diff options
Diffstat (limited to 'src/rtos/rtos_nuttx_stackings.c')
| -rw-r--r-- | src/rtos/rtos_nuttx_stackings.c | 134 |
1 files changed, 87 insertions, 47 deletions
diff --git a/src/rtos/rtos_nuttx_stackings.c b/src/rtos/rtos_nuttx_stackings.c index b70cccb..6faa56a 100644 --- a/src/rtos/rtos_nuttx_stackings.c +++ b/src/rtos/rtos_nuttx_stackings.c @@ -9,60 +9,100 @@ #include "rtos_nuttx_stackings.h" #include "rtos_standard_stackings.h" #include <target/riscv/riscv.h> +#include <helper/bits.h> -/* see arch/arm/include/armv7-m/irq_cmnvector.h */ +/* The cortex_m target uses nuttx_tcbinfo_stack_read which uses a symbol + * provided by Nuttx to read the registers from memory and place them directly + * in the order we need. This is because the register offsets change with + * different versions of Nuttx, FPU vs non-FPU and ARMv7 vs ARMv8. + * This allows a single function to work with many versions. + */ static const struct stack_register_offset nuttx_stack_offsets_cortex_m[] = { - { ARMV7M_R0, 0x28, 32 }, /* r0 */ - { ARMV7M_R1, 0x2c, 32 }, /* r1 */ - { ARMV7M_R2, 0x30, 32 }, /* r2 */ - { ARMV7M_R3, 0x34, 32 }, /* r3 */ - { ARMV7M_R4, 0x08, 32 }, /* r4 */ - { ARMV7M_R5, 0x0c, 32 }, /* r5 */ - { ARMV7M_R6, 0x10, 32 }, /* r6 */ - { ARMV7M_R7, 0x14, 32 }, /* r7 */ - { ARMV7M_R8, 0x18, 32 }, /* r8 */ - { ARMV7M_R9, 0x1c, 32 }, /* r9 */ - { ARMV7M_R10, 0x20, 32 }, /* r10 */ - { ARMV7M_R11, 0x24, 32 }, /* r11 */ - { ARMV7M_R12, 0x38, 32 }, /* r12 */ - { ARMV7M_R13, 0, 32 }, /* sp */ - { ARMV7M_R14, 0x3c, 32 }, /* lr */ - { ARMV7M_PC, 0x40, 32 }, /* pc */ - { ARMV7M_XPSR, 0x44, 32 }, /* xPSR */ + { ARMV7M_R0, 0, 32 }, /* r0 */ + { ARMV7M_R1, 4, 32 }, /* r1 */ + { ARMV7M_R2, 8, 32 }, /* r2 */ + { ARMV7M_R3, 12, 32 }, /* r3 */ + { ARMV7M_R4, 16, 32 }, /* r4 */ + { ARMV7M_R5, 20, 32 }, /* r5 */ + { ARMV7M_R6, 24, 32 }, /* r6 */ + { ARMV7M_R7, 28, 32 }, /* r7 */ + { ARMV7M_R8, 32, 32 }, /* r8 */ + { ARMV7M_R9, 36, 32 }, /* r9 */ + { ARMV7M_R10, 40, 32 }, /* r10 */ + { ARMV7M_R11, 44, 32 }, /* r11 */ + { ARMV7M_R12, 48, 32 }, /* r12 */ + { ARMV7M_R13, 52, 32 }, /* sp */ + { ARMV7M_R14, 56, 32 }, /* lr */ + { ARMV7M_PC, 60, 32 }, /* pc */ + { ARMV7M_XPSR, 64, 32 }, /* xPSR */ }; -const struct rtos_register_stacking nuttx_stacking_cortex_m = { - .stack_registers_size = 0x48, - .stack_growth_direction = -1, - .num_output_registers = 17, - .register_offsets = nuttx_stack_offsets_cortex_m, -}; +/* The Nuttx stack frame for most architectures has some registers placed + * by hardware and some by software. The hardware register order and number does not change + * but the software registers may change with different versions of Nuttx. + * For example with ARMv7, nuttx-12.3.0 added a new register which changed all + * the offsets. We can either create separate offset tables for each version of Nuttx + * which will break again in the future, or read the offsets from the TCB info. + * Nuttx provides a symbol (g_reg_offs) which holds all the offsets for each stored register. + * This offset table is stored in GDB org.gnu.gdb.xxx feature order. + * The same order we need. + * Please refer: + * https://sourceware.org/gdb/current/onlinedocs/gdb/ARM-Features.html + * https://sourceware.org/gdb/current/onlinedocs/gdb/RISC_002dV-Features.html + */ +static int nuttx_cortex_m_tcbinfo_stack_read(struct target *target, + int64_t stack_ptr, const struct rtos_register_stacking *stacking, + uint8_t *stack_data) +{ + struct rtos *rtos = target->rtos; + target_addr_t xcpreg_off = rtos->symbols[NX_SYM_REG_OFFSETS].address; -static const struct stack_register_offset nuttx_stack_offsets_cortex_m_fpu[] = { - { ARMV7M_R0, 0x6c, 32 }, /* r0 */ - { ARMV7M_R1, 0x70, 32 }, /* r1 */ - { ARMV7M_R2, 0x74, 32 }, /* r2 */ - { ARMV7M_R3, 0x78, 32 }, /* r3 */ - { ARMV7M_R4, 0x08, 32 }, /* r4 */ - { ARMV7M_R5, 0x0c, 32 }, /* r5 */ - { ARMV7M_R6, 0x10, 32 }, /* r6 */ - { ARMV7M_R7, 0x14, 32 }, /* r7 */ - { ARMV7M_R8, 0x18, 32 }, /* r8 */ - { ARMV7M_R9, 0x1c, 32 }, /* r9 */ - { ARMV7M_R10, 0x20, 32 }, /* r10 */ - { ARMV7M_R11, 0x24, 32 }, /* r11 */ - { ARMV7M_R12, 0x7c, 32 }, /* r12 */ - { ARMV7M_R13, 0, 32 }, /* sp */ - { ARMV7M_R14, 0x80, 32 }, /* lr */ - { ARMV7M_PC, 0x84, 32 }, /* pc */ - { ARMV7M_XPSR, 0x88, 32 }, /* xPSR */ -}; + for (int i = 0; i < stacking->num_output_registers; ++i) { + uint16_t stack_reg_offset; + int ret = target_read_u16(rtos->target, xcpreg_off + 2 * i, &stack_reg_offset); + if (ret != ERROR_OK) { + LOG_ERROR("Failed to read stack_reg_offset: ret = %d", ret); + return ret; + } + if (stack_reg_offset != UINT16_MAX && stacking->register_offsets[i].offset >= 0) { + ret = target_read_buffer(target, + stack_ptr + stack_reg_offset, + stacking->register_offsets[i].width_bits / 8, + &stack_data[stacking->register_offsets[i].offset]); + if (ret != ERROR_OK) { + LOG_ERROR("Failed to read register: ret = %d", ret); + return ret; + } + } + } + + /* Offset match nuttx_stack_offsets_cortex_m */ + const int XPSR_OFFSET = 64; + const int SP_OFFSET = 52; + /* Nuttx stack frames (produced in exception_common) store the SP of the ISR minus + * the hardware stack frame size. This SP may include an additional 4 byte alignment + * depending in xPSR[9]. The Nuttx stack frame stores post alignment since the + * hardware will add/remove automatically on both enter/exit. + * We need to adjust the SP to get the real SP of the stack. + * See Arm Reference manual "Stack alignment on exception entry" + */ + uint32_t xpsr = target_buffer_get_u32(target, &stack_data[XPSR_OFFSET]); + if (xpsr & BIT(9)) { + uint32_t sp = target_buffer_get_u32(target, &stack_data[SP_OFFSET]); + target_buffer_set_u32(target, &stack_data[SP_OFFSET], sp - 4 * stacking->stack_growth_direction); + } -const struct rtos_register_stacking nuttx_stacking_cortex_m_fpu = { - .stack_registers_size = 0x8c, + return ERROR_OK; +} + +const struct rtos_register_stacking nuttx_stacking_cortex_m = { + /* nuttx_tcbinfo_stack_read transforms the stack into just output registers */ + .stack_registers_size = ARRAY_SIZE(nuttx_stack_offsets_cortex_m) * 4, .stack_growth_direction = -1, - .num_output_registers = 17, - .register_offsets = nuttx_stack_offsets_cortex_m_fpu, + .num_output_registers = ARRAY_SIZE(nuttx_stack_offsets_cortex_m), + .read_stack = nuttx_cortex_m_tcbinfo_stack_read, + .calculate_process_stack = NULL, /* Stack alignment done in nuttx_cortex_m_tcbinfo_stack_read */ + .register_offsets = nuttx_stack_offsets_cortex_m, }; static const struct stack_register_offset nuttx_stack_offsets_riscv[] = { |