[U-Boot] [PATCH 7/9] ColdFire:Add mb for 5253 dram initialization

Jason Jin Jason.jin at freescale.com
Tue Apr 19 08:15:32 CEST 2011


The dram initialization sequence should be in order.
This patch add mb for the dram intialization code to make
sure the compiler do not disorder the code.

Signed-off-by: Jason Jin <Jason.jin at freescale.com>
---
 arch/m68k/include/asm/io.h            |    2 ++
 board/freescale/m5253demo/m5253demo.c |    4 ++++
 2 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/arch/m68k/include/asm/io.h b/arch/m68k/include/asm/io.h
index 531f420..d86eaf9 100644
--- a/arch/m68k/include/asm/io.h
+++ b/arch/m68k/include/asm/io.h
@@ -81,6 +81,8 @@
 #define outl(val, port)		out_le32((u32 *)((port)+_IO_BASE), (val))
 #endif
 
+#define mb() __asm__ __volatile__ ("" : : : "memory")
+
 extern inline void _insb(volatile u8 * port, void *buf, int ns)
 {
 	u8 *data = (u8 *) buf;
diff --git a/board/freescale/m5253demo/m5253demo.c b/board/freescale/m5253demo/m5253demo.c
index 4772074..8ffb2cc 100644
--- a/board/freescale/m5253demo/m5253demo.c
+++ b/board/freescale/m5253demo/m5253demo.c
@@ -27,6 +27,7 @@
 #include <common.h>
 #include <asm/immap.h>
 #include <netdev.h>
+#include <asm/io.h>
 
 int checkboard(void)
 {
@@ -63,10 +64,12 @@ phys_size_t initdram(int board_type)
 		__asm__("nop");
 
 		mbar_writeLong(MCFSIM_DACR0, 0x0000322c);
+		mb();
 		__asm__("nop");
 
 		/* Write to this block to initiate precharge */
 		*(u32 *) (CONFIG_SYS_SDRAM_BASE) = 0xa5a5a5a5;
+		mb();
 		__asm__("nop");
 
 		/* Set RE bit in DACR */
@@ -83,6 +86,7 @@ phys_size_t initdram(int board_type)
 		__asm__("nop");
 
 		*(u32 *) (CONFIG_SYS_SDRAM_BASE + 0x800) = 0xa5a5a5a5;
+		mb();
 	}
 
 	return dramsize;
-- 
1.6.4




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