From 4d1e7a4745c050f7ccac49a1c01437526b5130b5 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Thu, 14 Sep 2017 18:43:17 +0100 Subject: [PATCH] target/arm: Add and use defines for EXCRET constants The exception-return magic values get some new bits in v8M, which makes some bit definitions for them worthwhile. We don't use the bit definitions for the switch on the low bits which checks the return type for v7M, because this is defined in the v7M ARM ARM as a set of valid values rather than via per-bit checks. Signed-off-by: Peter Maydell Reviewed-by: Alistair Francis Message-id: 1505137930-13255-7-git-send-email-peter.maydell@linaro.org --- target/arm/helper.c | 14 +++++++++----- target/arm/internals.h | 10 ++++++++++ 2 files changed, 19 insertions(+), 5 deletions(-) diff --git a/target/arm/helper.c b/target/arm/helper.c index fdd5cc6bae..a502e4eb33 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -6242,7 +6242,7 @@ static void do_v7m_exception_exit(ARMCPU *cpu) " previous exception %d\n", type, env->v7m.exception); - if (extract32(type, 5, 23) != extract32(-1, 5, 23)) { + if ((type & R_V7M_EXCRET_RES1_MASK) != R_V7M_EXCRET_RES1_MASK) { qemu_log_mask(LOG_GUEST_ERROR, "M profile: zero high bits in exception " "exit PC value 0x%" PRIx32 " are UNPREDICTABLE\n", type); } @@ -6255,7 +6255,7 @@ static void do_v7m_exception_exit(ARMCPU *cpu) * which security state's faultmask to clear. (v8M ARM ARM R_KBNF.) */ if (arm_feature(env, ARM_FEATURE_M_SECURITY)) { - int es = type & 1; + int es = type & R_V7M_EXCRET_ES_MASK; if (armv7m_nvic_raw_execution_priority(env->nvic) >= 0) { env->v7m.faultmask[es] = 0; } @@ -6491,12 +6491,16 @@ void arm_v7m_cpu_do_interrupt(CPUState *cs) return; /* Never happens. Keep compiler happy. */ } - lr = 0xfffffff1; + lr = R_V7M_EXCRET_RES1_MASK | + R_V7M_EXCRET_S_MASK | + R_V7M_EXCRET_DCRS_MASK | + R_V7M_EXCRET_FTYPE_MASK | + R_V7M_EXCRET_ES_MASK; if (env->v7m.control[env->v7m.secure] & R_V7M_CONTROL_SPSEL_MASK) { - lr |= 4; + lr |= R_V7M_EXCRET_SPSEL_MASK; } if (!arm_v7m_is_handler_mode(env)) { - lr |= 8; + lr |= R_V7M_EXCRET_MODE_MASK; } v7m_push_stack(cpu); diff --git a/target/arm/internals.h b/target/arm/internals.h index a315354cfd..18be3702f2 100644 --- a/target/arm/internals.h +++ b/target/arm/internals.h @@ -61,6 +61,16 @@ FIELD(V7M_CONTROL, NPRIV, 0, 1) FIELD(V7M_CONTROL, SPSEL, 1, 1) FIELD(V7M_CONTROL, FPCA, 2, 1) +/* Bit definitions for v7M exception return payload */ +FIELD(V7M_EXCRET, ES, 0, 1) +FIELD(V7M_EXCRET, RES0, 1, 1) +FIELD(V7M_EXCRET, SPSEL, 2, 1) +FIELD(V7M_EXCRET, MODE, 3, 1) +FIELD(V7M_EXCRET, FTYPE, 4, 1) +FIELD(V7M_EXCRET, DCRS, 5, 1) +FIELD(V7M_EXCRET, S, 6, 1) +FIELD(V7M_EXCRET, RES1, 7, 25) /* including the must-be-1 prefix */ + /* * For AArch64, map a given EL to an index in the banked_spsr array. * Note that this mapping and the AArch32 mapping defined in bank_number() -- 2.11.0