powerpc: Merge xmon

The merged version follows the ppc64 version pretty closely mostly,
and in fact ARCH=ppc64 now uses the arch/powerpc/xmon version.
The main difference for ppc64 is that the 'p' command to call
show_state (which was always pretty dodgy) has been replaced by
the ppc32 'p' command, which calls a given procedure (so in fact
the old 'p' command behaviour can be achieved with 'p $show_state').

Signed-off-by: Paul Mackerras <paulus@samba.org>

arch/powerpc/Makefile

@@ -131,7 +131,7 @@ core-y				+= arch/powerpc/kernel/ \
 				   arch/powerpc/sysdev/ \
 				   arch/powerpc/platforms/
 core-$(CONFIG_MATH_EMULATION)	+= arch/ppc/math-emu/
-#core-$(CONFIG_XMON)		+= arch/powerpc/xmon/
+core-$(CONFIG_XMON)		+= arch/powerpc/xmon/
 core-$(CONFIG_APUS)		+= arch/ppc/amiga/
 drivers-$(CONFIG_8xx)		+= arch/ppc/8xx_io/
 drivers-$(CONFIG_4xx)		+= arch/ppc/4xx_io/

arch/powerpc/kernel/head_32.S

@@ -271,6 +271,9 @@ __secondary_hold_acknowledge:
 	li	r10,MSR_KERNEL & ~(MSR_IR|MSR_DR); /* can take exceptions */ \
 	MTMSRD(r10);			/* (except for mach check in rtas) */ \
 	stw	r0,GPR0(r11);	\
+	lis	r10,0x7265;		/* put exception frame marker */ \
+	addi	r10,r10,0x6773;	\
+	stw	r10,8(r11);	\
 	SAVE_4GPRS(3, r11);	\
 	SAVE_2GPRS(7, r11)
 

arch/powerpc/kernel/ppc_ksyms.c

@@ -44,7 +44,6 @@
 #include <asm/cputable.h>
 #include <asm/btext.h>
 #include <asm/div64.h>
-#include <asm/xmon.h>
 
 #ifdef  CONFIG_8xx
 #include <asm/commproc.h>
@@ -238,10 +237,6 @@ EXPORT_SYMBOL(console_drivers);
 EXPORT_SYMBOL(cacheable_memcpy);
 #endif
 
-#ifdef CONFIG_XMON
-EXPORT_SYMBOL(xmon);
-EXPORT_SYMBOL(xmon_printf);
-#endif
 EXPORT_SYMBOL(__up);
 EXPORT_SYMBOL(__down);
 EXPORT_SYMBOL(__down_interruptible);

arch/powerpc/kernel/setup_32.c

@@ -302,8 +302,10 @@ void __init setup_arch(char **cmdline_p)
 
 #ifdef CONFIG_XMON
 	xmon_map_scc();
-	if (strstr(cmd_line, "xmon"))
-		xmon(NULL);
+	if (strstr(cmd_line, "xmon")) {
+		xmon_init(1);
+		debugger(NULL);
+	}
 #endif /* CONFIG_XMON */
 	if ( ppc_md.progress ) ppc_md.progress("setup_arch: enter", 0x3eab);
 

arch/powerpc/kernel/setup_64.c

@@ -59,6 +59,7 @@
 #include <asm/iSeries/ItLpNaca.h>
 #include <asm/firmware.h>
 #include <asm/systemcfg.h>
+#include <asm/xmon.h>
 
 #ifdef DEBUG
 #define DBG(fmt...) udbg_printf(fmt)

arch/powerpc/lib/Makefile

@@ -11,6 +11,8 @@ obj-$(CONFIG_PPC32)	+= div64.o copy_32.o checksum_32.o
 obj-$(CONFIG_PPC64)	+= checksum_64.o copypage_64.o copyuser_64.o \
 			   memcpy_64.o usercopy_64.o mem_64.o
 obj-$(CONFIG_PPC_ISERIES) += e2a.o
+obj-$(CONFIG_XMON)	+= sstep.o
+
 ifeq ($(CONFIG_PPC64),y)
 obj-$(CONFIG_SMP)	+= locks.o
 obj-$(CONFIG_DEBUG_KERNEL) += sstep.o

arch/powerpc/xmon/Makefile

@@ -0,0 +1,11 @@
+# Makefile for xmon
+
+ifdef CONFIG_PPC64
+EXTRA_CFLAGS += -mno-minimal-toc
+endif
+
+obj-$(CONFIG_8xx)	+= start_8xx.o
+obj-$(CONFIG_6xx)	+= start_32.o
+obj-$(CONFIG_4xx)	+= start_32.o
+obj-$(CONFIG_PPC64)	+= start_64.o
+obj-y			+= xmon.o ppc-dis.o ppc-opc.o subr_prf.o setjmp.o

arch/powerpc/xmon/setjmp.S

@@ -0,0 +1,135 @@
+/*
+ * Copyright (C) 1996 Paul Mackerras.
+ *
+ *      This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ *
+ * NOTE: assert(sizeof(buf) > 23 * sizeof(long))
+ */
+#include <asm/processor.h>
+#include <asm/ppc_asm.h>
+#include <asm/asm-offsets.h>
+
+_GLOBAL(xmon_setjmp)
+	mflr	r0
+	STL	r0,0(r3)
+	STL	r1,SZL(r3)
+	STL	r2,2*SZL(r3)
+	mfcr	r0
+	STL	r0,3*SZL(r3)
+	STL	r13,4*SZL(r3)
+	STL	r14,5*SZL(r3)
+	STL	r15,6*SZL(r3)
+	STL	r16,7*SZL(r3)
+	STL	r17,8*SZL(r3)
+	STL	r18,9*SZL(r3)
+	STL	r19,10*SZL(r3)
+	STL	r20,11*SZL(r3)
+	STL	r21,12*SZL(r3)
+	STL	r22,13*SZL(r3)
+	STL	r23,14*SZL(r3)
+	STL	r24,15*SZL(r3)
+	STL	r25,16*SZL(r3)
+	STL	r26,17*SZL(r3)
+	STL	r27,18*SZL(r3)
+	STL	r28,19*SZL(r3)
+	STL	r29,20*SZL(r3)
+	STL	r30,21*SZL(r3)
+	STL	r31,22*SZL(r3)
+	li	r3,0
+	blr
+
+_GLOBAL(xmon_longjmp)
+	CMPI	r4,0
+	bne	1f
+	li	r4,1
+1:	LDL	r13,4*SZL(r3)
+	LDL	r14,5*SZL(r3)
+	LDL	r15,6*SZL(r3)
+	LDL	r16,7*SZL(r3)
+	LDL	r17,8*SZL(r3)
+	LDL	r18,9*SZL(r3)
+	LDL	r19,10*SZL(r3)
+	LDL	r20,11*SZL(r3)
+	LDL	r21,12*SZL(r3)
+	LDL	r22,13*SZL(r3)
+	LDL	r23,14*SZL(r3)
+	LDL	r24,15*SZL(r3)
+	LDL	r25,16*SZL(r3)
+	LDL	r26,17*SZL(r3)
+	LDL	r27,18*SZL(r3)
+	LDL	r28,19*SZL(r3)
+	LDL	r29,20*SZL(r3)
+	LDL	r30,21*SZL(r3)
+	LDL	r31,22*SZL(r3)
+	LDL	r0,3*SZL(r3)
+	mtcrf	0x38,r0
+	LDL	r0,0(r3)
+	LDL	r1,SZL(r3)
+	LDL	r2,2*SZL(r3)
+	mtlr	r0
+	mr	r3,r4
+	blr
+
+/*
+ * Grab the register values as they are now.
+ * This won't do a particularily good job because we really
+ * want our caller's caller's registers, and our caller has
+ * already executed its prologue.
+ * ToDo: We could reach back into the caller's save area to do
+ * a better job of representing the caller's state (note that
+ * that will be different for 32-bit and 64-bit, because of the
+ * different ABIs, though).
+ */
+_GLOBAL(xmon_save_regs)
+	STL	r0,0*SZL(r3)
+	STL	r2,2*SZL(r3)
+	STL	r3,3*SZL(r3)
+	STL	r4,4*SZL(r3)
+	STL	r5,5*SZL(r3)
+	STL	r6,6*SZL(r3)
+	STL	r7,7*SZL(r3)
+	STL	r8,8*SZL(r3)
+	STL	r9,9*SZL(r3)
+	STL	r10,10*SZL(r3)
+	STL	r11,11*SZL(r3)
+	STL	r12,12*SZL(r3)
+	STL	r13,13*SZL(r3)
+	STL	r14,14*SZL(r3)
+	STL	r15,15*SZL(r3)
+	STL	r16,16*SZL(r3)
+	STL	r17,17*SZL(r3)
+	STL	r18,18*SZL(r3)
+	STL	r19,19*SZL(r3)
+	STL	r20,20*SZL(r3)
+	STL	r21,21*SZL(r3)
+	STL	r22,22*SZL(r3)
+	STL	r23,23*SZL(r3)
+	STL	r24,24*SZL(r3)
+	STL	r25,25*SZL(r3)
+	STL	r26,26*SZL(r3)
+	STL	r27,27*SZL(r3)
+	STL	r28,28*SZL(r3)
+	STL	r29,29*SZL(r3)
+	STL	r30,30*SZL(r3)
+	STL	r31,31*SZL(r3)
+	/* go up one stack frame for SP */
+	LDL	r4,0(r1)
+	STL	r4,1*SZL(r3)
+	/* get caller's LR */
+	LDL	r0,LRSAVE(r4)
+	STL	r0,_NIP-STACK_FRAME_OVERHEAD(r3)
+	STL	r0,_LINK-STACK_FRAME_OVERHEAD(r3)
+	mfmsr	r0
+	STL	r0,_MSR-STACK_FRAME_OVERHEAD(r3)
+	mfctr	r0
+	STL	r0,_CTR-STACK_FRAME_OVERHEAD(r3)
+	mfxer	r0
+	STL	r0,_XER-STACK_FRAME_OVERHEAD(r3)
+	mfcr	r0
+	STL	r0,_CCR-STACK_FRAME_OVERHEAD(r3)
+	li	r0,0
+	STL	r0,_TRAP-STACK_FRAME_OVERHEAD(r3)
+	blr