From 056f43df9168413f304500b69c33158d66efb7cf Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Fri, 27 Jan 2017 15:20:24 +0000 Subject: [PATCH] armv7m: R14 should reset to 0xffffffff MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit For M profile (unlike A profile) the reset value of R14 is specified as 0xffffffff. (The rationale is that this is an illegal exception return value, so if guest code tries to return to it it will result in a helpful exception.) Registers r0 to r12 and the flags are architecturally UNKNOWN on reset, so we leave those at zero. Signed-off-by: Peter Maydell Reviewed-by: Alex Bennée Message-id: 1485285380-10565-11-git-send-email-peter.maydell@linaro.org --- target/arm/cpu.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/target/arm/cpu.c b/target/arm/cpu.c index 0814f73462..e9f10f7747 100644 --- a/target/arm/cpu.c +++ b/target/arm/cpu.c @@ -196,6 +196,9 @@ static void arm_cpu_reset(CPUState *s) */ env->v7m.ccr = R_V7M_CCR_STKALIGN_MASK; + /* Unlike A/R profile, M profile defines the reset LR value */ + env->regs[14] = 0xffffffff; + /* Load the initial SP and PC from the vector table at address 0 */ rom = rom_ptr(0); if (rom) { -- 2.11.4.GIT