Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 4382 insertions, 0 deletions

diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c
new file mode 100644
index 000000000..cd692f399
--- /dev/null
+++ b/arch/powerpc/xmon/xmon.c
@@ -0,0 +1,4382 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Routines providing a simple monitor for use on the PowerMac.
+ *
+ * Copyright (C) 1996-2005 Paul Mackerras.
+ * Copyright (C) 2001 PPC64 Team, IBM Corp
+ * Copyrignt (C) 2006 Michael Ellerman, IBM Corp
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/sched/signal.h>
+#include <linux/smp.h>
+#include <linux/mm.h>
+#include <linux/reboot.h>
+#include <linux/delay.h>
+#include <linux/kallsyms.h>
+#include <linux/kmsg_dump.h>
+#include <linux/cpumask.h>
+#include <linux/export.h>
+#include <linux/sysrq.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/bug.h>
+#include <linux/nmi.h>
+#include <linux/ctype.h>
+#include <linux/highmem.h>
+#include <linux/security.h>
+#include <linux/debugfs.h>
+
+#include <asm/ptrace.h>
+#include <asm/smp.h>
+#include <asm/string.h>
+#include <asm/machdep.h>
+#include <asm/xmon.h>
+#include <asm/processor.h>
+#include <asm/mmu.h>
+#include <asm/mmu_context.h>
+#include <asm/plpar_wrappers.h>
+#include <asm/cputable.h>
+#include <asm/rtas.h>
+#include <asm/sstep.h>
+#include <asm/irq_regs.h>
+#include <asm/spu.h>
+#include <asm/spu_priv1.h>
+#include <asm/setjmp.h>
+#include <asm/reg.h>
+#include <asm/debug.h>
+#include <asm/hw_breakpoint.h>
+#include <asm/xive.h>
+#include <asm/opal.h>
+#include <asm/firmware.h>
+#include <asm/code-patching.h>
+#include <asm/sections.h>
+#include <asm/inst.h>
+#include <asm/interrupt.h>
+
+#ifdef CONFIG_PPC64
+#include <asm/hvcall.h>
+#include <asm/paca.h>
+#include <asm/lppaca.h>
+#endif
+
+#include "nonstdio.h"
+#include "dis-asm.h"
+#include "xmon_bpts.h"
+
+#ifdef CONFIG_SMP
+static cpumask_t cpus_in_xmon = CPU_MASK_NONE;
+static unsigned long xmon_taken = 1;
+static int xmon_owner;
+static int xmon_gate;
+static int xmon_batch;
+static unsigned long xmon_batch_start_cpu;
+static cpumask_t xmon_batch_cpus = CPU_MASK_NONE;
+#else
+#define xmon_owner 0
+#endif /* CONFIG_SMP */
+
+#ifdef CONFIG_PPC_PSERIES
+static int set_indicator_token = RTAS_UNKNOWN_SERVICE;
+#endif
+static unsigned long in_xmon __read_mostly = 0;
+static int xmon_on = IS_ENABLED(CONFIG_XMON_DEFAULT);
+static bool xmon_is_ro = IS_ENABLED(CONFIG_XMON_DEFAULT_RO_MODE);
+
+static unsigned long adrs;
+static int size = 1;
+#define MAX_DUMP (64 * 1024)
+static unsigned long ndump = 64;
+#define MAX_IDUMP (MAX_DUMP >> 2)
+static unsigned long nidump = 16;
+static unsigned long ncsum = 4096;
+static int termch;
+static char tmpstr[KSYM_NAME_LEN];
+static int tracing_enabled;
+
+static long bus_error_jmp[JMP_BUF_LEN];
+static int catch_memory_errors;
+static int catch_spr_faults;
+static long *xmon_fault_jmp[NR_CPUS];
+
+/* Breakpoint stuff */
+struct bpt {
+	unsigned long	address;
+	u32		*instr;
+	atomic_t	ref_count;
+	int		enabled;
+	unsigned long	pad;
+};
+
+/* Bits in bpt.enabled */
+#define BP_CIABR	1
+#define BP_TRAP		2
+#define BP_DABR		4
+
+static struct bpt bpts[NBPTS];
+static struct bpt dabr[HBP_NUM_MAX];
+static struct bpt *iabr;
+static unsigned int bpinstr = PPC_RAW_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 mread_instr(unsigned long, ppc_inst_t *);
+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 show_pte(unsigned long);
+static void prdump(unsigned long, long);
+static int ppc_inst_dump(unsigned long, long, int);
+static void dump_log_buf(void);
+
+#ifdef CONFIG_SMP
+static int xmon_switch_cpu(unsigned long);
+static int xmon_batch_next_cpu(void);
+static int batch_cmds(struct pt_regs *);
+#endif
+
+#ifdef CONFIG_PPC_POWERNV
+static void dump_opal_msglog(void);
+#else
+static inline void dump_opal_msglog(void)
+{
+	printf("Machine is not running OPAL firmware.\n");
+}
+#endif
+
+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 int  read_spr(int, unsigned long *);
+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);
+static void proccall(void);
+static void show_tasks(void);
+void dump_segments(void);
+static void symbol_lookup(void);
+static void xmon_show_stack(unsigned long sp, unsigned long lr,
+			    unsigned long pc);
+static void xmon_print_symbol(unsigned long address, const char *mid,
+			      const char *after);
+static const char *getvecname(unsigned long vec);
+
+static int do_spu_cmd(void);
+
+#ifdef CONFIG_44x
+static void dump_tlb_44x(void);
+#endif
+#ifdef CONFIG_PPC_BOOK3E_64
+static void dump_tlb_book3e(void);
+#endif
+
+static void clear_all_bpt(void);
+
+#ifdef CONFIG_PPC64
+#define REG		"%.16lx"
+#else
+#define REG		"%.8lx"
+#endif
+
+#ifdef __LITTLE_ENDIAN__
+#define GETWORD(v)	(((v)[3] << 24) + ((v)[2] << 16) + ((v)[1] << 8) + (v)[0])
+#else
+#define GETWORD(v)	(((v)[0] << 24) + ((v)[1] << 16) + ((v)[2] << 8) + (v)[3])
+#endif
+
+static const char *xmon_ro_msg = "Operation disabled: xmon in read-only mode\n";
+
+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\
+  c# $	run command '$' (one of 'r','S' or 't') on all cpus in xmon\n"
+#endif
+  "\
+  C	checksum\n\
+  d	dump bytes\n\
+  d1	dump 1 byte values\n\
+  d2	dump 2 byte values\n\
+  d4	dump 4 byte values\n\
+  d8	dump 8 byte values\n\
+  di	dump instructions\n\
+  df	dump float values\n\
+  dd	dump double values\n\
+  dl    dump the kernel log buffer\n"
+#ifdef CONFIG_PPC_POWERNV
+  "\
+  do    dump the OPAL message log\n"
+#endif
+#ifdef CONFIG_PPC64
+  "\
+  dp[#]	dump paca for current cpu, or cpu #\n\
+  dpa	dump paca for all possible cpus\n"
+#endif
+  "\
+  dr	dump stream of raw bytes\n\
+  dv	dump virtual address translation \n\
+  dt	dump the tracing buffers (uses printk)\n\
+  dtc	dump the tracing buffers for current CPU (uses printk)\n\
+"
+#ifdef CONFIG_PPC_POWERNV
+"  dx#   dump xive on CPU #\n\
+  dxi#  dump xive irq state #\n\
+  dxa   dump xive on all CPUs\n"
+#endif
+"  e	print exception information\n\
+  f	flush cache\n\
+  la	lookup symbol+offset of specified address\n\
+  ls	lookup address of specified symbol\n\
+  lp s [#]	lookup address of percpu symbol s for current cpu, or cpu #\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 	call a procedure\n\
+  P 	list processes/tasks\n\
+  r	print registers\n\
+  s	single step\n"
+#ifdef CONFIG_SPU_BASE
+"  ss	stop execution on all spus\n\
+  sr	restore execution on stopped spus\n\
+  sf  #	dump spu fields for spu # (in hex)\n\
+  sd  #	dump spu local store for spu # (in hex)\n\
+  sdi #	disassemble spu local store for spu # (in hex)\n"
+#endif
+"  S	print special registers\n\
+  Sa    print all SPRs\n\
+  Sr #	read SPR #\n\
+  Sw #v write v to SPR #\n\
+  t	print backtrace\n\
+  x	exit monitor and recover\n\
+  X	exit monitor and don't recover\n"
+#if defined(CONFIG_PPC_BOOK3S_64)
+"  u	dump segment table or SLB\n"
+#elif defined(CONFIG_PPC_BOOK3S_32)
+"  u	dump segment registers\n"
+#elif defined(CONFIG_44x) || defined(CONFIG_PPC_BOOK3E_64)
+"  u	dump TLB\n"
+#endif
+"  U	show uptime information\n"
+"  ?	help\n"
+"  # n	limit output to n lines per page (for dp, dpa, dl)\n"
+"  zr	reboot\n"
+"  zh	halt\n"
+;
+
+#ifdef CONFIG_SECURITY
+static bool xmon_is_locked_down(void)
+{
+	static bool lockdown;
+
+	if (!lockdown) {
+		lockdown = !!security_locked_down(LOCKDOWN_XMON_RW);
+		if (lockdown) {
+			printf("xmon: Disabled due to kernel lockdown\n");
+			xmon_is_ro = true;
+		}
+	}
+
+	if (!xmon_is_ro) {
+		xmon_is_ro = !!security_locked_down(LOCKDOWN_XMON_WR);
+		if (xmon_is_ro)
+			printf("xmon: Read-only due to kernel lockdown\n");
+	}
+
+	return lockdown;
+}
+#else /* CONFIG_SECURITY */
+static inline bool xmon_is_locked_down(void)
+{
+	return false;
+}
+#endif
+
+static struct pt_regs *xmon_regs;
+
+static inline void sync(void)
+{
+	asm volatile("sync; isync");
+}
+
+static inline void cflush(void *p)
+{
+	asm volatile ("dcbf 0,%0; icbi 0,%0" : : "r" (p));
+}
+
+static inline void cinval(void *p)
+{
+	asm volatile ("dcbi 0,%0; icbi 0,%0" : : "r" (p));
+}
+
+/**
+ * write_ciabr() - write the CIABR SPR
+ * @ciabr:	The value to write.
+ *
+ * This function writes a value to the CIARB register either directly
+ * through mtspr instruction if the kernel is in HV privilege mode or
+ * call a hypervisor function to achieve the same in case the kernel
+ * is in supervisor privilege mode.
+ */
+static void write_ciabr(unsigned long ciabr)
+{
+	if (!cpu_has_feature(CPU_FTR_ARCH_207S))
+		return;
+
+	if (cpu_has_feature(CPU_FTR_HVMODE)) {
+		mtspr(SPRN_CIABR, ciabr);
+		return;
+	}
+	plpar_set_ciabr(ciabr);
+}
+
+/**
+ * set_ciabr() - set the CIABR
+ * @addr:	The value to set.
+ *
+ * This function sets the correct privilege value into the HW
+ * breakpoint address before writing it up in the CIABR register.
+ */
+static void set_ciabr(unsigned long addr)
+{
+	addr &= ~CIABR_PRIV;
+
+	if (cpu_has_feature(CPU_FTR_HVMODE))
+		addr |= CIABR_PRIV_HYPER;
+	else
+		addr |= CIABR_PRIV_SUPER;
+	write_ciabr(addr);
+}
+
+/*
+ * 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.
+	 */
+	if (set_indicator_token == RTAS_UNKNOWN_SERVICE)
+		return;
+
+	rtas_call_unlocked(&args, set_indicator_token, 3, 1, NULL,
+			   SURVEILLANCE_TOKEN, 0, 0);
+
+#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 (;;) {
+		last_speaker = cmpxchg(&xmon_speaker, 0, me);
+		if (last_speaker == 0)
+			return;
+
+		/*
+		 * Wait a full second for the lock, we might be on a slow
+		 * console, but check every 100us.
+		 */
+		timeout = 10000;
+		while (xmon_speaker == last_speaker) {
+			if (--timeout > 0) {
+				udelay(100);
+				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;
+}
+
+int cpus_are_in_xmon(void)
+{
+	return !cpumask_empty(&cpus_in_xmon);
+}
+
+static bool wait_for_other_cpus(int ncpus)
+{
+	unsigned long timeout;
+
+	/* We wait for 2s, which is a metric "little while" */
+	for (timeout = 20000; timeout != 0; --timeout) {
+		if (cpumask_weight(&cpus_in_xmon) >= ncpus)
+			return true;
+		udelay(100);
+		barrier();
+	}
+
+	return false;
+}
+#else /* CONFIG_SMP */
+static inline void get_output_lock(void) {}
+static inline void release_output_lock(void) {}
+#endif
+
+static void xmon_touch_watchdogs(void)
+{
+	touch_softlockup_watchdog_sync();
+	rcu_cpu_stall_reset();
+	touch_nmi_watchdog();
+}
+
+static int xmon_core(struct pt_regs *regs, volatile int fromipi)
+{
+	volatile int cmd = 0;
+	struct bpt *volatile bp;
+	long recurse_jmp[JMP_BUF_LEN];
+	bool locked_down;
+	unsigned long offset;
+	unsigned long flags;
+#ifdef CONFIG_SMP
+	int cpu;
+	int secondary;
+#endif
+
+	local_irq_save(flags);
+	hard_irq_disable();
+
+	locked_down = xmon_is_locked_down();
+
+	if (!fromipi) {
+		tracing_enabled = tracing_is_on();
+		tracing_off();
+	}
+
+	bp = in_breakpoint_table(regs->nip, &offset);
+	if (bp != NULL) {
+		regs_set_return_ip(regs, bp->address + offset);
+		atomic_dec(&bp->ref_count);
+	}
+
+	remove_cpu_bpts();
+
+#ifdef CONFIG_SMP
+	cpu = smp_processor_id();
+	if (cpumask_test_cpu(cpu, &cpus_in_xmon)) {
+		/*
+		 * We catch SPR read/write faults here because the 0x700, 0xf60
+		 * etc. handlers don't call debugger_fault_handler().
+		 */
+		if (catch_spr_faults)
+			longjmp(bus_error_jmp, 1);
+		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)));
+		release_output_lock();
+		longjmp(xmon_fault_jmp[cpu], 1);
+	}
+
+	if (setjmp(recurse_jmp) != 0) {
+		if (!in_xmon || !xmon_gate) {
+			get_output_lock();
+			printf("xmon: WARNING: bad recursive fault "
+			       "on cpu 0x%x\n", cpu);
+			release_output_lock();
+			goto waiting;
+		}
+		secondary = !(xmon_taken && cpu == xmon_owner);
+		goto cmdloop;
+	}
+
+	xmon_fault_jmp[cpu] = recurse_jmp;
+
+	bp = NULL;
+	if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) == (MSR_IR|MSR_64BIT))
+		bp = at_breakpoint(regs->nip);
+	if (bp || regs_is_unrecoverable(regs))
+		fromipi = 0;
+
+	if (!fromipi) {
+		get_output_lock();
+		if (!locked_down)
+			excprint(regs);
+		if (bp) {
+			printf("cpu 0x%x stopped at breakpoint 0x%tx (",
+			       cpu, BP_NUM(bp));
+			xmon_print_symbol(regs->nip, " ", ")\n");
+		}
+		if (regs_is_unrecoverable(regs))
+			printf("WARNING: exception is not recoverable, "
+			       "can't continue\n");
+		release_output_lock();
+	}
+
+	cpumask_set_cpu(cpu, &cpus_in_xmon);
+
+ waiting:
+	secondary = 1;
+	spin_begin();
+	while (secondary && !xmon_gate) {
+		if (in_xmon == 0) {
+			if (fromipi) {
+				spin_end();
+				goto leave;
+			}
+			secondary = test_and_set_bit(0, &in_xmon);
+		}
+		spin_cpu_relax();
+		touch_nmi_watchdog();
+	}
+	spin_end();
+
+	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) {
+			/*
+			 * A system reset (trap == 0x100) can be triggered on
+			 * all CPUs, so when we come in via 0x100 try waiting
+			 * for the other CPUs to come in before we send the
+			 * debugger break (IPI). This is similar to
+			 * crash_kexec_secondary().
+			 */
+			if (TRAP(regs) !=  INTERRUPT_SYSTEM_RESET || !wait_for_other_cpus(ncpus))
+				smp_send_debugger_break();
+
+			wait_for_other_cpus(ncpus);
+		}
+		remove_bpts();
+		disable_surveillance();
+
+		if (!locked_down) {
+			/* for breakpoint or single step, print curr insn */
+			if (bp || TRAP(regs) == INTERRUPT_TRACE)
+				ppc_inst_dump(regs->nip, 1, 0);
+			printf("enter ? for help\n");
+		}
+
+		mb();
+		xmon_gate = 1;
+		barrier();
+		touch_nmi_watchdog();
+	}
+
+ cmdloop:
+	while (in_xmon) {
+		if (secondary) {
+			spin_begin();
+			if (cpu == xmon_owner) {
+				if (!test_and_set_bit(0, &xmon_taken)) {
+					secondary = 0;
+					spin_end();
+					continue;
+				}
+				/* missed it */
+				while (cpu == xmon_owner)
+					spin_cpu_relax();
+			}
+			spin_cpu_relax();
+			touch_nmi_watchdog();
+		} else {
+			cmd = 1;
+#ifdef CONFIG_SMP
+			if (xmon_batch)
+				cmd = batch_cmds(regs);
+#endif
+			if (!locked_down && cmd)
+				cmd = cmds(regs);
+			if (locked_down || cmd != 0) {
+				/* exiting xmon */
+				insert_bpts();
+				xmon_gate = 0;
+				wmb();
+				in_xmon = 0;
+				break;
+			}
+			/* have switched to some other cpu */
+			secondary = 1;
+		}
+	}
+ leave:
+	cpumask_clear_cpu(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 %tx (", BP_NUM(bp));
+			xmon_print_symbol(regs->nip, " ", ")\n");
+		}
+		if (regs_is_unrecoverable(regs))
+			printf("WARNING: exception is not recoverable, "
+			       "can't continue\n");
+		remove_bpts();
+		disable_surveillance();
+		if (!locked_down) {
+			/* for breakpoint or single step, print current insn */
+			if (bp || TRAP(regs) == INTERRUPT_TRACE)
+				ppc_inst_dump(regs->nip, 1, 0);
+			printf("enter ? for help\n");
+		}
+	}
+
+	if (!locked_down)
+		cmd = cmds(regs);
+
+	insert_bpts();
+	in_xmon = 0;
+#endif
+
+#ifdef CONFIG_BOOKE
+	if (regs->msr & MSR_DE) {
+		bp = at_breakpoint(regs->nip);
+		if (bp != NULL) {
+			regs_set_return_ip(regs, (unsigned long) &bp->instr[0]);
+			atomic_inc(&bp->ref_count);
+		}
+	}
+#else
+	if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) == (MSR_IR|MSR_64BIT)) {
+		bp = at_breakpoint(regs->nip);
+		if (bp != NULL) {
+			int stepped = emulate_step(regs, ppc_inst_read(bp->instr));
+			if (stepped == 0) {
+				regs_set_return_ip(regs, (unsigned long) &bp->instr[0]);
+				atomic_inc(&bp->ref_count);
+			} else if (stepped < 0) {
+				printf("Couldn't single-step %s instruction\n",
+				    IS_RFID(ppc_inst_read(bp->instr))? "rfid": "mtmsrd");
+			}
+		}
+	}
+#endif
+	if (locked_down)
+		clear_all_bpt();
+	else
+		insert_cpu_bpts();
+
+	xmon_touch_watchdogs();
+	local_irq_restore(flags);
+
+	return cmd != 'X' && cmd != EOF;
+}
+
+int xmon(struct pt_regs *excp)
+{
+	struct pt_regs regs;
+
+	if (excp == NULL) {
+		ppc_save_regs(&regs);
+		excp = &regs;
+	}
+
+	return xmon_core(excp, 0);
+}
+EXPORT_SYMBOL(xmon);
+
+irqreturn_t xmon_irq(int irq, void *d)
+{
+	unsigned long flags;
+	local_irq_save(flags);
+	printf("Keyboard interrupt\n");
+	xmon(get_irq_regs());
+	local_irq_restore(flags);
+	return IRQ_HANDLED;
+}
+
+static int xmon_bpt(struct pt_regs *regs)
+{
+	struct bpt *bp;
+	unsigned long offset;
+
+	if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) != (MSR_IR|MSR_64BIT))
+		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 || offset == 8)) {
+		regs_set_return_ip(regs, bp->address + offset);
+		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;
+}
+
+static int xmon_sstep(struct pt_regs *regs)
+{
+	if (user_mode(regs))
+		return 0;
+	xmon_core(regs, 0);
+	return 1;
+}
+
+static int xmon_break_match(struct pt_regs *regs)
+{
+	int i;
+
+	if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) != (MSR_IR|MSR_64BIT))
+		return 0;
+	for (i = 0; i < nr_wp_slots(); i++) {
+		if (dabr[i].enabled)
+			goto found;
+	}
+	return 0;
+
+found:
+	xmon_core(regs, 0);
+	return 1;
+}
+
+static int xmon_iabr_match(struct pt_regs *regs)
+{
+	if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) != (MSR_IR|MSR_64BIT))
+		return 0;
+	if (iabr == NULL)
+		return 0;
+	xmon_core(regs, 0);
+	return 1;
+}
+
+static int xmon_ipi(struct pt_regs *regs)
+{
+#ifdef CONFIG_SMP
+	if (in_xmon && !cpumask_test_cpu(smp_processor_id(), &cpus_in_xmon))
+		xmon_core(regs, 1);
+#endif
+	return 0;
+}
+
+static 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_64BIT)) == (MSR_IR|MSR_64BIT)) {
+		bp = in_breakpoint_table(regs->nip, &offset);
+		if (bp != NULL) {
+			regs_set_return_ip(regs, bp->address + offset);
+			atomic_dec(&bp->ref_count);
+		}
+	}
+
+	return 0;
+}
+
+/* Force enable xmon if not already enabled */
+static inline void force_enable_xmon(void)
+{
+	/* Enable xmon hooks if needed */
+	if (!xmon_on) {
+		printf("xmon: Enabling debugger hooks\n");
+		xmon_on = 1;
+	}
+}
+
+static struct bpt *at_breakpoint(unsigned long pc)
+{
+	int i;
+	struct bpt *volatile 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)bpt_table;
+	if (off >= sizeof(bpt_table))
+		return NULL;
+	*offp = off & (BPT_SIZE - 1);
+	if (off & 3)
+		return NULL;
+	return bpts + (off / BPT_SIZE);
+}
+
+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 = (void *)(bpt_table + ((bp - bpts) * BPT_WORDS));
+			return bp;
+		}
+	}
+
+	printf("Sorry, no free breakpoints.  Please clear one first.\n");
+	return NULL;
+}
+
+static void insert_bpts(void)
+{
+	int i;
+	ppc_inst_t instr, instr2;
+	struct bpt *bp, *bp2;
+
+	bp = bpts;
+	for (i = 0; i < NBPTS; ++i, ++bp) {
+		if ((bp->enabled & (BP_TRAP|BP_CIABR)) == 0)
+			continue;
+		if (!mread_instr(bp->address, &instr)) {
+			printf("Couldn't read instruction at %lx, "
+			       "disabling breakpoint there\n", bp->address);
+			bp->enabled = 0;
+			continue;
+		}
+		if (!can_single_step(ppc_inst_val(instr))) {
+			printf("Breakpoint at %lx is on an instruction that can't be single stepped, disabling it\n",
+					bp->address);
+			bp->enabled = 0;
+			continue;
+		}
+		/*
+		 * Check the address is not a suffix by looking for a prefix in
+		 * front of it.
+		 */
+		if (mread_instr(bp->address - 4, &instr2) == 8) {
+			printf("Breakpoint at %lx is on the second word of a prefixed instruction, disabling it\n",
+			       bp->address);
+			bp->enabled = 0;
+			continue;
+		}
+		/*
+		 * We might still be a suffix - if the prefix has already been
+		 * replaced by a breakpoint we won't catch it with the above
+		 * test.
+		 */
+		bp2 = at_breakpoint(bp->address - 4);
+		if (bp2 && ppc_inst_prefixed(ppc_inst_read(bp2->instr))) {
+			printf("Breakpoint at %lx is on the second word of a prefixed instruction, disabling it\n",
+			       bp->address);
+			bp->enabled = 0;
+			continue;
+		}
+
+		patch_instruction(bp->instr, instr);
+		patch_instruction(ppc_inst_next(bp->instr, bp->instr),
+				  ppc_inst(bpinstr));
+		if (bp->enabled & BP_CIABR)
+			continue;
+		if (patch_instruction((u32 *)bp->address,
+				      ppc_inst(bpinstr)) != 0) {
+			printf("Couldn't write instruction at %lx, "
+			       "disabling breakpoint there\n", bp->address);
+			bp->enabled &= ~BP_TRAP;
+			continue;
+		}
+	}
+}
+
+static void insert_cpu_bpts(void)
+{
+	int i;
+	struct arch_hw_breakpoint brk;
+
+	for (i = 0; i < nr_wp_slots(); i++) {
+		if (dabr[i].enabled) {
+			brk.address = dabr[i].address;
+			brk.type = (dabr[i].enabled & HW_BRK_TYPE_DABR) | HW_BRK_TYPE_PRIV_ALL;
+			brk.len = 8;
+			brk.hw_len = 8;
+			__set_breakpoint(i, &brk);
+		}
+	}
+
+	if (iabr)
+		set_ciabr(iabr->address);
+}
+
+static void remove_bpts(void)
+{
+	int i;
+	struct bpt *bp;
+	ppc_inst_t instr;
+
+	bp = bpts;
+	for (i = 0; i < NBPTS; ++i, ++bp) {
+		if ((bp->enabled & (BP_TRAP|BP_CIABR)) != BP_TRAP)
+			continue;
+		if (mread_instr(bp->address, &instr)
+		    && ppc_inst_equal(instr, ppc_inst(bpinstr))
+		    && patch_instruction(
+			(u32 *)bp->address, ppc_inst_read(bp->instr)) != 0)
+			printf("Couldn't remove breakpoint at %lx\n",
+			       bp->address);
+	}
+}
+
+static void remove_cpu_bpts(void)
+{
+	hw_breakpoint_disable();
+	write_ciabr(0);
+}
+
+/* Based on uptime_proc_show(). */
+static void
+show_uptime(void)
+{
+	struct timespec64 uptime;
+
+	if (setjmp(bus_error_jmp) == 0) {
+		catch_memory_errors = 1;
+		sync();
+
+		ktime_get_coarse_boottime_ts64(&uptime);
+		printf("Uptime: %lu.%.2lu seconds\n", (unsigned long)uptime.tv_sec,
+			((unsigned long)uptime.tv_nsec / (NSEC_PER_SEC/100)));
+
+		sync();
+		__delay(200);						\
+	}
+	catch_memory_errors = 0;
+}
+
+static void set_lpp_cmd(void)
+{
+	unsigned long lpp;
+
+	if (!scanhex(&lpp)) {
+		printf("Invalid number.\n");
+		lpp = 0;
+	}
+	xmon_set_pagination_lpp(lpp);
+}
+/* Command interpreting routine */
+static char *last_cmd;
+
+static int
+cmds(struct pt_regs *excp)
+{
+	int cmd = 0;
+
+	last_cmd = NULL;
+	xmon_regs = excp;
+
+	xmon_show_stack(excp->gpr[1], excp->link, excp->nip);
+
+	for(;;) {
+#ifdef CONFIG_SMP
+		printf("%x:", smp_processor_id());
+#endif /* CONFIG_SMP */
+		printf("mon> ");
+		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':
+				if (xmon_is_ro) {
+					printf(xmon_ro_msg);
+					break;
+				}
+				memzcan();
+				break;
+			case 'i':
+				show_mem(0, NULL);
+				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_spu_cmd() == 0)
+				break;
+			if (do_step(excp))
+				return cmd;
+			break;
+		case 'x':
+		case 'X':
+			if (tracing_enabled)
+				tracing_on();
+			return cmd;
+		case EOF:
+			printf(" <no input ...>\n");
+			mdelay(2000);
+			return cmd;
+		case '?':
+			xmon_puts(help_string);
+			break;
+		case '#':
+			set_lpp_cmd();
+			break;
+		case 'b':
+			bpt_cmds();
+			break;
+		case 'C':
+			csum();
+			break;
+		case 'c':
+			if (cpu_cmd())
+				return 0;
+			break;
+		case 'z':
+			bootcmds();
+			break;
+		case 'p':
+			if (xmon_is_ro) {
+				printf(xmon_ro_msg);
+				break;
+			}
+			proccall();
+			break;
+		case 'P':
+			show_tasks();
+			break;
+#if defined(CONFIG_PPC_BOOK3S_32) || defined(CONFIG_PPC_64S_HASH_MMU)
+		case 'u':
+			dump_segments();
+			break;
+#elif defined(CONFIG_44x)
+		case 'u':
+			dump_tlb_44x();
+			break;
+#elif defined(CONFIG_PPC_BOOK3E_64)
+		case 'u':
+			dump_tlb_book3e();
+			break;
+#endif
+		case 'U':
+			show_uptime();
+			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;
+		}
+	}
+}
+
+#ifdef CONFIG_BOOKE
+static int do_step(struct pt_regs *regs)
+{
+	regs_set_return_msr(regs, regs->msr | MSR_DE);
+	mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) | DBCR0_IC | DBCR0_IDM);
+	return 1;
+}
+#else
+/*
+ * Step a single instruction.
+ * Some instructions we emulate, others we execute with MSR_SE set.
+ */
+static int do_step(struct pt_regs *regs)
+{
+	ppc_inst_t instr;
+	int stepped;
+
+	force_enable_xmon();
+	/* check we are in 64-bit kernel mode, translation enabled */
+	if ((regs->msr & (MSR_64BIT|MSR_PR|MSR_IR)) == (MSR_64BIT|MSR_IR)) {
+		if (mread_instr(regs->nip, &instr)) {
+			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) {
+				set_trap(regs, 0xd00);
+				printf("stepped to ");
+				xmon_print_symbol(regs->nip, " ", "\n");
+				ppc_inst_dump(regs->nip, 1, 0);
+				return 0;
+			}
+		}
+	}
+	regs_set_return_msr(regs, regs->msr | MSR_SE);
+	return 1;
+}
+#endif
+
+static void bootcmds(void)
+{
+	char tmp[64];
+	int cmd;
+
+	cmd = inchar();
+	if (cmd == 'r') {
+		getstring(tmp, 64);
+		ppc_md.restart(tmp);
+	} else if (cmd == 'h') {
+		ppc_md.halt();
+	} else if (cmd == 'p') {
+		do_kernel_power_off();
+	}
+}
+
+#ifdef CONFIG_SMP
+static int xmon_switch_cpu(unsigned long cpu)
+{
+	int timeout;
+
+	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 0x%lx didn't take control\n", cpu);
+			return 0;
+		}
+		barrier();
+	}
+	return 1;
+}
+
+static int xmon_batch_next_cpu(void)
+{
+	unsigned long cpu;
+
+	while (!cpumask_empty(&xmon_batch_cpus)) {
+		cpu = cpumask_next_wrap(smp_processor_id(), &xmon_batch_cpus,
+					xmon_batch_start_cpu, true);
+		if (cpu == nr_cpumask_bits)
+			break;
+		if (xmon_batch_start_cpu == -1)
+			xmon_batch_start_cpu = cpu;
+		if (xmon_switch_cpu(cpu))
+			return 0;
+		cpumask_clear_cpu(cpu, &xmon_batch_cpus);
+	}
+
+	xmon_batch = 0;
+	printf("%x:mon> \n", smp_processor_id());
+	return 1;
+}
+
+static int batch_cmds(struct pt_regs *excp)
+{
+	int cmd;
+
+	/* simulate command entry */
+	cmd = xmon_batch;
+	termch = '\n';
+
+	last_cmd = NULL;
+	xmon_regs = excp;
+
+	printf("%x:", smp_processor_id());
+	printf("mon> ");
+	printf("%c\n", (char)cmd);
+
+	switch (cmd) {
+	case 'r':
+		prregs(excp);	/* print regs */
+		break;
+	case 'S':
+		super_regs();
+		break;
+	case 't':
+		backtrace(excp);
+		break;
+	}
+
+	cpumask_clear_cpu(smp_processor_id(), &xmon_batch_cpus);
+
+	return xmon_batch_next_cpu();
+}
+
+static int cpu_cmd(void)
+{
+	unsigned long cpu, first_cpu, last_cpu;
+
+	cpu = skipbl();
+	if (cpu == '#') {
+		xmon_batch = skipbl();
+		if (xmon_batch) {
+			switch (xmon_batch) {
+			case 'r':
+			case 'S':
+			case 't':
+				cpumask_copy(&xmon_batch_cpus, &cpus_in_xmon);
+				if (cpumask_weight(&xmon_batch_cpus) <= 1) {
+					printf("There are no other cpus in xmon\n");
+					break;
+				}
+				xmon_batch_start_cpu = -1;
+				if (!xmon_batch_next_cpu())
+					return 1;
+				break;
+			default:
+				printf("c# only supports 'r', 'S' and 't' commands\n");
+			}
+			xmon_batch = 0;
+			return 0;
+		}
+	}
+	termch = cpu;
+
+	if (!scanhex(&cpu)) {
+		/* print cpus waiting or in xmon */
+		printf("cpus stopped:");
+		last_cpu = first_cpu = NR_CPUS;
+		for_each_possible_cpu(cpu) {
+			if (cpumask_test_cpu(cpu, &cpus_in_xmon)) {
+				if (cpu == last_cpu + 1) {
+					last_cpu = cpu;
+				} else {
+					if (last_cpu != first_cpu)
+						printf("-0x%lx", last_cpu);
+					last_cpu = first_cpu = cpu;
+					printf(" 0x%lx", cpu);
+				}
+			}
+		}
+		if (last_cpu != first_cpu)
+			printf("-0x%lx", last_cpu);
+		printf("\n");
+		return 0;
+	}
+	/* try to switch to cpu specified */
+	if (!cpumask_test_cpu(cpu, &cpus_in_xmon)) {
+		printf("cpu 0x%lx isn't in xmon\n", cpu);
+#ifdef CONFIG_PPC64
+		printf("backtrace of paca[0x%lx].saved_r1 (possibly stale):\n", cpu);
+		xmon_show_stack(paca_ptrs[cpu]->saved_r1, 0, 0);
+#endif
+		return 0;
+	}
+
+	return xmon_switch_cpu(cpu);
+}
+#else
+static int cpu_cmd(void)
+{
+	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 "REG"\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)
+{
+	ppc_inst_t instr;
+
+	addr &= ~3;
+	if (!is_kernel_addr(addr)) {
+		printf("Breakpoints may only be placed at kernel addresses\n");
+		return 0;
+	}
+	if (!mread_instr(addr, &instr)) {
+		printf("Can't read instruction at address %lx\n", addr);
+		return 0;
+	}
+	if (!can_single_step(ppc_inst_val(instr))) {
+		printf("Breakpoints may not be placed on instructions that can't be single stepped\n");
+		return 0;
+	}
+	return 1;
+}
+
+static int find_free_data_bpt(void)
+{
+	int i;
+
+	for (i = 0; i < nr_wp_slots(); i++) {
+		if (!dabr[i].enabled)
+			return i;
+	}
+	printf("Couldn't find free breakpoint register\n");
+	return -1;
+}
+
+static void print_data_bpts(void)
+{
+	int i;
+
+	for (i = 0; i < nr_wp_slots(); i++) {
+		if (!dabr[i].enabled)
+			continue;
+
+		printf("   data   "REG"  [", dabr[i].address);
+		if (dabr[i].enabled & 1)
+			printf("r");
+		if (dabr[i].enabled & 2)
+			printf("w");
+		printf("]\n");
+	}
+}
+
+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 (POWER8 only)\n"
+    "bd <addr> [cnt]  set hardware data breakpoint\n"
+    "";
+
+static void
+bpt_cmds(void)
+{
+	int cmd;
+	unsigned long a;
+	int i;
+	struct bpt *bp;
+
+	cmd = inchar();
+
+	switch (cmd) {
+	case 'd': {	/* bd - hardware data breakpoint */
+		static const char badaddr[] = "Only kernel addresses are permitted for breakpoints\n";
+		int mode;
+		if (xmon_is_ro) {
+			printf(xmon_ro_msg);
+			break;
+		}
+		if (!ppc_breakpoint_available()) {
+			printf("Hardware data breakpoint not supported on this cpu\n");
+			break;
+		}
+		i = find_free_data_bpt();
+		if (i < 0)
+			break;
+		mode = 7;
+		cmd = inchar();
+		if (cmd == 'r')
+			mode = 5;
+		else if (cmd == 'w')
+			mode = 6;
+		else
+			termch = cmd;
+		dabr[i].address = 0;
+		dabr[i].enabled = 0;
+		if (scanhex(&dabr[i].address)) {
+			if (!is_kernel_addr(dabr[i].address)) {
+				printf(badaddr);
+				break;
+			}
+			dabr[i].address &= ~HW_BRK_TYPE_DABR;
+			dabr[i].enabled = mode | BP_DABR;
+		}
+
+		force_enable_xmon();
+		break;
+	}
+
+	case 'i':	/* bi - hardware instr breakpoint */
+		if (xmon_is_ro) {
+			printf(xmon_ro_msg);
+			break;
+		}
+		if (!cpu_has_feature(CPU_FTR_ARCH_207S)) {
+			printf("Hardware instruction breakpoint "
+			       "not supported on this cpu\n");
+			break;
+		}
+		if (iabr) {
+			iabr->enabled &= ~BP_CIABR;
+			iabr = NULL;
+		}
+		if (!scanhex(&a))
+			break;
+		if (!check_bp_loc(a))
+			break;
+		bp = new_breakpoint(a);
+		if (bp != NULL) {
+			bp->enabled |= BP_CIABR;
+			iabr = bp;
+			force_enable_xmon();
+		}
+		break;
+
+	case 'c':
+		if (!scanhex(&a)) {
+			/* clear all breakpoints */
+			for (i = 0; i < NBPTS; ++i)
+				bpts[i].enabled = 0;
+			iabr = NULL;
+			for (i = 0; i < nr_wp_slots(); i++)
+				dabr[i].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 == NULL) {
+				printf("No breakpoint at %lx\n", a);
+				break;
+			}
+		}
+
+		printf("Cleared breakpoint %tx (", 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 (xmon_is_ro || !scanhex(&a)) {
+			/* print all breakpoints */
+			printf("   type            address\n");
+			print_data_bpts();
+			for (bp = bpts; bp < &bpts[NBPTS]; ++bp) {
+				if (!bp->enabled)
+					continue;
+				printf("%tx %s   ", BP_NUM(bp),
+				    (bp->enabled & BP_CIABR) ? "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;
+			force_enable_xmon();
+		}
+		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:
+		if (radix_enabled())
+			ret = "(Data Access Out of Range)";
+		else
+			ret = "(Data SLB Access)";
+		break;
+	case 0x400:	ret = "(Instruction Access)"; break;
+	case 0x480:
+		if (radix_enabled())
+			ret = "(Instruction Access Out of Range)";
+		else
+			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 0x980:	ret = "(Hypervisor Decrementer)"; break;
+	case 0xa00:	ret = "(Doorbell)"; break;
+	case 0xc00:	ret = "(System Call)"; break;
+	case 0xd00:	ret = "(Single Step)"; break;
+	case 0xe40:	ret = "(Emulation Assist)"; break;
+	case 0xe60:	ret = "(HMI)"; break;
+	case 0xe80:	ret = "(Hypervisor Doorbell)"; break;
+	case 0xf00:	ret = "(Performance Monitor)"; break;
+	case 0xf20:	ret = "(Altivec Unavailable)"; break;
+	case 0x1300:	ret = "(Instruction Breakpoint)"; break;
+	case 0x1500:	ret = "(Denormalisation)"; break;
+	case 0x1700:	ret = "(Altivec Assist)"; break;
+	case 0x3000:	ret = "(System Call Vectored)"; 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;
+
+	*startp = *endp = 0;
+	if (pc == 0)
+		return;
+	if (setjmp(bus_error_jmp) == 0) {
+		catch_memory_errors = 1;
+		sync();
+		name = kallsyms_lookup(pc, &size, &offset, NULL, tmpstr);
+		if (name != NULL) {
+			*startp = pc - offset;
+			*endp = pc - offset + size;
+		}
+		sync();
+	}
+	catch_memory_errors = 0;
+}
+
+#define LRSAVE_OFFSET		(STACK_FRAME_LR_SAVE * sizeof(unsigned long))
+#define MARKER_OFFSET		(STACK_FRAME_MARKER * sizeof(unsigned long))
+
+static void xmon_show_stack(unsigned long sp, unsigned long lr,
+			    unsigned long pc)
+{
+	int max_to_print = 64;
+	unsigned long ip;
+	unsigned long newsp;
+	unsigned long marker;
+	struct pt_regs regs;
+
+	while (max_to_print--) {
+		if (!is_kernel_addr(sp)) {
+			if (sp != 0)
+				printf("SP (%lx) is in userspace\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 (!is_kernel_addr(lr)
+				    || (fnstart <= lr && lr < fnend))
+					printip = 0;
+			} else if (lr == nextip) {
+				printip = 0;
+			} else if (is_kernel_addr(lr)
+				   && !(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 == STACK_FRAME_REGS_MARKER) {
+			if (mread(sp + STACK_FRAME_OVERHEAD, &regs, sizeof(regs))
+			    != sizeof(regs)) {
+				printf("Couldn't read registers at %lx\n",
+				       sp + STACK_FRAME_OVERHEAD);
+				break;
+			}
+			printf("--- Exception: %lx %s at ", regs.trap,
+			       getvecname(TRAP(&regs)));
+			pc = regs.nip;
+			lr = regs.link;
+			xmon_print_symbol(pc, " ", "\n");
+		}
+
+		if (newsp == 0)
+			break;
+
+		sp = newsp;
+	}
+}
+
+static void backtrace(struct pt_regs *excp)
+{
+	unsigned long sp;
+
+	if (scanhex(&sp))
+		xmon_show_stack(sp, 0, 0);
+	else
+		xmon_show_stack(excp->gpr[1], excp->link, excp->nip);
+	scannl();
+}
+
+static void print_bug_trap(struct pt_regs *regs)
+{
+#ifdef CONFIG_BUG
+	const struct bug_entry *bug;
+	unsigned long addr;
+
+	if (regs->msr & MSR_PR)
+		return;		/* not in kernel */
+	addr = regs->nip;	/* address of trap instruction */
+	if (!is_kernel_addr(addr))
+		return;
+	bug = find_bug(regs->nip);
+	if (bug == NULL)
+		return;
+	if (is_warning_bug(bug))
+		return;
+
+#ifdef CONFIG_DEBUG_BUGVERBOSE
+	printf("kernel BUG at %s:%u!\n",
+	       (char *)bug + bug->file_disp, bug->line);
+#else
+	printf("kernel BUG at %px!\n", (void *)bug + bug->bug_addr_disp);
+#endif
+#endif /* CONFIG_BUG */
+}
+
+static void excprint(struct pt_regs *fp)
+{
+	unsigned long trap;
+
+#ifdef CONFIG_SMP
+	printf("cpu 0x%x: ", smp_processor_id());
+#endif /* CONFIG_SMP */
+
+	trap = TRAP(fp);
+	printf("Vector: %lx %s at [%px]\n", fp->trap, getvecname(trap), fp);
+	printf("    pc: ");
+	xmon_print_symbol(fp->nip, ": ", "\n");
+
+	printf("    lr: ");
+	xmon_print_symbol(fp->link, ": ", "\n");
+
+	printf("    sp: %lx\n", fp->gpr[1]);
+	printf("   msr: %lx\n", fp->msr);
+
+	if (trap == INTERRUPT_DATA_STORAGE ||
+	    trap == INTERRUPT_DATA_SEGMENT ||
+	    trap == INTERRUPT_ALIGNMENT ||
+	    trap == INTERRUPT_MACHINE_CHECK) {
+		printf("   dar: %lx\n", fp->dar);
+		if (trap != INTERRUPT_DATA_SEGMENT)
+			printf(" dsisr: %lx\n", fp->dsisr);
+	}
+
+	printf("  current = 0x%px\n", current);
+#ifdef CONFIG_PPC64
+	printf("  paca    = 0x%px\t irqmask: 0x%02x\t irq_happened: 0x%02x\n",
+	       local_paca, local_paca->irq_soft_mask, local_paca->irq_happened);
+#endif
+	if (current) {
+		printf("    pid   = %d, comm = %s\n",
+		       current->pid, current->comm);
+	}
+
+	if (trap == INTERRUPT_PROGRAM)
+		print_bug_trap(fp);
+
+	printf(linux_banner);
+}
+
+static void prregs(struct pt_regs *fp)
+{
+	int n, trap;
+	unsigned long base;
+	struct pt_regs regs;
+
+	if (scanhex(&base)) {
+		if (setjmp(bus_error_jmp) == 0) {
+			catch_memory_errors = 1;
+			sync();
+			regs = *(struct pt_regs *)base;
+			sync();
+			__delay(200);
+		} else {
+			catch_memory_errors = 0;
+			printf("*** Error reading registers from "REG"\n",
+			       base);
+			return;
+		}
+		catch_memory_errors = 0;
+		fp = &regs;
+	}
+
+#ifdef CONFIG_PPC64
+#define R_PER_LINE 2
+#else
+#define R_PER_LINE 4
+#endif
+
+	for (n = 0; n < 32; ++n) {
+		printf("R%.2d = "REG"%s", n, fp->gpr[n],
+			(n % R_PER_LINE) == R_PER_LINE - 1 ? "\n" : "   ");
+	}
+
+	printf("pc  = ");
+	xmon_print_symbol(fp->nip, " ", "\n");
+	if (!trap_is_syscall(fp) && cpu_has_feature(CPU_FTR_CFAR)) {
+		printf("cfar= ");
+		xmon_print_symbol(fp->orig_gpr3, " ", "\n");
+	}
+	printf("lr  = ");
+	xmon_print_symbol(fp->link, " ", "\n");
+	printf("msr = "REG"   cr  = %.8lx\n", fp->msr, fp->ccr);
+	printf("ctr = "REG"   xer = "REG"   trap = %4lx\n",
+	       fp->ctr, fp->xer, fp->trap);
+	trap = TRAP(fp);
+	if (trap == INTERRUPT_DATA_STORAGE ||
+	    trap == INTERRUPT_DATA_SEGMENT ||
+	    trap == INTERRUPT_ALIGNMENT)
+		printf("dar = "REG"   dsisr = %.8lx\n", fp->dar, fp->dsisr);
+}
+
+static void cacheflush(void)
+{
+	int cmd;
+	unsigned long nflush;
+
+	cmd = inchar();
+	if (cmd != 'i')
+		termch = cmd;
+	scanhex((void *)&adrs);
+	if (termch != '\n')
+		termch = 0;
+	nflush = 1;
+	scanhex(&nflush);
+	nflush = (nflush + L1_CACHE_BYTES - 1) / L1_CACHE_BYTES;
+	if (setjmp(bus_error_jmp) == 0) {
+		catch_memory_errors = 1;
+		sync();
+
+		if (cmd != 'i' || IS_ENABLED(CONFIG_PPC_BOOK3S_64)) {
+			for (; nflush > 0; --nflush, adrs += L1_CACHE_BYTES)
+				cflush((void *) adrs);
+		} else {
+			for (; nflush > 0; --nflush, adrs += L1_CACHE_BYTES)
+				cinval((void *) adrs);
+		}
+		sync();
+		/* wait a little while to see if we get a machine check */
+		__delay(200);
+	}
+	catch_memory_errors = 0;
+}
+
+extern unsigned long xmon_mfspr(int spr, unsigned long default_value);
+extern void xmon_mtspr(int spr, unsigned long value);
+
+static int
+read_spr(int n, unsigned long *vp)
+{
+	unsigned long ret = -1UL;
+	int ok = 0;
+
+	if (setjmp(bus_error_jmp) == 0) {
+		catch_spr_faults = 1;
+		sync();
+
+		ret = xmon_mfspr(n, *vp);
+
+		sync();
+		*vp = ret;
+		ok = 1;
+	}
+	catch_spr_faults = 0;
+
+	return ok;
+}
+
+static void
+write_spr(int n, unsigned long val)
+{
+	if (xmon_is_ro) {
+		printf(xmon_ro_msg);
+		return;
+	}
+
+	if (setjmp(bus_error_jmp) == 0) {
+		catch_spr_faults = 1;
+		sync();
+
+		xmon_mtspr(n, val);
+
+		sync();
+	} else {
+		printf("SPR 0x%03x (%4d) Faulted during write\n", n, n);
+	}
+	catch_spr_faults = 0;
+}
+
+static void dump_206_sprs(void)
+{
+#ifdef CONFIG_PPC64
+	if (!cpu_has_feature(CPU_FTR_ARCH_206))
+		return;
+
+	/* Actually some of these pre-date 2.06, but whatever */
+
+	printf("srr0   = %.16lx  srr1  = %.16lx dsisr  = %.8lx\n",
+		mfspr(SPRN_SRR0), mfspr(SPRN_SRR1), mfspr(SPRN_DSISR));
+	printf("dscr   = %.16lx  ppr   = %.16lx pir    = %.8lx\n",
+		mfspr(SPRN_DSCR), mfspr(SPRN_PPR), mfspr(SPRN_PIR));
+	printf("amr    = %.16lx  uamor = %.16lx\n",
+		mfspr(SPRN_AMR), mfspr(SPRN_UAMOR));
+
+	if (!(mfmsr() & MSR_HV))
+		return;
+
+	printf("sdr1   = %.16lx  hdar  = %.16lx hdsisr = %.8lx\n",
+		mfspr(SPRN_SDR1), mfspr(SPRN_HDAR), mfspr(SPRN_HDSISR));
+	printf("hsrr0  = %.16lx hsrr1  = %.16lx hdec   = %.16lx\n",
+		mfspr(SPRN_HSRR0), mfspr(SPRN_HSRR1), mfspr(SPRN_HDEC));
+	printf("lpcr   = %.16lx  pcr   = %.16lx lpidr  = %.8lx\n",
+		mfspr(SPRN_LPCR), mfspr(SPRN_PCR), mfspr(SPRN_LPID));
+	printf("hsprg0 = %.16lx hsprg1 = %.16lx amor   = %.16lx\n",
+		mfspr(SPRN_HSPRG0), mfspr(SPRN_HSPRG1), mfspr(SPRN_AMOR));
+	printf("dabr   = %.16lx dabrx  = %.16lx\n",
+		mfspr(SPRN_DABR), mfspr(SPRN_DABRX));
+#endif
+}
+
+static void dump_207_sprs(void)
+{
+#ifdef CONFIG_PPC64
+	unsigned long msr;
+
+	if (!cpu_has_feature(CPU_FTR_ARCH_207S))
+		return;
+
+	printf("dpdes  = %.16lx  tir   = %.16lx cir    = %.8lx\n",
+		mfspr(SPRN_DPDES), mfspr(SPRN_TIR), mfspr(SPRN_CIR));
+
+	printf("fscr   = %.16lx  tar   = %.16lx pspb   = %.8lx\n",
+		mfspr(SPRN_FSCR), mfspr(SPRN_TAR), mfspr(SPRN_PSPB));
+
+	msr = mfmsr();
+	if (msr & MSR_TM) {
+		/* Only if TM has been enabled in the kernel */
+		printf("tfhar  = %.16lx  tfiar = %.16lx texasr = %.16lx\n",
+			mfspr(SPRN_TFHAR), mfspr(SPRN_TFIAR),
+			mfspr(SPRN_TEXASR));
+	}
+
+	printf("mmcr0  = %.16lx  mmcr1 = %.16lx mmcr2  = %.16lx\n",
+		mfspr(SPRN_MMCR0), mfspr(SPRN_MMCR1), mfspr(SPRN_MMCR2));
+	printf("pmc1   = %.8lx pmc2 = %.8lx  pmc3 = %.8lx  pmc4   = %.8lx\n",
+		mfspr(SPRN_PMC1), mfspr(SPRN_PMC2),
+		mfspr(SPRN_PMC3), mfspr(SPRN_PMC4));
+	printf("mmcra  = %.16lx   siar = %.16lx pmc5   = %.8lx\n",
+		mfspr(SPRN_MMCRA), mfspr(SPRN_SIAR), mfspr(SPRN_PMC5));
+	printf("sdar   = %.16lx   sier = %.16lx pmc6   = %.8lx\n",
+		mfspr(SPRN_SDAR), mfspr(SPRN_SIER), mfspr(SPRN_PMC6));
+	printf("ebbhr  = %.16lx  ebbrr = %.16lx bescr  = %.16lx\n",
+		mfspr(SPRN_EBBHR), mfspr(SPRN_EBBRR), mfspr(SPRN_BESCR));
+	printf("iamr   = %.16lx\n", mfspr(SPRN_IAMR));
+
+	if (!(msr & MSR_HV))
+		return;
+
+	printf("hfscr  = %.16lx  dhdes = %.16lx rpr    = %.16lx\n",
+		mfspr(SPRN_HFSCR), mfspr(SPRN_DHDES), mfspr(SPRN_RPR));
+	printf("dawr0  = %.16lx dawrx0 = %.16lx\n",
+	       mfspr(SPRN_DAWR0), mfspr(SPRN_DAWRX0));
+	if (nr_wp_slots() > 1) {
+		printf("dawr1  = %.16lx dawrx1 = %.16lx\n",
+		       mfspr(SPRN_DAWR1), mfspr(SPRN_DAWRX1));
+	}
+	printf("ciabr  = %.16lx\n", mfspr(SPRN_CIABR));
+#endif
+}
+
+static void dump_300_sprs(void)
+{
+#ifdef CONFIG_PPC64
+	bool hv = mfmsr() & MSR_HV;
+
+	if (!cpu_has_feature(CPU_FTR_ARCH_300))
+		return;
+
+	if (cpu_has_feature(CPU_FTR_P9_TIDR)) {
+		printf("pidr   = %.16lx  tidr  = %.16lx\n",
+			mfspr(SPRN_PID), mfspr(SPRN_TIDR));
+	} else {
+		printf("pidr   = %.16lx\n",
+			mfspr(SPRN_PID));
+	}
+
+	printf("psscr  = %.16lx\n",
+		hv ? mfspr(SPRN_PSSCR) : mfspr(SPRN_PSSCR_PR));
+
+	if (!hv)
+		return;
+
+	printf("ptcr   = %.16lx  asdr  = %.16lx\n",
+		mfspr(SPRN_PTCR), mfspr(SPRN_ASDR));
+#endif
+}
+
+static void dump_310_sprs(void)
+{
+#ifdef CONFIG_PPC64
+	if (!cpu_has_feature(CPU_FTR_ARCH_31))
+		return;
+
+	printf("mmcr3  = %.16lx, sier2  = %.16lx, sier3  = %.16lx\n",
+		mfspr(SPRN_MMCR3), mfspr(SPRN_SIER2), mfspr(SPRN_SIER3));
+
+#endif
+}
+
+static void dump_one_spr(int spr, bool show_unimplemented)
+{
+	unsigned long val;
+
+	val = 0xdeadbeef;
+	if (!read_spr(spr, &val)) {
+		printf("SPR 0x%03x (%4d) Faulted during read\n", spr, spr);
+		return;
+	}
+
+	if (val == 0xdeadbeef) {
+		/* Looks like read was a nop, confirm */
+		val = 0x0badcafe;
+		if (!read_spr(spr, &val)) {
+			printf("SPR 0x%03x (%4d) Faulted during read\n", spr, spr);
+			return;
+		}
+
+		if (val == 0x0badcafe) {
+			if (show_unimplemented)
+				printf("SPR 0x%03x (%4d) Unimplemented\n", spr, spr);
+			return;
+		}
+	}
+
+	printf("SPR 0x%03x (%4d) = 0x%lx\n", spr, spr, val);
+}
+
+static void super_regs(void)
+{
+	static unsigned long regno;
+	int cmd;
+	int spr;
+
+	cmd = skipbl();
+
+	switch (cmd) {
+	case '\n': {
+		unsigned long sp, toc;
+		asm("mr %0,1" : "=r" (sp) :);
+		asm("mr %0,2" : "=r" (toc) :);
+
+		printf("msr    = "REG"  sprg0 = "REG"\n",
+		       mfmsr(), mfspr(SPRN_SPRG0));
+		printf("pvr    = "REG"  sprg1 = "REG"\n",
+		       mfspr(SPRN_PVR), mfspr(SPRN_SPRG1));
+		printf("dec    = "REG"  sprg2 = "REG"\n",
+		       mfspr(SPRN_DEC), mfspr(SPRN_SPRG2));
+		printf("sp     = "REG"  sprg3 = "REG"\n", sp, mfspr(SPRN_SPRG3));
+		printf("toc    = "REG"  dar   = "REG"\n", toc, mfspr(SPRN_DAR));
+
+		dump_206_sprs();
+		dump_207_sprs();
+		dump_300_sprs();
+		dump_310_sprs();
+
+		return;
+	}
+	case 'w': {
+		unsigned long val;
+		scanhex(&regno);
+		val = 0;
+		read_spr(regno, &val);
+		scanhex(&val);
+		write_spr(regno, val);
+		dump_one_spr(regno, true);
+		break;
+	}
+	case 'r':
+		scanhex(&regno);
+		dump_one_spr(regno, true);
+		break;
+	case 'a':
+		/* dump ALL SPRs */
+		for (spr = 1; spr < 1024; ++spr)
+			dump_one_spr(spr, false);
+		break;
+	}
+
+	scannl();
+}
+
+/*
+ * Stuff for reading and writing memory safely
+ */
+static int
+mread(unsigned long adrs, void *buf, int size)
+{
+	volatile int n;
+	char *p, *q;
+
+	n = 0;
+	if (setjmp(bus_error_jmp) == 0) {
+		catch_memory_errors = 1;
+		sync();
+		p = (char *)adrs;
+		q = (char *)buf;
+		switch (size) {
+		case 2:
+			*(u16 *)q = *(u16 *)p;
+			break;
+		case 4:
+			*(u32 *)q = *(u32 *)p;
+			break;
+		case 8:
+			*(u64 *)q = *(u64 *)p;
+			break;
+		default:
+			for( ; n < size; ++n) {
+				*q++ = *p++;
+				sync();
+			}
+		}
+		sync();
+		/* wait a little while to see if we get a machine check */
+		__delay(200);
+		n = size;
+	}
+	catch_memory_errors = 0;
+	return n;
+}
+
+static int
+mwrite(unsigned long adrs, void *buf, int size)
+{
+	volatile int n;
+	char *p, *q;
+
+	n = 0;
+
+	if (xmon_is_ro) {
+		printf(xmon_ro_msg);
+		return n;
+	}
+
+	if (setjmp(bus_error_jmp) == 0) {
+		catch_memory_errors = 1;
+		sync();
+		p = (char *) adrs;
+		q = (char *) buf;
+		switch (size) {
+		case 2:
+			*(u16 *)p = *(u16 *)q;
+			break;
+		case 4:
+			*(u32 *)p = *(u32 *)q;
+			break;
+		case 8:
+			*(u64 *)p = *(u64 *)q;
+			break;
+		default:
+			for ( ; n < size; ++n) {
+				*p++ = *q++;
+				sync();
+			}
+		}
+		sync();
+		/* wait a little while to see if we get a machine check */
+		__delay(200);
+		n = size;
+	} else {
+		printf("*** Error writing address "REG"\n", adrs + n);
+	}
+	catch_memory_errors = 0;
+	return n;
+}
+
+static int
+mread_instr(unsigned long adrs, ppc_inst_t *instr)
+{
+	volatile int n;
+
+	n = 0;
+	if (setjmp(bus_error_jmp) == 0) {
+		catch_memory_errors = 1;
+		sync();
+		*instr = ppc_inst_read((u32 *)adrs);
+		sync();
+		/* wait a little while to see if we get a machine check */
+		__delay(200);
+		n = ppc_inst_len(*instr);
+	}
+	catch_memory_errors = 0;
+	return n;
+}
+
+static int fault_type;
+static int fault_except;
+static char *fault_chars[] = { "--", "**", "##" };
+
+static int handle_fault(struct pt_regs *regs)
+{
+	fault_except = TRAP(regs);
+	switch (TRAP(regs)) {
+	case 0x200:
+		fault_type = 0;
+		break;
+	case 0x300:
+	case 0x380:
+		fault_type = 1;
+		break;
+	default:
+		fault_type = 2;
+	}
+
+	longjmp(bus_error_jmp, 1);
+
+	return 0;
+}
+
+#define SWAP(a, b, t)	((t) = (a), (a) = (b), (b) = (t))
+
+static void
+byterev(unsigned char *val, int size)
+{
+	int t;
+	
+	switch (size) {
+	case 2:
+		SWAP(val[0], val[1], t);
+		break;
+	case 4:
+		SWAP(val[0], val[3], t);
+		SWAP(val[1], val[2], t);
+		break;
+	case 8: /* is there really any use for this? */
+		SWAP(val[0], val[7], t);
+		SWAP(val[1], val[6], t);
+		SWAP(val[2], val[5], t);
+		SWAP(val[3], val[4], t);
+		break;
+	}
+}
+
+static int brev;
+static int mnoread;
+
+static char *memex_help_string =
+    "Memory examine command usage:\n"
+    "m [addr] [flags] examine/change memory\n"
+    "  addr is optional.  will start where left off.\n"
+    "  flags may include chars from this set:\n"
+    "    b   modify by bytes (default)\n"
+    "    w   modify by words (2 byte)\n"
+    "    l   modify by longs (4 byte)\n"
+    "    d   modify by doubleword (8 byte)\n"
+    "    r   toggle reverse byte order mode\n"
+    "    n   do not read memory (for i/o spaces)\n"
+    "    .   ok to read (default)\n"
+    "NOTE: flags are saved as defaults\n"
+    "";
+
+static char *memex_subcmd_help_string =
+    "Memory examine subcommands:\n"
+    "  hexval   write this val to current location\n"
+    "  'string' write chars from string to this location\n"
+    "  '        increment address\n"
+    "  ^        decrement address\n"
+    "  /        increment addr by 0x10.  //=0x100, ///=0x1000, etc\n"
+    "  \\        decrement addr by 0x10.  \\\\=0x100, \\\\\\=0x1000, etc\n"
+    "  `        clear no-read flag\n"
+    "  ;        stay at this addr\n"
+    "  v        change to byte mode\n"
+    "  w        change to word (2 byte) mode\n"
+    "  l        change to long (4 byte) mode\n"
+    "  u        change to doubleword (8 byte) mode\n"
+    "  m addr   change current addr\n"
+    "  n        toggle no-read flag\n"
+    "  r        toggle byte reverse flag\n"
+    "  < count  back up count bytes\n"
+    "  > count  skip forward count bytes\n"
+    "  x        exit this mode\n"
+    "";
+
+static void
+memex(void)
+{
+	int cmd, inc, i, nslash;
+	unsigned long n;
+	unsigned char val[16];
+
+	scanhex((void *)&adrs);
+	cmd = skipbl();
+	if (cmd == '?') {
+		printf(memex_help_string);
+		return;
+	} else {
+		termch = cmd;
+	}
+	last_cmd = "m\n";
+	while ((cmd = skipbl()) != '\n') {
+		switch( cmd ){
+		case 'b':	size = 1;	break;
+		case 'w':	size = 2;	break;
+		case 'l':	size = 4;	break;
+		case 'd':	size = 8;	break;
+		case 'r': 	brev = !brev;	break;
+		case 'n':	mnoread = 1;	break;
+		case '.':	mnoread = 0;	break;
+		}
+	}
+	if( size <= 0 )
+		size = 1;
+	else if( size > 8 )
+		size = 8;
+	for(;;){
+		if (!mnoread)
+			n = mread(adrs, val, size);
+		printf(REG"%c", adrs, brev? 'r': ' ');
+		if (!mnoread) {
+			if (brev)
+				byterev(val, size);
+			putchar(' ');
+			for (i = 0; i < n; ++i)
+				printf("%.2x", val[i]);
+			for (; i < size; ++i)
+				printf("%s", fault_chars[fault_type]);
+		}
+		putchar(' ');
+		inc = size;
+		nslash = 0;
+		for(;;){
+			if( scanhex(&n) ){
+				for (i = 0; i < size; ++i)
+					val[i] = n >> (i * 8);
+				if (!brev)
+					byterev(val, size);
+				mwrite(adrs, val, size);
+				inc = size;
+			}
+			cmd = skipbl();
+			if (cmd == '\n')
+				break;
+			inc = 0;
+			switch (cmd) {
+			case '\'':
+				for(;;){
+					n = inchar();
+					if( n == '\\' )
+						n = bsesc();
+					else if( n == '\'' )
+						break;
+					for (i = 0; i < size; ++i)
+						val[i] = n >> (i * 8);
+					if (!brev)
+						byterev(val, size);
+					mwrite(adrs, val, size);
+					adrs += size;
+				}
+				adrs -= size;
+				inc = size;
+				break;
+			case ',':
+				adrs += size;
+				break;
+			case '.':
+				mnoread = 0;
+				break;
+			case ';':
+				break;
+			case 'x':
+			case EOF:
+				scannl();
+				return;
+			case 'b':
+			case 'v':
+				size = 1;
+				break;
+			case 'w':
+				size = 2;
+				break;
+			case 'l':
+				size = 4;
+				break;
+			case 'u':
+				size = 8;
+				break;
+			case '^':
+				adrs -= size;
+				break;
+			case '/':
+				if (nslash > 0)
+					adrs -= 1 << nslash;
+				else
+					nslash = 0;
+				nslash += 4;
+				adrs += 1 << nslash;
+				break;
+			case '\\':
+				if (nslash < 0)
+					adrs += 1 << -nslash;
+				else
+					nslash = 0;
+				nslash -= 4;
+				adrs -= 1 << -nslash;
+				break;
+			case 'm':
+				scanhex((void *)&adrs);
+				break;
+			case 'n':
+				mnoread = 1;
+				break;
+			case 'r':
+				brev = !brev;
+				break;
+			case '<':
+				n = size;
+				scanhex(&n);
+				adrs -= n;
+				break;
+			case '>':
+				n = size;
+				scanhex(&n);
+				adrs += n;
+				break;
+			case '?':
+				printf(memex_subcmd_help_string);
+				break;
+			}
+		}
+		adrs += inc;
+	}
+}
+
+static int
+bsesc(void)
+{
+	int c;
+
+	c = inchar();
+	switch( c ){
+	case 'n':	c = '\n';	break;
+	case 'r':	c = '\r';	break;
+	case 'b':	c = '\b';	break;
+	case 't':	c = '\t';	break;
+	}
+	return c;
+}
+
+static void xmon_rawdump (unsigned long adrs, long ndump)
+{
+	long n, m, r, nr;
+	unsigned char temp[16];
+
+	for (n = ndump; n > 0;) {
+		r = n < 16? n: 16;
+		nr = mread(adrs, temp, r);
+		adrs += nr;
+		for (m = 0; m < r; ++m) {
+			if (m < nr)
+				printf("%.2x", temp[m]);
+			else
+				printf("%s", fault_chars[fault_type]);
+		}
+		n -= r;
+		if (nr < r)
+			break;
+	}
+	printf("\n");
+}
+
+static void dump_tracing(void)
+{
+	int c;
+
+	c = inchar();
+	if (c == 'c')
+		ftrace_dump(DUMP_ORIG);
+	else
+		ftrace_dump(DUMP_ALL);
+}
+
+#ifdef CONFIG_PPC64
+static void dump_one_paca(int cpu)
+{
+	struct paca_struct *p;
+#ifdef CONFIG_PPC_64S_HASH_MMU
+	int i = 0;
+#endif
+
+	if (setjmp(bus_error_jmp) != 0) {
+		printf("*** Error dumping paca for cpu 0x%x!\n", cpu);
+		return;
+	}
+
+	catch_memory_errors = 1;
+	sync();
+
+	p = paca_ptrs[cpu];
+
+	printf("paca for cpu 0x%x @ %px:\n", cpu, p);
+
+	printf(" %-*s = %s\n", 25, "possible", cpu_possible(cpu) ? "yes" : "no");
+	printf(" %-*s = %s\n", 25, "present", cpu_present(cpu) ? "yes" : "no");
+	printf(" %-*s = %s\n", 25, "online", cpu_online(cpu) ? "yes" : "no");
+
+#define DUMP(paca, name, format)				\
+	printf(" %-*s = "format"\t(0x%lx)\n", 25, #name, 18, paca->name, \
+		offsetof(struct paca_struct, name));
+
+	DUMP(p, lock_token, "%#-*x");
+	DUMP(p, paca_index, "%#-*x");
+	DUMP(p, kernel_toc, "%#-*llx");
+	DUMP(p, kernelbase, "%#-*llx");
+	DUMP(p, kernel_msr, "%#-*llx");
+	DUMP(p, emergency_sp, "%-*px");
+#ifdef CONFIG_PPC_BOOK3S_64
+	DUMP(p, nmi_emergency_sp, "%-*px");
+	DUMP(p, mc_emergency_sp, "%-*px");
+	DUMP(p, in_nmi, "%#-*x");
+	DUMP(p, in_mce, "%#-*x");
+	DUMP(p, hmi_event_available, "%#-*x");
+#endif
+	DUMP(p, data_offset, "%#-*llx");
+	DUMP(p, hw_cpu_id, "%#-*x");
+	DUMP(p, cpu_start, "%#-*x");
+	DUMP(p, kexec_state, "%#-*x");
+#ifdef CONFIG_PPC_BOOK3S_64
+#ifdef CONFIG_PPC_64S_HASH_MMU
+	if (!early_radix_enabled()) {
+		for (i = 0; i < SLB_NUM_BOLTED; i++) {
+			u64 esid, vsid;
+
+			if (!p->slb_shadow_ptr)
+				continue;
+
+			esid = be64_to_cpu(p->slb_shadow_ptr->save_area[i].esid);
+			vsid = be64_to_cpu(p->slb_shadow_ptr->save_area[i].vsid);
+
+			if (esid || vsid) {
+				printf(" %-*s[%d] = 0x%016llx 0x%016llx\n",
+				       22, "slb_shadow", i, esid, vsid);
+			}
+		}
+		DUMP(p, vmalloc_sllp, "%#-*x");
+		DUMP(p, stab_rr, "%#-*x");
+		DUMP(p, slb_used_bitmap, "%#-*x");
+		DUMP(p, slb_kern_bitmap, "%#-*x");
+
+		if (!early_cpu_has_feature(CPU_FTR_ARCH_300)) {
+			DUMP(p, slb_cache_ptr, "%#-*x");
+			for (i = 0; i < SLB_CACHE_ENTRIES; i++)
+				printf(" %-*s[%d] = 0x%016x\n",
+				       22, "slb_cache", i, p->slb_cache[i]);
+		}
+	}
+#endif
+
+	DUMP(p, rfi_flush_fallback_area, "%-*px");
+#endif
+	DUMP(p, dscr_default, "%#-*llx");
+#ifdef CONFIG_PPC_BOOK3E_64
+	DUMP(p, pgd, "%-*px");
+	DUMP(p, kernel_pgd, "%-*px");
+	DUMP(p, tcd_ptr, "%-*px");
+	DUMP(p, mc_kstack, "%-*px");
+	DUMP(p, crit_kstack, "%-*px");
+	DUMP(p, dbg_kstack, "%-*px");
+#endif
+	DUMP(p, __current, "%-*px");
+	DUMP(p, kstack, "%#-*llx");
+	printf(" %-*s = 0x%016llx\n", 25, "kstack_base", p->kstack & ~(THREAD_SIZE - 1));
+#ifdef CONFIG_STACKPROTECTOR
+	DUMP(p, canary, "%#-*lx");
+#endif
+	DUMP(p, saved_r1, "%#-*llx");
+#ifdef CONFIG_PPC_BOOK3E_64
+	DUMP(p, trap_save, "%#-*x");
+#endif
+	DUMP(p, irq_soft_mask, "%#-*x");
+	DUMP(p, irq_happened, "%#-*x");
+#ifdef CONFIG_MMIOWB
+	DUMP(p, mmiowb_state.nesting_count, "%#-*x");
+	DUMP(p, mmiowb_state.mmiowb_pending, "%#-*x");
+#endif
+	DUMP(p, irq_work_pending, "%#-*x");
+	DUMP(p, sprg_vdso, "%#-*llx");
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	DUMP(p, tm_scratch, "%#-*llx");
+#endif
+
+#ifdef CONFIG_PPC_POWERNV
+	DUMP(p, idle_state, "%#-*lx");
+	if (!early_cpu_has_feature(CPU_FTR_ARCH_300)) {
+		DUMP(p, thread_idle_state, "%#-*x");
+		DUMP(p, subcore_sibling_mask, "%#-*x");
+	} else {
+#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
+		DUMP(p, requested_psscr, "%#-*llx");
+		DUMP(p, dont_stop.counter, "%#-*x");
+#endif
+	}
+#endif
+
+	DUMP(p, accounting.utime, "%#-*lx");
+	DUMP(p, accounting.stime, "%#-*lx");
+#ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
+	DUMP(p, accounting.utime_scaled, "%#-*lx");
+#endif
+	DUMP(p, accounting.starttime, "%#-*lx");
+	DUMP(p, accounting.starttime_user, "%#-*lx");
+#ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
+	DUMP(p, accounting.startspurr, "%#-*lx");
+	DUMP(p, accounting.utime_sspurr, "%#-*lx");
+#endif
+	DUMP(p, accounting.steal_time, "%#-*lx");
+#undef DUMP
+
+	catch_memory_errors = 0;
+	sync();
+}
+
+static void dump_all_pacas(void)
+{
+	int cpu;
+
+	if (num_possible_cpus() == 0) {
+		printf("No possible cpus, use 'dp #' to dump individual cpus\n");
+		return;
+	}
+
+	for_each_possible_cpu(cpu)
+		dump_one_paca(cpu);
+}
+
+static void dump_pacas(void)
+{
+	unsigned long num;
+	int c;
+
+	c = inchar();
+	if (c == 'a') {
+		dump_all_pacas();
+		return;
+	}
+
+	termch = c;	/* Put c back, it wasn't 'a' */
+
+	if (scanhex(&num))
+		dump_one_paca(num);
+	else
+		dump_one_paca(xmon_owner);
+}
+#endif
+
+#ifdef CONFIG_PPC_POWERNV
+static void dump_one_xive(int cpu)
+{
+	unsigned int hwid = get_hard_smp_processor_id(cpu);
+	bool hv = cpu_has_feature(CPU_FTR_HVMODE);
+
+	if (hv) {
+		opal_xive_dump(XIVE_DUMP_TM_HYP, hwid);
+		opal_xive_dump(XIVE_DUMP_TM_POOL, hwid);
+		opal_xive_dump(XIVE_DUMP_TM_OS, hwid);
+		opal_xive_dump(XIVE_DUMP_TM_USER, hwid);
+		opal_xive_dump(XIVE_DUMP_VP, hwid);
+		opal_xive_dump(XIVE_DUMP_EMU_STATE, hwid);
+	}
+
+	if (setjmp(bus_error_jmp) != 0) {
+		catch_memory_errors = 0;
+		printf("*** Error dumping xive on cpu %d\n", cpu);
+		return;
+	}
+
+	catch_memory_errors = 1;
+	sync();
+	xmon_xive_do_dump(cpu);
+	sync();
+	__delay(200);
+	catch_memory_errors = 0;
+}
+
+static void dump_all_xives(void)
+{
+	int cpu;
+
+	if (num_online_cpus() == 0) {
+		printf("No possible cpus, use 'dx #' to dump individual cpus\n");
+		return;
+	}
+
+	for_each_online_cpu(cpu)
+		dump_one_xive(cpu);
+}
+
+static void dump_xives(void)
+{
+	unsigned long num;
+	int c;
+
+	if (!xive_enabled()) {
+		printf("Xive disabled on this system\n");
+		return;
+	}
+
+	c = inchar();
+	if (c == 'a') {
+		dump_all_xives();
+		return;
+	} else if (c == 'i') {
+		if (scanhex(&num))
+			xmon_xive_get_irq_config(num, NULL);
+		else
+			xmon_xive_get_irq_all();
+		return;
+	}
+
+	termch = c;	/* Put c back, it wasn't 'a' */
+
+	if (scanhex(&num))
+		dump_one_xive(num);
+	else
+		dump_one_xive(xmon_owner);
+}
+#endif /* CONFIG_PPC_POWERNV */
+
+static void dump_by_size(unsigned long addr, long count, int size)
+{
+	unsigned char temp[16];
+	int i, j;
+	u64 val;
+
+	count = ALIGN(count, 16);
+
+	for (i = 0; i < count; i += 16, addr += 16) {
+		printf(REG, addr);
+
+		if (mread(addr, temp, 16) != 16) {
+			printf("\nFaulted reading %d bytes from 0x"REG"\n", 16, addr);
+			return;
+		}
+
+		for (j = 0; j < 16; j += size) {
+			putchar(' ');
+			switch (size) {
+			case 1: val = temp[j]; break;
+			case 2: val = *(u16 *)&temp[j]; break;
+			case 4: val = *(u32 *)&temp[j]; break;
+			case 8: val = *(u64 *)&temp[j]; break;
+			default: val = 0;
+			}
+
+			printf("%0*llx", size * 2, val);
+		}
+		printf("  |");
+		for (j = 0; j < 16; ++j) {
+			val = temp[j];
+			putchar(' ' <= val && val <= '~' ? val : '.');
+		}
+		printf("|\n");
+	}
+}
+
+static void
+dump(void)
+{
+	static char last[] = { "d?\n" };
+	int c;
+
+	c = inchar();
+
+#ifdef CONFIG_PPC64
+	if (c == 'p') {
+		xmon_start_pagination();
+		dump_pacas();
+		xmon_end_pagination();
+		return;
+	}
+#endif
+#ifdef CONFIG_PPC_POWERNV
+	if (c == 'x') {
+		xmon_start_pagination();
+		dump_xives();
+		xmon_end_pagination();
+		return;
+	}
+#endif
+
+	if (c == 't') {
+		dump_tracing();
+		return;
+	}
+
+	if (c == '\n')
+		termch = c;
+
+	scanhex((void *)&adrs);
+	if (termch != '\n')
+		termch = 0;
+	if (c == 'i') {
+		scanhex(&nidump);
+		if (nidump == 0)
+			nidump = 16;
+		else if (nidump > MAX_IDUMP)
+			nidump = MAX_IDUMP;
+		adrs += ppc_inst_dump(adrs, nidump, 1);
+		last_cmd = "di\n";
+	} else if (c == 'l') {
+		dump_log_buf();
+	} else if (c == 'o') {
+		dump_opal_msglog();
+	} else if (c == 'v') {
+		/* dump virtual to physical translation */
+		show_pte(adrs);
+	} else if (c == 'r') {
+		scanhex(&ndump);
+		if (ndump == 0)
+			ndump = 64;
+		xmon_rawdump(adrs, ndump);
+		adrs += ndump;
+		last_cmd = "dr\n";
+	} else {
+		scanhex(&ndump);
+		if (ndump == 0)
+			ndump = 64;
+		else if (ndump > MAX_DUMP)
+			ndump = MAX_DUMP;
+
+		switch (c) {
+		case '8':
+		case '4':
+		case '2':
+		case '1':
+			ndump = ALIGN(ndump, 16);
+			dump_by_size(adrs, ndump, c - '0');
+			last[1] = c;
+			last_cmd = last;
+			break;
+		default:
+			prdump(adrs, ndump);
+			last_cmd = "d\n";
+		}
+
+		adrs += ndump;
+	}
+}
+
+static void
+prdump(unsigned long adrs, long ndump)
+{
+	long n, m, c, r, nr;
+	unsigned char temp[16];
+
+	for (n = ndump; n > 0;) {
+		printf(REG, adrs);
+		putchar(' ');
+		r = n < 16? n: 16;
+		nr = mread(adrs, temp, r);
+		adrs += nr;
+		for (m = 0; m < r; ++m) {
+			if ((m & (sizeof(long) - 1)) == 0 && m > 0)
+				putchar(' ');
+			if (m < nr)
+				printf("%.2x", temp[m]);
+			else
+				printf("%s", fault_chars[fault_type]);
+		}
+		for (; m < 16; ++m) {
+			if ((m & (sizeof(long) - 1)) == 0)
+				putchar(' ');
+			printf("  ");
+		}
+		printf("  |");
+		for (m = 0; m < r; ++m) {
+			if (m < nr) {
+				c = temp[m];
+				putchar(' ' <= c && c <= '~'? c: '.');
+			} else
+				putchar(' ');
+		}
+		n -= r;
+		for (; m < 16; ++m)
+			putchar(' ');
+		printf("|\n");
+		if (nr < r)
+			break;
+	}
+}
+
+typedef int (*instruction_dump_func)(unsigned long inst, unsigned long addr);
+
+static int
+generic_inst_dump(unsigned long adr, long count, int praddr,
+			instruction_dump_func dump_func)
+{
+	int nr, dotted;
+	unsigned long first_adr;
+	ppc_inst_t inst, last_inst = ppc_inst(0);
+
+	dotted = 0;
+	for (first_adr = adr; count > 0; --count, adr += ppc_inst_len(inst)) {
+		nr = mread_instr(adr, &inst);
+		if (nr == 0) {
+			if (praddr) {
+				const char *x = fault_chars[fault_type];
+				printf(REG"  %s%s%s%s\n", adr, x, x, x, x);
+			}
+			break;
+		}
+		if (adr > first_adr && ppc_inst_equal(inst, last_inst)) {
+			if (!dotted) {
+				printf(" ...\n");
+				dotted = 1;
+			}
+			continue;
+		}
+		dotted = 0;
+		last_inst = inst;
+		if (praddr)
+			printf(REG"  %08lx", adr, ppc_inst_as_ulong(inst));
+		printf("\t");
+		if (!ppc_inst_prefixed(inst))
+			dump_func(ppc_inst_val(inst), adr);
+		else
+			dump_func(ppc_inst_as_ulong(inst), adr);
+		printf("\n");
+	}
+	return adr - first_adr;
+}
+
+static int
+ppc_inst_dump(unsigned long adr, long count, int praddr)
+{
+	return generic_inst_dump(adr, count, praddr, print_insn_powerpc);
+}
+
+void
+print_address(unsigned long addr)
+{
+	xmon_print_symbol(addr, "\t# ", "");
+}
+
+static void
+dump_log_buf(void)
+{
+	struct kmsg_dump_iter iter;
+	static unsigned char buf[1024];
+	size_t len;
+
+	if (setjmp(bus_error_jmp) != 0) {
+		printf("Error dumping printk buffer!\n");
+		return;
+	}
+
+	catch_memory_errors = 1;
+	sync();
+
+	kmsg_dump_rewind(&iter);
+	xmon_start_pagination();
+	while (kmsg_dump_get_line(&iter, false, buf, sizeof(buf), &len)) {
+		buf[len] = '\0';
+		printf("%s", buf);
+	}
+	xmon_end_pagination();
+
+	sync();
+	/* wait a little while to see if we get a machine check */
+	__delay(200);
+	catch_memory_errors = 0;
+}
+
+#ifdef CONFIG_PPC_POWERNV
+static void dump_opal_msglog(void)
+{
+	unsigned char buf[128];
+	ssize_t res;
+	volatile loff_t pos = 0;
+
+	if (!firmware_has_feature(FW_FEATURE_OPAL)) {
+		printf("Machine is not running OPAL firmware.\n");
+		return;
+	}
+
+	if (setjmp(bus_error_jmp) != 0) {
+		printf("Error dumping OPAL msglog!\n");
+		return;
+	}
+
+	catch_memory_errors = 1;
+	sync();
+
+	xmon_start_pagination();
+	while ((res = opal_msglog_copy(buf, pos, sizeof(buf) - 1))) {
+		if (res < 0) {
+			printf("Error dumping OPAL msglog! Error: %zd\n", res);
+			break;
+		}
+		buf[res] = '\0';
+		printf("%s", buf);
+		pos += res;
+	}
+	xmon_end_pagination();
+
+	sync();
+	/* wait a little while to see if we get a machine check */
+	__delay(200);
+	catch_memory_errors = 0;
+}
+#endif
+
+/*
+ * Memory operations - move, set, print differences
+ */
+static unsigned long mdest;		/* destination address */
+static unsigned long msrc;		/* source address */
+static unsigned long mval;		/* byte value to set memory to */
+static unsigned long mcount;		/* # bytes to affect */
+static unsigned long mdiffs;		/* max # differences to print */
+
+static void
+memops(int cmd)
+{
+	scanhex((void *)&mdest);
+	if( termch != '\n' )
+		termch = 0;
+	scanhex((void *)(cmd == 's'? &mval: &msrc));
+	if( termch != '\n' )
+		termch = 0;
+	scanhex((void *)&mcount);
+	switch( cmd ){
+	case 'm':
+		if (xmon_is_ro) {
+			printf(xmon_ro_msg);
+			break;
+		}
+		memmove((void *)mdest, (void *)msrc, mcount);
+		break;
+	case 's':
+		if (xmon_is_ro) {
+			printf(xmon_ro_msg);
+			break;
+		}
+		memset((void *)mdest, mval, mcount);
+		break;
+	case 'd':
+		if( termch != '\n' )
+			termch = 0;
+		scanhex((void *)&mdiffs);
+		memdiffs((unsigned char *)mdest, (unsigned char *)msrc, mcount, mdiffs);
+		break;
+	}
+}
+
+static void
+memdiffs(unsigned char *p1, unsigned char *p2, unsigned nb, unsigned maxpr)
+{
+	unsigned n, prt;
+
+	prt = 0;
+	for( n = nb; n > 0; --n )
+		if( *p1++ != *p2++ )
+			if( ++prt <= maxpr )
+				printf("%px %.2x # %px %.2x\n", p1 - 1,
+					p1[-1], p2 - 1, p2[-1]);
+	if( prt > maxpr )
+		printf("Total of %d differences\n", prt);
+}
+
+static unsigned mend;
+static unsigned mask;
+
+static void
+memlocate(void)
+{
+	unsigned a, n;
+	unsigned char val[4];
+
+	last_cmd = "ml";
+	scanhex((void *)&mdest);
+	if (termch != '\n') {
+		termch = 0;
+		scanhex((void *)&mend);
+		if (termch != '\n') {
+			termch = 0;
+			scanhex((void *)&mval);
+			mask = ~0;
+			if (termch != '\n') termch = 0;
+			scanhex((void *)&mask);
+		}
+	}
+	n = 0;
+	for (a = mdest; a < mend; a += 4) {
+		if (mread(a, val, 4) == 4
+			&& ((GETWORD(val) ^ mval) & mask) == 0) {
+			printf("%.16x:  %.16x\n", a, GETWORD(val));
+			if (++n >= 10)
+				break;
+		}
+	}
+}
+
+static unsigned long mskip = 0x1000;
+static unsigned long mlim = 0xffffffff;
+
+static void
+memzcan(void)
+{
+	unsigned char v;
+	unsigned a;
+	int ok, ook;
+
+	scanhex(&mdest);
+	if (termch != '\n') termch = 0;
+	scanhex(&mskip);
+	if (termch != '\n') termch = 0;
+	scanhex(&mlim);
+	ook = 0;
+	for (a = mdest; a < mlim; a += mskip) {
+		ok = mread(a, &v, 1);
+		if (ok && !ook) {
+			printf("%.8x .. ", a);
+		} else if (!ok && ook)
+			printf("%.8lx\n", a - mskip);
+		ook = ok;
+		if (a + mskip < a)
+			break;
+	}
+	if (ook)
+		printf("%.8lx\n", a - mskip);
+}
+
+static void show_task(struct task_struct *volatile tsk)
+{
+	unsigned int p_state = READ_ONCE(tsk->__state);
+	char state;
+
+	/*
+	 * Cloned from kdb_task_state_char(), which is not entirely
+	 * appropriate for calling from xmon. This could be moved
+	 * to a common, generic, routine used by both.
+	 */
+	state = (p_state == TASK_RUNNING) ? 'R' :
+		(p_state & TASK_UNINTERRUPTIBLE) ? 'D' :
+		(p_state & TASK_STOPPED) ? 'T' :
+		(p_state & TASK_TRACED) ? 'C' :
+		(tsk->exit_state & EXIT_ZOMBIE) ? 'Z' :
+		(tsk->exit_state & EXIT_DEAD) ? 'E' :
+		(p_state & TASK_INTERRUPTIBLE) ? 'S' : '?';
+
+	printf("%16px %16lx %16px %6d %6d %c %2d %s\n", tsk,
+		tsk->thread.ksp, tsk->thread.regs,
+		tsk->pid, rcu_dereference(tsk->parent)->pid,
+		state, task_cpu(tsk),
+		tsk->comm);
+}
+
+#ifdef CONFIG_PPC_BOOK3S_64
+static void format_pte(void *ptep, unsigned long pte)
+{
+	pte_t entry = __pte(pte);
+
+	printf("ptep @ 0x%016lx = 0x%016lx\n", (unsigned long)ptep, pte);
+	printf("Maps physical address = 0x%016lx\n", pte & PTE_RPN_MASK);
+
+	printf("Flags = %s%s%s%s%s\n",
+	       pte_young(entry) ? "Accessed " : "",
+	       pte_dirty(entry) ? "Dirty " : "",
+	       pte_read(entry)  ? "Read " : "",
+	       pte_write(entry) ? "Write " : "",
+	       pte_exec(entry)  ? "Exec " : "");
+}
+
+static void show_pte(unsigned long addr)
+{
+	unsigned long tskv = 0;
+	struct task_struct *volatile tsk = NULL;
+	struct mm_struct *mm;
+	pgd_t *pgdp;
+	p4d_t *p4dp;
+	pud_t *pudp;
+	pmd_t *pmdp;
+	pte_t *ptep;
+
+	if (!scanhex(&tskv))
+		mm = &init_mm;
+	else
+		tsk = (struct task_struct *)tskv;
+
+	if (tsk == NULL)
+		mm = &init_mm;
+	else
+		mm = tsk->active_mm;
+
+	if (setjmp(bus_error_jmp) != 0) {
+		catch_memory_errors = 0;
+		printf("*** Error dumping pte for task %px\n", tsk);
+		return;
+	}
+
+	catch_memory_errors = 1;
+	sync();
+
+	if (mm == &init_mm)
+		pgdp = pgd_offset_k(addr);
+	else
+		pgdp = pgd_offset(mm, addr);
+
+	p4dp = p4d_offset(pgdp, addr);
+
+	if (p4d_none(*p4dp)) {
+		printf("No valid P4D\n");
+		return;
+	}
+
+	if (p4d_is_leaf(*p4dp)) {
+		format_pte(p4dp, p4d_val(*p4dp));
+		return;
+	}
+
+	printf("p4dp @ 0x%px = 0x%016lx\n", p4dp, p4d_val(*p4dp));
+
+	pudp = pud_offset(p4dp, addr);
+
+	if (pud_none(*pudp)) {
+		printf("No valid PUD\n");
+		return;
+	}
+
+	if (pud_is_leaf(*pudp)) {
+		format_pte(pudp, pud_val(*pudp));
+		return;
+	}
+
+	printf("pudp @ 0x%px = 0x%016lx\n", pudp, pud_val(*pudp));
+
+	pmdp = pmd_offset(pudp, addr);
+
+	if (pmd_none(*pmdp)) {
+		printf("No valid PMD\n");
+		return;
+	}
+
+	if (pmd_is_leaf(*pmdp)) {
+		format_pte(pmdp, pmd_val(*pmdp));
+		return;
+	}
+	printf("pmdp @ 0x%px = 0x%016lx\n", pmdp, pmd_val(*pmdp));
+
+	ptep = pte_offset_map(pmdp, addr);
+	if (pte_none(*ptep)) {
+		printf("no valid PTE\n");
+		return;
+	}
+
+	format_pte(ptep, pte_val(*ptep));
+
+	sync();
+	__delay(200);
+	catch_memory_errors = 0;
+}
+#else
+static void show_pte(unsigned long addr)
+{
+	printf("show_pte not yet implemented\n");
+}
+#endif /* CONFIG_PPC_BOOK3S_64 */
+
+static void show_tasks(void)
+{
+	unsigned long tskv;
+	struct task_struct *volatile tsk = NULL;
+
+	printf("     task_struct     ->thread.ksp    ->thread.regs    PID   PPID S  P CMD\n");
+
+	if (scanhex(&tskv))
+		tsk = (struct task_struct *)tskv;
+
+	if (setjmp(bus_error_jmp) != 0) {
+		catch_memory_errors = 0;
+		printf("*** Error dumping task %px\n", tsk);
+		return;
+	}
+
+	catch_memory_errors = 1;
+	sync();
+
+	if (tsk)
+		show_task(tsk);
+	else
+		for_each_process(tsk)
+			show_task(tsk);
+
+	sync();
+	__delay(200);
+	catch_memory_errors = 0;
+}
+
+static void proccall(void)
+{
+	unsigned long args[8];
+	unsigned long ret;
+	int i;
+	typedef unsigned long (*callfunc_t)(unsigned long, unsigned long,
+			unsigned long, unsigned long, unsigned long,
+			unsigned long, unsigned long, unsigned long);
+	callfunc_t func;
+
+	if (!scanhex(&adrs))
+		return;
+	if (termch != '\n')
+		termch = 0;
+	for (i = 0; i < 8; ++i)
+		args[i] = 0;
+	for (i = 0; i < 8; ++i) {
+		if (!scanhex(&args[i]) || termch == '\n')
+			break;
+		termch = 0;
+	}
+	func = (callfunc_t) adrs;
+	ret = 0;
+	if (setjmp(bus_error_jmp) == 0) {
+		catch_memory_errors = 1;
+		sync();
+		ret = func(args[0], args[1], args[2], args[3],
+			   args[4], args[5], args[6], args[7]);
+		sync();
+		printf("return value is 0x%lx\n", ret);
+	} else {
+		printf("*** %x exception occurred\n", fault_except);
+	}
+	catch_memory_errors = 0;
+}
+
+/* Input scanning routines */
+int
+skipbl(void)
+{
+	int c;
+
+	if( termch != 0 ){
+		c = termch;
+		termch = 0;
+	} else
+		c = inchar();
+	while( c == ' ' || c == '\t' )
+		c = inchar();
+	return c;
+}
+
+#define N_PTREGS	44
+static const char *regnames[N_PTREGS] = {
+	"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
+	"r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
+	"r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23",
+	"r24", "r25", "r26", "r27", "r28", "r29", "r30", "r31",
+	"pc", "msr", "or3", "ctr", "lr", "xer", "ccr",
+#ifdef CONFIG_PPC64
+	"softe",
+#else
+	"mq",
+#endif
+	"trap", "dar", "dsisr", "res"
+};
+
+int
+scanhex(unsigned long *vp)
+{
+	int c, d;
+	unsigned long v;
+
+	c = skipbl();
+	if (c == '%') {
+		/* parse register name */
+		char regname[8];
+		int i;
+
+		for (i = 0; i < sizeof(regname) - 1; ++i) {
+			c = inchar();
+			if (!isalnum(c)) {
+				termch = c;
+				break;
+			}
+			regname[i] = c;
+		}
+		regname[i] = 0;
+		i = match_string(regnames, N_PTREGS, regname);
+		if (i < 0) {
+			printf("invalid register name '%%%s'\n", regname);
+			return 0;
+		}
+		if (xmon_regs == NULL) {
+			printf("regs not available\n");
+			return 0;
+		}
+		*vp = ((unsigned long *)xmon_regs)[i];
+		return 1;
+	}
+
+	/* skip leading "0x" if any */
+
+	if (c == '0') {
+		c = inchar();
+		if (c == 'x') {
+			c = inchar();
+		} else {
+			d = hexdigit(c);
+			if (d == EOF) {
+				termch = c;
+				*vp = 0;
+				return 1;
+			}
+		}
+	} else if (c == '$') {
+		int i;
+		for (i=0; i<63; i++) {
+			c = inchar();
+			if (isspace(c) || c == '\0') {
+				termch = c;
+				break;
+			}
+			tmpstr[i] = c;
+		}
+		tmpstr[i++] = 0;
+		*vp = 0;
+		if (setjmp(bus_error_jmp) == 0) {
+			catch_memory_errors = 1;
+			sync();
+			*vp = kallsyms_lookup_name(tmpstr);
+			sync();
+		}
+		catch_memory_errors = 0;
+		if (!(*vp)) {
+			printf("unknown symbol '%s'\n", tmpstr);
+			return 0;
+		}
+		return 1;
+	}
+
+	d = hexdigit(c);
+	if (d == EOF) {
+		termch = c;
+		return 0;
+	}
+	v = 0;
+	do {
+		v = (v << 4) + d;
+		c = inchar();
+		d = hexdigit(c);
+	} while (d != EOF);
+	termch = c;
+	*vp = v;
+	return 1;
+}
+
+static void
+scannl(void)
+{
+	int c;
+
+	c = termch;
+	termch = 0;
+	while( c != '\n' )
+		c = inchar();
+}
+
+static int hexdigit(int c)
+{
+	if( '0' <= c && c <= '9' )
+		return c - '0';
+	if( 'A' <= c && c <= 'F' )
+		return c - ('A' - 10);
+	if( 'a' <= c && c <= 'f' )
+		return c - ('a' - 10);
+	return EOF;
+}
+
+void
+getstring(char *s, int size)
+{
+	int c;
+
+	c = skipbl();
+	if (c == '\n') {
+		*s = 0;
+		return;
+	}
+
+	do {
+		if( size > 1 ){
+			*s++ = c;
+			--size;
+		}
+		c = inchar();
+	} while( c != ' ' && c != '\t' && c != '\n' );
+	termch = c;
+	*s = 0;
+}
+
+static char line[256];
+static char *lineptr;
+
+static void
+flush_input(void)
+{
+	lineptr = NULL;
+}
+
+static int
+inchar(void)
+{
+	if (lineptr == NULL || *lineptr == 0) {
+		if (xmon_gets(line, sizeof(line)) == NULL) {
+			lineptr = NULL;
+			return EOF;
+		}
+		lineptr = line;
+	}
+	return *lineptr++;
+}
+
+static void
+take_input(char *str)
+{
+	lineptr = str;
+}
+
+
+static void
+symbol_lookup(void)
+{
+	int type = inchar();
+	unsigned long addr, cpu;
+	void __percpu *ptr = NULL;
+	static char tmp[64];
+
+	switch (type) {
+	case 'a':
+		if (scanhex(&addr))
+			xmon_print_symbol(addr, ": ", "\n");
+		termch = 0;
+		break;
+	case 's':
+		getstring(tmp, 64);
+		if (setjmp(bus_error_jmp) == 0) {
+			catch_memory_errors = 1;
+			sync();
+			addr = kallsyms_lookup_name(tmp);
+			if (addr)
+				printf("%s: %lx\n", tmp, addr);
+			else
+				printf("Symbol '%s' not found.\n", tmp);
+			sync();
+		}
+		catch_memory_errors = 0;
+		termch = 0;
+		break;
+	case 'p':
+		getstring(tmp, 64);
+		if (setjmp(bus_error_jmp) == 0) {
+			catch_memory_errors = 1;
+			sync();
+			ptr = (void __percpu *)kallsyms_lookup_name(tmp);
+			sync();
+		}
+
+		if (ptr &&
+		    ptr >= (void __percpu *)__per_cpu_start &&
+		    ptr < (void __percpu *)__per_cpu_end)
+		{
+			if (scanhex(&cpu) && cpu < num_possible_cpus()) {
+				addr = (unsigned long)per_cpu_ptr(ptr, cpu);
+			} else {
+				cpu = raw_smp_processor_id();
+				addr = (unsigned long)this_cpu_ptr(ptr);
+			}
+
+			printf("%s for cpu 0x%lx: %lx\n", tmp, cpu, addr);
+		} else {
+			printf("Percpu symbol '%s' not found.\n", tmp);
+		}
+
+		catch_memory_errors = 0;
+		termch = 0;
+		break;
+	}
+}
+
+
+/* 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 *volatile name = NULL;
+	unsigned long offset, size;
+
+	printf(REG, address);
+	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;
+
+	if (name) {
+		printf("%s%s+%#lx/%#lx", mid, name, offset, size);
+		if (modname)
+			printf(" [%s]", modname);
+	}
+	printf("%s", after);
+}
+
+#ifdef CONFIG_PPC_64S_HASH_MMU
+void dump_segments(void)
+{
+	int i;
+	unsigned long esid,vsid;
+	unsigned long llp;
+
+	printf("SLB contents of cpu 0x%x\n", smp_processor_id());
+
+	for (i = 0; i < mmu_slb_size; i++) {
+		asm volatile("slbmfee  %0,%1" : "=r" (esid) : "r" (i));
+		asm volatile("slbmfev  %0,%1" : "=r" (vsid) : "r" (i));
+
+		if (!esid && !vsid)
+			continue;
+
+		printf("%02d %016lx %016lx", i, esid, vsid);
+
+		if (!(esid & SLB_ESID_V)) {
+			printf("\n");
+			continue;
+		}
+
+		llp = vsid & SLB_VSID_LLP;
+		if (vsid & SLB_VSID_B_1T) {
+			printf("  1T  ESID=%9lx  VSID=%13lx LLP:%3lx \n",
+				GET_ESID_1T(esid),
+				(vsid & ~SLB_VSID_B) >> SLB_VSID_SHIFT_1T,
+				llp);
+		} else {
+			printf(" 256M ESID=%9lx  VSID=%13lx LLP:%3lx \n",
+				GET_ESID(esid),
+				(vsid & ~SLB_VSID_B) >> SLB_VSID_SHIFT,
+				llp);
+		}
+	}
+}
+#endif
+
+#ifdef CONFIG_PPC_BOOK3S_32
+void dump_segments(void)
+{
+	int i;
+
+	printf("sr0-15 =");
+	for (i = 0; i < 16; ++i)
+		printf(" %x", mfsr(i << 28));
+	printf("\n");
+}
+#endif
+
+#ifdef CONFIG_44x
+static void dump_tlb_44x(void)
+{
+	int i;
+
+	for (i = 0; i < PPC44x_TLB_SIZE; i++) {
+		unsigned long w0,w1,w2;
+		asm volatile("tlbre  %0,%1,0" : "=r" (w0) : "r" (i));
+		asm volatile("tlbre  %0,%1,1" : "=r" (w1) : "r" (i));
+		asm volatile("tlbre  %0,%1,2" : "=r" (w2) : "r" (i));
+		printf("[%02x] %08lx %08lx %08lx ", i, w0, w1, w2);
+		if (w0 & PPC44x_TLB_VALID) {
+			printf("V %08lx -> %01lx%08lx %c%c%c%c%c",
+			       w0 & PPC44x_TLB_EPN_MASK,
+			       w1 & PPC44x_TLB_ERPN_MASK,
+			       w1 & PPC44x_TLB_RPN_MASK,
+			       (w2 & PPC44x_TLB_W) ? 'W' : 'w',
+			       (w2 & PPC44x_TLB_I) ? 'I' : 'i',
+			       (w2 & PPC44x_TLB_M) ? 'M' : 'm',
+			       (w2 & PPC44x_TLB_G) ? 'G' : 'g',
+			       (w2 & PPC44x_TLB_E) ? 'E' : 'e');
+		}
+		printf("\n");
+	}
+}
+#endif /* CONFIG_44x */
+
+#ifdef CONFIG_PPC_BOOK3E_64
+static void dump_tlb_book3e(void)
+{
+	u32 mmucfg, pidmask, lpidmask;
+	u64 ramask;
+	int i, tlb, ntlbs, pidsz, lpidsz, rasz, lrat = 0;
+	int mmu_version;
+	static const char *pgsz_names[] = {
+		"  1K",
+		"  2K",
+		"  4K",
+		"  8K",
+		" 16K",
+		" 32K",
+		" 64K",
+		"128K",
+		"256K",
+		"512K",
+		"  1M",
+		"  2M",
+		"  4M",
+		"  8M",
+		" 16M",
+		" 32M",
+		" 64M",
+		"128M",
+		"256M",
+		"512M",
+		"  1G",
+		"  2G",
+		"  4G",
+		"  8G",
+		" 16G",
+		" 32G",
+		" 64G",
+		"128G",
+		"256G",
+		"512G",
+		"  1T",
+		"  2T",
+	};
+
+	/* Gather some infos about the MMU */
+	mmucfg = mfspr(SPRN_MMUCFG);
+	mmu_version = (mmucfg & 3) + 1;
+	ntlbs = ((mmucfg >> 2) & 3) + 1;
+	pidsz = ((mmucfg >> 6) & 0x1f) + 1;
+	lpidsz = (mmucfg >> 24) & 0xf;
+	rasz = (mmucfg >> 16) & 0x7f;
+	if ((mmu_version > 1) && (mmucfg & 0x10000))
+		lrat = 1;
+	printf("Book3E MMU MAV=%d.0,%d TLBs,%d-bit PID,%d-bit LPID,%d-bit RA\n",
+	       mmu_version, ntlbs, pidsz, lpidsz, rasz);
+	pidmask = (1ul << pidsz) - 1;
+	lpidmask = (1ul << lpidsz) - 1;
+	ramask = (1ull << rasz) - 1;
+
+	for (tlb = 0; tlb < ntlbs; tlb++) {
+		u32 tlbcfg;
+		int nent, assoc, new_cc = 1;
+		printf("TLB %d:\n------\n", tlb);
+		switch(tlb) {
+		case 0:
+			tlbcfg = mfspr(SPRN_TLB0CFG);
+			break;
+		case 1:
+			tlbcfg = mfspr(SPRN_TLB1CFG);
+			break;
+		case 2:
+			tlbcfg = mfspr(SPRN_TLB2CFG);
+			break;
+		case 3:
+			tlbcfg = mfspr(SPRN_TLB3CFG);
+			break;
+		default:
+			printf("Unsupported TLB number !\n");
+			continue;
+		}
+		nent = tlbcfg & 0xfff;
+		assoc = (tlbcfg >> 24) & 0xff;
+		for (i = 0; i < nent; i++) {
+			u32 mas0 = MAS0_TLBSEL(tlb);
+			u32 mas1 = MAS1_TSIZE(BOOK3E_PAGESZ_4K);
+			u64 mas2 = 0;
+			u64 mas7_mas3;
+			int esel = i, cc = i;
+
+			if (assoc != 0) {
+				cc = i / assoc;
+				esel = i % assoc;
+				mas2 = cc * 0x1000;
+			}
+
+			mas0 |= MAS0_ESEL(esel);
+			mtspr(SPRN_MAS0, mas0);
+			mtspr(SPRN_MAS1, mas1);
+			mtspr(SPRN_MAS2, mas2);
+			asm volatile("tlbre  0,0,0" : : : "memory");
+			mas1 = mfspr(SPRN_MAS1);
+			mas2 = mfspr(SPRN_MAS2);
+			mas7_mas3 = mfspr(SPRN_MAS7_MAS3);
+			if (assoc && (i % assoc) == 0)
+				new_cc = 1;
+			if (!(mas1 & MAS1_VALID))
+				continue;
+			if (assoc == 0)
+				printf("%04x- ", i);
+			else if (new_cc)
+				printf("%04x-%c", cc, 'A' + esel);
+			else
+				printf("    |%c", 'A' + esel);
+			new_cc = 0;
+			printf(" %016llx %04x %s %c%c AS%c",
+			       mas2 & ~0x3ffull,
+			       (mas1 >> 16) & 0x3fff,
+			       pgsz_names[(mas1 >> 7) & 0x1f],
+			       mas1 & MAS1_IND ? 'I' : ' ',
+			       mas1 & MAS1_IPROT ? 'P' : ' ',
+			       mas1 & MAS1_TS ? '1' : '0');
+			printf(" %c%c%c%c%c%c%c",
+			       mas2 & MAS2_X0 ? 'a' : ' ',
+			       mas2 & MAS2_X1 ? 'v' : ' ',
+			       mas2 & MAS2_W  ? 'w' : ' ',
+			       mas2 & MAS2_I  ? 'i' : ' ',
+			       mas2 & MAS2_M  ? 'm' : ' ',
+			       mas2 & MAS2_G  ? 'g' : ' ',
+			       mas2 & MAS2_E  ? 'e' : ' ');
+			printf(" %016llx", mas7_mas3 & ramask & ~0x7ffull);
+			if (mas1 & MAS1_IND)
+				printf(" %s\n",
+				       pgsz_names[(mas7_mas3 >> 1) & 0x1f]);
+			else
+				printf(" U%c%c%c S%c%c%c\n",
+				       mas7_mas3 & MAS3_UX ? 'x' : ' ',
+				       mas7_mas3 & MAS3_UW ? 'w' : ' ',
+				       mas7_mas3 & MAS3_UR ? 'r' : ' ',
+				       mas7_mas3 & MAS3_SX ? 'x' : ' ',
+				       mas7_mas3 & MAS3_SW ? 'w' : ' ',
+				       mas7_mas3 & MAS3_SR ? 'r' : ' ');
+		}
+	}
+}
+#endif /* CONFIG_PPC_BOOK3E_64 */
+
+static void xmon_init(int enable)
+{
+	if (enable) {
+		__debugger = xmon;
+		__debugger_ipi = xmon_ipi;
+		__debugger_bpt = xmon_bpt;
+		__debugger_sstep = xmon_sstep;
+		__debugger_iabr_match = xmon_iabr_match;
+		__debugger_break_match = xmon_break_match;
+		__debugger_fault_handler = xmon_fault_handler;
+
+#ifdef CONFIG_PPC_PSERIES
+		/*
+		 * Get the token here to avoid trying to get a lock
+		 * during the crash, causing a deadlock.
+		 */
+		set_indicator_token = rtas_token("set-indicator");
+#endif
+	} else {
+		__debugger = NULL;
+		__debugger_ipi = NULL;
+		__debugger_bpt = NULL;
+		__debugger_sstep = NULL;
+		__debugger_iabr_match = NULL;
+		__debugger_break_match = NULL;
+		__debugger_fault_handler = NULL;
+	}
+}
+
+#ifdef CONFIG_MAGIC_SYSRQ
+static void sysrq_handle_xmon(int key)
+{
+	if (xmon_is_locked_down()) {
+		clear_all_bpt();
+		xmon_init(0);
+		return;
+	}
+	/* ensure xmon is enabled */
+	xmon_init(1);
+	debugger(get_irq_regs());
+	if (!xmon_on)
+		xmon_init(0);
+}
+
+static const struct sysrq_key_op sysrq_xmon_op = {
+	.handler =	sysrq_handle_xmon,
+	.help_msg =	"xmon(x)",
+	.action_msg =	"Entering xmon",
+};
+
+static int __init setup_xmon_sysrq(void)
+{
+	register_sysrq_key('x', &sysrq_xmon_op);
+	return 0;
+}
+device_initcall(setup_xmon_sysrq);
+#endif /* CONFIG_MAGIC_SYSRQ */
+
+static void clear_all_bpt(void)
+{
+	int i;
+
+	/* clear/unpatch all breakpoints */
+	remove_bpts();
+	remove_cpu_bpts();
+
+	/* Disable all breakpoints */
+	for (i = 0; i < NBPTS; ++i)
+		bpts[i].enabled = 0;
+
+	/* Clear any data or iabr breakpoints */
+	iabr = NULL;
+	for (i = 0; i < nr_wp_slots(); i++)
+		dabr[i].enabled = 0;
+}
+
+#ifdef CONFIG_DEBUG_FS
+static int xmon_dbgfs_set(void *data, u64 val)
+{
+	xmon_on = !!val;
+	xmon_init(xmon_on);
+
+	/* make sure all breakpoints removed when disabling */
+	if (!xmon_on) {
+		clear_all_bpt();
+		get_output_lock();
+		printf("xmon: All breakpoints cleared\n");
+		release_output_lock();
+	}
+
+	return 0;
+}
+
+static int xmon_dbgfs_get(void *data, u64 *val)
+{
+	*val = xmon_on;
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(xmon_dbgfs_ops, xmon_dbgfs_get,
+			xmon_dbgfs_set, "%llu\n");
+
+static int __init setup_xmon_dbgfs(void)
+{
+	debugfs_create_file("xmon", 0600, arch_debugfs_dir, NULL,
+			    &xmon_dbgfs_ops);
+	return 0;
+}
+device_initcall(setup_xmon_dbgfs);
+#endif /* CONFIG_DEBUG_FS */
+
+static int xmon_early __initdata;
+
+static int __init early_parse_xmon(char *p)
+{
+	if (xmon_is_locked_down()) {
+		xmon_init(0);
+		xmon_early = 0;
+		xmon_on = 0;
+	} else if (!p || strncmp(p, "early", 5) == 0) {
+		/* just "xmon" is equivalent to "xmon=early" */
+		xmon_init(1);
+		xmon_early = 1;
+		xmon_on = 1;
+	} else if (strncmp(p, "on", 2) == 0) {
+		xmon_init(1);
+		xmon_on = 1;
+	} else if (strncmp(p, "rw", 2) == 0) {
+		xmon_init(1);
+		xmon_on = 1;
+		xmon_is_ro = false;
+	} else if (strncmp(p, "ro", 2) == 0) {
+		xmon_init(1);
+		xmon_on = 1;
+		xmon_is_ro = true;
+	} else if (strncmp(p, "off", 3) == 0)
+		xmon_on = 0;
+	else
+		return 1;
+
+	return 0;
+}
+early_param("xmon", early_parse_xmon);
+
+void __init xmon_setup(void)
+{
+	if (xmon_on)
+		xmon_init(1);
+	if (xmon_early)
+		debugger(NULL);
+}
+
+#ifdef CONFIG_SPU_BASE
+
+struct spu_info {
+	struct spu *spu;
+	u64 saved_mfc_sr1_RW;
+	u32 saved_spu_runcntl_RW;
+	unsigned long dump_addr;
+	u8 stopped_ok;
+};
+
+#define XMON_NUM_SPUS	16	/* Enough for current hardware */
+
+static struct spu_info spu_info[XMON_NUM_SPUS];
+
+void __init xmon_register_spus(struct list_head *list)
+{
+	struct spu *spu;
+
+	list_for_each_entry(spu, list, full_list) {
+		if (spu->number >= XMON_NUM_SPUS) {
+			WARN_ON(1);
+			continue;
+		}
+
+		spu_info[spu->number].spu = spu;
+		spu_info[spu->number].stopped_ok = 0;
+		spu_info[spu->number].dump_addr = (unsigned long)
+				spu_info[spu->number].spu->local_store;
+	}
+}
+
+static void stop_spus(void)
+{
+	struct spu *spu;
+	volatile int i;
+	u64 tmp;
+
+	for (i = 0; i < XMON_NUM_SPUS; i++) {
+		if (!spu_info[i].spu)
+			continue;
+
+		if (setjmp(bus_error_jmp) == 0) {
+			catch_memory_errors = 1;
+			sync();
+
+			spu = spu_info[i].spu;
+
+			spu_info[i].saved_spu_runcntl_RW =
+				in_be32(&spu->problem->spu_runcntl_RW);
+
+			tmp = spu_mfc_sr1_get(spu);
+			spu_info[i].saved_mfc_sr1_RW = tmp;
+
+			tmp &= ~MFC_STATE1_MASTER_RUN_CONTROL_MASK;
+			spu_mfc_sr1_set(spu, tmp);
+
+			sync();
+			__delay(200);
+
+			spu_info[i].stopped_ok = 1;
+
+			printf("Stopped spu %.2d (was %s)\n", i,
+					spu_info[i].saved_spu_runcntl_RW ?
+					"running" : "stopped");
+		} else {
+			catch_memory_errors = 0;
+			printf("*** Error stopping spu %.2d\n", i);
+		}
+		catch_memory_errors = 0;
+	}
+}
+
+static void restart_spus(void)
+{
+	struct spu *spu;
+	volatile int i;
+
+	for (i = 0; i < XMON_NUM_SPUS; i++) {
+		if (!spu_info[i].spu)
+			continue;
+
+		if (!spu_info[i].stopped_ok) {
+			printf("*** Error, spu %d was not successfully stopped"
+					", not restarting\n", i);
+			continue;
+		}
+
+		if (setjmp(bus_error_jmp) == 0) {
+			catch_memory_errors = 1;
+			sync();
+
+			spu = spu_info[i].spu;
+			spu_mfc_sr1_set(spu, spu_info[i].saved_mfc_sr1_RW);
+			out_be32(&spu->problem->spu_runcntl_RW,
+					spu_info[i].saved_spu_runcntl_RW);
+
+			sync();
+			__delay(200);
+
+			printf("Restarted spu %.2d\n", i);
+		} else {
+			catch_memory_errors = 0;
+			printf("*** Error restarting spu %.2d\n", i);
+		}
+		catch_memory_errors = 0;
+	}
+}
+
+#define DUMP_WIDTH	23
+#define DUMP_VALUE(format, field, value)				\
+do {									\
+	if (setjmp(bus_error_jmp) == 0) {				\
+		catch_memory_errors = 1;				\
+		sync();							\
+		printf("  %-*s = "format"\n", DUMP_WIDTH,		\
+				#field, value);				\
+		sync();							\
+		__delay(200);						\
+	} else {							\
+		catch_memory_errors = 0;				\
+		printf("  %-*s = *** Error reading field.\n",		\
+					DUMP_WIDTH, #field);		\
+	}								\
+	catch_memory_errors = 0;					\
+} while (0)
+
+#define DUMP_FIELD(obj, format, field)	\
+	DUMP_VALUE(format, field, obj->field)
+
+static void dump_spu_fields(struct spu *spu)
+{
+	printf("Dumping spu fields at address %p:\n", spu);
+
+	DUMP_FIELD(spu, "0x%x", number);
+	DUMP_FIELD(spu, "%s", name);
+	DUMP_FIELD(spu, "0x%lx", local_store_phys);
+	DUMP_FIELD(spu, "0x%p", local_store);
+	DUMP_FIELD(spu, "0x%lx", ls_size);
+	DUMP_FIELD(spu, "0x%x", node);
+	DUMP_FIELD(spu, "0x%lx", flags);
+	DUMP_FIELD(spu, "%llu", class_0_pending);
+	DUMP_FIELD(spu, "0x%llx", class_0_dar);
+	DUMP_FIELD(spu, "0x%llx", class_1_dar);
+	DUMP_FIELD(spu, "0x%llx", class_1_dsisr);
+	DUMP_FIELD(spu, "0x%x", irqs[0]);
+	DUMP_FIELD(spu, "0x%x", irqs[1]);
+	DUMP_FIELD(spu, "0x%x", irqs[2]);
+	DUMP_FIELD(spu, "0x%x", slb_replace);
+	DUMP_FIELD(spu, "%d", pid);
+	DUMP_FIELD(spu, "0x%p", mm);
+	DUMP_FIELD(spu, "0x%p", ctx);
+	DUMP_FIELD(spu, "0x%p", rq);
+	DUMP_FIELD(spu, "0x%llx", timestamp);
+	DUMP_FIELD(spu, "0x%lx", problem_phys);
+	DUMP_FIELD(spu, "0x%p", problem);
+	DUMP_VALUE("0x%x", problem->spu_runcntl_RW,
+			in_be32(&spu->problem->spu_runcntl_RW));
+	DUMP_VALUE("0x%x", problem->spu_status_R,
+			in_be32(&spu->problem->spu_status_R));
+	DUMP_VALUE("0x%x", problem->spu_npc_RW,
+			in_be32(&spu->problem->spu_npc_RW));
+	DUMP_FIELD(spu, "0x%p", priv2);
+	DUMP_FIELD(spu, "0x%p", pdata);
+}
+
+static int spu_inst_dump(unsigned long adr, long count, int praddr)
+{
+	return generic_inst_dump(adr, count, praddr, print_insn_spu);
+}
+
+static void dump_spu_ls(unsigned long num, int subcmd)
+{
+	unsigned long offset, addr, ls_addr;
+
+	if (setjmp(bus_error_jmp) == 0) {
+		catch_memory_errors = 1;
+		sync();
+		ls_addr = (unsigned long)spu_info[num].spu->local_store;
+		sync();
+		__delay(200);
+	} else {
+		catch_memory_errors = 0;
+		printf("*** Error: accessing spu info for spu %ld\n", num);
+		return;
+	}
+	catch_memory_errors = 0;
+
+	if (scanhex(&offset))
+		addr = ls_addr + offset;
+	else
+		addr = spu_info[num].dump_addr;
+
+	if (addr >= ls_addr + LS_SIZE) {
+		printf("*** Error: address outside of local store\n");
+		return;
+	}
+
+	switch (subcmd) {
+	case 'i':
+		addr += spu_inst_dump(addr, 16, 1);
+		last_cmd = "sdi\n";
+		break;
+	default:
+		prdump(addr, 64);
+		addr += 64;
+		last_cmd = "sd\n";
+		break;
+	}
+
+	spu_info[num].dump_addr = addr;
+}
+
+static int do_spu_cmd(void)
+{
+	static unsigned long num = 0;
+	int cmd, subcmd = 0;
+
+	cmd = inchar();
+	switch (cmd) {
+	case 's':
+		stop_spus();
+		break;
+	case 'r':
+		restart_spus();
+		break;
+	case 'd':
+		subcmd = inchar();
+		if (isxdigit(subcmd) || subcmd == '\n')
+			termch = subcmd;
+		fallthrough;
+	case 'f':
+		scanhex(&num);
+		if (num >= XMON_NUM_SPUS || !spu_info[num].spu) {
+			printf("*** Error: invalid spu number\n");
+			return 0;
+		}
+
+		switch (cmd) {
+		case 'f':
+			dump_spu_fields(spu_info[num].spu);
+			break;
+		default:
+			dump_spu_ls(num, subcmd);
+			break;
+		}
+
+		break;
+	default:
+		return -1;
+	}
+
+	return 0;
+}
+#else /* ! CONFIG_SPU_BASE */
+static int do_spu_cmd(void)
+{
+	return -1;
+}
+#endif