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-rw-r--r--arch/arm/mach-omap2/board-rx51-sdram.c221
1 files changed, 221 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/board-rx51-sdram.c b/arch/arm/mach-omap2/board-rx51-sdram.c
new file mode 100644
index 00000000000..f392844195d
--- /dev/null
+++ b/arch/arm/mach-omap2/board-rx51-sdram.c
@@ -0,0 +1,221 @@
+/*
+ * SDRC register values for RX51
+ *
+ * Copyright (C) 2008 Nokia Corporation
+ *
+ * Lauri Leukkunen <lauri.leukkunen@nokia.com>
+ *
+ * Original code by Juha Yrjola <juha.yrjola@solidboot.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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+
+#include <plat/io.h>
+#include <plat/common.h>
+#include <plat/clock.h>
+#include <plat/sdrc.h>
+
+
+/* In picoseconds, except for tREF (ns), tXP, tCKE, tWTR (clks) */
+struct sdram_timings {
+ u32 casl;
+ u32 tDAL;
+ u32 tDPL;
+ u32 tRRD;
+ u32 tRCD;
+ u32 tRP;
+ u32 tRAS;
+ u32 tRC;
+ u32 tRFC;
+ u32 tXSR;
+
+ u32 tREF; /* in ns */
+
+ u32 tXP;
+ u32 tCKE;
+ u32 tWTR;
+};
+
+struct omap_sdrc_params rx51_sdrc_params[4];
+
+static const struct sdram_timings rx51_timings[] = {
+ {
+ .casl = 3,
+ .tDAL = 33000,
+ .tDPL = 15000,
+ .tRRD = 12000,
+ .tRCD = 22500,
+ .tRP = 18000,
+ .tRAS = 42000,
+ .tRC = 66000,
+ .tRFC = 138000,
+ .tXSR = 200000,
+
+ .tREF = 7800,
+
+ .tXP = 2,
+ .tCKE = 2,
+ .tWTR = 2
+ },
+};
+
+static unsigned long sdrc_get_fclk_period(long rate)
+{
+ /* In picoseconds */
+ return 1000000000 / rate;
+}
+
+static unsigned int sdrc_ps_to_ticks(unsigned int time_ps, long rate)
+{
+ unsigned long tick_ps;
+
+ /* Calculate in picosecs to yield more exact results */
+ tick_ps = sdrc_get_fclk_period(rate);
+
+ return (time_ps + tick_ps - 1) / tick_ps;
+}
+#undef DEBUG
+#ifdef DEBUG
+static int set_sdrc_timing_regval(u32 *regval, int st_bit, int end_bit,
+ int ticks, long rate, const char *name)
+#else
+static int set_sdrc_timing_regval(u32 *regval, int st_bit, int end_bit,
+ int ticks)
+#endif
+{
+ int mask, nr_bits;
+
+ nr_bits = end_bit - st_bit + 1;
+ if (ticks >= 1 << nr_bits)
+ return -1;
+ mask = (1 << nr_bits) - 1;
+ *regval &= ~(mask << st_bit);
+ *regval |= ticks << st_bit;
+#ifdef DEBUG
+ printk(KERN_INFO "SDRC %s: %i ticks %i ns\n", name, ticks,
+ (unsigned int)sdrc_get_fclk_period(rate) * ticks /
+ 1000);
+#endif
+
+ return 0;
+}
+
+#ifdef DEBUG
+#define SDRC_SET_ONE(reg, st, end, field, rate) \
+ if (set_sdrc_timing_regval((reg), (st), (end), \
+ rx51_timings->field, (rate), #field) < 0) \
+ err = -1;
+#else
+#define SDRC_SET_ONE(reg, st, end, field, rate) \
+ if (set_sdrc_timing_regval((reg), (st), (end), \
+ rx51_timings->field) < 0) \
+ err = -1;
+#endif
+
+#ifdef DEBUG
+static int set_sdrc_timing_regval_ps(u32 *regval, int st_bit, int end_bit,
+ int time, long rate, const char *name)
+#else
+static int set_sdrc_timing_regval_ps(u32 *regval, int st_bit, int end_bit,
+ int time, long rate)
+#endif
+{
+ int ticks, ret;
+ ret = 0;
+
+ if (time == 0)
+ ticks = 0;
+ else
+ ticks = sdrc_ps_to_ticks(time, rate);
+
+#ifdef DEBUG
+ ret = set_sdrc_timing_regval(regval, st_bit, end_bit, ticks,
+ rate, name);
+#else
+ ret = set_sdrc_timing_regval(regval, st_bit, end_bit, ticks);
+#endif
+
+ return ret;
+}
+
+#ifdef DEBUG
+#define SDRC_SET_ONE_PS(reg, st, end, field, rate) \
+ if (set_sdrc_timing_regval_ps((reg), (st), (end), \
+ rx51_timings->field, \
+ (rate), #field) < 0) \
+ err = -1;
+
+#else
+#define SDRC_SET_ONE_PS(reg, st, end, field, rate) \
+ if (set_sdrc_timing_regval_ps((reg), (st), (end), \
+ rx51_timings->field, (rate)) < 0) \
+ err = -1;
+#endif
+
+static int sdrc_timings(int id, long rate)
+{
+ u32 ticks_per_ms;
+ u32 rfr, l;
+ u32 actim_ctrla = 0, actim_ctrlb = 0;
+ u32 rfr_ctrl;
+ int err = 0;
+ long l3_rate = rate / 1000;
+
+ SDRC_SET_ONE_PS(&actim_ctrla, 0, 4, tDAL, l3_rate);
+ SDRC_SET_ONE_PS(&actim_ctrla, 6, 8, tDPL, l3_rate);
+ SDRC_SET_ONE_PS(&actim_ctrla, 9, 11, tRRD, l3_rate);
+ SDRC_SET_ONE_PS(&actim_ctrla, 12, 14, tRCD, l3_rate);
+ SDRC_SET_ONE_PS(&actim_ctrla, 15, 17, tRP, l3_rate);
+ SDRC_SET_ONE_PS(&actim_ctrla, 18, 21, tRAS, l3_rate);
+ SDRC_SET_ONE_PS(&actim_ctrla, 22, 26, tRC, l3_rate);
+ SDRC_SET_ONE_PS(&actim_ctrla, 27, 31, tRFC, l3_rate);
+
+ SDRC_SET_ONE_PS(&actim_ctrlb, 0, 7, tXSR, l3_rate);
+
+ SDRC_SET_ONE(&actim_ctrlb, 8, 10, tXP, l3_rate);
+ SDRC_SET_ONE(&actim_ctrlb, 12, 14, tCKE, l3_rate);
+ SDRC_SET_ONE(&actim_ctrlb, 16, 17, tWTR, l3_rate);
+
+ ticks_per_ms = l3_rate;
+ rfr = rx51_timings[0].tREF * ticks_per_ms / 1000000;
+ if (rfr > 65535 + 50)
+ rfr = 65535;
+ else
+ rfr -= 50;
+
+#ifdef DEBUG
+ printk(KERN_INFO "SDRC tREF: %i ticks\n", rfr);
+#endif
+
+ l = rfr << 8;
+ rfr_ctrl = l | 0x1; /* autorefresh, reload counter with 1xARCV */
+
+ rx51_sdrc_params[id].rate = rate;
+ rx51_sdrc_params[id].actim_ctrla = actim_ctrla;
+ rx51_sdrc_params[id].actim_ctrlb = actim_ctrlb;
+ rx51_sdrc_params[id].rfr_ctrl = rfr_ctrl;
+ rx51_sdrc_params[id].mr = 0x32;
+
+ rx51_sdrc_params[id + 1].rate = 0;
+
+ return err;
+}
+
+struct omap_sdrc_params *rx51_get_sdram_timings(void)
+{
+ int err;
+
+ err = sdrc_timings(0, 41500000);
+ err |= sdrc_timings(1, 83000000);
+ err |= sdrc_timings(2, 166000000);
+
+ return &rx51_sdrc_params[0];
+}
+