[MIPS] Initialize S-cache function pointers even on S-cache-less CPUs.

    
When a CPU has no scache, the scache flushing functions currently
aren't getting initialized and the NULL pointer is eventually called
as a function.  Initialize the scache flushing functions as a noop
when there's no scache.
    
Initial patch by me and most of the debugging done by Martin Michlmayr.
    
Signed-off-by: Martin Michlmayr <tbm@cyrius.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 11 insertions, 5 deletions

diff --git a/arch/mips/mm/c-r4k.c b/arch/mips/mm/c-r4k.c
index 1b71d91e8268..0668e9bfce41 100644
--- a/arch/mips/mm/c-r4k.c
+++ b/arch/mips/mm/c-r4k.c
@@ -235,7 +235,9 @@ static inline void r4k_blast_scache_page_setup(void)
 {
         unsigned long sc_lsize = cpu_scache_line_size();
 
-        if (sc_lsize == 16)
+        if (scache_size == 0)
+                r4k_blast_scache_page = (void *)no_sc_noop;
+        else if (sc_lsize == 16)
                 r4k_blast_scache_page = blast_scache16_page;
         else if (sc_lsize == 32)
                 r4k_blast_scache_page = blast_scache32_page;
@@ -251,7 +253,9 @@ static inline void r4k_blast_scache_page_indexed_setup(void)
 {
         unsigned long sc_lsize = cpu_scache_line_size();
 
-        if (sc_lsize == 16)
+        if (scache_size == 0)
+                r4k_blast_scache_page_indexed = (void *)no_sc_noop;
+        else if (sc_lsize == 16)
                 r4k_blast_scache_page_indexed = blast_scache16_page_indexed;
         else if (sc_lsize == 32)
                 r4k_blast_scache_page_indexed = blast_scache32_page_indexed;
@@ -267,7 +271,9 @@ static inline void r4k_blast_scache_setup(void)
 {
         unsigned long sc_lsize = cpu_scache_line_size();
 
-        if (sc_lsize == 16)
+        if (scache_size == 0)
+                r4k_blast_scache = (void *)no_sc_noop;
+        else if (sc_lsize == 16)
                 r4k_blast_scache = blast_scache16;
         else if (sc_lsize == 32)
                 r4k_blast_scache = blast_scache32;
@@ -482,7 +488,7 @@ static inline void local_r4k_flush_icache_range(void *args)
                         protected_blast_dcache_range(start, end);
                 }
 
-                if (!cpu_icache_snoops_remote_store) {
+                if (!cpu_icache_snoops_remote_store && scache_size) {
                         if (end - start > scache_size)
                                 r4k_blast_scache();
                         else
@@ -651,7 +657,7 @@ static void local_r4k_flush_cache_sigtramp(void * arg)
 
         R4600_HIT_CACHEOP_WAR_IMPL;
         protected_writeback_dcache_line(addr & ~(dc_lsize - 1));
-        if (!cpu_icache_snoops_remote_store)
+        if (!cpu_icache_snoops_remote_store && scache_size)
                 protected_writeback_scache_line(addr & ~(sc_lsize - 1));
         protected_flush_icache_line(addr & ~(ic_lsize - 1));
         if (MIPS4K_ICACHE_REFILL_WAR) {