MIPS: Netlogic: L1D cacheflush before thread enable on XLPII

On XLPII CPUs, the L1D cache has to be flushed with regular cache
operations before enabling threads in a core.

Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Signed-off-by: John Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6276/

diff --git a/arch/mips/netlogic/common/reset.S b/arch/mips/netlogic/common/reset.S
index 06381e1..57eb7a1 100644 (file)
--- a/arch/mips/netlogic/common/reset.S
+++ b/arch/mips/netlogic/common/reset.S
@@ -36,6 +36,7 @@
 
 #include <asm/asm.h>
 #include <asm/asm-offsets.h>
+#include <asm/cacheops.h>
 #include <asm/regdef.h>
 #include <asm/mipsregs.h>
 #include <asm/stackframe.h>
@@ -74,10 +75,18 @@
 .endm
 
 /*
- * Low level flush for L1D cache on XLP, the normal cache ops does
- * not do the complete and correct cache flush.
+ * L1D cache has to be flushed before enabling threads in XLP.
+ * On XLP8xx/XLP3xx, we do a low level flush using processor control
+ * registers. On XLPII CPUs, usual cache instructions work.
  */
 .macro xlp_flush_l1_dcache
+       mfc0    t0, CP0_EBASE, 0
+       andi    t0, t0, 0xff00
+       slt     t1, t0, 0x1200
+       beqz    t1, 15f
+       nop
+
+       /* XLP8xx low level cache flush */
        li      t0, LSU_DEBUG_DATA0
        li      t1, LSU_DEBUG_ADDR
        li      t2, 0           /* index */
@@ -103,6 +112,18 @@
        addi    t2, 1
        bne     t3, t2, 11b
        nop
+       b       17f
+       nop
+
+       /* XLPII CPUs, Invalidate all 64k of L1 D-cache */
+15:
+       li      t0, 0x80000000
+       li      t1, 0x80010000
+16:    cache   Index_Writeback_Inv_D, 0(t0)
+       addiu   t0, t0, 32
+       bne     t0, t1, 16b
+       nop
+17:
 .endm
 
 /*