[U-Boot-Users] [PATCH v2] mpc83xx: Correct the burst length for DDR2 with 32 bits

Dave Liu r63238 at freescale.com
Sat Aug 4 07:37:39 CEST 2007


The burst length should be 4 for DDR2 with 32 bits bus

Signed-off-by: Dave Liu <daveliu at freescale.com>
---
 cpu/mpc83xx/spd_sdram.c |   13 ++++++++++---
 1 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/cpu/mpc83xx/spd_sdram.c b/cpu/mpc83xx/spd_sdram.c
index 647813f..2c17cee 100644
--- a/cpu/mpc83xx/spd_sdram.c
+++ b/cpu/mpc83xx/spd_sdram.c
@@ -574,7 +574,10 @@ long int spd_sdram()
 
 	/* Check DIMM data bus width */
 	if (spd.dataw_lsb == 0x20) {
-		burstlen = 0x03; /* 32 bit data bus, burst len is 8 */
+		if (spd.mem_type == SPD_MEMTYPE_DDR)
+			burstlen = 0x03; /* 32 bit data bus, burst len is 8 */
+		if (spd.mem_type == SPD_MEMTYPE_DDR2)
+			burstlen = 0x02; /* 32 bit data bus, burst len is 4 */
 		printf("\n   DDR DIMM: data bus width is 32 bit");
 	} else {
 		burstlen = 0x02; /* Others act as 64 bit bus, burst len is 4 */
@@ -730,8 +733,12 @@ long int spd_sdram()
 		sdram_cfg |= 0x10000000;
 
 	/* The DIMM is 32bit width */
-	if (spd.dataw_lsb == 0x20)
-		sdram_cfg |= 0x000C0000;
+	if (spd.dataw_lsb == 0x20) {
+		if (spd.mem_type == SPD_MEMTYPE_DDR)
+			sdram_cfg |= 0x000C0000;
+		if (spd.mem_type == SPD_MEMTYPE_DDR2)
+			sdram_cfg |= 0x00080000;
+	}
 
 	ddrc_ecc_enable = 0;
 
-- 
1.5.3.rc2.29.gc4640f







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