Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-mn10300

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-mn10300:
  MN10300: gcc 4.6 vs am33 inline assembly
  MN10300: Deprecate gdbstub
  MN10300: Allow KGDB to use the MN10300 serial ports
  MN10300: Emulate single stepping in KGDB on MN10300
  MN10300: Generalise kernel debugger kernel halt, reboot or power off hook
  KGDB: Notify GDB of machine halt, reboot or power off
  MN10300: Use KGDB
  MN10300: Create generic kernel debugger hooks
  MN10300: Create general kernel debugger cache flushing
  MN10300: Introduce a general config option for kernel debugger hooks
  MN10300: The icache invalidate functions should disable the icache first
  MN10300: gdbstub: Restrict single-stepping to non-preemptable non-SMP configs

arch/mn10300/Kconfig

@@ -3,6 +3,8 @@ config MN10300
 	select HAVE_OPROFILE
 	select HAVE_GENERIC_HARDIRQS
 	select GENERIC_HARDIRQS_NO_DEPRECATED
+	select HAVE_ARCH_TRACEHOOK
+	select HAVE_ARCH_KGDB
 
 config AM33_2
 	def_bool n
@@ -401,9 +403,9 @@ comment "[!] NOTE: A lower number/level indicates a higher priority (0 is highes
 comment "____Non-maskable interrupt levels____"
 comment "The following must be set to a higher priority than local_irq_disable() and on-chip serial"
 
-config GDBSTUB_IRQ_LEVEL
+config DEBUGGER_IRQ_LEVEL
-	int "GDBSTUB interrupt priority"
+	int "DEBUGGER interrupt priority"
-	depends on GDBSTUB
+	depends on KERNEL_DEBUGGER
 	range 0 1 if LINUX_CLI_LEVEL = 2
 	range 0 2 if LINUX_CLI_LEVEL = 3
 	range 0 3 if LINUX_CLI_LEVEL = 4
@@ -437,7 +439,7 @@ config LINUX_CLI_LEVEL
 	  EPSW.IM from 7.  Any interrupt is permitted for which the level is
 	  lower than EPSW.IM.
 
-	  Certain interrupts, such as GDBSTUB and virtual MN10300 on-chip
+	  Certain interrupts, such as DEBUGGER and virtual MN10300 on-chip
 	  serial DMA interrupts are allowed to interrupt normal disabled
 	  sections.
 

arch/mn10300/Kconfig.debug

@@ -36,7 +36,7 @@ config KPROBES
 
 config GDBSTUB
 	bool "Remote GDB kernel debugging"
-	depends on DEBUG_KERNEL
+	depends on DEBUG_KERNEL && DEPRECATED
 	select DEBUG_INFO
 	select FRAME_POINTER
 	help
@@ -46,6 +46,9 @@ config GDBSTUB
 	  RAM to avoid excessive linking time. This is only useful for kernel
 	  hackers. If unsure, say N.
 
+	  This is deprecated in favour of KGDB and will be removed in a later
+	  version.
+
 config GDBSTUB_IMMEDIATE
 	bool "Break into GDB stub immediately"
 	depends on GDBSTUB
@@ -54,6 +57,14 @@ config GDBSTUB_IMMEDIATE
 	  possible, leaving the program counter at the beginning of
 	  start_kernel() in init/main.c.
 
+config GDBSTUB_ALLOW_SINGLE_STEP
+	bool "Allow software single-stepping in GDB stub"
+	depends on GDBSTUB && !SMP && !PREEMPT
+	help
+	  Allow GDB stub to perform software single-stepping through the
+	  kernel.  This doesn't work very well on SMP or preemptible kernels as
+	  it uses temporary breakpoints to emulate single-stepping.
+
 config GDB_CONSOLE
 	bool "Console output to GDB"
 	depends on GDBSTUB
@@ -142,3 +153,7 @@ config GDBSTUB_ON_TTYSx
 	default y
 
 endmenu
+
+config KERNEL_DEBUGGER
+	def_bool y
+	depends on GDBSTUB || KGDB

arch/mn10300/include/asm/debugger.h

@@ -0,0 +1,43 @@
+/* Kernel debugger for MN10300
+ *
+ * Copyright (C) 2011 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#ifndef _ASM_DEBUGGER_H
+#define _ASM_DEBUGGER_H
+
+#if defined(CONFIG_KERNEL_DEBUGGER)
+
+extern int debugger_intercept(enum exception_code, int, int, struct pt_regs *);
+extern int at_debugger_breakpoint(struct pt_regs *);
+
+#ifndef CONFIG_MN10300_DEBUGGER_CACHE_NO_FLUSH
+extern void debugger_local_cache_flushinv(void);
+extern void debugger_local_cache_flushinv_one(u8 *);
+#else
+static inline void debugger_local_cache_flushinv(void) {}
+static inline void debugger_local_cache_flushinv_one(u8 *addr) {}
+#endif
+
+#else /* CONFIG_KERNEL_DEBUGGER */
+
+static inline int debugger_intercept(enum exception_code excep,
+				     int signo, int si_code,
+				     struct pt_regs *regs)
+{
+	return 0;
+}
+
+static inline int at_debugger_breakpoint(struct pt_regs *regs)
+{
+	return 0;
+}
+
+#endif /* CONFIG_KERNEL_DEBUGGER */
+#endif /* _ASM_DEBUGGER_H */

arch/mn10300/include/asm/div64.h

@@ -15,6 +15,19 @@
 
 extern void ____unhandled_size_in_do_div___(void);
 
+/*
+ * Beginning with gcc 4.6, the MDR register is represented explicitly.  We
+ * must, therefore, at least explicitly clobber the register when we make
+ * changes to it.  The following assembly fragments *could* be rearranged in
+ * order to leave the moves to/from the MDR register to the compiler, but the
+ * gains would be minimal at best.
+ */
+#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
+# define CLOBBER_MDR_CC		"mdr", "cc"
+#else
+# define CLOBBER_MDR_CC		"cc"
+#endif
+
 /*
  * divide n by base, leaving the result in n and returning the remainder
  * - we can do this quite efficiently on the MN10300 by cascading the divides
@@ -29,7 +42,7 @@ extern void ____unhandled_size_in_do_div___(void);
 		    "mov	mdr,%1	\n"				\
 		    : "+r"(n), "=d"(__rem)				\
 		    : "r"(base), "1"(__rem)				\
-		    : "cc"						\
+		    : CLOBBER_MDR_CC					\
 		    );							\
 	} else if (sizeof(n) <= 8) {					\
 		union {							\
@@ -48,7 +61,7 @@ extern void ____unhandled_size_in_do_div___(void);
 		    : "=d"(__rem), "=r"(__quot.w[1]), "=r"(__quot.w[0])	\
 		    : "r"(base), "0"(__rem), "1"(__quot.w[1]),		\
 		      "2"(__quot.w[0])					\
-		    : "cc"						\
+		    : CLOBBER_MDR_CC					\
 		    );							\
 		n = __quot.l;						\
 	} else {							\
@@ -72,7 +85,7 @@ unsigned __muldiv64u(unsigned val, unsigned mult, unsigned div)
 					 * MDR = MDR:val%div */
 	    : "=r"(result)
 	    : "0"(val), "ir"(mult), "r"(div)
-	    : "cc"
+	    : CLOBBER_MDR_CC
 	    );
 
 	return result;
@@ -93,7 +106,7 @@ signed __muldiv64s(signed val, signed mult, signed div)
 					 * MDR = MDR:val%div */
 	    : "=r"(result)
 	    : "0"(val), "ir"(mult), "r"(div)
-	    : "cc"
+	    : CLOBBER_MDR_CC
 	    );
 
 	return result;

arch/mn10300/include/asm/fpu.h

@@ -55,7 +55,6 @@ static inline void clear_using_fpu(struct task_struct *tsk)
 
 extern asmlinkage void fpu_kill_state(struct task_struct *);
 extern asmlinkage void fpu_exception(struct pt_regs *, enum exception_code);
-extern asmlinkage void fpu_invalid_op(struct pt_regs *, enum exception_code);
 extern asmlinkage void fpu_init_state(void);
 extern asmlinkage void fpu_save(struct fpu_state_struct *);
 extern int fpu_setup_sigcontext(struct fpucontext *buf);
@@ -113,7 +112,6 @@ static inline void flush_fpu(void)
 
 extern asmlinkage
 void unexpected_fpu_exception(struct pt_regs *, enum exception_code);
-#define fpu_invalid_op unexpected_fpu_exception
 #define fpu_exception unexpected_fpu_exception
 
 struct task_struct;

arch/mn10300/include/asm/irqflags.h

@@ -20,7 +20,7 @@
 /*
  * interrupt control
  * - "disabled": run in IM1/2
- *   - level 0 - GDB stub
+ *   - level 0 - kernel debugger
  *   - level 1 - virtual serial DMA (if present)
  *   - level 5 - normal interrupt priority
  *   - level 6 - timer interrupt

arch/mn10300/include/asm/kgdb.h

@@ -0,0 +1,81 @@
+/* Kernel debugger for MN10300
+ *
+ * Copyright (C) 2010 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#ifndef _ASM_KGDB_H
+#define _ASM_KGDB_H
+
+/*
+ * BUFMAX defines the maximum number of characters in inbound/outbound
+ * buffers at least NUMREGBYTES*2 are needed for register packets
+ * Longer buffer is needed to list all threads
+ */
+#define BUFMAX			1024
+
+/*
+ * Note that this register image is in a different order than the register
+ * image that Linux produces at interrupt time.
+ */
+enum regnames {
+	GDB_FR_D0		= 0,
+	GDB_FR_D1		= 1,
+	GDB_FR_D2		= 2,
+	GDB_FR_D3		= 3,
+	GDB_FR_A0		= 4,
+	GDB_FR_A1		= 5,
+	GDB_FR_A2		= 6,
+	GDB_FR_A3		= 7,
+
+	GDB_FR_SP		= 8,
+	GDB_FR_PC		= 9,
+	GDB_FR_MDR		= 10,
+	GDB_FR_EPSW		= 11,
+	GDB_FR_LIR		= 12,
+	GDB_FR_LAR		= 13,
+	GDB_FR_MDRQ		= 14,
+
+	GDB_FR_E0		= 15,
+	GDB_FR_E1		= 16,
+	GDB_FR_E2		= 17,
+	GDB_FR_E3		= 18,
+	GDB_FR_E4		= 19,
+	GDB_FR_E5		= 20,
+	GDB_FR_E6		= 21,
+	GDB_FR_E7		= 22,
+
+	GDB_FR_SSP		= 23,
+	GDB_FR_MSP		= 24,
+	GDB_FR_USP		= 25,
+	GDB_FR_MCRH		= 26,
+	GDB_FR_MCRL		= 27,
+	GDB_FR_MCVF		= 28,
+
+	GDB_FR_FPCR		= 29,
+	GDB_FR_DUMMY0		= 30,
+	GDB_FR_DUMMY1		= 31,
+
+	GDB_FR_FS0		= 32,
+
+	GDB_FR_SIZE		= 64,
+};
+
+#define GDB_ORIG_D0		41
+#define NUMREGBYTES		(GDB_FR_SIZE*4)
+
+static inline void arch_kgdb_breakpoint(void)
+{
+	asm(".globl __arch_kgdb_breakpoint; __arch_kgdb_breakpoint: break");
+}
+extern u8 __arch_kgdb_breakpoint;
+
+#define BREAK_INSTR_SIZE	1
+#define CACHE_FLUSH_IS_SAFE	1
+
+#endif /* _ASM_KGDB_H */

arch/mn10300/include/asm/smp.h

@@ -34,7 +34,7 @@
 #define LOCAL_TIMER_IPI		193
 #define FLUSH_CACHE_IPI		194
 #define CALL_FUNCTION_NMI_IPI	195
-#define GDB_NMI_IPI		196
+#define DEBUGGER_NMI_IPI	196
 
 #define SMP_BOOT_IRQ		195
 
@@ -43,6 +43,7 @@
 #define LOCAL_TIMER_GxICR_LV	GxICR_LEVEL_4
 #define FLUSH_CACHE_GxICR_LV	GxICR_LEVEL_0
 #define SMP_BOOT_GxICR_LV	GxICR_LEVEL_0
+#define DEBUGGER_GxICR_LV	CONFIG_DEBUGGER_IRQ_LEVEL
 
 #define TIME_OUT_COUNT_BOOT_IPI	100
 #define DELAY_TIME_BOOT_IPI	75000
@@ -61,8 +62,9 @@
  * An alternate way of dealing with this could be to use the EPSW.S bits to
  * cache this information for systems with up to four CPUs.
  */
+#define arch_smp_processor_id()	(CPUID)
 #if 0
-#define raw_smp_processor_id()	(CPUID)
+#define raw_smp_processor_id()	(arch_smp_processor_id())
 #else
 #define raw_smp_processor_id()	(current_thread_info()->cpu)
 #endif

arch/mn10300/include/asm/thread_info.h

@@ -131,7 +131,11 @@ static inline unsigned long current_stack_pointer(void)
 		kmalloc_node(THREAD_SIZE, GFP_KERNEL, node)
 #endif
 
+#ifndef CONFIG_KGDB
 #define free_thread_info(ti)	kfree((ti))
+#else
+extern void free_thread_info(struct thread_info *);
+#endif
 #define get_thread_info(ti)	get_task_struct((ti)->task)
 #define put_thread_info(ti)	put_task_struct((ti)->task)
 

arch/mn10300/kernel/Makefile

@@ -21,11 +21,8 @@ obj-$(CONFIG_GDBSTUB) += gdb-stub.o gdb-low.o
 obj-$(CONFIG_GDBSTUB_ON_TTYSx) += gdb-io-serial.o gdb-io-serial-low.o
 obj-$(CONFIG_GDBSTUB_ON_TTYSMx) += gdb-io-ttysm.o gdb-io-ttysm-low.o
 
-ifeq ($(CONFIG_MN10300_CACHE_ENABLED),y)
-obj-$(CONFIG_GDBSTUB) += gdb-cache.o
-endif
-
 obj-$(CONFIG_MN10300_RTC) += rtc.o
 obj-$(CONFIG_PROFILE) += profile.o profile-low.o
 obj-$(CONFIG_MODULES) += module.o
 obj-$(CONFIG_KPROBES) += kprobes.o
+obj-$(CONFIG_KGDB) += kgdb.o

arch/mn10300/kernel/entry.S

@@ -266,7 +266,11 @@ ENTRY(raw_bus_error)
 
 ###############################################################################
 #
-# Miscellaneous exception entry points
+# NMI exception entry points
+#
+# This is used by ordinary interrupt channels that have the GxICR_NMI bit set
+# in addition to the main NMI and Watchdog channels.  SMP NMI IPIs use this
+# facility.
 #
 ###############################################################################
 ENTRY(nmi_handler)
@@ -281,7 +285,7 @@ ENTRY(nmi_handler)
 	and	NMIAGR_GN,d0
 	lsr	0x2,d0
 	cmp	CALL_FUNCTION_NMI_IPI,d0
-	bne	5f			# if not call function, jump
+	bne	nmi_not_smp_callfunc	# if not call function, jump
 
 	# function call nmi ipi
 	add	4,sp			# no need to store TBR
@@ -295,59 +299,38 @@ ENTRY(nmi_handler)
 	call	smp_nmi_call_function_interrupt[],0
 	RESTORE_ALL
 
-5:
+nmi_not_smp_callfunc:
-#ifdef CONFIG_GDBSTUB
+#ifdef CONFIG_KERNEL_DEBUGGER
-	cmp	GDB_NMI_IPI,d0
+	cmp	DEBUGGER_NMI_IPI,d0
-	bne	3f			# if not gdb nmi ipi, jump
+	bne	nmi_not_debugger	# if not kernel debugger NMI IPI, jump
 
-	# gdb nmi ipi
+	# kernel debugger NMI IPI
 	add	4,sp			# no need to store TBR
 	mov	GxICR_DETECT,d0		# clear NMI
-	movbu	d0,(GxICR(GDB_NMI_IPI))
+	movbu	d0,(GxICR(DEBUGGER_NMI_IPI))
-	movhu	(GxICR(GDB_NMI_IPI)),d0
+	movhu	(GxICR(DEBUGGER_NMI_IPI)),d0
 	and	~EPSW_NMID,epsw		# enable NMI
-#ifdef CONFIG_MN10300_CACHE_ENABLED
-	mov	(gdbstub_nmi_opr_type),d0
-	cmp	GDBSTUB_NMI_CACHE_PURGE,d0
-	bne	4f			# if not gdb cache purge, jump
 
-	# gdb cache purge nmi ipi
-	add	-20,sp
-	mov	d1,(4,sp)
-	mov	a0,(8,sp)
-	mov	a1,(12,sp)
-	mov	mdr,d0
-	mov	d0,(16,sp)
-	call	gdbstub_local_purge_cache[],0
-	mov	0x1,d0
-	mov	(CPUID),d1
-	asl	d1,d0
-	mov	gdbstub_nmi_cpumask,a0
-	bclr	d0,(a0)
-	mov	(4,sp),d1
-	mov	(8,sp),a0
-	mov	(12,sp),a1
-	mov	(16,sp),d0
-	mov	d0,mdr
-	add	20,sp
-	mov	(sp),d0
-	add	4,sp
-	rti
-4:
-#endif /* CONFIG_MN10300_CACHE_ENABLED */
-	# gdb wait nmi ipi
 	mov     (sp),d0
 	SAVE_ALL
-	call    gdbstub_nmi_wait[],0
+	mov	fp,d0			# arg 0: stacked register file
+	mov	a2,d1			# arg 1: exception number
+	call    debugger_nmi_interrupt[],0
 	RESTORE_ALL
-3:
+
-#endif /* CONFIG_GDBSTUB */
+nmi_not_debugger:
+#endif /* CONFIG_KERNEL_DEBUGGER */
 	mov     (sp),d0                 # restore TBR to d0
 	add     4,sp
 #endif /* CONFIG_SMP */
 
 	bra	__common_exception_nonmi
 
+###############################################################################
+#
+# General exception entry point
+#
+###############################################################################
 ENTRY(__common_exception)
 	add	-4,sp
 	mov	d0,(sp)

arch/mn10300/kernel/fpu.c

@@ -69,24 +69,6 @@ asmlinkage void fpu_exception(struct pt_regs *regs, enum exception_code code)
 	force_sig_info(SIGFPE, &info, tsk);
 }
 
-/*
- * handle an FPU invalid_op exception
- * - Derived from DO_EINFO() macro in arch/mn10300/kernel/traps.c
- */
-asmlinkage void fpu_invalid_op(struct pt_regs *regs, enum exception_code code)
-{
-	siginfo_t info;
-
-	if (!user_mode(regs))
-		die_if_no_fixup("FPU invalid opcode", regs, code);
-
-	info.si_signo = SIGILL;
-	info.si_errno = 0;
-	info.si_code = ILL_COPROC;
-	info.si_addr = (void *) regs->pc;
-	force_sig_info(info.si_signo, &info, current);
-}
-
 /*
  * save the FPU state to a signal context
  */

arch/mn10300/kernel/gdb-cache.S

@@ -1,105 +0,0 @@
-###############################################################################
-#
-# MN10300 Low-level cache purging routines for gdbstub
-#
-# Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
-# Written by David Howells (dhowells@redhat.com)
-#
-# This program is free software; you can redistribute it and/or
-# modify it under the terms of the GNU General Public Licence
-# as published by the Free Software Foundation; either version
-# 2 of the Licence, or (at your option) any later version.
-#
-###############################################################################
-#include <linux/sys.h>
-#include <linux/linkage.h>
-#include <asm/smp.h>
-#include <asm/cache.h>
-#include <asm/cpu-regs.h>
-#include <asm/exceptions.h>
-#include <asm/frame.inc>
-#include <asm/serial-regs.h>
-
-	.text
-
-###############################################################################
-#
-# GDB stub cache purge
-#
-###############################################################################
-	.type	gdbstub_purge_cache,@function
-ENTRY(gdbstub_purge_cache)
-	#######################################################################
-	# read the addresses tagged in the cache's tag RAM and attempt to flush
-	# those addresses specifically
-	# - we rely on the hardware to filter out invalid tag entry addresses
-	mov	DCACHE_TAG(0,0),a0		# dcache tag RAM access address
-	mov	DCACHE_PURGE(0,0),a1		# dcache purge request address
-	mov	L1_CACHE_NWAYS*L1_CACHE_NENTRIES,d1  # total number of entries
-
-mn10300_dcache_flush_loop:
-	mov	(a0),d0
-	and	L1_CACHE_TAG_ADDRESS|L1_CACHE_TAG_ENTRY,d0
-	or	L1_CACHE_TAG_VALID,d0		# retain valid entries in the
-						# cache
-	mov	d0,(a1)				# conditional purge
-
-mn10300_dcache_flush_skip:
-	add	L1_CACHE_BYTES,a0
-	add	L1_CACHE_BYTES,a1
-	add	-1,d1
-	bne	mn10300_dcache_flush_loop
-
-;; 	# unconditionally flush and invalidate the dcache
-;; 	mov	DCACHE_PURGE(0,0),a1		# dcache purge request address
-;; 	mov	L1_CACHE_NWAYS*L1_CACHE_NENTRIES,d1	# total number of
-;;							# entries
-;;
-;; gdbstub_purge_cache__dcache_loop:
-;; 	mov	(a1),d0				# unconditional purge
-;;
-;; 	add	L1_CACHE_BYTES,a1
-;; 	add	-1,d1
-;; 	bne	gdbstub_purge_cache__dcache_loop
-
-	#######################################################################
-	# now invalidate the icache
-	mov	CHCTR,a0
-	movhu	(a0),a1
-
-	mov	epsw,d1
-	and	~EPSW_IE,epsw
-	nop
-	nop
-
-	# disable the icache
-	and	~CHCTR_ICEN,d0
-	movhu	d0,(a0)
-
-	# and wait for it to calm down
-	setlb
-	movhu	(a0),d0
-	btst	CHCTR_ICBUSY,d0
-	lne
-
-	# invalidate
-	or	CHCTR_ICINV,d0
-	movhu	d0,(a0)
-
-	# wait for the cache to finish
-	mov	CHCTR,a0
-	setlb
-	movhu	(a0),d0
-	btst	CHCTR_ICBUSY,d0
-	lne
-
-	# and reenable it
-	movhu	a1,(a0)
-	movhu	(a0),d0			# read back to flush
-					# (SIGILLs all over without this)
-
-	mov	d1,epsw
-
-	ret	[],0
-
-	.size	gdbstub_purge_cache,.-gdbstub_purge_cache

arch/mn10300/kernel/gdb-io-ttysm.c

@@ -59,10 +59,10 @@ void __init gdbstub_io_init(void)
 
 	/* we want to get serial receive interrupts */
 	set_intr_level(gdbstub_port->rx_irq,
-		NUM2GxICR_LEVEL(CONFIG_GDBSTUB_IRQ_LEVEL));
+		NUM2GxICR_LEVEL(CONFIG_DEBUGGER_IRQ_LEVEL));
 	set_intr_level(gdbstub_port->tx_irq,
-		NUM2GxICR_LEVEL(CONFIG_GDBSTUB_IRQ_LEVEL));
+		NUM2GxICR_LEVEL(CONFIG_DEBUGGER_IRQ_LEVEL));
-	set_intr_stub(NUM2EXCEP_IRQ_LEVEL(CONFIG_GDBSTUB_IRQ_LEVEL),
+	set_intr_stub(NUM2EXCEP_IRQ_LEVEL(CONFIG_DEBUGGER_IRQ_LEVEL),
 		gdbstub_io_rx_handler);
 
 	*gdbstub_port->rx_icr |= GxICR_ENABLE;
@@ -88,7 +88,7 @@ void __init gdbstub_io_init(void)
 
 	/* permit level 0 IRQs only */
 	arch_local_change_intr_mask_level(
-		NUM2EPSW_IM(CONFIG_GDBSTUB_IRQ_LEVEL + 1));
+		NUM2EPSW_IM(CONFIG_DEBUGGER_IRQ_LEVEL + 1));
 }
 
 /*

arch/mn10300/kernel/gdb-stub.c

@@ -133,7 +133,7 @@
 #include <asm/system.h>
 #include <asm/gdb-stub.h>
 #include <asm/exceptions.h>
-#include <asm/cacheflush.h>
+#include <asm/debugger.h>
 #include <asm/serial-regs.h>
 #include <asm/busctl-regs.h>
 #include <unit/leds.h>
@@ -405,6 +405,7 @@ static int hexToInt(char **ptr, int *intValue)
 	return (numChars);
 }
 
+#ifdef CONFIG_GDBSTUB_ALLOW_SINGLE_STEP
 /*
  * We single-step by setting breakpoints. When an exception
  * is handled, we need to restore the instructions hoisted
@@ -729,6 +730,7 @@ static int gdbstub_single_step(struct pt_regs *regs)
 	__gdbstub_restore_bp();
 	return -EFAULT;
 }
+#endif /* CONFIG_GDBSTUB_ALLOW_SINGLE_STEP */
 
 #ifdef CONFIG_GDBSTUB_CONSOLE
 
@@ -1171,7 +1173,7 @@ int gdbstub_clear_breakpoint(u8 *addr, int len)
 
 /*
  * This function does all command processing for interfacing to gdb
- * - returns 1 if the exception should be skipped, 0 otherwise.
+ * - returns 0 if the exception should be skipped, -ERROR otherwise.
  */
 static int gdbstub(struct pt_regs *regs, enum exception_code excep)
 {
@@ -1186,7 +1188,7 @@ static int gdbstub(struct pt_regs *regs, enum exception_code excep)
 	int loop;
 
 	if (excep == EXCEP_FPU_DISABLED)
-		return 0;
+		return -ENOTSUPP;
 
 	gdbstub_flush_caches = 0;
 
@@ -1195,7 +1197,7 @@ static int gdbstub(struct pt_regs *regs, enum exception_code excep)
 	asm volatile("mov mdr,%0" : "=d"(mdr));
 	local_save_flags(epsw);
 	arch_local_change_intr_mask_level(
-		NUM2EPSW_IM(CONFIG_GDBSTUB_IRQ_LEVEL + 1));
+		NUM2EPSW_IM(CONFIG_DEBUGGER_IRQ_LEVEL + 1));
 
 	gdbstub_store_fpu();
 
@@ -1208,11 +1210,13 @@ static int gdbstub(struct pt_regs *regs, enum exception_code excep)
 	/* if we were single stepping, restore the opcodes hoisted for the
 	 * breakpoint[s] */
 	broke = 0;
+#ifdef CONFIG_GDBSTUB_ALLOW_SINGLE_STEP
 	if ((step_bp[0].addr && step_bp[0].addr == (u8 *) regs->pc) ||
 	    (step_bp[1].addr && step_bp[1].addr == (u8 *) regs->pc))
 		broke = 1;
 
 	__gdbstub_restore_bp();
+#endif
 
 	if (gdbstub_rx_unget) {
 		sigval = SIGINT;
@@ -1548,17 +1552,21 @@ packet_waiting:
 			 * Step to next instruction
 			 */
 		case 's':
-			/*
+			/* Using the T flag doesn't seem to perform single
-			 * using the T flag doesn't seem to perform single
 			 * stepping (it seems to wind up being caught by the
 			 * JTAG unit), so we have to use breakpoints and
 			 * continue instead.
 			 */
+#ifdef CONFIG_GDBSTUB_ALLOW_SINGLE_STEP
 			if (gdbstub_single_step(regs) < 0)
 				/* ignore any fault error for now */
 				gdbstub_printk("unable to set single-step"
 					       " bp\n");
 			goto done;
+#else
+			gdbstub_strcpy(output_buffer, "E01");
+			break;
+#endif
 
 			/*
 			 * Set baud rate (bBB)
@@ -1657,7 +1665,7 @@ done:
 	 * NB: We flush both caches, just to be sure...
 	 */
 	if (gdbstub_flush_caches)
-		gdbstub_purge_cache();
+		debugger_local_cache_flushinv();
 
 	gdbstub_load_fpu();
 	mn10300_set_gdbleds(0);
@@ -1667,14 +1675,23 @@ done:
 	touch_softlockup_watchdog();
 
 	local_irq_restore(epsw);
-	return 1;
+	return 0;
+}
+
+/*
+ * Determine if we hit a debugger special breakpoint that needs skipping over
+ * automatically.
+ */
+int at_debugger_breakpoint(struct pt_regs *regs)
+{
+	return 0;
 }
 
 /*
  * handle event interception
  */
-asmlinkage int gdbstub_intercept(struct pt_regs *regs,
+asmlinkage int debugger_intercept(enum exception_code excep,
-				 enum exception_code excep)
+				  int signo, int si_code, struct pt_regs *regs)
 {
 	static u8 notfirst = 1;
 	int ret;
@@ -1688,7 +1705,7 @@ asmlinkage int gdbstub_intercept(struct pt_regs *regs,
 		asm("mov mdr,%0" : "=d"(mdr));
 
 		gdbstub_entry(
-			"--> gdbstub_intercept(%p,%04x) [MDR=%lx PC=%lx]\n",
+			"--> debugger_intercept(%p,%04x) [MDR=%lx PC=%lx]\n",
 			regs, excep, mdr, regs->pc);
 
 		gdbstub_entry(
@@ -1722,7 +1739,7 @@ asmlinkage int gdbstub_intercept(struct pt_regs *regs,
 
 	ret = gdbstub(regs, excep);
 
-	gdbstub_entry("<-- gdbstub_intercept()\n");
+	gdbstub_entry("<-- debugger_intercept()\n");
 	gdbstub_busy = 0;
 	return ret;
 }

arch/mn10300/kernel/internal.h

@@ -29,6 +29,13 @@ extern void ret_from_fork(struct task_struct *) __attribute__((noreturn));
 extern void mn10300_low_ipi_handler(void);
 #endif
 
+/*
+ * smp.c
+ */
+#ifdef CONFIG_SMP
+extern void smp_jump_to_debugger(void);
+#endif
+
 /*
  * time.c
  */

arch/mn10300/kernel/irq.c

@@ -153,7 +153,7 @@ mn10300_cpupic_setaffinity(struct irq_data *d, const struct cpumask *mask,
 	case LOCAL_TIMER_IPI:
 	case FLUSH_CACHE_IPI:
 	case CALL_FUNCTION_NMI_IPI:
-	case GDB_NMI_IPI:
+	case DEBUGGER_NMI_IPI:
 #ifdef CONFIG_MN10300_TTYSM0
 	case SC0RXIRQ:
 	case SC0TXIRQ:

arch/mn10300/kernel/mn10300-serial.c

@@ -119,6 +119,10 @@ static int mn10300_serial_request_port(struct uart_port *);
 static void mn10300_serial_config_port(struct uart_port *, int);
 static int mn10300_serial_verify_port(struct uart_port *,
 					struct serial_struct *);
+#ifdef CONFIG_CONSOLE_POLL
+static void mn10300_serial_poll_put_char(struct uart_port *, unsigned char);
+static int mn10300_serial_poll_get_char(struct uart_port *);
+#endif
 
 static const struct uart_ops mn10300_serial_ops = {
 	.tx_empty	= mn10300_serial_tx_empty,
@@ -138,6 +142,10 @@ static const struct uart_ops mn10300_serial_ops = {
 	.request_port	= mn10300_serial_request_port,
 	.config_port	= mn10300_serial_config_port,
 	.verify_port	= mn10300_serial_verify_port,
+#ifdef CONFIG_CONSOLE_POLL
+	.poll_put_char	= mn10300_serial_poll_put_char,
+	.poll_get_char	= mn10300_serial_poll_get_char,
+#endif
 };
 
 static irqreturn_t mn10300_serial_interrupt(int irq, void *dev_id);
@@ -1634,3 +1642,70 @@ static int __init mn10300_serial_console_init(void)
 
 console_initcall(mn10300_serial_console_init);
 #endif
+
+#ifdef CONFIG_CONSOLE_POLL
+/*
+ * Polled character reception for the kernel debugger
+ */
+static int mn10300_serial_poll_get_char(struct uart_port *_port)
+{
+	struct mn10300_serial_port *port =
+		container_of(_port, struct mn10300_serial_port, uart);
+	unsigned ix;
+	u8 st, ch;
+
+	_enter("%s", port->name);
+
+	do {
+		/* pull chars out of the hat */
+		ix = port->rx_outp;
+		if (ix == port->rx_inp)
+			return NO_POLL_CHAR;
+
+		ch = port->rx_buffer[ix++];
+		st = port->rx_buffer[ix++];
+		smp_rmb();
+		port->rx_outp = ix & (MNSC_BUFFER_SIZE - 1);
+
+	} while (st & (SC01STR_FEF | SC01STR_PEF | SC01STR_OEF));
+
+	return ch;
+}
+
+
+/*
+ * Polled character transmission for the kernel debugger
+ */
+static void mn10300_serial_poll_put_char(struct uart_port *_port,
+					 unsigned char ch)
+{
+	struct mn10300_serial_port *port =
+		container_of(_port, struct mn10300_serial_port, uart);
+	u8 intr, tmp;
+
+	/* wait for the transmitter to finish anything it might be doing (and
+	 * this includes the virtual DMA handler, so it might take a while) */
+	while (*port->_status & (SC01STR_TBF | SC01STR_TXF))
+		continue;
+
+	/* disable the Tx ready interrupt */
+	intr = *port->_intr;
+	*port->_intr = intr & ~SC01ICR_TI;
+	tmp = *port->_intr;
+
+	if (ch == 0x0a) {
+		*(u8 *) port->_txb = 0x0d;
+		while (*port->_status & SC01STR_TBF)
+			continue;
+	}
+
+	*(u8 *) port->_txb = ch;
+	while (*port->_status & SC01STR_TBF)
+		continue;
+
+	/* restore the Tx interrupt flag */
+	*port->_intr = intr;
+	tmp = *port->_intr;
+}
+
+#endif /* CONFIG_CONSOLE_POLL */

arch/mn10300/kernel/process.c

@@ -135,7 +135,7 @@ void release_segments(struct mm_struct *mm)
 
 void machine_restart(char *cmd)
 {
-#ifdef CONFIG_GDBSTUB
+#ifdef CONFIG_KERNEL_DEBUGGER
 	gdbstub_exit(0);
 #endif
 
@@ -148,14 +148,14 @@ void machine_restart(char *cmd)
 
 void machine_halt(void)
 {
-#ifdef CONFIG_GDBSTUB
+#ifdef CONFIG_KERNEL_DEBUGGER
 	gdbstub_exit(0);
 #endif
 }
 
 void machine_power_off(void)
 {
-#ifdef CONFIG_GDBSTUB
+#ifdef CONFIG_KERNEL_DEBUGGER
 	gdbstub_exit(0);
 #endif
 }