[U-Boot] [PATCH v2 08/15] powerpc/km8321: define CONFIG_SYS_DDRCDR

Valentin Longchamp valentin.longchamp at keymile.com
Tue Nov 17 10:53:31 CET 2015


On the km8321 boards is CONFIG_SYS_DDRCDR not defined, which leads to
the DDRCDR not being configured at startup and still containing the
reset value.

The required settings for our km8321 hardware designs are different than
the reset value and must be set with CONFIG_SYS_DDRCDR, that is used
by mpc83xx's cpu_init_f function at early CPU initialization.

The important settings are the DDR2 internal voltage level and the
half-strength "drivers".

In our case where the DRAM chips are soldered on board and the routing
for these signals under control, half-strength is sufficient as a few
measurements done in the lasts have shown. Since all the hardware
qualification tests have been performed with half strength, the nominal
strength settings are removed in favor of the default reset half
strength settings.

Signed-off-by: Valentin Longchamp <valentin.longchamp at keymile.com>

---

Changes in v2:
- Squashed commit 9/17 and 10/17 together into a single commit

 include/configs/km/km8321-common.h | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/include/configs/km/km8321-common.h b/include/configs/km/km8321-common.h
index 058b0ab..b2e68e3 100644
--- a/include/configs/km/km8321-common.h
+++ b/include/configs/km/km8321-common.h
@@ -65,6 +65,12 @@
 	HRCWH_BIG_ENDIAN | \
 	HRCWH_LALE_NORMAL)
 
+#define CONFIG_SYS_DDRCDR (\
+	DDRCDR_EN | \
+	DDRCDR_PZ_MAXZ | \
+	DDRCDR_NZ_MAXZ | \
+	DDRCDR_M_ODR)
+
 #define CONFIG_SYS_DDR_CS0_BNDS		0x0000007f
 #define CONFIG_SYS_DDR_SDRAM_CFG	(SDRAM_CFG_SDRAM_TYPE_DDR2 | \
 					 SDRAM_CFG_32_BE | \
-- 
1.8.3.1



More information about the U-Boot mailing list