm/tcg/translate-a64.c index b0caccca46e..ad293c08858 100644 --- a/target/arm/tcg/translate-a64.c +++ b/target/arm/tcg/translate-a64.c @@ -10139,6 +10139,7 @@ static void aarch64_tr_init_disas_context(DisasContextBase *dcbase, dc->trap_eret = EX_TBFLAG_A64(tb_flags, TRAP_ERET); dc->sve_excp_el = EX_TBFLAG_A64(tb_flags, SVEEXC_EL); dc->sme_excp_el = EX_TBFLAG_A64(tb_flags, SMEEXC_EL); + dc->zt0_excp_el = EX_TBFLAG_A64(tb_flags, ZT0EXC_EL); dc->vl = (EX_TBFLAG_A64(tb_flags, VL) + 1) * 16; dc->svl = (EX_TBFLAG_A64(tb_flags, SVL) + 1) * 16; dc->pauth_active = EX_TBFLAG_A64(tb_flags, PAUTH_ACTIVE); diff --git a/target/arm/tcg/translate.h b/target/arm/tcg/translate.h index 0004a97219b..b03956a7937 100644 --- a/target/arm/tcg/translate.h +++ b/target/arm/tcg/translate.h @@ -70,6 +70,7 @@ typedef struct DisasContext { int fp_excp_el; /* FP exception EL or 0 if enabled */ int sve_excp_el; /* SVE exception EL or 0 if enabled */ int sme_excp_el; /* SME exception EL or 0 if enabled */ + int zt0_excp_el; /* ZT0 exception EL or 0 if enabled */ int vl; /* current vector length in bytes */ int svl; /* current streaming vector length in bytes */ bool vfp_enabled; /* FP enabled via FPSCR.EN */