MN10300: Create general kernel debugger cache flushing

Create general kernel debugger cache flushing for MN10300 and get rid of the
old stuff that gdbstub was using.

Signed-off-by: David Howells <dhowells@redhat.com>

arch/mn10300/include/asm/debugger.h

@@ -14,6 +14,14 @@
 
 #if defined(CONFIG_KERNEL_DEBUGGER)
 
+#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 */
 
 #endif /* CONFIG_KERNEL_DEBUGGER */

arch/mn10300/kernel/Makefile

@@ -21,10 +21,6 @@ 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

arch/mn10300/kernel/entry.S

@@ -306,36 +306,7 @@ ENTRY(nmi_handler)
 	movbu	d0,(GxICR(GDB_NMI_IPI))
 	movhu	(GxICR(GDB_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

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>
@@ -1665,7 +1665,7 @@ static int gdbstub(struct pt_regs *regs, enum exception_code excep)
 	 * 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);

arch/mn10300/mm/Kconfig.cache

@@ -99,3 +99,49 @@ config MN10300_CACHE_INV_ICACHE
 	help
 	  Set if we need the icache to be invalidated, even if the dcache is in
 	  write-through mode and doesn't need flushing.
+
+#
+# The kernel debugger gets its own separate cache flushing functions
+#
+config MN10300_DEBUGGER_CACHE_FLUSH_BY_TAG
+	def_bool y if KERNEL_DEBUGGER && \
+			MN10300_CACHE_WBACK && \
+			!MN10300_CACHE_SNOOP && \
+			MN10300_CACHE_MANAGE_BY_TAG
+	help
+	  Set if the debugger needs to flush the dcache and invalidate the
+	  icache using the cache tag registers to make breakpoints work.
+
+config MN10300_DEBUGGER_CACHE_FLUSH_BY_REG
+	def_bool y if KERNEL_DEBUGGER && \
+			MN10300_CACHE_WBACK && \
+			!MN10300_CACHE_SNOOP && \
+			MN10300_CACHE_MANAGE_BY_REG
+	help
+	  Set if the debugger needs to flush the dcache and invalidate the
+	  icache using automatic purge registers to make breakpoints work.
+
+config MN10300_DEBUGGER_CACHE_INV_BY_TAG
+	def_bool y if KERNEL_DEBUGGER && \
+			MN10300_CACHE_WTHRU && \
+			!MN10300_CACHE_SNOOP && \
+			MN10300_CACHE_MANAGE_BY_TAG
+	help
+	  Set if the debugger needs to invalidate the icache using the cache
+	  tag registers to make breakpoints work.
+
+config MN10300_DEBUGGER_CACHE_INV_BY_REG
+	def_bool y if KERNEL_DEBUGGER && \
+			MN10300_CACHE_WTHRU && \
+			!MN10300_CACHE_SNOOP && \
+			MN10300_CACHE_MANAGE_BY_REG
+	help
+	  Set if the debugger needs to invalidate the icache using automatic
+	  purge registers to make breakpoints work.
+
+config MN10300_DEBUGGER_CACHE_NO_FLUSH
+	def_bool y if KERNEL_DEBUGGER && \
+			(MN10300_CACHE_DISABLED || MN10300_CACHE_SNOOP)
+	help
+	  Set if the debugger does not need to flush the dcache and/or
+	  invalidate the icache to make breakpoints work.

arch/mn10300/mm/Makefile

@@ -13,6 +13,15 @@ cacheflush-$(CONFIG_MN10300_CACHE_INV_BY_REG) += cache-inv-by-reg.o
 cacheflush-$(CONFIG_MN10300_CACHE_FLUSH_BY_TAG) += cache-flush-by-tag.o
 cacheflush-$(CONFIG_MN10300_CACHE_FLUSH_BY_REG) += cache-flush-by-reg.o
 
+cacheflush-$(CONFIG_MN10300_DEBUGGER_CACHE_FLUSH_BY_TAG) += \
+	cache-dbg-flush-by-tag.o cache-dbg-inv-by-tag.o
+cacheflush-$(CONFIG_MN10300_DEBUGGER_CACHE_FLUSH_BY_REG) += \
+	cache-dbg-flush-by-reg.o
+cacheflush-$(CONFIG_MN10300_DEBUGGER_CACHE_INV_BY_TAG) += \
+	cache-dbg-inv-by-tag.o cache-dbg-inv.o
+cacheflush-$(CONFIG_MN10300_DEBUGGER_CACHE_INV_BY_REG) += \
+	cache-dbg-inv-by-reg.o cache-dbg-inv.o
+
 cacheflush-$(CONFIG_MN10300_CACHE_DISABLED) := cache-disabled.o
 
 obj-y := \