/* * Copyright (c) 2019-2020 Cobham Gaisler AB * * SPDX-License-Identifier: Apache-2.0 */ #include #include LOG_MODULE_DECLARE(os, CONFIG_KERNEL_LOG_LEVEL); /* * EXAMPLE OUTPUT * * --------------------------------------------------------------------- * * tt = 0x02, illegal_instruction * * INS LOCALS OUTS GLOBALS * 0: 00000000 f3900fc0 40007c50 00000000 * 1: 00000000 40004bf0 40008d30 40008c00 * 2: 00000000 40004bf4 40008000 00000003 * 3: 40009158 00000000 40009000 00000002 * 4: 40008fa8 40003c00 40008fa8 00000008 * 5: 40009000 f3400fc0 00000000 00000080 * 6: 4000a1f8 40000050 4000a190 00000000 * 7: 40002308 00000000 40001fb8 000000c1 * * psr: f30000c7 wim: 00000008 tbr: 40000020 y: 00000000 * pc: 4000a1f4 npc: 4000a1f8 * * pc sp * #0 4000a1f4 4000a190 * #1 40002308 4000a1f8 * #2 40003b24 4000a258 * * --------------------------------------------------------------------- * * * INTERPRETATION * * INS, LOCALS, OUTS and GLOBALS represent the %i, %l, %o and %g * registers before the trap was taken. * * wim, y, pc and npc are the values before the trap was taken. * tbr has the tbr.tt field (bits 11..4) filled in by hardware * representing the current trap type. psr is read immediately * after the trap was taken so it will have the new CWP and ET=0. * * The "#i pc sp" rows is the stack backtrace. All register * windows are flushed to the stack prior to printing. First row * is the trapping pc and sp (o6). * * * HOW TO USE * * When investigating a crashed program, the first things to look * at is typically the tt, pc and sp (o6). You can lookup the pc * in the assembly list file or use addr2line. In the listing, the * register values in the table above can be used. The linker map * file will give a hint on which stack is active and if it has * overflowed. * * psr bits 11..8 is the processor interrupt (priority) level. 0 * is lowest priority level (all can be taken), and 0xf is the * highest level where only non-maskable interrupts are taken. * * g0 is always zero. g5, g6 are never accessed by the compiler. * g7 is the TLS pointer if enabled. A SAVE instruction decreases * the current window pointer (psr bits 4..0) which results in %o * registers becoming %i registers and a new set of %l registers * appear. RESTORE does the opposite. */ /* * The SPARC V8 ABI guarantees that the stack pointer register * (o6) points to an area organized as "struct savearea" below at * all times when traps are enabled. This is the register save * area where register window registers can be flushed to the * stack. * * We flushed registers to this space in the fault trap entry * handler. Note that the space is allocated by the ABI (compiler) * for each stack frame. * * When printing the registers, we get the "local" and "in" * registers from the ABI stack save area, while the "out" and * "global" registers are taken from the exception stack frame * generated in the fault trap entry. */ struct savearea { uint32_t local[8]; uint32_t in[8]; }; /* * Exception trap type (tt) values according to The SPARC V8 * manual, Table 7-1. */ static const struct { int tt; const char *desc; } TTDESC[] = { { .tt = 0x02, .desc = "illegal_instruction", }, { .tt = 0x07, .desc = "mem_address_not_aligned", }, { .tt = 0x2B, .desc = "data_store_error", }, { .tt = 0x29, .desc = "data_access_error", }, { .tt = 0x09, .desc = "data_access_exception", }, { .tt = 0x21, .desc = "instruction_access_error", }, { .tt = 0x01, .desc = "instruction_access_exception", }, { .tt = 0x04, .desc = "fp_disabled", }, { .tt = 0x08, .desc = "fp_exception", }, { .tt = 0x2A, .desc = "division_by_zero", }, { .tt = 0x03, .desc = "privileged_instruction", }, { .tt = 0x20, .desc = "r_register_access_error", }, { .tt = 0x0B, .desc = "watchpoint_detected", }, { .tt = 0x2C, .desc = "data_access_MMU_miss", }, { .tt = 0x3C, .desc = "instruction_access_MMU_miss", }, { .tt = 0x05, .desc = "window_overflow", }, { .tt = 0x06, .desc = "window_underflow", }, { .tt = 0x0A, .desc = "tag_overflow", }, }; static void print_trap_type(const z_arch_esf_t *esf) { const int tt = (esf->tbr & TBR_TT) >> TBR_TT_BIT; const char *desc = "unknown"; if (tt & 0x80) { desc = "trap_instruction"; } else if (tt >= 0x11 && tt <= 0x1F) { desc = "interrupt"; } else { for (int i = 0; i < ARRAY_SIZE(TTDESC); i++) { if (TTDESC[i].tt == tt) { desc = TTDESC[i].desc; break; } } } LOG_ERR("tt = 0x%02X, %s", tt, desc); } static void print_integer_registers(const z_arch_esf_t *esf) { const struct savearea *flushed = (struct savearea *) esf->out[6]; LOG_ERR(" INS LOCALS OUTS GLOBALS"); for (int i = 0; i < 8; i++) { LOG_ERR( " %d: %08x %08x %08x %08x", i, flushed ? flushed->in[i] : 0, flushed ? flushed->local[i] : 0, esf->out[i], esf->global[i] ); } } static void print_special_registers(const z_arch_esf_t *esf) { LOG_ERR( "psr: %08x wim: %08x tbr: %08x y: %08x", esf->psr, esf->wim, esf->tbr, esf->y ); LOG_ERR(" pc: %08x npc: %08x", esf->pc, esf->npc); } static void print_backtrace(const z_arch_esf_t *esf) { const int MAX_LOGLINES = 40; const struct savearea *s = (struct savearea *) esf->out[6]; LOG_ERR(" pc sp"); LOG_ERR(" #0 %08x %08x", esf->pc, (unsigned int) s); for (int i = 1; s && i < MAX_LOGLINES; i++) { const uint32_t pc = s->in[7]; const uint32_t sp = s->in[6]; if (sp == 0U && pc == 0U) { break; } LOG_ERR(" #%-2d %08x %08x", i, pc, sp); if (sp == 0U || sp & 7U) { break; } s = (const struct savearea *) sp; } } static void print_all(const z_arch_esf_t *esf) { LOG_ERR(""); print_trap_type(esf); LOG_ERR(""); print_integer_registers(esf); LOG_ERR(""); print_special_registers(esf); LOG_ERR(""); print_backtrace(esf); LOG_ERR(""); } FUNC_NORETURN void z_sparc_fatal_error(unsigned int reason, const z_arch_esf_t *esf) { if (esf != NULL) { if (IS_ENABLED(CONFIG_EXTRA_EXCEPTION_INFO)) { print_all(esf); } else { print_special_registers(esf); } } z_fatal_error(reason, esf); CODE_UNREACHABLE; }