85xx: Export invalidate_{i,d}cache and add flush_dcache

Added the ability for C code to invalidate the i/d-cache's and
to flush the d-cache.  This allows us to more efficient change mappings
from cache-able to cache-inhibited.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

cpu/mpc85xx/start.S

@@ -565,6 +565,7 @@ mck_return:
 
 /* Cache functions.
 */
+.globl invalidate_icache
 invalidate_icache:
 	mfspr	r0,L1CSR1
 	ori	r0,r0,L1CSR1_ICFI
@@ -574,6 +575,7 @@ invalidate_icache:
 	isync
 	blr				/* entire I cache */
 
+.globl invalidate_dcache
 invalidate_dcache:
 	mfspr	r0,L1CSR0
 	ori	r0,r0,L1CSR0_DCFI
@@ -1019,3 +1021,50 @@ unlock_ram_in_cache:
 	tlbivax	0,r3
 	isync
 	blr
+
+.globl flush_dcache
+flush_dcache:
+	mfspr	r3,SPRN_L1CFG0
+
+	rlwinm	r5,r3,9,3	/* Extract cache block size */
+	twlgti	r5,1		/* Only 32 and 64 byte cache blocks
+				 * are currently defined.
+				 */
+	li	r4,32
+	subfic	r6,r5,2		/* r6 = log2(1KiB / cache block size) -
+				 *      log2(number of ways)
+				 */
+	slw	r5,r4,r5	/* r5 = cache block size */
+
+	rlwinm	r7,r3,0,0xff	/* Extract number of KiB in the cache */
+	mulli	r7,r7,13	/* An 8-way cache will require 13
+				 * loads per set.
+				 */
+	slw	r7,r7,r6
+
+	/* save off HID0 and set DCFA */
+	mfspr	r8,SPRN_HID0
+	ori	r9,r8,HID0_DCFA@l
+	mtspr	SPRN_HID0,r9
+	isync
+
+	lis	r4,0
+	mtctr	r7
+
+1:	lwz	r3,0(r4)	/* Load... */
+	add	r4,r4,r5
+	bdnz	1b
+
+	msync
+	lis	r4,0
+	mtctr	r7
+
+1:	dcbf	0,r4		/* ...and flush. */
+	add	r4,r4,r5
+	bdnz	1b
+
+	/* restore HID0 */
+	mtspr	SPRN_HID0,r8
+	isync
+
+	blr

include/asm-ppc/cache.h

@@ -44,6 +44,7 @@ extern void clean_dcache_range(unsigned long start, unsigned long stop);
 extern void invalidate_dcache_range(unsigned long start, unsigned long stop);
 extern void flush_dcache(void);
 extern void invalidate_dcache(void);
+extern void invalidate_icache(void);
 #ifdef CONFIG_SYS_INIT_RAM_LOCK
 extern void unlock_ram_in_cache(void);
 #endif /* CONFIG_SYS_INIT_RAM_LOCK */