diff options
| -rw-r--r-- | libcpu/arm/cortex-a/cpuport.h | 5 | ||||
| -rw-r--r-- | libcpu/arm/cortex-a/stack.c | 13 |
2 files changed, 17 insertions, 1 deletions
diff --git a/libcpu/arm/cortex-a/cpuport.h b/libcpu/arm/cortex-a/cpuport.h index 5fb067999c..c18ae246b2 100644 --- a/libcpu/arm/cortex-a/cpuport.h +++ b/libcpu/arm/cortex-a/cpuport.h @@ -72,6 +72,11 @@ struct rt_hw_stack #define E_Bit (1<<9) #define J_Bit (1<<24) +/* VFP/NEON register count for FPU context */ +#ifndef VFP_DATA_NR +#define VFP_DATA_NR 64 /* 32 double-precision registers = 64 words */ +#endif + #ifdef RT_USING_SMP typedef union { unsigned long slock; diff --git a/libcpu/arm/cortex-a/stack.c b/libcpu/arm/cortex-a/stack.c index 4c955677f8..0117514c61 100644 --- a/libcpu/arm/cortex-a/stack.c +++ b/libcpu/arm/cortex-a/stack.c @@ -31,6 +31,9 @@ rt_uint8_t *rt_hw_stack_init(void *tentry, void *parameter, rt_uint8_t *stack_addr, void *texit) { rt_uint32_t *stk; +#ifdef RT_USING_FPU + rt_uint32_t i; +#endif stack_addr += sizeof(rt_uint32_t); stack_addr = (rt_uint8_t *)RT_ALIGN_DOWN((rt_uint32_t)stack_addr, 8); @@ -61,7 +64,15 @@ 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 + */ + for (i = 0; i < VFP_DATA_NR; i++) + { + *(--stk) = 0; /* 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 */ |