ppc4xx: Reset and relock memory DLL after SDRAM_CLKTR change

After changing SDRAM_CLKTR phase value rerun the memory preload
initialization sequence (INITPLR) to reset and relock the memory
DLL. Changing the SDRAM_CLKTR memory clock phase coarse timing
adjustment effects the phase relationship of the internal, to the
PPC chip, and external, to the PPC chip, versions of MEMCLK_OUT.

Signed-off-by: Adam Graham <agraham@amcc.com>
Signed-off-by: Victor Gallardo <vgallardo@amcc.com>
Signed-off-by: Stefan Roese <sr@denx.de>

diff --git a/cpu/ppc4xx/4xx_ibm_ddr2_autocalib.c b/cpu/ppc4xx/4xx_ibm_ddr2_autocalib.c
index 83b9883a7726efa896300848fb4db4699f51b2dd..47ab39bdb6a871426ab57edea01b5322e9f17c7a 100644 (file)
--- a/cpu/ppc4xx/4xx_ibm_ddr2_autocalib.c
+++ b/cpu/ppc4xx/4xx_ibm_ddr2_autocalib.c
@@ -174,6 +174,23 @@ static inline void ecc_clear_status_reg(void)
 #endif
 }
 
+/*
+ * Reset and relock memory DLL after SDRAM_CLKTR change
+ */
+static inline void relock_memory_DLL(void)
+{
+       u32 reg;
+
+       mtsdram(SDRAM_MCOPT2, SDRAM_MCOPT2_IPTR_EXECUTE);
+
+       do {
+               mfsdram(SDRAM_MCSTAT, reg);
+       } while (!(reg & SDRAM_MCSTAT_MIC_COMP));
+
+       mfsdram(SDRAM_MCOPT2, reg);
+       mtsdram(SDRAM_MCOPT2, reg | SDRAM_MCOPT2_DCEN_ENABLE);
+}
+
 static int ecc_check_status_reg(void)
 {
        u32 ecc_status;
@@ -981,6 +998,8 @@ u32 DQS_autocalibration(void)
 
                mtsdram(SDRAM_CLKTR, clkp << 30);
 
+               relock_memory_DLL();
+
                putc('\b');
                putc(slash[loopi++ % 8]);
 
@@ -1170,6 +1189,8 @@ u32 DQS_autocalibration(void)
 
                mtsdram(SDRAM_CLKTR, tcal.clocks.clktr << 30);
 
+               relock_memory_DLL();
+
                mfsdram(SDRAM_RQDC, rqdc_reg);
                rqdc_reg &= ~(SDRAM_RQDC_RQFD_MASK);
                mtsdram(SDRAM_RQDC, rqdc_reg |