From d33abe82c7c9847284a23e575e1078cccab540b5 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Mon, 29 Apr 2019 17:35:58 +0100 Subject: [PATCH] target/arm: Implement dummy versions of M-profile FP-related registers The M-profile floating point support has three associated config registers: FPCAR, FPCCR and FPDSCR. It also makes the registers CPACR and NSACR have behaviour other than reads-as-zero. Add support for all of these as simple reads-as-written registers. We will hook up actual functionality later. The main complexity here is handling the FPCCR register, which has a mix of banked and unbanked bits. Note that we don't share storage with the A-profile cpu->cp15.nsacr and cpu->cp15.cpacr_el1, though the behaviour is quite similar, for two reasons: * the M profile CPACR is banked between security states * it preserves the invariant that M profile uses no state inside the cp15 substruct Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20190416125744.27770-4-peter.maydell@linaro.org --- hw/intc/armv7m_nvic.c | 125 ++++++++++++++++++++++++++++++++++++++++++++++++++ target/arm/cpu.c | 5 ++ target/arm/cpu.h | 34 ++++++++++++++ target/arm/machine.c | 16 +++++++ 4 files changed, 180 insertions(+) diff --git a/hw/intc/armv7m_nvic.c b/hw/intc/armv7m_nvic.c index 45d72f86bd..5eb438f540 100644 --- a/hw/intc/armv7m_nvic.c +++ b/hw/intc/armv7m_nvic.c @@ -1077,6 +1077,16 @@ static uint32_t nvic_readl(NVICState *s, uint32_t offset, MemTxAttrs attrs) } case 0xd84: /* CSSELR */ return cpu->env.v7m.csselr[attrs.secure]; + case 0xd88: /* CPACR */ + if (!arm_feature(&cpu->env, ARM_FEATURE_VFP)) { + return 0; + } + return cpu->env.v7m.cpacr[attrs.secure]; + case 0xd8c: /* NSACR */ + if (!attrs.secure || !arm_feature(&cpu->env, ARM_FEATURE_VFP)) { + return 0; + } + return cpu->env.v7m.nsacr; /* TODO: Implement debug registers. */ case 0xd90: /* MPU_TYPE */ /* Unified MPU; if the MPU is not present this value is zero */ @@ -1222,6 +1232,43 @@ static uint32_t nvic_readl(NVICState *s, uint32_t offset, MemTxAttrs attrs) return 0; } return cpu->env.v7m.sfar; + case 0xf34: /* FPCCR */ + if (!arm_feature(&cpu->env, ARM_FEATURE_VFP)) { + return 0; + } + if (attrs.secure) { + return cpu->env.v7m.fpccr[M_REG_S]; + } else { + /* + * NS can read LSPEN, CLRONRET and MONRDY. It can read + * BFRDY and HFRDY if AIRCR.BFHFNMINS != 0; + * other non-banked bits RAZ. + * TODO: MONRDY should RAZ/WI if DEMCR.SDME is set. + */ + uint32_t value = cpu->env.v7m.fpccr[M_REG_S]; + uint32_t mask = R_V7M_FPCCR_LSPEN_MASK | + R_V7M_FPCCR_CLRONRET_MASK | + R_V7M_FPCCR_MONRDY_MASK; + + if (s->cpu->env.v7m.aircr & R_V7M_AIRCR_BFHFNMINS_MASK) { + mask |= R_V7M_FPCCR_BFRDY_MASK | R_V7M_FPCCR_HFRDY_MASK; + } + + value &= mask; + + value |= cpu->env.v7m.fpccr[M_REG_NS]; + return value; + } + case 0xf38: /* FPCAR */ + if (!arm_feature(&cpu->env, ARM_FEATURE_VFP)) { + return 0; + } + return cpu->env.v7m.fpcar[attrs.secure]; + case 0xf3c: /* FPDSCR */ + if (!arm_feature(&cpu->env, ARM_FEATURE_VFP)) { + return 0; + } + return cpu->env.v7m.fpdscr[attrs.secure]; case 0xf40: /* MVFR0 */ return cpu->isar.mvfr0; case 0xf44: /* MVFR1 */ @@ -1475,6 +1522,18 @@ static void nvic_writel(NVICState *s, uint32_t offset, uint32_t value, cpu->env.v7m.csselr[attrs.secure] = value & R_V7M_CSSELR_INDEX_MASK; } break; + case 0xd88: /* CPACR */ + if (arm_feature(&cpu->env, ARM_FEATURE_VFP)) { + /* We implement only the Floating Point extension's CP10/CP11 */ + cpu->env.v7m.cpacr[attrs.secure] = value & (0xf << 20); + } + break; + case 0xd8c: /* NSACR */ + if (attrs.secure && arm_feature(&cpu->env, ARM_FEATURE_VFP)) { + /* We implement only the Floating Point extension's CP10/CP11 */ + cpu->env.v7m.nsacr = value & (3 << 10); + } + break; case 0xd90: /* MPU_TYPE */ return; /* RO */ case 0xd94: /* MPU_CTRL */ @@ -1703,6 +1762,72 @@ static void nvic_writel(NVICState *s, uint32_t offset, uint32_t value, } break; } + case 0xf34: /* FPCCR */ + if (arm_feature(&cpu->env, ARM_FEATURE_VFP)) { + /* Not all bits here are banked. */ + uint32_t fpccr_s; + + if (!arm_feature(&cpu->env, ARM_FEATURE_V8)) { + /* Don't allow setting of bits not present in v7M */ + value &= (R_V7M_FPCCR_LSPACT_MASK | + R_V7M_FPCCR_USER_MASK | + R_V7M_FPCCR_THREAD_MASK | + R_V7M_FPCCR_HFRDY_MASK | + R_V7M_FPCCR_MMRDY_MASK | + R_V7M_FPCCR_BFRDY_MASK | + R_V7M_FPCCR_MONRDY_MASK | + R_V7M_FPCCR_LSPEN_MASK | + R_V7M_FPCCR_ASPEN_MASK); + } + value &= ~R_V7M_FPCCR_RES0_MASK; + + if (!attrs.secure) { + /* Some non-banked bits are configurably writable by NS */ + fpccr_s = cpu->env.v7m.fpccr[M_REG_S]; + if (!(fpccr_s & R_V7M_FPCCR_LSPENS_MASK)) { + uint32_t lspen = FIELD_EX32(value, V7M_FPCCR, LSPEN); + fpccr_s = FIELD_DP32(fpccr_s, V7M_FPCCR, LSPEN, lspen); + } + if (!(fpccr_s & R_V7M_FPCCR_CLRONRETS_MASK)) { + uint32_t cor = FIELD_EX32(value, V7M_FPCCR, CLRONRET); + fpccr_s = FIELD_DP32(fpccr_s, V7M_FPCCR, CLRONRET, cor); + } + if ((s->cpu->env.v7m.aircr & R_V7M_AIRCR_BFHFNMINS_MASK)) { + uint32_t hfrdy = FIELD_EX32(value, V7M_FPCCR, HFRDY); + uint32_t bfrdy = FIELD_EX32(value, V7M_FPCCR, BFRDY); + fpccr_s = FIELD_DP32(fpccr_s, V7M_FPCCR, HFRDY, hfrdy); + fpccr_s = FIELD_DP32(fpccr_s, V7M_FPCCR, BFRDY, bfrdy); + } + /* TODO MONRDY should RAZ/WI if DEMCR.SDME is set */ + { + uint32_t monrdy = FIELD_EX32(value, V7M_FPCCR, MONRDY); + fpccr_s = FIELD_DP32(fpccr_s, V7M_FPCCR, MONRDY, monrdy); + } + + /* + * All other non-banked bits are RAZ/WI from NS; write + * just the banked bits to fpccr[M_REG_NS]. + */ + value &= R_V7M_FPCCR_BANKED_MASK; + cpu->env.v7m.fpccr[M_REG_NS] = value; + } else { + fpccr_s = value; + } + cpu->env.v7m.fpccr[M_REG_S] = fpccr_s; + } + break; + case 0xf38: /* FPCAR */ + if (arm_feature(&cpu->env, ARM_FEATURE_VFP)) { + value &= ~7; + cpu->env.v7m.fpcar[attrs.secure] = value; + } + break; + case 0xf3c: /* FPDSCR */ + if (arm_feature(&cpu->env, ARM_FEATURE_VFP)) { + value &= 0x07c00000; + cpu->env.v7m.fpdscr[attrs.secure] = value; + } + break; case 0xf50: /* ICIALLU */ case 0xf58: /* ICIMVAU */ case 0xf5c: /* DCIMVAC */ diff --git a/target/arm/cpu.c b/target/arm/cpu.c index bb9fdc6304..be81e197ee 100644 --- a/target/arm/cpu.c +++ b/target/arm/cpu.c @@ -281,6 +281,11 @@ static void arm_cpu_reset(CPUState *s) env->v7m.ccr[M_REG_S] |= R_V7M_CCR_UNALIGN_TRP_MASK; } + if (arm_feature(env, ARM_FEATURE_VFP)) { + env->v7m.fpccr[M_REG_NS] = R_V7M_FPCCR_ASPEN_MASK; + env->v7m.fpccr[M_REG_S] = R_V7M_FPCCR_ASPEN_MASK | + R_V7M_FPCCR_LSPEN_MASK | R_V7M_FPCCR_S_MASK; + } /* Unlike A/R profile, M profile defines the reset LR value */ env->regs[14] = 0xffffffff; diff --git a/target/arm/cpu.h b/target/arm/cpu.h index f7f2f5a99c..67e4e95d44 100644 --- a/target/arm/cpu.h +++ b/target/arm/cpu.h @@ -533,6 +533,11 @@ typedef struct CPUARMState { uint32_t scr[M_REG_NUM_BANKS]; uint32_t msplim[M_REG_NUM_BANKS]; uint32_t psplim[M_REG_NUM_BANKS]; + uint32_t fpcar[M_REG_NUM_BANKS]; + uint32_t fpccr[M_REG_NUM_BANKS]; + uint32_t fpdscr[M_REG_NUM_BANKS]; + uint32_t cpacr[M_REG_NUM_BANKS]; + uint32_t nsacr; } v7m; /* Information associated with an exception about to be taken: @@ -1576,6 +1581,35 @@ FIELD(V7M_CSSELR, LEVEL, 1, 3) */ FIELD(V7M_CSSELR, INDEX, 0, 4) +/* v7M FPCCR bits */ +FIELD(V7M_FPCCR, LSPACT, 0, 1) +FIELD(V7M_FPCCR, USER, 1, 1) +FIELD(V7M_FPCCR, S, 2, 1) +FIELD(V7M_FPCCR, THREAD, 3, 1) +FIELD(V7M_FPCCR, HFRDY, 4, 1) +FIELD(V7M_FPCCR, MMRDY, 5, 1) +FIELD(V7M_FPCCR, BFRDY, 6, 1) +FIELD(V7M_FPCCR, SFRDY, 7, 1) +FIELD(V7M_FPCCR, MONRDY, 8, 1) +FIELD(V7M_FPCCR, SPLIMVIOL, 9, 1) +FIELD(V7M_FPCCR, UFRDY, 10, 1) +FIELD(V7M_FPCCR, RES0, 11, 15) +FIELD(V7M_FPCCR, TS, 26, 1) +FIELD(V7M_FPCCR, CLRONRETS, 27, 1) +FIELD(V7M_FPCCR, CLRONRET, 28, 1) +FIELD(V7M_FPCCR, LSPENS, 29, 1) +FIELD(V7M_FPCCR, LSPEN, 30, 1) +FIELD(V7M_FPCCR, ASPEN, 31, 1) +/* These bits are banked. Others are non-banked and live in the M_REG_S bank */ +#define R_V7M_FPCCR_BANKED_MASK \ + (R_V7M_FPCCR_LSPACT_MASK | \ + R_V7M_FPCCR_USER_MASK | \ + R_V7M_FPCCR_THREAD_MASK | \ + R_V7M_FPCCR_MMRDY_MASK | \ + R_V7M_FPCCR_SPLIMVIOL_MASK | \ + R_V7M_FPCCR_UFRDY_MASK | \ + R_V7M_FPCCR_ASPEN_MASK) + /* * System register ID fields. */ diff --git a/target/arm/machine.c b/target/arm/machine.c index b292549614..09567d4fc6 100644 --- a/target/arm/machine.c +++ b/target/arm/machine.c @@ -305,6 +305,21 @@ static const VMStateDescription vmstate_m_v8m = { } }; +static const VMStateDescription vmstate_m_fp = { + .name = "cpu/m/fp", + .version_id = 1, + .minimum_version_id = 1, + .needed = vfp_needed, + .fields = (VMStateField[]) { + VMSTATE_UINT32_ARRAY(env.v7m.fpcar, ARMCPU, M_REG_NUM_BANKS), + VMSTATE_UINT32_ARRAY(env.v7m.fpccr, ARMCPU, M_REG_NUM_BANKS), + VMSTATE_UINT32_ARRAY(env.v7m.fpdscr, ARMCPU, M_REG_NUM_BANKS), + VMSTATE_UINT32_ARRAY(env.v7m.cpacr, ARMCPU, M_REG_NUM_BANKS), + VMSTATE_UINT32(env.v7m.nsacr, ARMCPU), + VMSTATE_END_OF_LIST() + } +}; + static const VMStateDescription vmstate_m = { .name = "cpu/m", .version_id = 4, @@ -330,6 +345,7 @@ static const VMStateDescription vmstate_m = { &vmstate_m_scr, &vmstate_m_other_sp, &vmstate_m_v8m, + &vmstate_m_fp, NULL } }; -- 2.11.4.GIT