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authorDave Liu <daveliu@freescale.com>2009-02-25 12:31:32 +0800
committerKim Phillips <kim.phillips@freescale.com>2009-03-05 18:20:37 -0600
commit5b0055547f0246908b79cc300170d87380b69e18 (patch)
tree6141a20ef84fbfdab53d5747fe482896c31ad694
parentb7be63abec45858c044f0fbd6aeef524c4663f9b (diff)
downloadu-boot-linaro-stable-5b0055547f0246908b79cc300170d87380b69e18.tar.gz
83xx: Fix some bugs in spd sdram code
1. RD_TO_PRE missed to add the AL, and need min 2 clocks for tRTP according to DDR2 JEDEC spec. 2. WRTORD - tWTR need min 2 clocks according to DDR2 JEDEC spec. 3. add the support of DDR2-533,667,800 DIMMs 4. cpo 5. make the AL to min to gain better performance. The Micron MT9HTF6472CHY-667D1 DIMMs test passed on MPC837xEMDS platform at 266MHz/333MHz/400MHz data rate. items 1, 2 and 5: Acked-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se> Reported-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se> Signed-off-by: Dave Liu <daveliu@freescale.com> Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
-rw-r--r--cpu/mpc83xx/spd_sdram.c26
1 files changed, 23 insertions, 3 deletions
diff --git a/cpu/mpc83xx/spd_sdram.c b/cpu/mpc83xx/spd_sdram.c
index 42a4e675d..ff15cda7a 100644
--- a/cpu/mpc83xx/spd_sdram.c
+++ b/cpu/mpc83xx/spd_sdram.c
@@ -319,7 +319,20 @@ long int spd_sdram()
ddrc_clk = gd->mem_clk / 1000000;
effective_data_rate = 0;
- if (max_data_rate >= 390 && max_data_rate < 460) { /* it is DDR 400 */
+ if (max_data_rate >= 460) { /* it is DDR2-800, 667, 533 */
+ if (spd.cas_lat & 0x08)
+ caslat = 3;
+ else
+ caslat = 4;
+ if (ddrc_clk <= 460 && ddrc_clk > 350)
+ effective_data_rate = 400;
+ else if (ddrc_clk <=350 && ddrc_clk > 280)
+ effective_data_rate = 333;
+ else if (ddrc_clk <= 280 && ddrc_clk > 230)
+ effective_data_rate = 266;
+ else
+ effective_data_rate = 200;
+ } else if (max_data_rate >= 390 && max_data_rate < 460) { /* it is DDR 400 */
if (ddrc_clk <= 460 && ddrc_clk > 350) {
/* DDR controller clk at 350~460 */
effective_data_rate = 400; /* 5ns */
@@ -466,6 +479,8 @@ long int spd_sdram()
} else {
twr_clk = picos_to_clk(spd.twr * 250);
twtr_clk = picos_to_clk(spd.twtr * 250);
+ if (twtr_clk < 2)
+ twtr_clk = 2;
}
/*
@@ -529,7 +544,7 @@ long int spd_sdram()
if (spd.mem_type == SPD_MEMTYPE_DDR2
&& (odt_wr_cfg || odt_rd_cfg)
&& (caslat < 4)) {
- add_lat = trcd_clk - 1;
+ add_lat = 4 - caslat;
if ((add_lat + caslat) < 4) {
add_lat = 0;
}
@@ -566,6 +581,9 @@ long int spd_sdram()
/* Convert SPD value from quarter nanos to picos. */
trtp_clk = picos_to_clk(spd.trtp * 250);
+ if (trtp_clk < 2)
+ trtp_clk = 2;
+ trtp_clk += add_lat;
cke_min_clk = 3; /* By the book. */
four_act = picos_to_clk(37500); /* By the book. 1k pages? */
@@ -579,7 +597,9 @@ long int spd_sdram()
if (spd.mem_type == SPD_MEMTYPE_DDR2) {
if (effective_data_rate == 266) {
cpo = 0x4; /* READ_LAT + 1/2 */
- } else if (effective_data_rate == 333 || effective_data_rate == 400) {
+ } else if (effective_data_rate == 333) {
+ cpo = 0x6; /* READ_LAT + 1 */
+ } else if (effective_data_rate == 400) {
cpo = 0x7; /* READ_LAT + 5/4 */
} else {
/* Automatic calibration */