From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- arch/ppc/kernel/ppc-stub.c | 867 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 867 insertions(+) create mode 100644 arch/ppc/kernel/ppc-stub.c (limited to 'arch/ppc/kernel/ppc-stub.c') diff --git a/arch/ppc/kernel/ppc-stub.c b/arch/ppc/kernel/ppc-stub.c new file mode 100644 index 0000000..d61889c --- /dev/null +++ b/arch/ppc/kernel/ppc-stub.c @@ -0,0 +1,867 @@ +/* + * ppc-stub.c: KGDB support for the Linux kernel. + * + * adapted from arch/sparc/kernel/sparc-stub.c for the PowerPC + * some stuff borrowed from Paul Mackerras' xmon + * Copyright (C) 1998 Michael AK Tesch (tesch@cs.wisc.edu) + * + * Modifications to run under Linux + * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu) + * + * This file originally came from the gdb sources, and the + * copyright notices have been retained below. + */ + +/**************************************************************************** + + THIS SOFTWARE IS NOT COPYRIGHTED + + HP offers the following for use in the public domain. HP makes no + warranty with regard to the software or its performance and the + user accepts the software "AS IS" with all faults. + + HP DISCLAIMS ANY WARRANTIES, EXPRESS OR IMPLIED, WITH REGARD + TO THIS SOFTWARE INCLUDING BUT NOT LIMITED TO THE WARRANTIES + OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. + +****************************************************************************/ + +/**************************************************************************** + * Header: remcom.c,v 1.34 91/03/09 12:29:49 glenne Exp $ + * + * Module name: remcom.c $ + * Revision: 1.34 $ + * Date: 91/03/09 12:29:49 $ + * Contributor: Lake Stevens Instrument Division$ + * + * Description: low level support for gdb debugger. $ + * + * Considerations: only works on target hardware $ + * + * Written by: Glenn Engel $ + * ModuleState: Experimental $ + * + * NOTES: See Below $ + * + * Modified for SPARC by Stu Grossman, Cygnus Support. + * + * This code has been extensively tested on the Fujitsu SPARClite demo board. + * + * To enable debugger support, two things need to happen. One, a + * call to set_debug_traps() is necessary in order to allow any breakpoints + * or error conditions to be properly intercepted and reported to gdb. + * Two, a breakpoint needs to be generated to begin communication. This + * is most easily accomplished by a call to breakpoint(). Breakpoint() + * simulates a breakpoint by executing a trap #1. + * + ************* + * + * The following gdb commands are supported: + * + * command function Return value + * + * g return the value of the CPU registers hex data or ENN + * G set the value of the CPU registers OK or ENN + * qOffsets Get section offsets. Reply is Text=xxx;Data=yyy;Bss=zzz + * + * mAA..AA,LLLL Read LLLL bytes at address AA..AA hex data or ENN + * MAA..AA,LLLL: Write LLLL bytes at address AA.AA OK or ENN + * + * c Resume at current address SNN ( signal NN) + * cAA..AA Continue at address AA..AA SNN + * + * s Step one instruction SNN + * sAA..AA Step one instruction from AA..AA SNN + * + * k kill + * + * ? What was the last sigval ? SNN (signal NN) + * + * bBB..BB Set baud rate to BB..BB OK or BNN, then sets + * baud rate + * + * All commands and responses are sent with a packet which includes a + * checksum. A packet consists of + * + * $#. + * + * where + * :: + * :: > + * + * When a packet is received, it is first acknowledged with either '+' or '-'. + * '+' indicates a successful transfer. '-' indicates a failed transfer. + * + * Example: + * + * Host: Reply: + * $m0,10#2a +$00010203040506070809101112131415#42 + * + ****************************************************************************/ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include + +void breakinst(void); + +/* + * BUFMAX defines the maximum number of characters in inbound/outbound buffers + * at least NUMREGBYTES*2 are needed for register packets + */ +#define BUFMAX 2048 +static char remcomInBuffer[BUFMAX]; +static char remcomOutBuffer[BUFMAX]; + +static int initialized; +static int kgdb_active; +static int kgdb_started; +static u_int fault_jmp_buf[100]; +static int kdebug; + + +static const char hexchars[]="0123456789abcdef"; + +/* Place where we save old trap entries for restoration - sparc*/ +/* struct tt_entry kgdb_savettable[256]; */ +/* typedef void (*trapfunc_t)(void); */ + +static void kgdb_fault_handler(struct pt_regs *regs); +static int handle_exception (struct pt_regs *regs); + +#if 0 +/* Install an exception handler for kgdb */ +static void exceptionHandler(int tnum, unsigned int *tfunc) +{ + /* We are dorking with a live trap table, all irqs off */ +} +#endif + +int +kgdb_setjmp(long *buf) +{ + asm ("mflr 0; stw 0,0(%0);" + "stw 1,4(%0); stw 2,8(%0);" + "mfcr 0; stw 0,12(%0);" + "stmw 13,16(%0)" + : : "r" (buf)); + /* XXX should save fp regs as well */ + return 0; +} +void +kgdb_longjmp(long *buf, int val) +{ + if (val == 0) + val = 1; + asm ("lmw 13,16(%0);" + "lwz 0,12(%0); mtcrf 0x38,0;" + "lwz 0,0(%0); lwz 1,4(%0); lwz 2,8(%0);" + "mtlr 0; mr 3,%1" + : : "r" (buf), "r" (val)); +} +/* Convert ch from a hex digit to an int */ +static int +hex(unsigned 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; +} + +/* Convert the memory pointed to by mem into hex, placing result in buf. + * Return a pointer to the last char put in buf (null), in case of mem fault, + * return 0. + */ +static unsigned char * +mem2hex(const char *mem, char *buf, int count) +{ + unsigned char ch; + unsigned short tmp_s; + unsigned long tmp_l; + + if (kgdb_setjmp((long*)fault_jmp_buf) == 0) { + debugger_fault_handler = kgdb_fault_handler; + + /* Accessing 16 bit and 32 bit objects in a single + ** load instruction is required to avoid bad side + ** effects for some IO registers. + */ + + if ((count == 2) && (((long)mem & 1) == 0)) { + tmp_s = *(unsigned short *)mem; + mem += 2; + *buf++ = hexchars[(tmp_s >> 12) & 0xf]; + *buf++ = hexchars[(tmp_s >> 8) & 0xf]; + *buf++ = hexchars[(tmp_s >> 4) & 0xf]; + *buf++ = hexchars[tmp_s & 0xf]; + + } else if ((count == 4) && (((long)mem & 3) == 0)) { + tmp_l = *(unsigned int *)mem; + mem += 4; + *buf++ = hexchars[(tmp_l >> 28) & 0xf]; + *buf++ = hexchars[(tmp_l >> 24) & 0xf]; + *buf++ = hexchars[(tmp_l >> 20) & 0xf]; + *buf++ = hexchars[(tmp_l >> 16) & 0xf]; + *buf++ = hexchars[(tmp_l >> 12) & 0xf]; + *buf++ = hexchars[(tmp_l >> 8) & 0xf]; + *buf++ = hexchars[(tmp_l >> 4) & 0xf]; + *buf++ = hexchars[tmp_l & 0xf]; + + } else { + while (count-- > 0) { + ch = *mem++; + *buf++ = hexchars[ch >> 4]; + *buf++ = hexchars[ch & 0xf]; + } + } + + } else { + /* error condition */ + } + debugger_fault_handler = NULL; + *buf = 0; + return buf; +} + +/* 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 char * +hex2mem(char *buf, char *mem, int count) +{ + unsigned char ch; + int i; + char *orig_mem; + unsigned short tmp_s; + unsigned long tmp_l; + + orig_mem = mem; + + if (kgdb_setjmp((long*)fault_jmp_buf) == 0) { + debugger_fault_handler = kgdb_fault_handler; + + /* Accessing 16 bit and 32 bit objects in a single + ** store instruction is required to avoid bad side + ** effects for some IO registers. + */ + + if ((count == 2) && (((long)mem & 1) == 0)) { + tmp_s = hex(*buf++) << 12; + tmp_s |= hex(*buf++) << 8; + tmp_s |= hex(*buf++) << 4; + tmp_s |= hex(*buf++); + + *(unsigned short *)mem = tmp_s; + mem += 2; + + } else if ((count == 4) && (((long)mem & 3) == 0)) { + tmp_l = hex(*buf++) << 28; + tmp_l |= hex(*buf++) << 24; + tmp_l |= hex(*buf++) << 20; + tmp_l |= hex(*buf++) << 16; + tmp_l |= hex(*buf++) << 12; + tmp_l |= hex(*buf++) << 8; + tmp_l |= hex(*buf++) << 4; + tmp_l |= hex(*buf++); + + *(unsigned long *)mem = tmp_l; + mem += 4; + + } else { + for (i=0; i# */ +static void +getpacket(char *buffer) +{ + unsigned char checksum; + unsigned char xmitcsum; + int i; + int count; + unsigned char ch; + + do { + /* wait around for the start character, ignore all other + * characters */ + while ((ch = (getDebugChar() & 0x7f)) != '$') ; + + checksum = 0; + xmitcsum = -1; + + count = 0; + + /* now, read until a # or end of buffer is found */ + while (count < BUFMAX) { + ch = getDebugChar() & 0x7f; + if (ch == '#') + break; + checksum = checksum + ch; + buffer[count] = ch; + count = count + 1; + } + + if (count >= BUFMAX) + continue; + + buffer[count] = 0; + + if (ch == '#') { + xmitcsum = hex(getDebugChar() & 0x7f) << 4; + xmitcsum |= hex(getDebugChar() & 0x7f); + if (checksum != xmitcsum) + putDebugChar('-'); /* failed checksum */ + else { + putDebugChar('+'); /* successful transfer */ + /* if a sequence char is present, reply the ID */ + if (buffer[2] == ':') { + putDebugChar(buffer[0]); + putDebugChar(buffer[1]); + /* remove sequence chars from buffer */ + count = strlen(buffer); + for (i=3; i <= count; i++) + buffer[i-3] = buffer[i]; + } + } + } + } while (checksum != xmitcsum); +} + +/* send the packet in buffer. */ +static void putpacket(unsigned char *buffer) +{ + unsigned char checksum; + int count; + unsigned char ch, recv; + + /* $#. */ + do { + putDebugChar('$'); + checksum = 0; + count = 0; + + while ((ch = buffer[count])) { + putDebugChar(ch); + checksum += ch; + count += 1; + } + + putDebugChar('#'); + putDebugChar(hexchars[checksum >> 4]); + putDebugChar(hexchars[checksum & 0xf]); + recv = getDebugChar(); + } while ((recv & 0x7f) != '+'); +} + +static void kgdb_flush_cache_all(void) +{ + flush_instruction_cache(); +} + +/* Set up exception handlers for tracing and breakpoints + * [could be called kgdb_init()] + */ +void set_debug_traps(void) +{ +#if 0 + unsigned char c; + + save_and_cli(flags); + + /* In case GDB is started before us, ack any packets (presumably + * "$?#xx") sitting there. + * + * I've found this code causes more problems than it solves, + * so that's why it's commented out. GDB seems to work fine + * now starting either before or after the kernel -bwb + */ + + while((c = getDebugChar()) != '$'); + while((c = getDebugChar()) != '#'); + c = getDebugChar(); /* eat first csum byte */ + c = getDebugChar(); /* eat second csum byte */ + putDebugChar('+'); /* ack it */ +#endif + debugger = kgdb; + debugger_bpt = kgdb_bpt; + debugger_sstep = kgdb_sstep; + debugger_iabr_match = kgdb_iabr_match; + debugger_dabr_match = kgdb_dabr_match; + + initialized = 1; +} + +static void kgdb_fault_handler(struct pt_regs *regs) +{ + kgdb_longjmp((long*)fault_jmp_buf, 1); +} + +int kgdb_bpt(struct pt_regs *regs) +{ + return handle_exception(regs); +} + +int kgdb_sstep(struct pt_regs *regs) +{ + return handle_exception(regs); +} + +void kgdb(struct pt_regs *regs) +{ + handle_exception(regs); +} + +int kgdb_iabr_match(struct pt_regs *regs) +{ + printk(KERN_ERR "kgdb doesn't support iabr, what?!?\n"); + return handle_exception(regs); +} + +int kgdb_dabr_match(struct pt_regs *regs) +{ + printk(KERN_ERR "kgdb doesn't support dabr, what?!?\n"); + return handle_exception(regs); +} + +/* Convert the hardware trap type code to a unix signal number. */ +/* + * This table contains the mapping between PowerPC hardware trap types, and + * signals, which are primarily what GDB understands. + */ +static struct hard_trap_info +{ + unsigned int tt; /* Trap type code for powerpc */ + unsigned char signo; /* Signal that we map this trap into */ +} hard_trap_info[] = { +#if defined(CONFIG_40x) || defined(CONFIG_BOOKE) + { 0x100, SIGINT }, /* critical input interrupt */ + { 0x200, SIGSEGV }, /* machine check */ + { 0x300, SIGSEGV }, /* data storage */ + { 0x400, SIGBUS }, /* instruction storage */ + { 0x500, SIGINT }, /* interrupt */ + { 0x600, SIGBUS }, /* alignment */ + { 0x700, SIGILL }, /* program */ + { 0x800, SIGILL }, /* reserved */ + { 0x900, SIGILL }, /* reserved */ + { 0xa00, SIGILL }, /* reserved */ + { 0xb00, SIGILL }, /* reserved */ + { 0xc00, SIGCHLD }, /* syscall */ + { 0xd00, SIGILL }, /* reserved */ + { 0xe00, SIGILL }, /* reserved */ + { 0xf00, SIGILL }, /* reserved */ + /* + ** 0x1000 PIT + ** 0x1010 FIT + ** 0x1020 watchdog + ** 0x1100 data TLB miss + ** 0x1200 instruction TLB miss + */ + { 0x2002, SIGTRAP}, /* debug */ +#else + { 0x200, SIGSEGV }, /* machine check */ + { 0x300, SIGSEGV }, /* address error (store) */ + { 0x400, SIGBUS }, /* instruction bus error */ + { 0x500, SIGINT }, /* interrupt */ + { 0x600, SIGBUS }, /* alingment */ + { 0x700, SIGTRAP }, /* breakpoint trap */ + { 0x800, SIGFPE }, /* fpu unavail */ + { 0x900, SIGALRM }, /* decrementer */ + { 0xa00, SIGILL }, /* reserved */ + { 0xb00, SIGILL }, /* reserved */ + { 0xc00, SIGCHLD }, /* syscall */ + { 0xd00, SIGTRAP }, /* single-step/watch */ + { 0xe00, SIGFPE }, /* fp assist */ +#endif + { 0, 0} /* Must be last */ + +}; + +static int computeSignal(unsigned int tt) +{ + struct hard_trap_info *ht; + + for (ht = hard_trap_info; ht->tt && ht->signo; ht++) + if (ht->tt == tt) + return ht->signo; + + return SIGHUP; /* default for things we don't know about */ +} + +#define PC_REGNUM 64 +#define SP_REGNUM 1 + +/* + * This function does all command processing for interfacing to gdb. + */ +static int +handle_exception (struct pt_regs *regs) +{ + int sigval; + int addr; + int length; + char *ptr; + unsigned int msr; + + /* We don't handle user-mode breakpoints. */ + if (user_mode(regs)) + return 0; + + if (debugger_fault_handler) { + debugger_fault_handler(regs); + panic("kgdb longjump failed!\n"); + } + if (kgdb_active) { + printk(KERN_ERR "interrupt while in kgdb, returning\n"); + return 0; + } + + kgdb_active = 1; + kgdb_started = 1; + +#ifdef KGDB_DEBUG + printk("kgdb: entering handle_exception; trap [0x%x]\n", + (unsigned int)regs->trap); +#endif + + kgdb_interruptible(0); + lock_kernel(); + msr = mfmsr(); + mtmsr(msr & ~MSR_EE); /* disable interrupts */ + + if (regs->nip == (unsigned long)breakinst) { + /* Skip over breakpoint trap insn */ + regs->nip += 4; + } + + /* reply to host that an exception has occurred */ + sigval = computeSignal(regs->trap); + ptr = remcomOutBuffer; + + *ptr++ = 'T'; + *ptr++ = hexchars[sigval >> 4]; + *ptr++ = hexchars[sigval & 0xf]; + *ptr++ = hexchars[PC_REGNUM >> 4]; + *ptr++ = hexchars[PC_REGNUM & 0xf]; + *ptr++ = ':'; + ptr = mem2hex((char *)®s->nip, ptr, 4); + *ptr++ = ';'; + *ptr++ = hexchars[SP_REGNUM >> 4]; + *ptr++ = hexchars[SP_REGNUM & 0xf]; + *ptr++ = ':'; + ptr = mem2hex(((char *)regs) + SP_REGNUM*4, ptr, 4); + *ptr++ = ';'; + *ptr++ = 0; + + putpacket(remcomOutBuffer); + if (kdebug) + printk("remcomOutBuffer: %s\n", remcomOutBuffer); + + /* XXX We may want to add some features dealing with poking the + * XXX page tables, ... (look at sparc-stub.c for more info) + * XXX also required hacking to the gdb sources directly... + */ + + while (1) { + remcomOutBuffer[0] = 0; + + getpacket(remcomInBuffer); + switch (remcomInBuffer[0]) { + case '?': /* report most recent signal */ + remcomOutBuffer[0] = 'S'; + remcomOutBuffer[1] = hexchars[sigval >> 4]; + remcomOutBuffer[2] = hexchars[sigval & 0xf]; + remcomOutBuffer[3] = 0; + break; +#if 0 + case 'q': /* this screws up gdb for some reason...*/ + { + extern long _start, sdata, __bss_start; + + ptr = &remcomInBuffer[1]; + if (strncmp(ptr, "Offsets", 7) != 0) + break; + + ptr = remcomOutBuffer; + sprintf(ptr, "Text=%8.8x;Data=%8.8x;Bss=%8.8x", + &_start, &sdata, &__bss_start); + break; + } +#endif + case 'd': + /* toggle debug flag */ + kdebug ^= 1; + break; + + case 'g': /* return the value of the CPU registers. + * some of them are non-PowerPC names :( + * they are stored in gdb like: + * struct { + * u32 gpr[32]; + * f64 fpr[32]; + * u32 pc, ps, cnd, lr; (ps=msr) + * u32 cnt, xer, mq; + * } + */ + { + int i; + ptr = remcomOutBuffer; + /* General Purpose Regs */ + ptr = mem2hex((char *)regs, ptr, 32 * 4); + /* Floating Point Regs - FIXME */ + /*ptr = mem2hex((char *), ptr, 32 * 8);*/ + for(i=0; i<(32*8*2); i++) { /* 2chars/byte */ + ptr[i] = '0'; + } + ptr += 32*8*2; + /* pc, msr, cr, lr, ctr, xer, (mq is unused) */ + ptr = mem2hex((char *)®s->nip, ptr, 4); + ptr = mem2hex((char *)®s->msr, ptr, 4); + ptr = mem2hex((char *)®s->ccr, ptr, 4); + ptr = mem2hex((char *)®s->link, ptr, 4); + ptr = mem2hex((char *)®s->ctr, ptr, 4); + ptr = mem2hex((char *)®s->xer, ptr, 4); + } + break; + + case 'G': /* set the value of the CPU registers */ + { + ptr = &remcomInBuffer[1]; + + /* + * If the stack pointer has moved, you should pray. + * (cause only god can help you). + */ + + /* General Purpose Regs */ + hex2mem(ptr, (char *)regs, 32 * 4); + + /* Floating Point Regs - FIXME?? */ + /*ptr = hex2mem(ptr, ??, 32 * 8);*/ + ptr += 32*8*2; + + /* pc, msr, cr, lr, ctr, xer, (mq is unused) */ + ptr = hex2mem(ptr, (char *)®s->nip, 4); + ptr = hex2mem(ptr, (char *)®s->msr, 4); + ptr = hex2mem(ptr, (char *)®s->ccr, 4); + ptr = hex2mem(ptr, (char *)®s->link, 4); + ptr = hex2mem(ptr, (char *)®s->ctr, 4); + ptr = hex2mem(ptr, (char *)®s->xer, 4); + + strcpy(remcomOutBuffer,"OK"); + } + break; + case 'H': + /* don't do anything, yet, just acknowledge */ + hexToInt(&ptr, &addr); + strcpy(remcomOutBuffer,"OK"); + break; + + case 'm': /* mAA..AA,LLLL Read LLLL bytes at address AA..AA */ + /* Try to read %x,%x. */ + + ptr = &remcomInBuffer[1]; + + if (hexToInt(&ptr, &addr) && *ptr++ == ',' + && hexToInt(&ptr, &length)) { + if (mem2hex((char *)addr, remcomOutBuffer, + length)) + break; + strcpy(remcomOutBuffer, "E03"); + } else + strcpy(remcomOutBuffer, "E01"); + break; + + case 'M': /* MAA..AA,LLLL: Write LLLL bytes at address AA.AA return OK */ + /* Try to read '%x,%x:'. */ + + ptr = &remcomInBuffer[1]; + + if (hexToInt(&ptr, &addr) && *ptr++ == ',' + && hexToInt(&ptr, &length) + && *ptr++ == ':') { + if (hex2mem(ptr, (char *)addr, length)) + strcpy(remcomOutBuffer, "OK"); + else + strcpy(remcomOutBuffer, "E03"); + flush_icache_range(addr, addr+length); + } else + strcpy(remcomOutBuffer, "E02"); + break; + + + case 'k': /* kill the program, actually just continue */ + case 'c': /* cAA..AA Continue; address AA..AA optional */ + /* try to read optional parameter, pc unchanged if no parm */ + + ptr = &remcomInBuffer[1]; + if (hexToInt(&ptr, &addr)) + regs->nip = addr; + +/* Need to flush the instruction cache here, as we may have deposited a + * breakpoint, and the icache probably has no way of knowing that a data ref to + * some location may have changed something that is in the instruction cache. + */ + kgdb_flush_cache_all(); + mtmsr(msr); + + kgdb_interruptible(1); + unlock_kernel(); + kgdb_active = 0; + if (kdebug) { + printk("remcomInBuffer: %s\n", remcomInBuffer); + printk("remcomOutBuffer: %s\n", remcomOutBuffer); + } + return 1; + + case 's': + kgdb_flush_cache_all(); +#if defined(CONFIG_40x) || defined(CONFIG_BOOKE) + mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) | DBCR0_IC); + regs->msr |= MSR_DE; +#else + regs->msr |= MSR_SE; +#endif + unlock_kernel(); + kgdb_active = 0; + if (kdebug) { + printk("remcomInBuffer: %s\n", remcomInBuffer); + printk("remcomOutBuffer: %s\n", remcomOutBuffer); + } + return 1; + + case 'r': /* Reset (if user process..exit ???)*/ + panic("kgdb reset."); + break; + } /* switch */ + if (remcomOutBuffer[0] && kdebug) { + printk("remcomInBuffer: %s\n", remcomInBuffer); + printk("remcomOutBuffer: %s\n", remcomOutBuffer); + } + /* reply to the request */ + putpacket(remcomOutBuffer); + } /* while(1) */ +} + +/* This function will generate a breakpoint exception. It is used at the + beginning of a program to sync up with a debugger and can be used + otherwise as a quick means to stop program execution and "break" into + the debugger. */ + +void +breakpoint(void) +{ + if (!initialized) { + printk("breakpoint() called b4 kgdb init\n"); + return; + } + + asm(" .globl breakinst \n\ + breakinst: .long 0x7d821008"); +} + +#ifdef CONFIG_KGDB_CONSOLE +/* Output string in GDB O-packet format if GDB has connected. If nothing + output, returns 0 (caller must then handle output). */ +int +kgdb_output_string (const char* s, unsigned int count) +{ + char buffer[512]; + + if (!kgdb_started) + return 0; + + count = (count <= (sizeof(buffer) / 2 - 2)) + ? count : (sizeof(buffer) / 2 - 2); + + buffer[0] = 'O'; + mem2hex (s, &buffer[1], count); + putpacket(buffer); + + return 1; +} +#endif + +static void sysrq_handle_gdb(int key, struct pt_regs *pt_regs, + struct tty_struct *tty) +{ + printk("Entering GDB stub\n"); + breakpoint(); +} +static struct sysrq_key_op sysrq_gdb_op = { + .handler = sysrq_handle_gdb, + .help_msg = "Gdb", + .action_msg = "GDB", +}; + +static int gdb_register_sysrq(void) +{ + printk("Registering GDB sysrq handler\n"); + register_sysrq_key('g', &sysrq_gdb_op); + return 0; +} +module_init(gdb_register_sysrq); -- cgit v1.1