/* * This file is part of the coreboot project. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; version 2 of the License. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #include #include #include #include #include #include #include #include #include #include #if IS_ENABLED(CONFIG_GDB_STUB) /* BUFMAX defines the maximum number of characters in inbound/outbound buffers. * At least NUM_REGBYTES*2 are needed for register packets */ #define BUFMAX 400 enum regnames { EAX = 0, ECX, EDX, EBX, ESP, EBP, ESI, EDI, PC /* also known as eip */, PS /* also known as eflags */, CS, SS, DS, ES, FS, GS, NUM_REGS /* Number of registers. */ }; static uint32_t gdb_stub_registers[NUM_REGS]; #define GDB_SIG0 0 /* Signal 0 */ #define GDB_SIGHUP 1 /* Hangup */ #define GDB_SIGINT 2 /* Interrupt */ #define GDB_SIGQUIT 3 /* Quit */ #define GDB_SIGILL 4 /* Illegal instruction */ #define GDB_SIGTRAP 5 /* Trace/breakpoint trap */ #define GDB_SIGABRT 6 /* Aborted */ #define GDB_SIGEMT 7 /* Emulation trap */ #define GDB_SIGFPE 8 /* Arithmetic exception */ #define GDB_SIGKILL 9 /* Killed */ #define GDB_SIGBUS 10 /* Bus error */ #define GDB_SIGSEGV 11 /* Segmentation fault */ #define GDB_SIGSYS 12 /* Bad system call */ #define GDB_SIGPIPE 13 /* Broken pipe */ #define GDB_SIGALRM 14 /* Alarm clock */ #define GDB_SIGTERM 15 /* Terminated */ #define GDB_SIGURG 16 /* Urgent I/O condition */ #define GDB_SIGSTOP 17 /* Stopped (signal) */ #define GDB_SIGTSTP 18 /* Stopped (user) */ #define GDB_SIGCONT 19 /* Continued */ #define GDB_SIGCHLD 20 /* Child status changed */ #define GDB_SIGTTIN 21 /* Stopped (tty input) */ #define GDB_SIGTTOU 22 /* Stopped (tty output) */ #define GDB_SIGIO 23 /* I/O possible */ #define GDB_SIGXCPU 24 /* CPU time limit exceeded */ #define GDB_SIGXFSZ 25 /* File size limit exceeded */ #define GDB_SIGVTALRM 26 /* Virtual timer expired */ #define GDB_SIGPROF 27 /* Profiling timer expired */ #define GDB_SIGWINCH 28 /* Window size changed */ #define GDB_SIGLOST 29 /* Resource lost */ #define GDB_SIGUSR1 30 /* User defined signal 1 */ #define GDB_SUGUSR2 31 /* User defined signal 2 */ #define GDB_SIGPWR 32 /* Power fail/restart */ #define GDB_SIGPOLL 33 /* Pollable event occurred */ #define GDB_SIGWIND 34 /* SIGWIND */ #define GDB_SIGPHONE 35 /* SIGPHONE */ #define GDB_SIGWAITING 36 /* Process's LWPs are blocked */ #define GDB_SIGLWP 37 /* Signal LWP */ #define GDB_SIGDANGER 38 /* Swap space dangerously low */ #define GDB_SIGGRANT 39 /* Monitor mode granted */ #define GDB_SIGRETRACT 40 /* Need to relinquish monitor mode */ #define GDB_SIGMSG 41 /* Monitor mode data available */ #define GDB_SIGSOUND 42 /* Sound completed */ #define GDB_SIGSAK 43 /* Secure attention */ #define GDB_SIGPRIO 44 /* SIGPRIO */ #define GDB_SIG33 45 /* Real-time event 33 */ #define GDB_SIG34 46 /* Real-time event 34 */ #define GDB_SIG35 47 /* Real-time event 35 */ #define GDB_SIG36 48 /* Real-time event 36 */ #define GDB_SIG37 49 /* Real-time event 37 */ #define GDB_SIG38 50 /* Real-time event 38 */ #define GDB_SIG39 51 /* Real-time event 39 */ #define GDB_SIG40 52 /* Real-time event 40 */ #define GDB_SIG41 53 /* Real-time event 41 */ #define GDB_SIG42 54 /* Real-time event 42 */ #define GDB_SIG43 55 /* Real-time event 43 */ #define GDB_SIG44 56 /* Real-time event 44 */ #define GDB_SIG45 57 /* Real-time event 45 */ #define GDB_SIG46 58 /* Real-time event 46 */ #define GDB_SIG47 59 /* Real-time event 47 */ #define GDB_SIG48 60 /* Real-time event 48 */ #define GDB_SIG49 61 /* Real-time event 49 */ #define GDB_SIG50 62 /* Real-time event 50 */ #define GDB_SIG51 63 /* Real-time event 51 */ #define GDB_SIG52 64 /* Real-time event 52 */ #define GDB_SIG53 65 /* Real-time event 53 */ #define GDB_SIG54 66 /* Real-time event 54 */ #define GDB_SIG55 67 /* Real-time event 55 */ #define GDB_SIG56 68 /* Real-time event 56 */ #define GDB_SIG57 69 /* Real-time event 57 */ #define GDB_SIG58 70 /* Real-time event 58 */ #define GDB_SIG59 71 /* Real-time event 59 */ #define GDB_SIG60 72 /* Real-time event 60 */ #define GDB_SIG61 73 /* Real-time event 61 */ #define GDB_SIG62 74 /* Real-time event 62 */ #define GDB_SIG63 75 /* Real-time event 63 */ #define GDB_SIGCANCEL 76 /* LWP internal signal */ #define GDB_SIG32 77 /* Real-time event 32 */ #define GDB_SIG64 78 /* Real-time event 64 */ #define GDB_SIG65 79 /* Real-time event 65 */ #define GDB_SIG66 80 /* Real-time event 66 */ #define GDB_SIG67 81 /* Real-time event 67 */ #define GDB_SIG68 82 /* Real-time event 68 */ #define GDB_SIG69 83 /* Real-time event 69 */ #define GDB_SIG70 84 /* Real-time event 70 */ #define GDB_SIG71 85 /* Real-time event 71 */ #define GDB_SIG72 86 /* Real-time event 72 */ #define GDB_SIG73 87 /* Real-time event 73 */ #define GDB_SIG74 88 /* Real-time event 74 */ #define GDB_SIG75 89 /* Real-time event 75 */ #define GDB_SIG76 90 /* Real-time event 76 */ #define GDB_SIG77 91 /* Real-time event 77 */ #define GDB_SIG78 92 /* Real-time event 78 */ #define GDB_SIG79 93 /* Real-time event 79 */ #define GDB_SIG80 94 /* Real-time event 80 */ #define GDB_SIG81 95 /* Real-time event 81 */ #define GDB_SIG82 96 /* Real-time event 82 */ #define GDB_SIG83 97 /* Real-time event 83 */ #define GDB_SIG84 98 /* Real-time event 84 */ #define GDB_SIG85 99 /* Real-time event 85 */ #define GDB_SIG86 100 /* Real-time event 86 */ #define GDB_SIG87 101 /* Real-time event 87 */ #define GDB_SIG88 102 /* Real-time event 88 */ #define GDB_SIG89 103 /* Real-time event 89 */ #define GDB_SIG90 104 /* Real-time event 90 */ #define GDB_SIG91 105 /* Real-time event 91 */ #define GDB_SIG92 106 /* Real-time event 92 */ #define GDB_SIG93 107 /* Real-time event 93 */ #define GDB_SIG94 108 /* Real-time event 94 */ #define GDB_SIG95 109 /* Real-time event 95 */ #define GDB_SIG96 110 /* Real-time event 96 */ #define GDB_SIG97 111 /* Real-time event 97 */ #define GDB_SIG98 112 /* Real-time event 98 */ #define GDB_SIG99 113 /* Real-time event 99 */ #define GDB_SIG100 114 /* Real-time event 100 */ #define GDB_SIG101 115 /* Real-time event 101 */ #define GDB_SIG102 116 /* Real-time event 102 */ #define GDB_SIG103 117 /* Real-time event 103 */ #define GDB_SIG104 118 /* Real-time event 104 */ #define GDB_SIG105 119 /* Real-time event 105 */ #define GDB_SIG106 120 /* Real-time event 106 */ #define GDB_SIG107 121 /* Real-time event 107 */ #define GDB_SIG108 122 /* Real-time event 108 */ #define GDB_SIG109 123 /* Real-time event 109 */ #define GDB_SIG110 124 /* Real-time event 110 */ #define GDB_SIG111 125 /* Real-time event 111 */ #define GDB_SIG112 126 /* Real-time event 112 */ #define GDB_SIG113 127 /* Real-time event 113 */ #define GDB_SIG114 128 /* Real-time event 114 */ #define GDB_SIG115 129 /* Real-time event 115 */ #define GDB_SIG116 130 /* Real-time event 116 */ #define GDB_SIG117 131 /* Real-time event 117 */ #define GDB_SIG118 132 /* Real-time event 118 */ #define GDB_SIG119 133 /* Real-time event 119 */ #define GDB_SIG120 134 /* Real-time event 120 */ #define GDB_SIG121 135 /* Real-time event 121 */ #define GDB_SIG122 136 /* Real-time event 122 */ #define GDB_SIG123 137 /* Real-time event 123 */ #define GDB_SIG124 138 /* Real-time event 124 */ #define GDB_SIG125 139 /* Real-time event 125 */ #define GDB_SIG126 140 /* Real-time event 126 */ #define GDB_SIG127 141 /* Real-time event 127 */ #define GDB_SIGINFO 142 /* Information request */ #define GDB_UNKNOWN 143 /* Unknown signal */ #define GDB_DEFAULT 144 /* error: default signal */ /* Mach exceptions */ #define GDB_EXC_BAD_ACCESS 145 /* Could not access memory */ #define GDB_EXC_BAD_INSTRCTION 146 /* Illegal instruction/operand */ #define GDB_EXC_ARITHMETIC 147 /* Arithmetic exception */ #define GDB_EXC_EMULATION 148 /* Emulation instruction */ #define GDB_EXC_SOFTWARE 149 /* Software generated exception */ #define GDB_EXC_BREAKPOINT 150 /* Breakpoint */ static unsigned char exception_to_signal[] = { [0] = GDB_SIGFPE, /* divide by zero */ [1] = GDB_SIGTRAP, /* debug exception */ [2] = GDB_SIGSEGV, /* NMI Interrupt */ [3] = GDB_SIGTRAP, /* Breakpoint */ [4] = GDB_SIGSEGV, /* into instruction (overflow) */ [5] = GDB_SIGSEGV, /* bound instruction */ [6] = GDB_SIGILL, /* Invalid opcode */ [7] = GDB_SIGSEGV, /* coprocessor not available */ [8] = GDB_SIGSEGV, /* double fault */ [9] = GDB_SIGFPE, /* coprocessor segment overrun */ [10] = GDB_SIGSEGV, /* Invalid TSS */ [11] = GDB_SIGBUS, /* Segment not present */ [12] = GDB_SIGBUS, /* stack exception */ [13] = GDB_SIGSEGV, /* general protection */ [14] = GDB_SIGSEGV, /* page fault */ [15] = GDB_UNKNOWN, /* reserved */ [16] = GDB_SIGEMT, /* coprocessor error */ [17] = GDB_SIGBUS, /* alignment check */ [18] = GDB_SIGSEGV, /* machine check */ [19] = GDB_SIGFPE, /* simd floating point exception */ [20] = GDB_UNKNOWN, [21] = GDB_UNKNOWN, [22] = GDB_UNKNOWN, [23] = GDB_UNKNOWN, [24] = GDB_UNKNOWN, [25] = GDB_UNKNOWN, [26] = GDB_UNKNOWN, [27] = GDB_UNKNOWN, [28] = GDB_UNKNOWN, [29] = GDB_UNKNOWN, [30] = GDB_UNKNOWN, [31] = GDB_UNKNOWN, [32] = GDB_SIGINT, /* User interrupt */ }; static const char hexchars[] = "0123456789abcdef"; static char in_buffer[BUFMAX]; static char out_buffer[BUFMAX]; static inline void stub_putc(int ch) { gdb_tx_byte(ch); } static inline void stub_flush(void) { gdb_tx_flush(); } static inline int stub_getc(void) { return gdb_rx_byte(); } static int hex(char ch) { if ((ch >= 'a') && (ch <= 'f')) return (ch - 'a' + 10); if ((ch >= '0') && (ch <= '9')) return (ch - '0'); if ((ch >= 'A') && (ch <= 'F')) return (ch - 'A' + 10); return (-1); } /* * While we find hexadecimal digits, build an int. * Fals is returned if nothing is parsed true otherwise. */ static int parse_ulong(char **ptr, unsigned long *value) { int digit; char *start; start = *ptr; *value = 0; while ((digit = hex(**ptr)) >= 0) { *value = ((*value) << 4) | digit; (*ptr)++; } return start != *ptr; } /* convert the memory pointed to by mem into hex, placing result in buf */ /* return a pointer to the last char put in buf (null) */ static void copy_to_hex(char *buf, void *addr, unsigned long count) { unsigned char ch; char *mem = addr; while (count--) { ch = *mem++; *buf++ = hexchars[ch >> 4]; *buf++ = hexchars[ch & 0x0f]; } *buf = 0; } /* convert the hex array pointed to by buf into binary to be placed in mem */ /* return a pointer to the character AFTER the last byte written */ static void copy_from_hex(void *addr, char *buf, unsigned long count) { unsigned char ch; char *mem = addr; while (count--) { ch = hex(*buf++) << 4; ch = ch + hex(*buf++); *mem++ = ch; } } /* scan for the sequence $# */ static int get_packet(char *buffer) { unsigned char checksum; unsigned char xmitcsum; int count; char ch; /* Wishlit implement a timeout in get_packet */ do { /* wait around for the start character, ignore all other * characters */ while ((ch = (stub_getc() & 0x7f)) != '$') ; checksum = 0; xmitcsum = -1; count = 0; /* now, read until a # or end of buffer is found */ while (count < BUFMAX) { ch = stub_getc() & 0x7f; if (ch == '#') break; checksum = checksum + ch; buffer[count] = ch; count = count + 1; } buffer[count] = 0; if (ch == '#') { xmitcsum = hex(stub_getc() & 0x7f) << 4; xmitcsum += hex(stub_getc() & 0x7f); if (checksum != xmitcsum) { stub_putc('-'); /* failed checksum */ stub_flush(); } else { stub_putc('+'); /* successful transfer */ stub_flush(); } } } while (checksum != xmitcsum); return 1; } /* send the packet in buffer.*/ static void put_packet(char *buffer) { unsigned char checksum; int count; char ch; /* $#. */ do { stub_putc('$'); checksum = 0; count = 0; while ((ch = buffer[count])) { stub_putc(ch); checksum += ch; count += 1; } stub_putc('#'); stub_putc(hexchars[checksum >> 4]); stub_putc(hexchars[checksum % 16]); stub_flush(); } while ((stub_getc() & 0x7f) != '+'); } #endif /* CONFIG_GDB_STUB */ #include void x86_exception(struct eregs *info); void x86_exception(struct eregs *info) { #if IS_ENABLED(CONFIG_GDB_STUB) int signo; memcpy(gdb_stub_registers, info, 8*sizeof(uint32_t)); gdb_stub_registers[PC] = info->eip; gdb_stub_registers[CS] = info->cs; gdb_stub_registers[PS] = info->eflags; signo = GDB_UNKNOWN; if (info->vector < ARRAY_SIZE(exception_to_signal)) signo = exception_to_signal[info->vector]; /* reply to the host that an exception has occurred */ out_buffer[0] = 'S'; out_buffer[1] = hexchars[(signo>>4) & 0xf]; out_buffer[2] = hexchars[signo & 0xf]; out_buffer[3] = '\0'; put_packet(out_buffer); while (1) { unsigned long addr, length; char *ptr; out_buffer[0] = '\0'; out_buffer[1] = '\0'; if (!get_packet(in_buffer)) break; switch (in_buffer[0]) { case '?': /* last signal */ out_buffer[0] = 'S'; out_buffer[1] = hexchars[(signo >> 4) & 0xf]; out_buffer[2] = hexchars[signo & 0xf]; out_buffer[3] = '\0'; break; case 'g': /* return the value of the CPU registers */ copy_to_hex(out_buffer, &gdb_stub_registers, sizeof(gdb_stub_registers)); break; case 'G': /* set the value of the CPU registers - return OK */ copy_from_hex(&gdb_stub_registers, in_buffer + 1, sizeof(gdb_stub_registers)); memcpy(info, gdb_stub_registers, 8*sizeof(uint32_t)); info->eip = gdb_stub_registers[PC]; info->cs = gdb_stub_registers[CS]; info->eflags = gdb_stub_registers[PS]; memcpy(out_buffer, "OK", 3); break; case 'm': /* mAA..AA,LLLL Read LLLL bytes at address AA..AA */ ptr = &in_buffer[1]; if (parse_ulong(&ptr, &addr) && (*ptr++ == ',') && parse_ulong(&ptr, &length)) { copy_to_hex(out_buffer, (void *)addr, length); } else memcpy(out_buffer, "E01", 4); break; case 'M': /* MAA..AA,LLLL: Write LLLL bytes at address AA.AA * return OK */ ptr = &in_buffer[1]; if (parse_ulong(&ptr, &addr) && (*(ptr++) == ',') && parse_ulong(&ptr, &length) && (*(ptr++) == ':')) { copy_from_hex((void *)addr, ptr, length); memcpy(out_buffer, "OK", 3); } else memcpy(out_buffer, "E02", 4); break; case 's': case 'c': /* cAA..AA Continue at address AA..AA(optional) * sAA..AA Step one instruction from AA..AA(optional) */ ptr = &in_buffer[1]; if (parse_ulong(&ptr, &addr)) info->eip = addr; /* Clear the trace bit */ info->eflags &= ~(1 << 8); /* Set the trace bit if we are single stepping */ if (in_buffer[0] == 's') info->eflags |= (1 << 8); return; case 'D': memcpy(out_buffer, "OK", 3); break; case 'k': /* kill request? */ break; case 'q': /* query */ break; case 'z': /* z0AAAA,LLLL remove memory breakpoint */ /* z1AAAA,LLLL remove hardware breakpoint */ /* z2AAAA,LLLL remove write watchpoint */ /* z3AAAA,LLLL remove read watchpoint */ /* z4AAAA,LLLL remove access watchpoint */ case 'Z': /* Z0AAAA,LLLL insert memory breakpoint */ /* Z1AAAA,LLLL insert hardware breakpoint */ /* Z2AAAA,LLLL insert write watchpoint */ /* Z3AAAA,LLLL insert read watchpoint */ /* Z4AAAA,LLLL insert access watchpoint */ break; default: break; } put_packet(out_buffer); } #else /* !CONFIG_GDB_STUB */ #define MDUMP_SIZE 0x80 printk(BIOS_EMERG, "Unexpected Exception: %d @ %02x:%08x - Halting\n" "Code: %d eflags: %08x cr2: %08x\n" "eax: %08x ebx: %08x ecx: %08x edx: %08x\n" "edi: %08x esi: %08x ebp: %08x esp: %08x\n", info->vector, info->cs, info->eip, info->error_code, info->eflags, read_cr2(), info->eax, info->ebx, info->ecx, info->edx, info->edi, info->esi, info->ebp, info->esp); u8 *code = (u8 *)((uintptr_t)info->eip - (MDUMP_SIZE >> 1)); /* Align to 8-byte boundary please, and print eight bytes per row. * This is done to make DRAM burst timing/reordering errors more * evident from the looking at the dump */ code = (u8 *)((uintptr_t)code & ~0x7); int i; for (i = 0; i < MDUMP_SIZE; i++) { if ((i & 0x07) == 0) printk(BIOS_EMERG, "\n%p:\t", code + i); printk(BIOS_EMERG, "%.2x ", code[i]); } die(""); #endif } #define GATE_P (1 << 15) #define GATE_DPL(x) (((x) & 0x3) << 13) #define GATE_SIZE_16 (0 << 11) #define GATE_SIZE_32 (1 << 11) #define IGATE_FLAGS (GATE_P | GATE_DPL(0) | GATE_SIZE_32 | (0x6 << 8)) struct intr_gate { uint16_t offset_0; uint16_t segsel; uint16_t flags; uint16_t offset_1; #if ENV_X86_64 uint32_t offset_2; uint32_t reserved; #endif } __packed; /* Even though the vecX symbols are interrupt entry points just treat them like data to more easily get the pointer values in C. Because IDT entries format splits the offset field up one can't use the linker to resolve parts of a relecation on x86 ABI an array of pointers is used to gather the symbols. The IDT is initialized at runtime when exception_init() is called. */ extern u8 vec0[], vec1[], vec2[], vec3[], vec4[], vec5[], vec6[], vec7[]; extern u8 vec8[], vec9[], vec10[], vec11[], vec12[], vec13[], vec14[], vec15[]; extern u8 vec16[], vec17[], vec18[], vec19[]; static const uintptr_t intr_entries[] = { (uintptr_t)vec0, (uintptr_t)vec1, (uintptr_t)vec2, (uintptr_t)vec3, (uintptr_t)vec4, (uintptr_t)vec5, (uintptr_t)vec6, (uintptr_t)vec7, (uintptr_t)vec8, (uintptr_t)vec9, (uintptr_t)vec10, (uintptr_t)vec11, (uintptr_t)vec12, (uintptr_t)vec13, (uintptr_t)vec14, (uintptr_t)vec15, (uintptr_t)vec16, (uintptr_t)vec17, (uintptr_t)vec18, (uintptr_t)vec19, }; static struct intr_gate idt[ARRAY_SIZE(intr_entries)] __aligned(8) CAR_GLOBAL; static inline uint16_t get_cs(void) { uint16_t segment; asm volatile ( "mov %%cs, %0\n" : "=r" (segment) : : "memory" ); return segment; } struct lidtarg { uint16_t limit; #if ENV_X86_32 uint32_t base; #else uint64_t base; #endif } __packed; /* This global is for src/cpu/x86/lapic/secondary.S usage which is only used during ramstage. */ struct lidtarg idtarg; static void load_idt(void *table, size_t sz) { struct lidtarg lidtarg = { .limit = sz - 1, .base = (uintptr_t)table, }; asm volatile ( "lidt %0" : : "m" (lidtarg) : "memory" ); if (ENV_RAMSTAGE) memcpy(&idtarg, &lidtarg, sizeof(idtarg)); } asmlinkage void exception_init(void) { int i; uint16_t segment; struct intr_gate *gates = car_get_var_ptr(idt); segment = get_cs(); gates = car_get_var_ptr(idt); /* Initialize IDT. */ for (i = 0; i < ARRAY_SIZE(idt); i++) { gates[i].offset_0 = intr_entries[i]; gates[i].segsel = segment; gates[i].flags = IGATE_FLAGS; gates[i].offset_1 = intr_entries[i] >> 16; #if ENV_X86_64 gates[i].offset_2 = intr_entries[i] >> 32; #endif } load_idt(gates, sizeof(idt)); }