driver/ddr/fsl: Add DDR4 support to Freescale DDR driver

Mostly reusing DDR3 driver, this patch adds DDR4 SPD handling, register
calculation and programming.

Signed-off-by: York Sun <yorksun@freescale.com>
diff --git a/include/common_timing_params.h b/include/common_timing_params.h
index 76338d4..821de21 100644
--- a/include/common_timing_params.h
+++ b/include/common_timing_params.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2008 Freescale Semiconductor, Inc.
+ * Copyright 2008-2014 Freescale Semiconductor, Inc.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -14,32 +14,45 @@
 
 	unsigned int tckmin_x_ps;
 	unsigned int tckmax_ps;
-	unsigned int tckmax_max_ps;
 	unsigned int trcd_ps;
 	unsigned int trp_ps;
 	unsigned int tras_ps;
+#if defined(CONFIG_SYS_FSL_DDR3) || defined(CONFIG_SYS_FSL_DDR4)
+	unsigned int taamin_ps;
+#endif
 
-	unsigned int twr_ps;	/* maximum = 63750 ps */
+#ifdef CONFIG_SYS_FSL_DDR4
+	unsigned int trfc1_ps;
+	unsigned int trfc2_ps;
+	unsigned int trfc4_ps;
+	unsigned int trrds_ps;
+	unsigned int trrdl_ps;
+	unsigned int tccdl_ps;
+#else
 	unsigned int twtr_ps;	/* maximum = 63750 ps */
 	unsigned int trfc_ps;	/* maximum = 255 ns + 256 ns + .75 ns
 					   = 511750 ps */
 
 	unsigned int trrd_ps;	/* maximum = 63750 ps */
+	unsigned int trtp_ps;	/* byte 38, spd->trtp */
+#endif
+	unsigned int twr_ps;	/* maximum = 63750 ps */
 	unsigned int trc_ps;	/* maximum = 254 ns + .75 ns = 254750 ps */
 
 	unsigned int refresh_rate_ps;
 	unsigned int extended_op_srt;
 
+#if defined(CONFIG_SYS_FSL_DDR1) || defined(CONFIG_SYS_FSL_DDR2)
 	unsigned int tis_ps;	/* byte 32, spd->ca_setup */
 	unsigned int tih_ps;	/* byte 33, spd->ca_hold */
 	unsigned int tds_ps;	/* byte 34, spd->data_setup */
 	unsigned int tdh_ps;	/* byte 35, spd->data_hold */
-	unsigned int trtp_ps;	/* byte 38, spd->trtp */
 	unsigned int tdqsq_max_ps;	/* byte 44, spd->tdqsq */
 	unsigned int tqhs_ps;	/* byte 45, spd->tqhs */
+#endif
 
 	unsigned int ndimms_present;
-	unsigned int lowest_common_SPD_caslat;
+	unsigned int lowest_common_spd_caslat;
 	unsigned int highest_common_derated_caslat;
 	unsigned int additive_latency;
 	unsigned int all_dimms_burst_lengths_bitmask;