From e4c93e44ab103f6c67abd85d620343f61aafa004 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Fri, 21 Oct 2022 17:01:31 +0100 Subject: [PATCH] target/arm: Implement FEAT_E0PD FEAT_E0PD adds new bits E0PD0 and E0PD1 to TCR_EL1, which allow the OS to forbid EL0 access to half of the address space. Since this is an EL0-specific variation on the existing TCR_ELx.{EPD0,EPD1}, we can implement it entirely in aa64_va_parameters(). This requires moving the existing regime_is_user() to internals.h so that the code in helper.c can get at it. Reviewed-by: Richard Henderson Signed-off-by: Peter Maydell Message-id: 20221021160131.3531787-1-peter.maydell@linaro.org --- docs/system/arm/emulation.rst | 1 + target/arm/cpu.h | 5 +++++ target/arm/cpu64.c | 1 + target/arm/helper.c | 9 +++++++++ target/arm/internals.h | 19 +++++++++++++++++++ target/arm/ptw.c | 19 ------------------- 6 files changed, 35 insertions(+), 19 deletions(-) diff --git a/docs/system/arm/emulation.rst b/docs/system/arm/emulation.rst index cfb4b0768b..fd61360a08 100644 --- a/docs/system/arm/emulation.rst +++ b/docs/system/arm/emulation.rst @@ -24,6 +24,7 @@ the following architecture extensions: - FEAT_Debugv8p4 (Debug changes for v8.4) - FEAT_DotProd (Advanced SIMD dot product instructions) - FEAT_DoubleFault (Double Fault Extension) +- FEAT_E0PD (Preventing EL0 access to halves of address maps) - FEAT_ETS (Enhanced Translation Synchronization) - FEAT_FCMA (Floating-point complex number instructions) - FEAT_FHM (Floating-point half-precision multiplication instructions) diff --git a/target/arm/cpu.h b/target/arm/cpu.h index db9ec6a038..09564d0393 100644 --- a/target/arm/cpu.h +++ b/target/arm/cpu.h @@ -4147,6 +4147,11 @@ static inline bool isar_feature_aa64_lva(const ARMISARegisters *id) return FIELD_EX64(id->id_aa64mmfr2, ID_AA64MMFR2, VARANGE) != 0; } +static inline bool isar_feature_aa64_e0pd(const ARMISARegisters *id) +{ + return FIELD_EX64(id->id_aa64mmfr2, ID_AA64MMFR2, E0PD) != 0; +} + static inline bool isar_feature_aa64_tts2uxn(const ARMISARegisters *id) { return FIELD_EX64(id->id_aa64mmfr1, ID_AA64MMFR1, XNX) != 0; diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c index 85e0d1daf1..da95eabab5 100644 --- a/target/arm/cpu64.c +++ b/target/arm/cpu64.c @@ -1185,6 +1185,7 @@ static void aarch64_max_initfn(Object *obj) t = FIELD_DP64(t, ID_AA64MMFR2, FWB, 1); /* FEAT_S2FWB */ t = FIELD_DP64(t, ID_AA64MMFR2, TTL, 1); /* FEAT_TTL */ t = FIELD_DP64(t, ID_AA64MMFR2, BBM, 2); /* FEAT_BBM at level 2 */ + t = FIELD_DP64(t, ID_AA64MMFR2, E0PD, 1); /* FEAT_E0PD */ cpu->isar.id_aa64mmfr2 = t; t = cpu->isar.id_aa64zfr0; diff --git a/target/arm/helper.c b/target/arm/helper.c index c672903f43..252651a8d1 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -10491,6 +10491,8 @@ ARMVAParameters aa64_va_parameters(CPUARMState *env, uint64_t va, ps = extract32(tcr, 16, 3); ds = extract64(tcr, 32, 1); } else { + bool e0pd; + /* * Bit 55 is always between the two regions, and is canonical for * determining if address tagging is enabled. @@ -10502,15 +10504,22 @@ ARMVAParameters aa64_va_parameters(CPUARMState *env, uint64_t va, epd = extract32(tcr, 7, 1); sh = extract32(tcr, 12, 2); hpd = extract64(tcr, 41, 1); + e0pd = extract64(tcr, 55, 1); } else { tsz = extract32(tcr, 16, 6); gran = tg1_to_gran_size(extract32(tcr, 30, 2)); epd = extract32(tcr, 23, 1); sh = extract32(tcr, 28, 2); hpd = extract64(tcr, 42, 1); + e0pd = extract64(tcr, 56, 1); } ps = extract64(tcr, 32, 3); ds = extract64(tcr, 59, 1); + + if (e0pd && cpu_isar_feature(aa64_e0pd, cpu) && + regime_is_user(env, mmu_idx)) { + epd = true; + } } gran = sanitize_gran_size(cpu, gran, stage2); diff --git a/target/arm/internals.h b/target/arm/internals.h index b26c9ca17b..1926f3679c 100644 --- a/target/arm/internals.h +++ b/target/arm/internals.h @@ -707,6 +707,25 @@ static inline uint32_t regime_el(CPUARMState *env, ARMMMUIdx mmu_idx) } } +static inline bool regime_is_user(CPUARMState *env, ARMMMUIdx mmu_idx) +{ + switch (mmu_idx) { + case ARMMMUIdx_E20_0: + case ARMMMUIdx_Stage1_E0: + case ARMMMUIdx_MUser: + case ARMMMUIdx_MSUser: + case ARMMMUIdx_MUserNegPri: + case ARMMMUIdx_MSUserNegPri: + return true; + default: + return false; + case ARMMMUIdx_E10_0: + case ARMMMUIdx_E10_1: + case ARMMMUIdx_E10_1_PAN: + g_assert_not_reached(); + } +} + /* Return the SCTLR value which controls this address translation regime */ static inline uint64_t regime_sctlr(CPUARMState *env, ARMMMUIdx mmu_idx) { diff --git a/target/arm/ptw.c b/target/arm/ptw.c index 6c5ed56a10..aed6f92d6f 100644 --- a/target/arm/ptw.c +++ b/target/arm/ptw.c @@ -104,25 +104,6 @@ static bool regime_translation_big_endian(CPUARMState *env, ARMMMUIdx mmu_idx) return (regime_sctlr(env, mmu_idx) & SCTLR_EE) != 0; } -static bool regime_is_user(CPUARMState *env, ARMMMUIdx mmu_idx) -{ - switch (mmu_idx) { - case ARMMMUIdx_E20_0: - case ARMMMUIdx_Stage1_E0: - case ARMMMUIdx_MUser: - case ARMMMUIdx_MSUser: - case ARMMMUIdx_MUserNegPri: - case ARMMMUIdx_MSUserNegPri: - return true; - default: - return false; - case ARMMMUIdx_E10_0: - case ARMMMUIdx_E10_1: - case ARMMMUIdx_E10_1_PAN: - g_assert_not_reached(); - } -} - /* Return the TTBR associated with this translation regime */ static uint64_t regime_ttbr(CPUARMState *env, ARMMMUIdx mmu_idx, int ttbrn) {