ppc4xx: Add CONFIG_DDR_RFDC_FIXED to allow board specific RFDC values
Using this define, a board can define an opimized RFDC value and use
the auto calibration code to "tune" the remaining DDR2 controller
calibration register.
Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/arch/powerpc/cpu/ppc4xx/4xx_ibm_ddr2_autocalib.c b/arch/powerpc/cpu/ppc4xx/4xx_ibm_ddr2_autocalib.c
index 0f69ef9..2fee995 100644
--- a/arch/powerpc/cpu/ppc4xx/4xx_ibm_ddr2_autocalib.c
+++ b/arch/powerpc/cpu/ppc4xx/4xx_ibm_ddr2_autocalib.c
@@ -767,6 +767,13 @@
debug("\n\n");
+#if defined(CONFIG_DDR_RFDC_FIXED)
+ mtsdram(SDRAM_RFDC, CONFIG_DDR_RFDC_FIXED);
+ size = 512;
+ rffd_average = CONFIG_DDR_RFDC_FIXED & SDRAM_RFDC_RFFD_MASK;
+ mfsdram(SDRAM_RDCC, rdcc); /* record this value */
+ cal->rdcc = rdcc;
+#else /* CONFIG_DDR_RFDC_FIXED */
in_window = 0;
rdcc = 0;
@@ -830,6 +837,7 @@
rffd_average = SDRAM_RFDC_RFFD_MAX;
mtsdram(SDRAM_RFDC, rfdc_reg | SDRAM_RFDC_RFFD_ENCODE(rffd_average));
+#endif /* CONFIG_DDR_RFDC_FIXED */
rffd = rffd_average;
in_window = 0;
@@ -1211,10 +1219,14 @@
debug("*** best_result: read value SDRAM_RQDC 0x%08x\n",
rqdc_reg);
+#if defined(CONFIG_DDR_RFDC_FIXED)
+ mtsdram(SDRAM_RFDC, CONFIG_DDR_RFDC_FIXED);
+#else /* CONFIG_DDR_RFDC_FIXED */
mfsdram(SDRAM_RFDC, rfdc_reg);
rfdc_reg &= ~(SDRAM_RFDC_RFFD_MASK);
mtsdram(SDRAM_RFDC, rfdc_reg |
SDRAM_RFDC_RFFD_ENCODE(tcal.autocal.rffd));
+#endif /* CONFIG_DDR_RFDC_FIXED */
mfsdram(SDRAM_RFDC, rfdc_reg);
debug("*** best_result: read value SDRAM_RFDC 0x%08x\n",