powerpc/p4080: Add workaround for erratum CPU22

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

arch/powerpc/cpu/mpc85xx/cmd_errata.c

@@ -44,7 +44,9 @@ static int do_errata(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 #if defined(CONFIG_SYS_P4080_ERRATUM_SERDES8)
 	puts("Work-around for Erratum SERDES8 enabled\n");
 #endif
-
+#if defined(CONFIG_SYS_P4080_ERRATUM_CPU22)
+	puts("Work-around for Erratum CPU22 enabled\n");
+#endif
 	return 0;
 }
 

arch/powerpc/cpu/mpc85xx/cpu_init.c

@@ -32,6 +32,7 @@
 #include <ioports.h>
 #include <sata.h>
 #include <asm/io.h>
+#include <asm/cache.h>
 #include <asm/mmu.h>
 #include <asm/fsl_law.h>
 #include <asm/fsl_serdes.h>
@@ -245,6 +246,12 @@ int cpu_init_r(void)
 	volatile fsl_lbc_t *lbc = LBC_BASE_ADDR;
 #endif
 
+#if defined(CONFIG_SYS_P4080_ERRATUM_CPU22)
+	flush_dcache();
+	mtspr(L1CSR2, (mfspr(L1CSR2) | L1CSR2_DCWS));
+	sync();
+#endif
+
 	puts ("L2:    ");
 
 #if defined(CONFIG_L2_CACHE)

arch/powerpc/cpu/mpc85xx/release.S

@@ -136,6 +136,12 @@ __secondary_start_page:
 	mtspr	L1CSR2,r8
 #endif
 
+#if defined(CONFIG_SYS_P4080_ERRATUM_CPU22)
+	mfspr	r8,L1CSR2
+	oris	r8,r8,(L1CSR2_DCWS)@h
+	mtspr	L1CSR2,r8
+#endif
+
 #ifdef CONFIG_BACKSIDE_L2_CACHE
 	/* Enable/invalidate the L2 cache */
 	msync

arch/powerpc/include/asm/processor.h

@@ -495,6 +495,7 @@
 #define   L1CSR1_ICFI		0x00000002	/* Instruction Cache Flash Invalidate */
 #define   L1CSR1_ICE		0x00000001	/* Instruction Cache Enable */
 #define SPRN_L1CSR2	0x25e	/* L1 Data Cache Control and Status Register 2 */
+#define   L1CSR2_DCWS		0x40000000	/* Data Cache Write Shadow */
 #define SPRN_L2CSR0	0x3f9	/* L2 Data Cache Control and Status Register 0 */
 #define   L2CSR0_L2E		0x80000000	/* L2 Cache Enable */
 #define   L2CSR0_L2PE		0x40000000	/* L2 Cache Parity/ECC Enable */