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Diffstat (limited to 'arch/arm/mach-omap2/sdrc.c')
-rw-r--r--arch/arm/mach-omap2/sdrc.c38
1 files changed, 37 insertions, 1 deletions
diff --git a/arch/arm/mach-omap2/sdrc.c b/arch/arm/mach-omap2/sdrc.c
index 24b54d50b893..2a30060cb4b7 100644
--- a/arch/arm/mach-omap2/sdrc.c
+++ b/arch/arm/mach-omap2/sdrc.c
@@ -12,6 +12,7 @@
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
+#undef DEBUG
#include <linux/module.h>
#include <linux/kernel.h>
@@ -31,9 +32,42 @@
#include <mach/sdrc.h>
#include "sdrc.h"
+static struct omap_sdrc_params *sdrc_init_params;
+
void __iomem *omap2_sdrc_base;
void __iomem *omap2_sms_base;
+
+/**
+ * omap2_sdrc_get_params - return SDRC register values for a given clock rate
+ * @r: SDRC clock rate (in Hz)
+ *
+ * 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.
+ */
+struct omap_sdrc_params *omap2_sdrc_get_params(unsigned long r)
+{
+ struct omap_sdrc_params *sp;
+
+ sp = sdrc_init_params;
+
+ while (sp->rate != r)
+ sp++;
+
+ if (!sp->rate)
+ return NULL;
+
+ return sp;
+}
+
+
void __init omap2_set_globals_sdrc(struct omap_globals *omap2_globals)
{
omap2_sdrc_base = omap2_globals->sdrc;
@@ -41,7 +75,7 @@ void __init omap2_set_globals_sdrc(struct omap_globals *omap2_globals)
}
/* turn on smart idle modes for SDRAM scheduler and controller */
-void __init omap2_sdrc_init(void)
+void __init omap2_sdrc_init(struct omap_sdrc_params *sp)
{
u32 l;
@@ -54,4 +88,6 @@ void __init omap2_sdrc_init(void)
l &= ~(0x3 << 3);
l |= (0x2 << 3);
sdrc_write_reg(l, SDRC_SYSCONFIG);
+
+ sdrc_init_params = sp;
}