csky: Support dynamic start physical address

Before this patch csky-linux need CONFIG_RAM_BASE to determine start
physical address. Now we use phys_offset variable to replace the macro
of PHYS_OFFSET and we setup phys_offset with real physical address which
is determined during startup in head.S.

With this patch we needn't re-compile kernel for different start
physical address. ie: 0x0 / 0xc0000000 start physical address could use
the same vmlinux, be care different start address must be 512MB aligned.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>

1 files changed, 20 insertions, 0 deletions

diff --git a/arch/csky/abiv2/inc/abi/ckmmu.h b/arch/csky/abiv2/inc/abi/ckmmu.h
index 97230ad9427c..31d75e1a724a 100644
--- a/arch/csky/abiv2/inc/abi/ckmmu.h
+++ b/arch/csky/abiv2/inc/abi/ckmmu.h
@@ -42,6 +42,26 @@ static inline void write_mmu_entryhi(int value)
 	mtcr("cr<4, 15>", value);
 }
 
+static inline unsigned long read_mmu_msa0(void)
+{
+	return mfcr("cr<30, 15>");
+}
+
+static inline void write_mmu_msa0(unsigned long value)
+{
+	mtcr("cr<30, 15>", value);
+}
+
+static inline unsigned long read_mmu_msa1(void)
+{
+	return mfcr("cr<31, 15>");
+}
+
+static inline void write_mmu_msa1(unsigned long value)
+{
+	mtcr("cr<31, 15>", value);
+}
+
 /*
  * TLB operations.
  */