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-rw-r--r--lib_ppc/kgdb.c326
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 */