[MIPS] Sibyte: Replace SB1 cachecode with standard R4000 class cache code.

It may not be perfect yet but the SB1 code is badly borken and has
horrible performance issues.

Downside: This seriously breaks support for pass 1 parts of the BCM1250
where indexed cacheops don't work quite reliable but I seem to be the
last one on the planet with a pass 1 part anyway.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

2 files changed, 6 insertions, 8 deletions

diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
index 97c03865c06a..dde2adf1481c 100644
--- a/arch/mips/kernel/cpu-probe.c
+++ b/arch/mips/kernel/cpu-probe.c
@@ -746,14 +746,6 @@ static inline void cpu_probe_sibyte(struct cpuinfo_mips *c)
 {
 	decode_configs(c);
 
-	/*
-	 * For historical reasons the SB1 comes with it's own variant of
-	 * cache code which eventually will be folded into c-r4k.c.  Until
-	 * then we pretend it's got it's own cache architecture.
-	 */
-	c->options &= ~MIPS_CPU_4K_CACHE;
-	c->options |= MIPS_CPU_SB1_CACHE;
-
 	switch (c->processor_id & 0xff00) {
 	case PRID_IMP_SB1:
 		c->cputype = CPU_SB1;
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index 3d033e1cd4f0..d96f8218a91e 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -1435,6 +1435,9 @@ void __init set_handler (unsigned long offset, void *addr, unsigned long size)
 	flush_icache_range(ebase + offset, ebase + offset + size);
 }
 
+static char panic_null_cerr[] __initdata =
+	"Trying to set NULL cache error exception handler";
+
 /* Install uncached CPU exception handler */
 void __init set_uncached_handler (unsigned long offset, void *addr, unsigned long size)
 {
@@ -1445,6 +1448,9 @@ void __init set_uncached_handler (unsigned long offset, void *addr, unsigned lon
 	unsigned long uncached_ebase = TO_UNCAC(ebase);
 #endif
 
+	if (!addr)
+		panic(panic_null_cerr);
+
 	memcpy((void *)(uncached_ebase + offset), addr, size);
 }