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authorDave Liu <daveliu@freescale.com>2009-12-16 10:24:37 -0600
committerKumar Gala <galak@kernel.crashing.org>2010-01-05 13:49:10 -0600
commitbdc9f7b5eab8d5edd8a8cc5d80ef080836b00e85 (patch)
tree57b6745a30901b1f9ea7b33e52dae00cbd951136 /cpu/mpc8xxx/ddr
parent0a71c92c7e1e565111cb34cd389a21ec500ca5c1 (diff)
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fsl-ddr: add the override for write leveling
add the override for write leveling sampling and start time according to specific board. Signed-off-by: Dave Liu <daveliu@freescale.com> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Diffstat (limited to 'cpu/mpc8xxx/ddr')
-rw-r--r--cpu/mpc8xxx/ddr/ctrl_regs.c20
-rw-r--r--cpu/mpc8xxx/ddr/options.c1
2 files changed, 15 insertions, 6 deletions
diff --git a/cpu/mpc8xxx/ddr/ctrl_regs.c b/cpu/mpc8xxx/ddr/ctrl_regs.c
index a92f1a3..5e37ca6 100644
--- a/cpu/mpc8xxx/ddr/ctrl_regs.c
+++ b/cpu/mpc8xxx/ddr/ctrl_regs.c
@@ -1002,8 +1002,8 @@ static void set_ddr_zq_cntl(fsl_ddr_cfg_regs_t *ddr, unsigned int zq_en)
}
/* DDR Write Leveling Control (DDR_WRLVL_CNTL) */
-static void set_ddr_wrlvl_cntl(fsl_ddr_cfg_regs_t *ddr,
- unsigned int wrlvl_en)
+static void set_ddr_wrlvl_cntl(fsl_ddr_cfg_regs_t *ddr, unsigned int wrlvl_en,
+ const memctl_options_t *popts)
{
/*
* First DQS pulse rising edge after margining mode
@@ -1030,8 +1030,9 @@ static void set_ddr_wrlvl_cntl(fsl_ddr_cfg_regs_t *ddr,
/* tWL_DQSEN min = 25 nCK, we set it 32 */
wrlvl_dqsen = 0x5;
/*
- * Write leveling sample time at least need 14 clocks
- * due to tWLO = 9, we set it 15 clocks
+ * Write leveling sample time at least need 6 clocks
+ * higher than tWLO to allow enough time for progagation
+ * delay and sampling the prime data bits.
*/
wrlvl_smpl = 0xf;
/*
@@ -1044,9 +1045,16 @@ static void set_ddr_wrlvl_cntl(fsl_ddr_cfg_regs_t *ddr,
* Write leveling start time
* The value use for the DQS_ADJUST for the first sample
* when write leveling is enabled.
- * we set it 1 clock delay
*/
wrlvl_start = 0x8;
+ /*
+ * Override the write leveling sample and start time
+ * according to specific board
+ */
+ if (popts->wrlvl_override) {
+ wrlvl_smpl = popts->wrlvl_sample;
+ wrlvl_start = popts->wrlvl_start;
+ }
}
ddr->ddr_wrlvl_cntl = (0
@@ -1332,7 +1340,7 @@ compute_fsl_memctl_config_regs(const memctl_options_t *popts,
set_timing_cfg_5(ddr);
set_ddr_zq_cntl(ddr, zq_en);
- set_ddr_wrlvl_cntl(ddr, wrlvl_en);
+ set_ddr_wrlvl_cntl(ddr, wrlvl_en, popts);
set_ddr_sr_cntr(ddr, sr_it);
diff --git a/cpu/mpc8xxx/ddr/options.c b/cpu/mpc8xxx/ddr/options.c
index 2e030c1..3dcd33d 100644
--- a/cpu/mpc8xxx/ddr/options.c
+++ b/cpu/mpc8xxx/ddr/options.c
@@ -198,6 +198,7 @@ unsigned int populate_memctl_options(int all_DIMMs_registered,
* meet the tQDSS under different loading.
*/
popts->wrlvl_en = 1;
+ popts->wrlvl_override = 0;
#endif
/*