OMAP3 SDRC: add support for 2 SDRAM chip selects

Some OMAP3 boards (Beagle Cx, Overo, RX51, Pandora) have 2
SDRAM parts connected to the SDRC.

This patch adds the following:
- add a new argument of type omap_sdrc_params struct*
to omap2_init_common_hw and omap2_sdrc_init for the 2nd CS params
- adapted the OMAP boards files to the new prototype of
omap2_init_common_hw
- add the SDRC 2nd CS registers offsets defines
- adapt the sram sleep code to configure the SDRC for the 2nd CS

Note: If the 2nd param to omap2_init_common_hw is NULL, then the
parameters are not programmed into the SDRC CS1 registers

Tested on 3430 SDP and Beagleboard rev C2 and B5, with
suspend/resume and frequency changes (cpufreq).

Signed-off-by: Jean Pihet <jpihet@mvista.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
diff --git a/arch/arm/mach-omap2/sdrc.c b/arch/arm/mach-omap2/sdrc.c
index 2045441..2e9e38d 100644
--- a/arch/arm/mach-omap2/sdrc.c
+++ b/arch/arm/mach-omap2/sdrc.c
@@ -32,7 +32,7 @@
 #include <mach/sdrc.h>
 #include "sdrc.h"
 
-static struct omap_sdrc_params *sdrc_init_params;
+static struct omap_sdrc_params *sdrc_init_params_cs0, *sdrc_init_params_cs1;
 
 void __iomem *omap2_sdrc_base;
 void __iomem *omap2_sms_base;
@@ -45,33 +45,49 @@
 /**
  * omap2_sdrc_get_params - return SDRC register values for a given clock rate
  * @r: SDRC clock rate (in Hz)
+ * @sdrc_cs0: chip select 0 ram timings **
+ * @sdrc_cs1: chip select 1 ram timings **
  *
  * Return pre-calculated values for the SDRC_ACTIM_CTRLA,
- * SDRC_ACTIM_CTRLB, SDRC_RFR_CTRL, and SDRC_MR registers, for a given
- * SDRC clock rate 'r'.  These parameters control various timing
- * delays in the SDRAM controller that are expressed in terms of the
- * number of SDRC clock cycles to wait; hence the clock rate
- * dependency. Note that sdrc_init_params must be sorted rate
- * descending.  Also assumes that both chip-selects use the same
- * timing parameters.  Returns a struct omap_sdrc_params * upon
- * success, or NULL upon failure.
+ *  SDRC_ACTIM_CTRLB, SDRC_RFR_CTRL and SDRC_MR registers in sdrc_cs[01]
+ *  structs,for a given SDRC clock rate 'r'.
+ * These parameters control various timing delays in the SDRAM controller
+ *  that are expressed in terms of the number of SDRC clock cycles to
+ *  wait; hence the clock rate dependency.
+ *
+ * Supports 2 different timing parameters for both chip selects.
+ *
+ * Note 1: the sdrc_init_params_cs[01] must be sorted rate descending.
+ * Note 2: If sdrc_init_params_cs_1 is not NULL it must be of same size
+ *  as sdrc_init_params_cs_0.
+ *
+ * Fills in the struct omap_sdrc_params * for each chip select.
+ * Returns 0 upon success or -1 upon failure.
  */
-struct omap_sdrc_params *omap2_sdrc_get_params(unsigned long r)
+int omap2_sdrc_get_params(unsigned long r,
+			  struct omap_sdrc_params **sdrc_cs0,
+			  struct omap_sdrc_params **sdrc_cs1)
 {
-	struct omap_sdrc_params *sp;
+	struct omap_sdrc_params *sp0, *sp1;
 
-	if (!sdrc_init_params)
-		return NULL;
+	if (!sdrc_init_params_cs0)
+		return -1;
 
-	sp = sdrc_init_params;
+	sp0 = sdrc_init_params_cs0;
+	sp1 = sdrc_init_params_cs1;
 
-	while (sp->rate && sp->rate != r)
-		sp++;
+	while (sp0->rate && sp0->rate != r) {
+		sp0++;
+		if (sdrc_init_params_cs1)
+			sp1++;
+	}
 
-	if (!sp->rate)
-		return NULL;
+	if (!sp0->rate)
+		return -1;
 
-	return sp;
+	*sdrc_cs0 = sp0;
+	*sdrc_cs1 = sp1;
+	return 0;
 }
 
 
@@ -83,13 +99,15 @@
 
 /**
  * omap2_sdrc_init - initialize SMS, SDRC devices on boot
- * @sp: pointer to a null-terminated list of struct omap_sdrc_params
+ * @sdrc_cs[01]: pointers to a null-terminated list of struct omap_sdrc_params
+ *  Support for 2 chip selects timings
  *
  * Turn on smart idle modes for SDRAM scheduler and controller.
  * Program a known-good configuration for the SDRC to deal with buggy
  * bootloaders.
  */
-void __init omap2_sdrc_init(struct omap_sdrc_params *sp)
+void __init omap2_sdrc_init(struct omap_sdrc_params *sdrc_cs0,
+			    struct omap_sdrc_params *sdrc_cs1)
 {
 	u32 l;
 
@@ -103,7 +121,8 @@
 	l |= (0x2 << 3);
 	sdrc_write_reg(l, SDRC_SYSCONFIG);
 
-	sdrc_init_params = sp;
+	sdrc_init_params_cs0 = sdrc_cs0;
+	sdrc_init_params_cs1 = sdrc_cs1;
 
 	/* XXX Enable SRFRONIDLEREQ here also? */
 	l = (1 << SDRC_POWER_EXTCLKDIS_SHIFT) |