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-rw-r--r--arch/arm/mach-omap2/sdrc.c93
1 files changed, 93 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/sdrc.c b/arch/arm/mach-omap2/sdrc.c
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+++ b/arch/arm/mach-omap2/sdrc.c
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+/*
+ * SMS/SDRC (SDRAM controller) common code for OMAP2/3
+ *
+ * Copyright (C) 2005, 2008 Texas Instruments Inc.
+ * Copyright (C) 2005, 2008 Nokia Corporation
+ *
+ * Tony Lindgren <tony@atomide.com>
+ * Paul Walmsley
+ * Richard Woodruff <r-woodruff2@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * 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>
+#include <linux/device.h>
+#include <linux/list.h>
+#include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+
+#include <mach/common.h>
+#include <mach/clock.h>
+#include <mach/sram.h>
+
+#include "prm.h"
+
+#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;
+ omap2_sms_base = omap2_globals->sms;
+}
+
+/* turn on smart idle modes for SDRAM scheduler and controller */
+void __init omap2_sdrc_init(struct omap_sdrc_params *sp)
+{
+ u32 l;
+
+ l = sms_read_reg(SMS_SYSCONFIG);
+ l &= ~(0x3 << 3);
+ l |= (0x2 << 3);
+ sms_write_reg(l, SMS_SYSCONFIG);
+
+ l = sdrc_read_reg(SDRC_SYSCONFIG);
+ l &= ~(0x3 << 3);
+ l |= (0x2 << 3);
+ sdrc_write_reg(l, SDRC_SYSCONFIG);
+
+ sdrc_init_params = sp;
+}