sh: Support explicit L1 cache disabling.
This reworks the cache mode configuration in Kconfig, and allows for
explicit selection of write-back/write-through/off configurations.
All of the cache flushing routines are optimized away for the off
case.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/kernel/cpu/init.c b/arch/sh/kernel/cpu/init.c
index 9172e97..fdc245b 100644
--- a/arch/sh/kernel/cpu/init.c
+++ b/arch/sh/kernel/cpu/init.c
@@ -143,12 +143,15 @@
flags &= ~CCR_CACHE_EMODE;
#endif
-#ifdef CONFIG_SH_WRITETHROUGH
- /* Turn on Write-through caching */
+#if defined(CONFIG_CACHE_WRITETHROUGH)
+ /* Write-through */
flags |= CCR_CACHE_WT;
-#else
- /* .. or default to Write-back */
+#elif defined(CONFIG_CACHE_WRITEBACK)
+ /* Write-back */
flags |= CCR_CACHE_CB;
+#else
+ /* Off */
+ flags &= ~CCR_CACHE_ENABLE;
#endif
ctrl_outl(flags, CCR);
diff --git a/arch/sh/kernel/sh_ksyms.c b/arch/sh/kernel/sh_ksyms.c
index 37aef0a..de25070 100644
--- a/arch/sh/kernel/sh_ksyms.c
+++ b/arch/sh/kernel/sh_ksyms.c
@@ -128,7 +128,8 @@
#endif /* __GNUC__ == 4 */
#endif
-#if defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB)
+#if !defined(CONFIG_CACHE_OFF) && (defined(CONFIG_CPU_SH4) || \
+ defined(CONFIG_SH7705_CACHE_32KB))
/* needed by some modules */
EXPORT_SYMBOL(flush_cache_all);
EXPORT_SYMBOL(flush_cache_range);
@@ -136,8 +137,8 @@
EXPORT_SYMBOL(__flush_purge_region);
#endif
-#if defined(CONFIG_MMU) && (defined(CONFIG_CPU_SH4) || \
- defined(CONFIG_SH7705_CACHE_32KB))
+#if !defined(CONFIG_CACHE_OFF) && defined(CONFIG_MMU) && \
+ (defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB))
EXPORT_SYMBOL(clear_user_page);
#endif