From 987ab45e108953c1c98126c338c2119c243c372b Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Mon, 4 Sep 2017 15:21:52 +0100 Subject: [PATCH] target/arm: Define and use XPSR bit masks The M profile XPSR is almost the same format as the A profile CPSR, but not quite. Define some XPSR_* macros and use them where we definitely dealing with an XPSR rather than reusing the CPSR ones. Signed-off-by: Peter Maydell Reviewed-by: Edgar E. Iglesias Reviewed-by: Richard Henderson Message-id: 1501692241-23310-9-git-send-email-peter.maydell@linaro.org --- target/arm/cpu.h | 38 ++++++++++++++++++++++++++++---------- target/arm/helper.c | 15 ++++++++------- 2 files changed, 36 insertions(+), 17 deletions(-) diff --git a/target/arm/cpu.h b/target/arm/cpu.h index 2f2aa872f736..0b9f9377f823 100644 --- a/target/arm/cpu.h +++ b/target/arm/cpu.h @@ -882,6 +882,22 @@ void pmccntr_sync(CPUARMState *env); /* Mask of bits which may be set by exception return copying them from SPSR */ #define CPSR_ERET_MASK (~CPSR_RESERVED) +/* Bit definitions for M profile XPSR. Most are the same as CPSR. */ +#define XPSR_EXCP 0x1ffU +#define XPSR_SPREALIGN (1U << 9) /* Only set in exception stack frames */ +#define XPSR_IT_2_7 CPSR_IT_2_7 +#define XPSR_GE CPSR_GE +#define XPSR_SFPA (1U << 20) /* Only set in exception stack frames */ +#define XPSR_T (1U << 24) /* Not the same as CPSR_T ! */ +#define XPSR_IT_0_1 CPSR_IT_0_1 +#define XPSR_Q CPSR_Q +#define XPSR_V CPSR_V +#define XPSR_C CPSR_C +#define XPSR_Z CPSR_Z +#define XPSR_N CPSR_N +#define XPSR_NZCV CPSR_NZCV +#define XPSR_IT CPSR_IT + #define TTBCR_N (7U << 0) /* TTBCR.EAE==0 */ #define TTBCR_T0SZ (7U << 0) /* TTBCR.EAE==1 */ #define TTBCR_PD0 (1U << 4) @@ -986,26 +1002,28 @@ static inline uint32_t xpsr_read(CPUARMState *env) /* Set the xPSR. Note that some bits of mask must be all-set or all-clear. */ static inline void xpsr_write(CPUARMState *env, uint32_t val, uint32_t mask) { - if (mask & CPSR_NZCV) { - env->ZF = (~val) & CPSR_Z; + if (mask & XPSR_NZCV) { + env->ZF = (~val) & XPSR_Z; env->NF = val; env->CF = (val >> 29) & 1; env->VF = (val << 3) & 0x80000000; } - if (mask & CPSR_Q) - env->QF = ((val & CPSR_Q) != 0); - if (mask & (1 << 24)) - env->thumb = ((val & (1 << 24)) != 0); - if (mask & CPSR_IT_0_1) { + if (mask & XPSR_Q) { + env->QF = ((val & XPSR_Q) != 0); + } + if (mask & XPSR_T) { + env->thumb = ((val & XPSR_T) != 0); + } + if (mask & XPSR_IT_0_1) { env->condexec_bits &= ~3; env->condexec_bits |= (val >> 25) & 3; } - if (mask & CPSR_IT_2_7) { + if (mask & XPSR_IT_2_7) { env->condexec_bits &= 3; env->condexec_bits |= (val >> 8) & 0xfc; } - if (mask & 0x1ff) { - env->v7m.exception = val & 0x1ff; + if (mask & XPSR_EXCP) { + env->v7m.exception = val & XPSR_EXCP; } } diff --git a/target/arm/helper.c b/target/arm/helper.c index 2fb0202a2848..439ad86d49b3 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -6114,7 +6114,7 @@ static void v7m_push_stack(ARMCPU *cpu) /* Align stack pointer if the guest wants that */ if ((env->regs[13] & 4) && (env->v7m.ccr & R_V7M_CCR_STKALIGN_MASK)) { env->regs[13] -= 4; - xpsr |= 0x200; + xpsr |= XPSR_SPREALIGN; } /* Switch to the handler mode. */ v7m_push(env, xpsr); @@ -6239,10 +6239,11 @@ static void do_v7m_exception_exit(ARMCPU *cpu) env->regs[15] &= ~1U; } xpsr = v7m_pop(env); - xpsr_write(env, xpsr, 0xfffffdff); + xpsr_write(env, xpsr, ~XPSR_SPREALIGN); /* Undo stack alignment. */ - if (xpsr & 0x200) + if (xpsr & XPSR_SPREALIGN) { env->regs[13] |= 4; + } /* The restored xPSR exception field will be zero if we're * resuming in Thread mode. If that doesn't match what the @@ -8688,10 +8689,10 @@ uint32_t HELPER(v7m_mrs)(CPUARMState *env, uint32_t reg) case 0 ... 7: /* xPSR sub-fields */ mask = 0; if ((reg & 1) && el) { - mask |= 0x000001ff; /* IPSR (unpriv. reads as zero) */ + mask |= XPSR_EXCP; /* IPSR (unpriv. reads as zero) */ } if (!(reg & 4)) { - mask |= 0xf8000000; /* APSR */ + mask |= XPSR_NZCV | XPSR_Q; /* APSR */ } /* EPSR reads as zero */ return xpsr_read(env) & mask; @@ -8749,10 +8750,10 @@ void HELPER(v7m_msr)(CPUARMState *env, uint32_t maskreg, uint32_t val) uint32_t apsrmask = 0; if (mask & 8) { - apsrmask |= 0xf8000000; /* APSR NZCVQ */ + apsrmask |= XPSR_NZCV | XPSR_Q; } if ((mask & 4) && arm_feature(env, ARM_FEATURE_THUMB_DSP)) { - apsrmask |= 0x000f0000; /* APSR GE[3:0] */ + apsrmask |= XPSR_GE; } xpsr_write(env, val, apsrmask); }