From 21c2dd77a6aa5173764abe1371b06cc2a7541c4f Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 31 Mar 2021 16:48:22 +0100 Subject: [PATCH] Revert "target/arm: Make number of counters in PMCR follow the CPU" This reverts commit f7fb73b8cdd3f77e26f9fcff8cf24ff1b58d200f. This change turned out to be a bit half-baked, and doesn't work with KVM, which fails with the error: "qemu-system-aarch64: Failed to retrieve host CPU features" because KVM does not allow accessing of the PMCR_EL0 value in the scratch "query CPU ID registers" VM unless we have first set the KVM_ARM_VCPU_PMU_V3 feature on the VM. Revert the change for 6.0. Reported-by: Zenghui Yu Signed-off-by: Peter Maydell Tested-by: Zenghui Yu Message-id: 20210331154822.23332-1-peter.maydell@linaro.org --- target/arm/cpu.h | 1 - target/arm/cpu64.c | 3 --- target/arm/cpu_tcg.c | 5 ----- target/arm/helper.c | 29 ++++++++++++----------------- target/arm/kvm64.c | 2 -- 5 files changed, 12 insertions(+), 28 deletions(-) diff --git a/target/arm/cpu.h b/target/arm/cpu.h index fe68f464b3..193a49ec7f 100644 --- a/target/arm/cpu.h +++ b/target/arm/cpu.h @@ -942,7 +942,6 @@ struct ARMCPU { uint64_t id_aa64mmfr2; uint64_t id_aa64dfr0; uint64_t id_aa64dfr1; - uint64_t reset_pmcr_el0; } isar; uint64_t midr; uint32_t revidr; diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c index 5d9d56a33c..f0a9e968c9 100644 --- a/target/arm/cpu64.c +++ b/target/arm/cpu64.c @@ -141,7 +141,6 @@ static void aarch64_a57_initfn(Object *obj) cpu->gic_num_lrs = 4; cpu->gic_vpribits = 5; cpu->gic_vprebits = 5; - cpu->isar.reset_pmcr_el0 = 0x41013000; define_arm_cp_regs(cpu, cortex_a72_a57_a53_cp_reginfo); } @@ -195,7 +194,6 @@ static void aarch64_a53_initfn(Object *obj) cpu->gic_num_lrs = 4; cpu->gic_vpribits = 5; cpu->gic_vprebits = 5; - cpu->isar.reset_pmcr_el0 = 0x41033000; define_arm_cp_regs(cpu, cortex_a72_a57_a53_cp_reginfo); } @@ -247,7 +245,6 @@ static void aarch64_a72_initfn(Object *obj) cpu->gic_num_lrs = 4; cpu->gic_vpribits = 5; cpu->gic_vprebits = 5; - cpu->isar.reset_pmcr_el0 = 0x41023000; define_arm_cp_regs(cpu, cortex_a72_a57_a53_cp_reginfo); } diff --git a/target/arm/cpu_tcg.c b/target/arm/cpu_tcg.c index 8252fd29f9..046e476f65 100644 --- a/target/arm/cpu_tcg.c +++ b/target/arm/cpu_tcg.c @@ -301,7 +301,6 @@ static void cortex_a8_initfn(Object *obj) cpu->ccsidr[1] = 0x2007e01a; /* 16k L1 icache. */ cpu->ccsidr[2] = 0xf0000000; /* No L2 icache. */ cpu->reset_auxcr = 2; - cpu->isar.reset_pmcr_el0 = 0x41002000; define_arm_cp_regs(cpu, cortexa8_cp_reginfo); } @@ -374,7 +373,6 @@ static void cortex_a9_initfn(Object *obj) cpu->clidr = (1 << 27) | (1 << 24) | 3; cpu->ccsidr[0] = 0xe00fe019; /* 16k L1 dcache. */ cpu->ccsidr[1] = 0x200fe019; /* 16k L1 icache. */ - cpu->isar.reset_pmcr_el0 = 0x41093000; define_arm_cp_regs(cpu, cortexa9_cp_reginfo); } @@ -445,7 +443,6 @@ static void cortex_a7_initfn(Object *obj) cpu->ccsidr[0] = 0x701fe00a; /* 32K L1 dcache */ cpu->ccsidr[1] = 0x201fe00a; /* 32K L1 icache */ cpu->ccsidr[2] = 0x711fe07a; /* 4096K L2 unified cache */ - cpu->isar.reset_pmcr_el0 = 0x41072000; define_arm_cp_regs(cpu, cortexa15_cp_reginfo); /* Same as A15 */ } @@ -488,7 +485,6 @@ static void cortex_a15_initfn(Object *obj) cpu->ccsidr[0] = 0x701fe00a; /* 32K L1 dcache */ cpu->ccsidr[1] = 0x201fe00a; /* 32K L1 icache */ cpu->ccsidr[2] = 0x711fe07a; /* 4096K L2 unified cache */ - cpu->isar.reset_pmcr_el0 = 0x410F3000; define_arm_cp_regs(cpu, cortexa15_cp_reginfo); } @@ -721,7 +717,6 @@ static void cortex_r5_initfn(Object *obj) cpu->isar.id_isar6 = 0x0; cpu->mp_is_up = true; cpu->pmsav7_dregion = 16; - cpu->isar.reset_pmcr_el0 = 0x41151800; define_arm_cp_regs(cpu, cortexr5_cp_reginfo); } diff --git a/target/arm/helper.c b/target/arm/helper.c index 8fb6cc96e4..d9220be7c5 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -38,6 +38,7 @@ #endif #define ARM_CPU_FREQ 1000000000 /* FIXME: 1 GHz, should be configurable */ +#define PMCR_NUM_COUNTERS 4 /* QEMU IMPDEF choice */ #ifndef CONFIG_USER_ONLY @@ -1148,9 +1149,7 @@ static const ARMCPRegInfo v6_cp_reginfo[] = { static inline uint32_t pmu_num_counters(CPUARMState *env) { - ARMCPU *cpu = env_archcpu(env); - - return (cpu->isar.reset_pmcr_el0 & PMCRN_MASK) >> PMCRN_SHIFT; + return (env->cp15.c9_pmcr & PMCRN_MASK) >> PMCRN_SHIFT; } /* Bits allowed to be set/cleared for PMCNTEN* and PMINTEN* */ @@ -5754,6 +5753,13 @@ static const ARMCPRegInfo el2_cp_reginfo[] = { .resetvalue = 0, .writefn = gt_hyp_ctl_write, .raw_writefn = raw_write }, #endif + /* The only field of MDCR_EL2 that has a defined architectural reset value + * is MDCR_EL2.HPMN which should reset to the value of PMCR_EL0.N. + */ + { .name = "MDCR_EL2", .state = ARM_CP_STATE_BOTH, + .opc0 = 3, .opc1 = 4, .crn = 1, .crm = 1, .opc2 = 1, + .access = PL2_RW, .resetvalue = PMCR_NUM_COUNTERS, + .fieldoffset = offsetof(CPUARMState, cp15.mdcr_el2), }, { .name = "HPFAR", .state = ARM_CP_STATE_AA32, .cp = 15, .opc1 = 4, .crn = 6, .crm = 0, .opc2 = 4, .access = PL2_RW, .accessfn = access_el3_aa32ns, @@ -6683,7 +6689,7 @@ static void define_pmu_regs(ARMCPU *cpu) * field as main ID register, and we implement four counters in * addition to the cycle count register. */ - unsigned int i, pmcrn = pmu_num_counters(&cpu->env); + unsigned int i, pmcrn = PMCR_NUM_COUNTERS; ARMCPRegInfo pmcr = { .name = "PMCR", .cp = 15, .crn = 9, .crm = 12, .opc1 = 0, .opc2 = 0, .access = PL0_RW, @@ -6698,10 +6704,10 @@ static void define_pmu_regs(ARMCPU *cpu) .access = PL0_RW, .accessfn = pmreg_access, .type = ARM_CP_IO, .fieldoffset = offsetof(CPUARMState, cp15.c9_pmcr), - .resetvalue = cpu->isar.reset_pmcr_el0, + .resetvalue = (cpu->midr & 0xff000000) | (pmcrn << PMCRN_SHIFT) | + PMCRLC, .writefn = pmcr_write, .raw_writefn = raw_write, }; - define_one_arm_cp_reg(cpu, &pmcr); define_one_arm_cp_reg(cpu, &pmcr64); for (i = 0; i < pmcrn; i++) { @@ -7819,17 +7825,6 @@ void register_cp_regs_for_features(ARMCPU *cpu) .fieldoffset = offsetof(CPUARMState, cp15.vmpidr_el2) }, REGINFO_SENTINEL }; - /* - * The only field of MDCR_EL2 that has a defined architectural reset - * value is MDCR_EL2.HPMN which should reset to the value of PMCR_EL0.N. - */ - ARMCPRegInfo mdcr_el2 = { - .name = "MDCR_EL2", .state = ARM_CP_STATE_BOTH, - .opc0 = 3, .opc1 = 4, .crn = 1, .crm = 1, .opc2 = 1, - .access = PL2_RW, .resetvalue = pmu_num_counters(env), - .fieldoffset = offsetof(CPUARMState, cp15.mdcr_el2), - }; - define_one_arm_cp_reg(cpu, &mdcr_el2); define_arm_cp_regs(cpu, vpidr_regs); define_arm_cp_regs(cpu, el2_cp_reginfo); if (arm_feature(env, ARM_FEATURE_V8)) { diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c index 581335e49d..dff85f6db9 100644 --- a/target/arm/kvm64.c +++ b/target/arm/kvm64.c @@ -566,8 +566,6 @@ bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf) ARM64_SYS_REG(3, 0, 0, 7, 1)); err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64mmfr2, ARM64_SYS_REG(3, 0, 0, 7, 2)); - err |= read_sys_reg64(fdarray[2], &ahcf->isar.reset_pmcr_el0, - ARM64_SYS_REG(3, 3, 9, 12, 0)); /* * Note that if AArch32 support is not present in the host, -- 2.11.4.GIT