fsl-ddr: add override for the Rtt_Wr
Different boards may require different settings of Dynamic ODT (Rtt_Wr).
We provide a means to allow the board specific code to provide its own
value of Rtt_Wr.
Signed-off-by: Dave Liu <daveliu@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/cpu/mpc8xxx/ddr/ctrl_regs.c b/cpu/mpc8xxx/ddr/ctrl_regs.c
index 5e37ca6..3be7e22 100644
--- a/cpu/mpc8xxx/ddr/ctrl_regs.c
+++ b/cpu/mpc8xxx/ddr/ctrl_regs.c
@@ -576,18 +576,22 @@
}
/* DDR SDRAM Mode configuration 2 (DDR_SDRAM_MODE_2) */
-static void set_ddr_sdram_mode_2(fsl_ddr_cfg_regs_t *ddr)
+static void set_ddr_sdram_mode_2(fsl_ddr_cfg_regs_t *ddr,
+ const memctl_options_t *popts)
{
unsigned short esdmode2 = 0; /* Extended SDRAM mode 2 */
unsigned short esdmode3 = 0; /* Extended SDRAM mode 3 */
#if defined(CONFIG_FSL_DDR3)
- unsigned int rtt_wr = 2; /* 120 ohm Rtt_WR */
+ unsigned int rtt_wr = 0; /* Rtt_WR - dynamic ODT off */
unsigned int srt = 0; /* self-refresh temerature, normal range */
unsigned int asr = 0; /* auto self-refresh disable */
unsigned int cwl = compute_cas_write_latency() - 5;
unsigned int pasr = 0; /* partial array self refresh disable */
+ if (popts->rtt_override)
+ rtt_wr = popts->rtt_wr_override_value;
+
esdmode2 = (0
| ((rtt_wr & 0x3) << 9)
| ((srt & 0x1) << 7)
@@ -1330,7 +1334,7 @@
set_ddr_sdram_cfg_2(ddr, popts);
set_ddr_sdram_mode(ddr, popts, common_dimm,
cas_latency, additive_latency);
- set_ddr_sdram_mode_2(ddr);
+ set_ddr_sdram_mode_2(ddr, popts);
set_ddr_sdram_interval(ddr, popts, common_dimm);
set_ddr_data_init(ddr);
set_ddr_sdram_clk_cntl(ddr, popts);