ppc4xx: Update Katmai/44x_spd_ddr2.c code for optimal DDR2 setup
On Katmai the complete auto-calibration somehow doesn't seem to
produce the best results, meaning optimal values for RQFD/RFFD.
This was discovered by GDA using a high bandwidth scope,
analyzing the DDR2 signals. GDA provided a fixed value for RQFD,
so now on Katmai "only" RFFD is auto-calibrated.
This patch also adds RDCC calibration as mentioned on page 7 of
the AMCC PowerPC440SP/SPe DDR2 application note:
"DDR1/DDR2 Initialization Sequence and Dynamic Tuning"
Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/board/amcc/katmai/katmai.c b/board/amcc/katmai/katmai.c
index 25c9a22..e41caaf 100644
--- a/board/amcc/katmai/katmai.c
+++ b/board/amcc/katmai/katmai.c
@@ -1,5 +1,5 @@
/*
- * (C) Copyright 2007
+ * (C) Copyright 2007-2008
* Stefan Roese, DENX Software Engineering, sr@denx.de.
*
* See file CREDITS for list of people who contributed to this
@@ -246,6 +246,18 @@
return 0;
}
+/*
+ * Override the default functions in cpu/ppc4xx/44x_spd_ddr2.c with
+ * board specific values.
+ */
+u32 ddr_wrdtr(u32 default_val) {
+ return (SDRAM_WRDTR_LLWP_1_CYC | SDRAM_WRDTR_WTR_180_DEG_ADV | 0x823);
+}
+
+u32 ddr_clktr(u32 default_val) {
+ return (SDRAM_CLKTR_CLKP_90_DEG_ADV);
+}
+
#if defined(CFG_DRAM_TEST)
int testdram (void)
{