[U-Boot] [PATCH 6/8] powerpc/8xxx: Improvement to DDR parameters
Kumar Gala
galak at kernel.crashing.org
Wed Jul 14 17:15:00 CEST 2010
From: york <yorksun at freescale.com>
Changes for P2020DS DDR applies to other 8xxx platform
Signed-off-by: York Sun <yorksun at freescale.com>
---
arch/powerpc/cpu/mpc8xxx/ddr/ctrl_regs.c | 14 +++++++-------
arch/powerpc/cpu/mpc8xxx/ddr/options.c | 1 +
2 files changed, 8 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/cpu/mpc8xxx/ddr/ctrl_regs.c b/arch/powerpc/cpu/mpc8xxx/ddr/ctrl_regs.c
index b2962d2..dccb7aa 100644
--- a/arch/powerpc/cpu/mpc8xxx/ddr/ctrl_regs.c
+++ b/arch/powerpc/cpu/mpc8xxx/ddr/ctrl_regs.c
@@ -199,7 +199,7 @@ static void set_timing_cfg_0(fsl_ddr_cfg_regs_t *ddr)
unsigned char act_pd_exit_mclk;
/* Precharge powerdown exit timing (tXP). */
unsigned char pre_pd_exit_mclk;
- /* Precharge powerdown exit timing (tAXPD). */
+ /* ODT powerdown exit timing (tAXPD). */
unsigned char taxpd_mclk;
/* Mode register set cycle time (tMRD). */
unsigned char tmrd_mclk;
@@ -211,13 +211,13 @@ static void set_timing_cfg_0(fsl_ddr_cfg_regs_t *ddr)
* we use the tXP instead of it.
* tXP=max(3nCK, 7.5ns) for DDR3.
* spec has not the tAXPD, we use
- * tAXPD=8, need design to confirm.
+ * tAXPD=1, need design to confirm.
*/
int tXP = max((get_memory_clk_period_ps() * 3), 7500); /* unit=ps */
act_pd_exit_mclk = picos_to_mclk(tXP);
/* Mode register MR0[A12] is '1' - fast exit */
pre_pd_exit_mclk = act_pd_exit_mclk;
- taxpd_mclk = 8;
+ taxpd_mclk = 1;
tmrd_mclk = 4;
/* set the turnaround time */
trwt_mclk = 1;
@@ -1031,9 +1031,9 @@ static void set_timing_cfg_5(fsl_ddr_cfg_regs_t *ddr)
unsigned int wodt_off = 0; /* Write to ODT off */
#if defined(CONFIG_FSL_DDR3)
- rodt_on = 3; /* 2 clocks */
+ rodt_on = 2; /* 2 clocks */
rodt_off = 4; /* 4 clocks */
- wodt_on = 2; /* 1 clocks */
+ wodt_on = 1; /* 1 clocks */
wodt_off = 4; /* 4 clocks */
#endif
@@ -1106,9 +1106,9 @@ static void set_ddr_wrlvl_cntl(fsl_ddr_cfg_regs_t *ddr, unsigned int wrlvl_en,
/*
* Write leveling repetition time
* at least tWLO + 6 clocks clocks
- * we set it 32
+ * we set it 64
*/
- wrlvl_wlr = 0x5;
+ wrlvl_wlr = 0x6;
/*
* Write leveling start time
* The value use for the DQS_ADJUST for the first sample
diff --git a/arch/powerpc/cpu/mpc8xxx/ddr/options.c b/arch/powerpc/cpu/mpc8xxx/ddr/options.c
index e4805d3..774c0e4 100644
--- a/arch/powerpc/cpu/mpc8xxx/ddr/options.c
+++ b/arch/powerpc/cpu/mpc8xxx/ddr/options.c
@@ -204,6 +204,7 @@ unsigned int populate_memctl_options(int all_DIMMs_registered,
* meet the tQDSS under different loading.
*/
popts->wrlvl_en = 1;
+ popts->zq_en = 1;
popts->wrlvl_override = 0;
#endif
--
1.6.0.6
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