Linux-2.6.12-rc2v2.6.12-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!

1 files changed, 2506 insertions, 0 deletions

diff --git a/arch/ppc64/xmon/xmon.c b/arch/ppc64/xmon/xmon.c
new file mode 100644
index 00000000000..3c0ccb2623a
--- /dev/null
+++ b/arch/ppc64/xmon/xmon.c
@@ -0,0 +1,2506 @@
+/*
+ * Routines providing a simple monitor for use on the PowerMac.
+ *
+ * Copyright (C) 1996 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 <linux/config.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/smp.h>
+#include <linux/mm.h>
+#include <linux/reboot.h>
+#include <linux/delay.h>
+#include <linux/kallsyms.h>
+#include <linux/cpumask.h>
+
+#include <asm/ptrace.h>
+#include <asm/string.h>
+#include <asm/prom.h>
+#include <asm/machdep.h>
+#include <asm/processor.h>
+#include <asm/pgtable.h>
+#include <asm/mmu.h>
+#include <asm/mmu_context.h>
+#include <asm/paca.h>
+#include <asm/ppcdebug.h>
+#include <asm/cputable.h>
+#include <asm/rtas.h>
+#include <asm/sstep.h>
+#include <asm/bug.h>
+#include <asm/hvcall.h>
+
+#include "nonstdio.h"
+#include "privinst.h"
+
+#define scanhex	xmon_scanhex
+#define skipbl	xmon_skipbl
+
+#ifdef CONFIG_SMP
+cpumask_t cpus_in_xmon = CPU_MASK_NONE;
+static unsigned long xmon_taken = 1;
+static int xmon_owner;
+static int xmon_gate;
+#endif /* CONFIG_SMP */
+
+static unsigned long in_xmon = 0;
+
+static unsigned long adrs;
+static int size = 1;
+#define MAX_DUMP (128 * 1024)
+static unsigned long ndump = 64;
+static unsigned long nidump = 16;
+static unsigned long ncsum = 4096;
+static int termch;
+static char tmpstr[128];
+
+#define JMP_BUF_LEN	(184/sizeof(long))
+static long bus_error_jmp[JMP_BUF_LEN];
+static int catch_memory_errors;
+static long *xmon_fault_jmp[NR_CPUS];
+#define setjmp xmon_setjmp
+#define longjmp xmon_longjmp
+
+/* Breakpoint stuff */
+struct bpt {
+	unsigned long	address;
+	unsigned int	instr[2];
+	atomic_t	ref_count;
+	int		enabled;
+	unsigned long	pad;
+};
+
+/* Bits in bpt.enabled */
+#define BP_IABR_TE	1		/* IABR translation enabled */
+#define BP_IABR		2
+#define BP_TRAP		8
+#define BP_DABR		0x10
+
+#define NBPTS	256
+static struct bpt bpts[NBPTS];
+static struct bpt dabr;
+static struct bpt *iabr;
+static unsigned bpinstr = 0x7fe00008;	/* trap */
+
+#define BP_NUM(bp)	((bp) - bpts + 1)
+
+/* Prototypes */
+static int cmds(struct pt_regs *);
+static int mread(unsigned long, void *, int);
+static int mwrite(unsigned long, void *, int);
+static int handle_fault(struct pt_regs *);
+static void byterev(unsigned char *, int);
+static void memex(void);
+static int bsesc(void);
+static void dump(void);
+static void prdump(unsigned long, long);
+static int ppc_inst_dump(unsigned long, long, int);
+void print_address(unsigned long);
+static void backtrace(struct pt_regs *);
+static void excprint(struct pt_regs *);
+static void prregs(struct pt_regs *);
+static void memops(int);
+static void memlocate(void);
+static void memzcan(void);
+static void memdiffs(unsigned char *, unsigned char *, unsigned, unsigned);
+int skipbl(void);
+int scanhex(unsigned long *valp);
+static void scannl(void);
+static int hexdigit(int);
+void getstring(char *, int);
+static void flush_input(void);
+static int inchar(void);
+static void take_input(char *);
+static unsigned long read_spr(int);
+static void write_spr(int, unsigned long);
+static void super_regs(void);
+static void remove_bpts(void);
+static void insert_bpts(void);
+static void remove_cpu_bpts(void);
+static void insert_cpu_bpts(void);
+static struct bpt *at_breakpoint(unsigned long pc);
+static struct bpt *in_breakpoint_table(unsigned long pc, unsigned long *offp);
+static int  do_step(struct pt_regs *);
+static void bpt_cmds(void);
+static void cacheflush(void);
+static int  cpu_cmd(void);
+static void csum(void);
+static void bootcmds(void);
+void dump_segments(void);
+static void symbol_lookup(void);
+static void xmon_print_symbol(unsigned long address, const char *mid,
+			      const char *after);
+static const char *getvecname(unsigned long vec);
+
+static void debug_trace(void);
+
+extern int print_insn_powerpc(unsigned long, unsigned long, int);
+extern void printf(const char *fmt, ...);
+extern void xmon_vfprintf(void *f, const char *fmt, va_list ap);
+extern int xmon_putc(int c, void *f);
+extern int putchar(int ch);
+extern int xmon_read_poll(void);
+extern int setjmp(long *);
+extern void longjmp(long *, int);
+extern unsigned long _ASR;
+
+#define GETWORD(v)	(((v)[0] << 24) + ((v)[1] << 16) + ((v)[2] << 8) + (v)[3])
+
+#define isxdigit(c)	(('0' <= (c) && (c) <= '9') \
+			 || ('a' <= (c) && (c) <= 'f') \
+			 || ('A' <= (c) && (c) <= 'F'))
+#define isalnum(c)	(('0' <= (c) && (c) <= '9') \
+			 || ('a' <= (c) && (c) <= 'z') \
+			 || ('A' <= (c) && (c) <= 'Z'))
+#define isspace(c)	(c == ' ' || c == '\t' || c == 10 || c == 13 || c == 0)
+
+static char *help_string = "\
+Commands:\n\
+  b	show breakpoints\n\
+  bd	set data breakpoint\n\
+  bi	set instruction breakpoint\n\
+  bc	clear breakpoint\n"
+#ifdef CONFIG_SMP
+  "\
+  c	print cpus stopped in xmon\n\
+  c#	try to switch to cpu number h (in hex)\n"
+#endif
+  "\
+  C	checksum\n\
+  d	dump bytes\n\
+  di	dump instructions\n\
+  df	dump float values\n\
+  dd	dump double values\n\
+  e	print exception information\n\
+  f	flush cache\n\
+  la	lookup symbol+offset of specified address\n\
+  ls	lookup address of specified symbol\n\
+  m	examine/change memory\n\
+  mm	move a block of memory\n\
+  ms	set a block of memory\n\
+  md	compare two blocks of memory\n\
+  ml	locate a block of memory\n\
+  mz	zero a block of memory\n\
+  mi	show information about memory allocation\n\
+  p 	show the task list\n\
+  r	print registers\n\
+  s	single step\n\
+  S	print special registers\n\
+  t	print backtrace\n\
+  T	Enable/Disable PPCDBG flags\n\
+  x	exit monitor and recover\n\
+  X	exit monitor and dont recover\n\
+  u	dump segment table or SLB\n\
+  ?	help\n"
+  "\
+  zr	reboot\n\
+  zh	halt\n"
+;
+
+static struct pt_regs *xmon_regs;
+
+extern inline void sync(void)
+{
+	asm volatile("sync; isync");
+}
+
+/* (Ref: 64-bit PowerPC ELF ABI Spplement; Ian Lance Taylor, Zembu Labs).
+ A PPC stack frame looks like this:
+
+ High Address
+    Back Chain
+    FP reg save area
+    GP reg save area
+    Local var space
+    Parameter save area		(SP+48)
+    TOC save area		(SP+40)
+    link editor doubleword	(SP+32)
+    compiler doubleword		(SP+24)
+    LR save			(SP+16)
+    CR save			(SP+8)
+    Back Chain			(SP+0)
+
+ Note that the LR (ret addr) may not be saved in the current frame if
+ no functions have been called from the current function.
+ */
+
+/*
+ * Disable surveillance (the service processor watchdog function)
+ * while we are in xmon.
+ * XXX we should re-enable it when we leave. :)
+ */
+#define SURVEILLANCE_TOKEN	9000
+
+static inline void disable_surveillance(void)
+{
+#ifdef CONFIG_PPC_PSERIES
+	/* Since this can't be a module, args should end up below 4GB. */
+	static struct rtas_args args;
+
+	/*
+	 * At this point we have got all the cpus we can into
+	 * xmon, so there is hopefully no other cpu calling RTAS
+	 * at the moment, even though we don't take rtas.lock.
+	 * If we did try to take rtas.lock there would be a
+	 * real possibility of deadlock.
+	 */
+	args.token = rtas_token("set-indicator");
+	if (args.token == RTAS_UNKNOWN_SERVICE)
+		return;
+	args.nargs = 3;
+	args.nret = 1;
+	args.rets = &args.args[3];
+	args.args[0] = SURVEILLANCE_TOKEN;
+	args.args[1] = 0;
+	args.args[2] = 0;
+	enter_rtas(__pa(&args));
+#endif /* CONFIG_PPC_PSERIES */
+}
+
+#ifdef CONFIG_SMP
+static int xmon_speaker;
+
+static void get_output_lock(void)
+{
+	int me = smp_processor_id() + 0x100;
+	int last_speaker = 0, prev;
+	long timeout;
+
+	if (xmon_speaker == me)
+		return;
+	for (;;) {
+		if (xmon_speaker == 0) {
+			last_speaker = cmpxchg(&xmon_speaker, 0, me);
+			if (last_speaker == 0)
+				return;
+		}
+		timeout = 10000000;
+		while (xmon_speaker == last_speaker) {
+			if (--timeout > 0)
+				continue;
+			/* hostile takeover */
+			prev = cmpxchg(&xmon_speaker, last_speaker, me);
+			if (prev == last_speaker)
+				return;
+			break;
+		}
+	}
+}
+
+static void release_output_lock(void)
+{
+	xmon_speaker = 0;
+}
+#endif
+
+int xmon_core(struct pt_regs *regs, int fromipi)
+{
+	int cmd = 0;
+	unsigned long msr;
+	struct bpt *bp;
+	long recurse_jmp[JMP_BUF_LEN];
+	unsigned long offset;
+#ifdef CONFIG_SMP
+	int cpu;
+	int secondary;
+	unsigned long timeout;
+#endif
+
+	msr = get_msr();
+	set_msrd(msr & ~MSR_EE);	/* disable interrupts */
+
+	bp = in_breakpoint_table(regs->nip, &offset);
+	if (bp != NULL) {
+		regs->nip = bp->address + offset;
+		atomic_dec(&bp->ref_count);
+	}
+
+	remove_cpu_bpts();
+
+#ifdef CONFIG_SMP
+	cpu = smp_processor_id();
+	if (cpu_isset(cpu, cpus_in_xmon)) {
+		get_output_lock();
+		excprint(regs);
+		printf("cpu 0x%x: Exception %lx %s in xmon, "
+		       "returning to main loop\n",
+		       cpu, regs->trap, getvecname(TRAP(regs)));
+		longjmp(xmon_fault_jmp[cpu], 1);
+	}
+
+	if (setjmp(recurse_jmp) != 0) {
+		if (!in_xmon || !xmon_gate) {
+			printf("xmon: WARNING: bad recursive fault "
+			       "on cpu 0x%x\n", cpu);
+			goto waiting;
+		}
+		secondary = !(xmon_taken && cpu == xmon_owner);
+		goto cmdloop;
+	}
+
+	xmon_fault_jmp[cpu] = recurse_jmp;
+	cpu_set(cpu, cpus_in_xmon);
+
+	bp = NULL;
+	if ((regs->msr & (MSR_IR|MSR_PR|MSR_SF)) == (MSR_IR|MSR_SF))
+		bp = at_breakpoint(regs->nip);
+	if (bp || (regs->msr & MSR_RI) == 0)
+		fromipi = 0;
+
+	if (!fromipi) {
+		get_output_lock();
+		excprint(regs);
+		if (bp) {
+			printf("cpu 0x%x stopped at breakpoint 0x%x (",
+			       cpu, BP_NUM(bp));
+			xmon_print_symbol(regs->nip, " ", ")\n");
+		}
+		if ((regs->msr & MSR_RI) == 0)
+			printf("WARNING: exception is not recoverable, "
+			       "can't continue\n");
+		release_output_lock();
+	}
+
+ waiting:
+	secondary = 1;
+	while (secondary && !xmon_gate) {
+		if (in_xmon == 0) {
+			if (fromipi)
+				goto leave;
+			secondary = test_and_set_bit(0, &in_xmon);
+		}
+		barrier();
+	}
+
+	if (!secondary && !xmon_gate) {
+		/* we are the first cpu to come in */
+		/* interrupt other cpu(s) */
+		int ncpus = num_online_cpus();
+
+		xmon_owner = cpu;
+		mb();
+		if (ncpus > 1) {
+			smp_send_debugger_break(MSG_ALL_BUT_SELF);
+			/* wait for other cpus to come in */
+			for (timeout = 100000000; timeout != 0; --timeout) {
+				if (cpus_weight(cpus_in_xmon) >= ncpus)
+					break;
+				barrier();
+			}
+		}
+		remove_bpts();
+		disable_surveillance();
+		/* for breakpoint or single step, print the current instr. */
+		if (bp || TRAP(regs) == 0xd00)
+			ppc_inst_dump(regs->nip, 1, 0);
+		printf("enter ? for help\n");
+		mb();
+		xmon_gate = 1;
+		barrier();
+	}
+
+ cmdloop:
+	while (in_xmon) {
+		if (secondary) {
+			if (cpu == xmon_owner) {
+				if (!test_and_set_bit(0, &xmon_taken)) {
+					secondary = 0;
+					continue;
+				}
+				/* missed it */
+				while (cpu == xmon_owner)
+					barrier();
+			}
+			barrier();
+		} else {
+			cmd = cmds(regs);
+			if (cmd != 0) {
+				/* exiting xmon */
+				insert_bpts();
+				xmon_gate = 0;
+				wmb();
+				in_xmon = 0;
+				break;
+			}
+			/* have switched to some other cpu */
+			secondary = 1;
+		}
+	}
+ leave:
+	cpu_clear(cpu, cpus_in_xmon);
+	xmon_fault_jmp[cpu] = NULL;
+
+#else
+	/* UP is simple... */
+	if (in_xmon) {
+		printf("Exception %lx %s in xmon, returning to main loop\n",
+		       regs->trap, getvecname(TRAP(regs)));
+		longjmp(xmon_fault_jmp[0], 1);
+	}
+	if (setjmp(recurse_jmp) == 0) {
+		xmon_fault_jmp[0] = recurse_jmp;
+		in_xmon = 1;
+
+		excprint(regs);
+		bp = at_breakpoint(regs->nip);
+		if (bp) {
+			printf("Stopped at breakpoint %x (", BP_NUM(bp));
+			xmon_print_symbol(regs->nip, " ", ")\n");
+		}
+		if ((regs->msr & MSR_RI) == 0)
+			printf("WARNING: exception is not recoverable, "
+			       "can't continue\n");
+		remove_bpts();
+		disable_surveillance();
+		/* for breakpoint or single step, print the current instr. */
+		if (bp || TRAP(regs) == 0xd00)
+			ppc_inst_dump(regs->nip, 1, 0);
+		printf("enter ? for help\n");
+	}
+
+	cmd = cmds(regs);
+
+	insert_bpts();
+	in_xmon = 0;
+#endif
+
+	if ((regs->msr & (MSR_IR|MSR_PR|MSR_SF)) == (MSR_IR|MSR_SF)) {
+		bp = at_breakpoint(regs->nip);
+		if (bp != NULL) {
+			int stepped = emulate_step(regs, bp->instr[0]);
+			if (stepped == 0) {
+				regs->nip = (unsigned long) &bp->instr[0];
+				atomic_inc(&bp->ref_count);
+			} else if (stepped < 0) {
+				printf("Couldn't single-step %s instruction\n",
+				    (IS_RFID(bp->instr[0])? "rfid": "mtmsrd"));
+			}
+		}
+	}
+
+	insert_cpu_bpts();
+
+	set_msrd(msr);		/* restore interrupt enable */
+
+	return cmd != 'X';
+}
+
+int xmon(struct pt_regs *excp)
+{
+	struct pt_regs regs;
+
+	if (excp == NULL) {
+		/* Ok, grab regs as they are now.
+		 This won't do a particularily good job because the
+		 prologue has already been executed.
+		 ToDo: We could reach back into the callers save
+		 area to do a better job of representing the
+		 caller's state.
+		 */
+		asm volatile ("std	0,0(%0)\n\
+			std	1,8(%0)\n\
+			std	2,16(%0)\n\
+			std	3,24(%0)\n\
+			std	4,32(%0)\n\
+			std	5,40(%0)\n\
+			std	6,48(%0)\n\
+			std	7,56(%0)\n\
+			std	8,64(%0)\n\
+			std	9,72(%0)\n\
+			std	10,80(%0)\n\
+			std	11,88(%0)\n\
+			std	12,96(%0)\n\
+			std	13,104(%0)\n\
+			std	14,112(%0)\n\
+			std	15,120(%0)\n\
+			std	16,128(%0)\n\
+			std	17,136(%0)\n\
+			std	18,144(%0)\n\
+			std	19,152(%0)\n\
+			std	20,160(%0)\n\
+			std	21,168(%0)\n\
+			std	22,176(%0)\n\
+			std	23,184(%0)\n\
+			std	24,192(%0)\n\
+			std	25,200(%0)\n\
+			std	26,208(%0)\n\
+			std	27,216(%0)\n\
+			std	28,224(%0)\n\
+			std	29,232(%0)\n\
+			std	30,240(%0)\n\
+			std	31,248(%0)" : : "b" (&regs));
+
+		regs.nip = regs.link = ((unsigned long *)(regs.gpr[1]))[2];
+		regs.msr = get_msr();
+		regs.ctr = get_ctr();
+		regs.xer = get_xer();
+		regs.ccr = get_cr();
+		regs.trap = 0;
+		excp = &regs;
+	}
+	return xmon_core(excp, 0);
+}
+
+int xmon_bpt(struct pt_regs *regs)
+{
+	struct bpt *bp;
+	unsigned long offset;
+
+	if ((regs->msr & (MSR_IR|MSR_PR|MSR_SF)) != (MSR_IR|MSR_SF))
+		return 0;
+
+	/* Are we at the trap at bp->instr[1] for some bp? */
+	bp = in_breakpoint_table(regs->nip, &offset);
+	if (bp != NULL && offset == 4) {
+		regs->nip = bp->address + 4;
+		atomic_dec(&bp->ref_count);
+		return 1;
+	}
+
+	/* Are we at a breakpoint? */
+	bp = at_breakpoint(regs->nip);
+	if (!bp)
+		return 0;
+
+	xmon_core(regs, 0);
+
+	return 1;
+}
+
+int xmon_sstep(struct pt_regs *regs)
+{
+	if (user_mode(regs))
+		return 0;
+	xmon_core(regs, 0);
+	return 1;
+}
+
+int xmon_dabr_match(struct pt_regs *regs)
+{
+	if ((regs->msr & (MSR_IR|MSR_PR|MSR_SF)) != (MSR_IR|MSR_SF))
+		return 0;
+	xmon_core(regs, 0);
+	return 1;
+}
+
+int xmon_iabr_match(struct pt_regs *regs)
+{
+	if ((regs->msr & (MSR_IR|MSR_PR|MSR_SF)) != (MSR_IR|MSR_SF))
+		return 0;
+	if (iabr == 0)
+		return 0;
+	xmon_core(regs, 0);
+	return 1;
+}
+
+int xmon_ipi(struct pt_regs *regs)
+{
+#ifdef CONFIG_SMP
+	if (in_xmon && !cpu_isset(smp_processor_id(), cpus_in_xmon))
+		xmon_core(regs, 1);
+#endif
+	return 0;
+}
+
+int xmon_fault_handler(struct pt_regs *regs)
+{
+	struct bpt *bp;
+	unsigned long offset;
+
+	if (in_xmon && catch_memory_errors)
+		handle_fault(regs);	/* doesn't return */
+
+	if ((regs->msr & (MSR_IR|MSR_PR|MSR_SF)) == (MSR_IR|MSR_SF)) {
+		bp = in_breakpoint_table(regs->nip, &offset);
+		if (bp != NULL) {
+			regs->nip = bp->address + offset;
+			atomic_dec(&bp->ref_count);
+		}
+	}
+
+	return 0;
+}
+
+/* On systems with a hypervisor, we can't set the DABR
+   (data address breakpoint register) directly. */
+static void set_controlled_dabr(unsigned long val)
+{
+#ifdef CONFIG_PPC_PSERIES
+	if (systemcfg->platform == PLATFORM_PSERIES_LPAR) {
+		int rc = plpar_hcall_norets(H_SET_DABR, val);
+		if (rc != H_Success)
+			xmon_printf("Warning: setting DABR failed (%d)\n", rc);
+	} else
+#endif
+		set_dabr(val);
+}
+
+static struct bpt *at_breakpoint(unsigned long pc)
+{
+	int i;
+	struct bpt *bp;
+
+	bp = bpts;
+	for (i = 0; i < NBPTS; ++i, ++bp)
+		if (bp->enabled && pc == bp->address)
+			return bp;
+	return NULL;
+}
+
+static struct bpt *in_breakpoint_table(unsigned long nip, unsigned long *offp)
+{
+	unsigned long off;
+
+	off = nip - (unsigned long) bpts;
+	if (off >= sizeof(bpts))
+		return NULL;
+	off %= sizeof(struct bpt);
+	if (off != offsetof(struct bpt, instr[0])
+	    && off != offsetof(struct bpt, instr[1]))
+		return NULL;
+	*offp = off - offsetof(struct bpt, instr[0]);
+	return (struct bpt *) (nip - off);
+}
+
+static struct bpt *new_breakpoint(unsigned long a)
+{
+	struct bpt *bp;
+
+	a &= ~3UL;
+	bp = at_breakpoint(a);
+	if (bp)
+		return bp;
+
+	for (bp = bpts; bp < &bpts[NBPTS]; ++bp) {
+		if (!bp->enabled && atomic_read(&bp->ref_count) == 0) {
+			bp->address = a;
+			bp->instr[1] = bpinstr;
+			store_inst(&bp->instr[1]);
+			return bp;
+		}
+	}
+
+	printf("Sorry, no free breakpoints.  Please clear one first.\n");
+	return NULL;
+}
+
+static void insert_bpts(void)
+{
+	int i;
+	struct bpt *bp;
+
+	bp = bpts;
+	for (i = 0; i < NBPTS; ++i, ++bp) {
+		if ((bp->enabled & (BP_TRAP|BP_IABR)) == 0)
+			continue;
+		if (mread(bp->address, &bp->instr[0], 4) != 4) {
+			printf("Couldn't read instruction at %lx, "
+			       "disabling breakpoint there\n", bp->address);
+			bp->enabled = 0;
+			continue;
+		}
+		if (IS_MTMSRD(bp->instr[0]) || IS_RFID(bp->instr[0])) {
+			printf("Breakpoint at %lx is on an mtmsrd or rfid "
+			       "instruction, disabling it\n", bp->address);
+			bp->enabled = 0;
+			continue;
+		}
+		store_inst(&bp->instr[0]);
+		if (bp->enabled & BP_IABR)
+			continue;
+		if (mwrite(bp->address, &bpinstr, 4) != 4) {
+			printf("Couldn't write instruction at %lx, "
+			       "disabling breakpoint there\n", bp->address);
+			bp->enabled &= ~BP_TRAP;
+			continue;
+		}
+		store_inst((void *)bp->address);
+	}
+}
+
+static void insert_cpu_bpts(void)
+{
+	if (dabr.enabled)
+		set_controlled_dabr(dabr.address | (dabr.enabled & 7));
+	if (iabr && cpu_has_feature(CPU_FTR_IABR))
+		set_iabr(iabr->address
+			 | (iabr->enabled & (BP_IABR|BP_IABR_TE)));
+}
+
+static void remove_bpts(void)
+{
+	int i;
+	struct bpt *bp;
+	unsigned instr;
+
+	bp = bpts;
+	for (i = 0; i < NBPTS; ++i, ++bp) {
+		if ((bp->enabled & (BP_TRAP|BP_IABR)) != BP_TRAP)
+			continue;
+		if (mread(bp->address, &instr, 4) == 4
+		    && instr == bpinstr
+		    && mwrite(bp->address, &bp->instr, 4) != 4)
+			printf("Couldn't remove breakpoint at %lx\n",
+			       bp->address);
+		else
+			store_inst((void *)bp->address);
+	}
+}
+
+static void remove_cpu_bpts(void)
+{
+	set_controlled_dabr(0);
+	if (cpu_has_feature(CPU_FTR_IABR))
+		set_iabr(0);
+}
+
+/* Command interpreting routine */
+static char *last_cmd;
+
+static int
+cmds(struct pt_regs *excp)
+{
+	int cmd = 0;
+
+	last_cmd = NULL;
+	xmon_regs = excp;
+	for(;;) {
+#ifdef CONFIG_SMP
+		printf("%x:", smp_processor_id());
+#endif /* CONFIG_SMP */
+		printf("mon> ");
+		fflush(stdout);
+		flush_input();
+		termch = 0;
+		cmd = skipbl();
+		if( cmd == '\n' ) {
+			if (last_cmd == NULL)
+				continue;
+			take_input(last_cmd);
+			last_cmd = NULL;
+			cmd = inchar();
+		}
+		switch (cmd) {
+		case 'm':
+			cmd = inchar();
+			switch (cmd) {
+			case 'm':
+			case 's':
+			case 'd':
+				memops(cmd);
+				break;
+			case 'l':
+				memlocate();
+				break;
+			case 'z':
+				memzcan();
+				break;
+			case 'i':
+				show_mem();
+				break;
+			default:
+				termch = cmd;
+				memex();
+			}
+			break;
+		case 'd':
+			dump();
+			break;
+		case 'l':
+			symbol_lookup();
+			break;
+		case 'r':
+			prregs(excp);	/* print regs */
+			break;
+		case 'e':
+			excprint(excp);
+			break;
+		case 'S':
+			super_regs();
+			break;
+		case 't':
+			backtrace(excp);
+			break;
+		case 'f':
+			cacheflush();
+			break;
+		case 's':
+			if (do_step(excp))
+				return cmd;
+			break;
+		case 'x':
+		case 'X':
+		case EOF:
+			return cmd;
+		case '?':
+			printf(help_string);
+			break;
+		case 'p':
+			show_state();
+			break;
+		case 'b':
+			bpt_cmds();
+			break;
+		case 'C':
+			csum();
+			break;
+		case 'c':
+			if (cpu_cmd())
+				return 0;
+			break;
+		case 'z':
+			bootcmds();
+			break;
+		case 'T':
+			debug_trace();
+			break;
+		case 'u':
+			dump_segments();
+			break;
+		default:
+			printf("Unrecognized command: ");
+		        do {
+				if (' ' < cmd && cmd <= '~')
+					putchar(cmd);
+				else
+					printf("\\x%x", cmd);
+				cmd = inchar();
+		        } while (cmd != '\n'); 
+			printf(" (type ? for help)\n");
+			break;
+		}
+	}
+}
+
+/*
+ * Step a single instruction.
+ * Some instructions we emulate, others we execute with MSR_SE set.
+ */
+static int do_step(struct pt_regs *regs)
+{
+	unsigned int instr;
+	int stepped;
+
+	/* check we are in 64-bit kernel mode, translation enabled */
+	if ((regs->msr & (MSR_SF|MSR_PR|MSR_IR)) == (MSR_SF|MSR_IR)) {
+		if (mread(regs->nip, &instr, 4) == 4) {
+			stepped = emulate_step(regs, instr);
+			if (stepped < 0) {
+				printf("Couldn't single-step %s instruction\n",
+				       (IS_RFID(instr)? "rfid": "mtmsrd"));
+				return 0;
+			}
+			if (stepped > 0) {
+				regs->trap = 0xd00 | (regs->trap & 1);
+				printf("stepped to ");
+				xmon_print_symbol(regs->nip, " ", "\n");
+				ppc_inst_dump(regs->nip, 1, 0);
+				return 0;
+			}
+		}
+	}
+	regs->msr |= MSR_SE;
+	return 1;
+}
+
+static void bootcmds(void)
+{
+	int cmd;
+
+	cmd = inchar();
+	if (cmd == 'r')
+		ppc_md.restart(NULL);
+	else if (cmd == 'h')
+		ppc_md.halt();
+	else if (cmd == 'p')
+		ppc_md.power_off();
+}
+
+static int cpu_cmd(void)
+{
+#ifdef CONFIG_SMP
+	unsigned long cpu;
+	int timeout;
+	int count;
+
+	if (!scanhex(&cpu)) {
+		/* print cpus waiting or in xmon */
+		printf("cpus stopped:");
+		count = 0;
+		for (cpu = 0; cpu < NR_CPUS; ++cpu) {
+			if (cpu_isset(cpu, cpus_in_xmon)) {
+				if (count == 0)
+					printf(" %x", cpu);
+				++count;
+			} else {
+				if (count > 1)
+					printf("-%x", cpu - 1);
+				count = 0;
+			}
+		}
+		if (count > 1)
+			printf("-%x", NR_CPUS - 1);
+		printf("\n");
+		return 0;
+	}
+	/* try to switch to cpu specified */
+	if (!cpu_isset(cpu, cpus_in_xmon)) {
+		printf("cpu 0x%x isn't in xmon\n", cpu);
+		return 0;
+	}
+	xmon_taken = 0;
+	mb();
+	xmon_owner = cpu;
+	timeout = 10000000;
+	while (!xmon_taken) {
+		if (--timeout == 0) {
+			if (test_and_set_bit(0, &xmon_taken))
+				break;
+			/* take control back */
+			mb();
+			xmon_owner = smp_processor_id();
+			printf("cpu %u didn't take control\n", cpu);
+			return 0;
+		}
+		barrier();
+	}
+	return 1;
+#else
+	return 0;
+#endif /* CONFIG_SMP */
+}
+
+static unsigned short fcstab[256] = {
+	0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf,
+	0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7,
+	0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e,
+	0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876,
+	0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd,
+	0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5,
+	0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c,
+	0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974,
+	0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb,
+	0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3,
+	0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a,
+	0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72,
+	0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9,
+	0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1,
+	0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738,
+	0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70,
+	0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7,
+	0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff,
+	0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036,
+	0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e,
+	0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5,
+	0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd,
+	0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134,
+	0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c,
+	0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3,
+	0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb,
+	0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232,
+	0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a,
+	0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1,
+	0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9,
+	0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330,
+	0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78
+};
+
+#define FCS(fcs, c)	(((fcs) >> 8) ^ fcstab[((fcs) ^ (c)) & 0xff])
+
+static void
+csum(void)
+{
+	unsigned int i;
+	unsigned short fcs;
+	unsigned char v;
+
+	if (!scanhex(&adrs))
+		return;
+	if (!scanhex(&ncsum))
+		return;
+	fcs = 0xffff;
+	for (i = 0; i < ncsum; ++i) {
+		if (mread(adrs+i, &v, 1) == 0) {
+			printf("csum stopped at %x\n", adrs+i);
+			break;
+		}
+		fcs = FCS(fcs, v);
+	}
+	printf("%x\n", fcs);
+}
+
+/*
+ * Check if this is a suitable place to put a breakpoint.
+ */
+static long check_bp_loc(unsigned long addr)
+{
+	unsigned int instr;
+
+	addr &= ~3;
+	if (addr < KERNELBASE) {
+		printf("Breakpoints may only be placed at kernel addresses\n");
+		return 0;
+	}
+	if (!mread(addr, &instr, sizeof(instr))) {
+		printf("Can't read instruction at address %lx\n", addr);
+		return 0;
+	}
+	if (IS_MTMSRD(instr) || IS_RFID(instr)) {
+		printf("Breakpoints may not be placed on mtmsrd or rfid "
+		       "instructions\n");
+		return 0;
+	}
+	return 1;
+}
+
+static char *breakpoint_help_string = 
+    "Breakpoint command usage:\n"
+    "b                show breakpoints\n"
+    "b <addr> [cnt]   set breakpoint at given instr addr\n"
+    "bc               clear all breakpoints\n"
+    "bc <n/addr>      clear breakpoint number n or at addr\n"
+    "bi <addr> [cnt]  set hardware instr breakpoint (POWER3/RS64 only)\n"
+    "bd <addr> [cnt]  set hardware data breakpoint\n"
+    "";
+
+static void
+bpt_cmds(void)
+{
+	int cmd;
+	unsigned long a;
+	int mode, i;
+	struct bpt *bp;
+	const char badaddr[] = "Only kernel addresses are permitted "
+		"for breakpoints\n";
+
+	cmd = inchar();
+	switch (cmd) {
+	case 'd':	/* bd - hardware data breakpoint */
+		mode = 7;
+		cmd = inchar();
+		if (cmd == 'r')
+			mode = 5;
+		else if (cmd == 'w')
+			mode = 6;
+		else
+			termch = cmd;
+		dabr.address = 0;
+		dabr.enabled = 0;
+		if (scanhex(&dabr.address)) {
+			if (dabr.address < KERNELBASE) {
+				printf(badaddr);
+				break;
+			}
+			dabr.address &= ~7;
+			dabr.enabled = mode | BP_DABR;
+		}
+		break;
+
+	case 'i':	/* bi - hardware instr breakpoint */
+		if (!cpu_has_feature(CPU_FTR_IABR)) {
+			printf("Hardware instruction breakpoint "
+			       "not supported on this cpu\n");
+			break;
+		}
+		if (iabr) {
+			iabr->enabled &= ~(BP_IABR | BP_IABR_TE);
+			iabr = NULL;
+		}
+		if (!scanhex(&a))
+			break;
+		if (!check_bp_loc(a))
+			break;
+		bp = new_breakpoint(a);
+		if (bp != NULL) {
+			bp->enabled |= BP_IABR | BP_IABR_TE;
+			iabr = bp;
+		}
+		break;
+
+	case 'c':
+		if (!scanhex(&a)) {
+			/* clear all breakpoints */
+			for (i = 0; i < NBPTS; ++i)
+				bpts[i].enabled = 0;
+			iabr = NULL;
+			dabr.enabled = 0;
+			printf("All breakpoints cleared\n");
+			break;
+		}
+
+		if (a <= NBPTS && a >= 1) {
+			/* assume a breakpoint number */
+			bp = &bpts[a-1];	/* bp nums are 1 based */
+		} else {
+			/* assume a breakpoint address */
+			bp = at_breakpoint(a);
+			if (bp == 0) {
+				printf("No breakpoint at %x\n", a);
+				break;
+			}
+		}
+
+		printf("Cleared breakpoint %x (", BP_NUM(bp));
+		xmon_print_symbol(bp->address, " ", ")\n");
+		bp->enabled = 0;
+		break;
+
+	default:
+		termch = cmd;
+	        cmd = skipbl();
+		if (cmd == '?') {
+			printf(breakpoint_help_string);
+			break;
+		}
+		termch = cmd;
+		if (!scanhex(&a)) {
+			/* print all breakpoints */
+			printf("   type            address\n");
+			if (dabr.enabled) {
+				printf("   data   %.16lx  [", dabr.address);
+				if (dabr.enabled & 1)
+					printf("r");
+				if (dabr.enabled & 2)
+					printf("w");
+				printf("]\n");
+			}
+			for (bp = bpts; bp < &bpts[NBPTS]; ++bp) {
+				if (!bp->enabled)
+					continue;
+				printf("%2x %s   ", BP_NUM(bp),
+				    (bp->enabled & BP_IABR)? "inst": "trap");
+				xmon_print_symbol(bp->address, "  ", "\n");
+			}
+			break;
+		}
+
+		if (!check_bp_loc(a))
+			break;
+		bp = new_breakpoint(a);
+		if (bp != NULL)
+			bp->enabled |= BP_TRAP;
+		break;
+	}
+}
+
+/* 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 void get_function_bounds(unsigned long pc, unsigned long *startp,
+				unsigned long *endp)
+{
+	unsigned long size, offset;
+	const char *name;
+	char *modname;
+
+	*startp = *endp = 0;
+	if (pc == 0)
+		return;
+	if (setjmp(bus_error_jmp) == 0) {
+		catch_memory_errors = 1;
+		sync();
+		name = kallsyms_lookup(pc, &size, &offset, &modname, tmpstr);
+		if (name != NULL) {
+			*startp = pc - offset;
+			*endp = pc - offset + size;
+		}
+		sync();
+	}
+	catch_memory_errors = 0;