diff options
Diffstat (limited to 'lib_ppc/kgdb.c')
| -rw-r--r-- | lib_ppc/kgdb.c | 326 |
1 files changed, 326 insertions, 0 deletions
diff --git a/lib_ppc/kgdb.c b/lib_ppc/kgdb.c new file mode 100644 index 0000000..cef35d3 --- /dev/null +++ b/lib_ppc/kgdb.c @@ -0,0 +1,326 @@ +#include <common.h> +#include <command.h> + +#if (CONFIG_COMMANDS & CFG_CMD_KGDB) + +#include <kgdb.h> +#include <asm/signal.h> +#include <asm/processor.h> + +#define PC_REGNUM 64 +#define SP_REGNUM 1 + +void breakinst(void); + +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)); +} + +static inline unsigned long +get_msr(void) +{ + unsigned long msr; + asm volatile("mfmsr %0" : "=r" (msr):); + return msr; +} + +static inline void +set_msr(unsigned long msr) +{ + asm volatile("mtmsr %0" : : "r" (msr)); +} + +/* Convert the SPARC 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[] = { + { 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 */ + { 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 */ +} + +void +kgdb_enter(struct pt_regs *regs, kgdb_data *kdp) +{ + unsigned long msr; + + kdp->private[0] = msr = get_msr(); + set_msr(msr & ~MSR_EE); /* disable interrupts */ + + if (regs->nip == (unsigned long)breakinst) { + /* Skip over breakpoint trap insn */ + regs->nip += 4; + } + regs->msr &= ~MSR_SE; + + /* reply to host that an exception has occurred */ + kdp->sigval = computeSignal(regs->trap); + + kdp->nregs = 2; + + kdp->regs[0].num = PC_REGNUM; + kdp->regs[0].val = regs->nip; + + kdp->regs[1].num = SP_REGNUM; + kdp->regs[1].val = regs->gpr[SP_REGNUM]; +} + +void +kgdb_exit(struct pt_regs *regs, kgdb_data *kdp) +{ + unsigned long msr = kdp->private[0]; + + if (kdp->extype & KGDBEXIT_WITHADDR) + regs->nip = kdp->exaddr; + + switch (kdp->extype & KGDBEXIT_TYPEMASK) { + + case KGDBEXIT_KILL: + case KGDBEXIT_CONTINUE: + set_msr(msr); + break; + + case KGDBEXIT_SINGLE: + regs->msr |= MSR_SE; +#if 0 + set_msr(msr | MSR_SE); +#endif + break; + } +} + +int +kgdb_trap(struct pt_regs *regs) +{ + return (regs->trap); +} + +/* 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; + * } + */ + +#define SPACE_REQUIRED ((32*4)+(32*8)+(6*4)) + +#ifdef CONFIG_8260 +/* store floating double indexed */ +#define STFDI(n,p) __asm__ __volatile__ ("stfd " #n ",%0" : "=o"(p[2*n])) +/* store floating double multiple */ +#define STFDM(p) { STFDI( 0,p); STFDI( 1,p); STFDI( 2,p); STFDI( 3,p); \ + STFDI( 4,p); STFDI( 5,p); STFDI( 6,p); STFDI( 7,p); \ + STFDI( 8,p); STFDI( 9,p); STFDI(10,p); STFDI(11,p); \ + STFDI(12,p); STFDI(13,p); STFDI(14,p); STFDI(15,p); \ + STFDI(16,p); STFDI(17,p); STFDI(18,p); STFDI(19,p); \ + STFDI(20,p); STFDI(21,p); STFDI(22,p); STFDI(23,p); \ + STFDI(24,p); STFDI(25,p); STFDI(26,p); STFDI(27,p); \ + STFDI(28,p); STFDI(29,p); STFDI(30,p); STFDI(31,p); } +#endif + +int +kgdb_getregs(struct pt_regs *regs, char *buf, int max) +{ + int i; + unsigned long *ptr = (unsigned long *)buf; + + if (max < SPACE_REQUIRED) + kgdb_error(KGDBERR_NOSPACE); + + if ((unsigned long)ptr & 3) + kgdb_error(KGDBERR_ALIGNFAULT); + + /* General Purpose Regs */ + for (i = 0; i < 32; i++) + *ptr++ = regs->gpr[i]; + + /* Floating Point Regs */ +#ifdef CONFIG_8260 + STFDM(ptr); + ptr += 32*2; +#else + for (i = 0; i < 32; i++) { + *ptr++ = 0; + *ptr++ = 0; + } +#endif + + /* pc, msr, cr, lr, ctr, xer, (mq is unused) */ + *ptr++ = regs->nip; + *ptr++ = regs->msr; + *ptr++ = regs->ccr; + *ptr++ = regs->link; + *ptr++ = regs->ctr; + *ptr++ = regs->xer; + + return (SPACE_REQUIRED); +} + +/* set the value of the CPU registers */ + +#ifdef CONFIG_8260 +/* load floating double */ +#define LFD(n,v) __asm__ __volatile__ ("lfd " #n ",%0" :: "o"(v)) +/* load floating double indexed */ +#define LFDI(n,p) __asm__ __volatile__ ("lfd " #n ",%0" :: "o"((p)[2*n])) +/* load floating double multiple */ +#define LFDM(p) { LFDI( 0,p); LFDI( 1,p); LFDI( 2,p); LFDI( 3,p); \ + LFDI( 4,p); LFDI( 5,p); LFDI( 6,p); LFDI( 7,p); \ + LFDI( 8,p); LFDI( 9,p); LFDI(10,p); LFDI(11,p); \ + LFDI(12,p); LFDI(13,p); LFDI(14,p); LFDI(15,p); \ + LFDI(16,p); LFDI(17,p); LFDI(18,p); LFDI(19,p); \ + LFDI(20,p); LFDI(21,p); LFDI(22,p); LFDI(23,p); \ + LFDI(24,p); LFDI(25,p); LFDI(26,p); LFDI(27,p); \ + LFDI(28,p); LFDI(29,p); LFDI(30,p); LFDI(31,p); } +#endif + +void +kgdb_putreg(struct pt_regs *regs, int regno, char *buf, int length) +{ + unsigned long *ptr = (unsigned long *)buf; + + if (regno < 0 || regno >= 70) + kgdb_error(KGDBERR_BADPARAMS); + else if (regno >= 32 && regno < 64) { + if (length < 8) + kgdb_error(KGDBERR_NOSPACE); + } + else { + if (length < 4) + kgdb_error(KGDBERR_NOSPACE); + } + + if ((unsigned long)ptr & 3) + kgdb_error(KGDBERR_ALIGNFAULT); + + if (regno >= 0 && regno < 32) + regs->gpr[regno] = *ptr; + else switch (regno) { + +#ifdef CONFIG_8260 +#define caseF(n) \ + case (n) + 32: LFD(n, *ptr); break; + +caseF( 0) caseF( 1) caseF( 2) caseF( 3) caseF( 4) caseF( 5) caseF( 6) caseF( 7) +caseF( 8) caseF( 9) caseF(10) caseF(11) caseF(12) caseF(13) caseF(14) caseF(15) +caseF(16) caseF(17) caseF(18) caseF(19) caseF(20) caseF(21) caseF(22) caseF(23) +caseF(24) caseF(25) caseF(26) caseF(27) caseF(28) caseF(29) caseF(30) caseF(31) + +#undef caseF +#endif + + case 64: regs->nip = *ptr; break; + case 65: regs->msr = *ptr; break; + case 66: regs->ccr = *ptr; break; + case 67: regs->link = *ptr; break; + case 68: regs->ctr = *ptr; break; + case 69: regs->ctr = *ptr; break; + + default: + kgdb_error(KGDBERR_BADPARAMS); + } +} + +void +kgdb_putregs(struct pt_regs *regs, char *buf, int length) +{ + int i; + unsigned long *ptr = (unsigned long *)buf; + + if (length < SPACE_REQUIRED) + kgdb_error(KGDBERR_NOSPACE); + + if ((unsigned long)ptr & 3) + kgdb_error(KGDBERR_ALIGNFAULT); + + /* + * If the stack pointer has moved, you should pray. + * (cause only god can help you). + */ + + /* General Purpose Regs */ + for (i = 0; i < 32; i++) + regs->gpr[i] = *ptr++; + + /* Floating Point Regs */ +#ifdef CONFIG_8260 + LFDM(ptr); +#endif + ptr += 32*2; + + /* pc, msr, cr, lr, ctr, xer, (mq is unused) */ + regs->nip = *ptr++; + regs->msr = *ptr++; + regs->ccr = *ptr++; + regs->link = *ptr++; + regs->ctr = *ptr++; + regs->xer = *ptr++; +} + +/* 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 +kgdb_breakpoint(int argc, char *argv[]) +{ + asm(" .globl breakinst\n\ + breakinst: .long 0x7d821008\n\ + "); +} + +#endif /* CFG_CMD_KGDB */ |