microblaze: Flush caches before enabling them

Flushing caches is necessary because of soft reset
which doesn't clear caches.

Signed-off-by: Michal Simek <monstr@monstr.eu>
Reviewed-by: Marek Vasut <marex@denx.de>

arch/microblaze/cpu/cache.c

@@ -61,12 +61,7 @@ void	dcache_enable (void) {
 
 void	dcache_disable(void) {
 #ifdef XILINX_USE_DCACHE
-#ifdef XILINX_DCACHE_BYTE_SIZE
 	flush_cache(0, XILINX_DCACHE_BYTE_SIZE);
-#else
-#warning please rebuild BSPs and update configuration
-	flush_cache(0, 32768);
-#endif
 #endif
 	MSRCLR(0x80);
 }

arch/microblaze/cpu/start.S

@@ -132,6 +132,12 @@ _start:
 	rsubi	r8, r10, 0x26
 	sh	r6, r0, r8
 
+	/* Flush cache before enable cache */
+	addik	r5, r0, 0
+	addik	r6, r0, XILINX_DCACHE_BYTE_SIZE
+flush:	bralid r15, flush_cache
+	nop
+
 	/* enable instruction and data cache */
 	mfs	r12, rmsr
 	ori	r12, r12, 0xa0

arch/microblaze/lib/bootm.c

@@ -70,12 +70,7 @@ int do_bootm_linux(int flag, int argc, char * const argv[], bootm_headers_t *ima
 #endif
 
 #ifdef XILINX_USE_DCACHE
-#ifdef XILINX_DCACHE_BYTE_SIZE
 	flush_cache(0, XILINX_DCACHE_BYTE_SIZE);
-#else
-#warning please rebuild BSPs and update configuration
-	flush_cache(0, 32768);
-#endif
 #endif
 	/*
 	 * Linux Kernel Parameters (passing device tree):

include/configs/microblaze-generic.h

@@ -287,6 +287,10 @@
 # undef CONFIG_DCACHE
 #endif
 
+#ifndef XILINX_DCACHE_BYTE_SIZE
+#define XILINX_DCACHE_BYTE_SIZE	32768
+#endif
+
 /*
  * BOOTP options
  */