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#include <common.h>
#include <command.h>
#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)
{
unsigned long temp;
asm volatile("mflr %0; stw %0,0(%1);"
"stw %%r1,4(%1); stw %%r2,8(%1);"
"mfcr %0; stw %0,12(%1);"
"stmw %%r13,16(%1)"
: "=&r"(temp) : "r" (buf));
/* XXX should save fp regs as well */
return 0;
}
void
kgdb_longjmp(long *buf, int val)
{
unsigned long temp;
if (val == 0)
val = 1;
asm volatile("lmw %%r13,16(%1);"
"lwz %0,12(%1); mtcrf 0x38,%0;"
"lwz %0,0(%1); lwz %%r1,4(%1); lwz %%r2,8(%1);"
"mtlr %0; mr %%r3,%2"
: "=&r"(temp) : "r" (buf), "r" (val));
}
/* 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))
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 */
for (i = 0; i < 32; i++) {
*ptr++ = 0;
*ptr++ = 0;
}
/* 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 */
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) {
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 */
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 * const argv[])
{
asm(" .globl breakinst\n\
breakinst: .long 0x7d821008\n\
");
}
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