--- /dev/null
+/*
+ * Routines providing a simple monitor for use on the PowerMac.
+ *
+ * Copyright (C) 1996-2005 Paul Mackerras.
+ *
+ * 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; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <xen/config.h>
+#include <xen/lib.h>
+#include <xen/console.h>
+#include <xen/sched.h>
+
+/* Shamelessly lifted from Linux Xmon try to keep pristene */
+#ifdef __powerpc64__
+#define LRSAVE_OFFSET 0x10
+#define REG_FRAME_MARKER 0x7265677368657265ul /* "regshere" */
+#define MARKER_OFFSET 0x60
+#define REGS_OFFSET 0x70
+#define REG "%016lX"
+#else
+#define LRSAVE_OFFSET 4
+#define REG_FRAME_MARKER 0x72656773
+#define MARKER_OFFSET 8
+#define REGS_OFFSET 16
+#define REG "%08lX"
+#endif
+
+#define TRAP(regs) ((regs)->entry_vector & ~0xF)
+static int xmon_depth_to_print = 64;
+
+/* Very cheap human name for vector lookup. */
+static
+const char *getvecname(unsigned long vec)
+{
+ char *ret;
+
+ switch (vec) {
+ case 0x100: ret = "(System Reset)"; break;
+ case 0x200: ret = "(Machine Check)"; break;
+ case 0x300: ret = "(Data Access)"; break;
+ case 0x380: ret = "(Data SLB Access)"; break;
+ case 0x400: ret = "(Instruction Access)"; break;
+ case 0x480: ret = "(Instruction SLB Access)"; break;
+ case 0x500: ret = "(Hardware Interrupt)"; break;
+ case 0x600: ret = "(Alignment)"; break;
+ case 0x700: ret = "(Program Check)"; break;
+ case 0x800: ret = "(FPU Unavailable)"; break;
+ case 0x900: ret = "(Decrementer)"; break;
+ case 0xc00: ret = "(System Call)"; break;
+ case 0xd00: ret = "(Single Step)"; break;
+ case 0xf00: ret = "(Performance Monitor)"; break;
+ case 0xf20: ret = "(Altivec Unavailable)"; break;
+ case 0x1300: ret = "(Instruction Breakpoint)"; break;
+ default: ret = "";
+ }
+ return ret;
+}
+
+static int mread(unsigned long adrs, void *buf, int size)
+{
+ memcpy(buf, (void *)adrs, size);
+ return size;
+}
+
+static void get_function_bounds(unsigned long pc, unsigned long *startp,
+ unsigned long *endp)
+{
+ *startp = pc;
+ *endp = pc;
+}
+
+/* Print an address in numeric and symbolic form (if possible) */
+static void xmon_print_symbol(unsigned long address, const char *mid,
+ const char *after)
+{
+ char *modname;
+ const char *name = NULL;
+ unsigned long offset, size;
+
+ printf(REG, address);
+#if 0
+ if (setjmp(bus_error_jmp) == 0) {
+ catch_memory_errors = 1;
+ sync();
+ name = kallsyms_lookup(address, &size, &offset, &modname,
+ tmpstr);
+ sync();
+ /* wait a little while to see if we get a machine check */
+ __delay(200);
+ }
+
+ catch_memory_errors = 0;
+#endif
+ if (name) {
+ printf("%s%s+%#lx/%#lx", mid, name, offset, size);
+ if (modname)
+ printf(" [%s]", modname);
+ }
+ printf("%s", after);
+}
+
+static void backtrace(
+ unsigned long sp, unsigned long lr, unsigned long pc)
+{
+ unsigned long ip;
+ unsigned long newsp;
+ unsigned long marker;
+ int count = 0;
+ struct cpu_user_regs regs;
+
+ do {
+ if (sp > xenheap_phys_end) {
+ if (sp != 0)
+ printf("SP (%lx) is not in xen space\n", sp);
+ break;
+ }
+
+ if (!mread(sp + LRSAVE_OFFSET, &ip, sizeof(unsigned long))
+ || !mread(sp, &newsp, sizeof(unsigned long))) {
+ printf("Couldn't read stack frame at %lx\n", sp);
+ break;
+ }
+
+ /*
+ * For the first stack frame, try to work out if
+ * LR and/or the saved LR value in the bottommost
+ * stack frame are valid.
+ */
+ if ((pc | lr) != 0) {
+ unsigned long fnstart, fnend;
+ unsigned long nextip;
+ int printip = 1;
+
+ get_function_bounds(pc, &fnstart, &fnend);
+ nextip = 0;
+ if (newsp > sp)
+ mread(newsp + LRSAVE_OFFSET, &nextip,
+ sizeof(unsigned long));
+ if (lr == ip) {
+ if (lr >= xenheap_phys_end
+ || (fnstart <= lr && lr < fnend))
+ printip = 0;
+ } else if (lr == nextip) {
+ printip = 0;
+ } else if (lr < xenheap_phys_end
+ && !(fnstart <= lr && lr < fnend)) {
+ printf("[link register ] ");
+ xmon_print_symbol(lr, " ", "\n");
+ }
+ if (printip) {
+ printf("["REG"] ", sp);
+ xmon_print_symbol(ip, " ", " (unreliable)\n");
+ }
+ pc = lr = 0;
+
+ } else {
+ printf("["REG"] ", sp);
+ xmon_print_symbol(ip, " ", "\n");
+ }
+
+ /* Look for "regshere" marker to see if this is
+ an exception frame. */
+ if (mread(sp + MARKER_OFFSET, &marker, sizeof(unsigned long))
+ && marker == REG_FRAME_MARKER) {
+ if (mread(sp + REGS_OFFSET, ®s, sizeof(regs))
+ != sizeof(regs)) {
+ printf("Couldn't read registers at %lx\n",
+ sp + REGS_OFFSET);
+ break;
+ }
+ printf("--- Exception: %x %s at ", regs.entry_vector,
+ getvecname(TRAP(®s)));
+ pc = regs.pc;
+ lr = regs.lr;
+ xmon_print_symbol(pc, " ", "\n");
+ }
+
+ if (newsp == 0)
+ break;
+
+ sp = newsp;
+ } while (count++ < xmon_depth_to_print);
+}
+
+void show_backtrace(ulong sp, ulong lr, ulong pc)
+{
+ console_start_sync();
+ backtrace(sp, lr, pc);
+ console_end_sync();
+}
projects / xen.git / commitdiff