From e525c38cb8d742d6d5b9f879ddfa588d3e1fcf71 Mon Sep 17 00:00:00 2001 From: Copilot <198982749+Copilot@users.noreply.github.com> Date: Wed, 12 Nov 2025 04:34:34 +0800 Subject: [libcpu][cortex-a] Refactor FPU stack initialization for maintainability (#10919) * Initial plan * [libcpu][cortex-a] Improve FPU stack initialization implementation Co-authored-by: BernardXiong <1241087+BernardXiong@users.noreply.github.com> * [libcpu][cortex-a] Replace FPU init loop with rt_memset Co-authored-by: BernardXiong <1241087+BernardXiong@users.noreply.github.com> --------- Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com> Co-authored-by: BernardXiong <1241087+BernardXiong@users.noreply.github.com> --- libcpu/arm/cortex-a/stack.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'libcpu/arm/cortex-a/stack.c') diff --git a/libcpu/arm/cortex-a/stack.c b/libcpu/arm/cortex-a/stack.c index 4c955677f8..5bb57ca4dd 100644 --- a/libcpu/arm/cortex-a/stack.c +++ b/libcpu/arm/cortex-a/stack.c @@ -61,7 +61,13 @@ rt_uint8_t *rt_hw_stack_init(void *tentry, void *parameter, *(--stk) = 0; /* user sp*/ #endif #ifdef RT_USING_FPU - *(--stk) = 0; /* not use fpu*/ + /* FPU context initialization matches context_gcc.S restore order: + * Stack layout (high to low): FPEXC -> FPSCR -> D16-D31 -> D0-D15 + */ + stk -= VFP_DATA_NR; + rt_memset(stk, 0, VFP_DATA_NR * sizeof(rt_uint32_t)); /* Initialize D0-D31 (64 words for 32 double regs) */ + *(--stk) = 0; /* FPSCR: Floating-Point Status and Control Register */ + *(--stk) = 0x40000000; /* FPEXC: Enable FPU (bit 30 = EN) */ #endif /* return task's current stack address */ -- cgit v1.3.1