sh: nommu: Support building without an uncached mapping.
Now that nommu selects 32BIT we run in to the situation where SH-2A
supports an uncached identity mapping by way of the BSC, while the SH-2
does not. This provides stubs for the PC manglers and tidies up some of
the system*.h mess in the process.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/include/asm/uncached.h b/arch/sh/include/asm/uncached.h
index e3419f9..6f8816b 100644
--- a/arch/sh/include/asm/uncached.h
+++ b/arch/sh/include/asm/uncached.h
@@ -4,15 +4,55 @@
#include <linux/bug.h>
#ifdef CONFIG_UNCACHED_MAPPING
+extern unsigned long cached_to_uncached;
+extern unsigned long uncached_size;
extern unsigned long uncached_start, uncached_end;
extern int virt_addr_uncached(unsigned long kaddr);
extern void uncached_init(void);
extern void uncached_resize(unsigned long size);
+
+/*
+ * Jump to uncached area.
+ * When handling TLB or caches, we need to do it from an uncached area.
+ */
+#define jump_to_uncached() \
+do { \
+ unsigned long __dummy; \
+ \
+ __asm__ __volatile__( \
+ "mova 1f, %0\n\t" \
+ "add %1, %0\n\t" \
+ "jmp @%0\n\t" \
+ " nop\n\t" \
+ ".balign 4\n" \
+ "1:" \
+ : "=&z" (__dummy) \
+ : "r" (cached_to_uncached)); \
+} while (0)
+
+/*
+ * Back to cached area.
+ */
+#define back_to_cached() \
+do { \
+ unsigned long __dummy; \
+ ctrl_barrier(); \
+ __asm__ __volatile__( \
+ "mov.l 1f, %0\n\t" \
+ "jmp @%0\n\t" \
+ " nop\n\t" \
+ ".balign 4\n" \
+ "1: .long 2f\n" \
+ "2:" \
+ : "=&r" (__dummy)); \
+} while (0)
#else
#define virt_addr_uncached(kaddr) (0)
#define uncached_init() do { } while (0)
#define uncached_resize(size) BUG()
+#define jump_to_uncached() do { } while (0)
+#define back_to_cached() do { } while (0)
#endif
#endif /* __ASM_SH_UNCACHED_H */