2 * SDRC register values for Nokia boards
4 * Copyright (C) 2008, 2010-2011 Nokia Corporation
6 * Lauri Leukkunen <lauri.leukkunen@nokia.com>
8 * Original code by Juha Yrjola <juha.yrjola@solidboot.com>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
15 #include <linux/kernel.h>
16 #include <linux/clk.h>
17 #include <linux/err.h>
21 #include "sdram-nokia.h"
24 /* In picoseconds, except for tREF (ns), tXP, tCKE, tWTR (clks) */
25 struct sdram_timings {
44 static const struct sdram_timings nokia_97dot6mhz_timings[] = {
65 static const struct sdram_timings nokia_166mhz_timings[] = {
86 static const struct sdram_timings nokia_195dot2mhz_timings[] = {
107 static const struct sdram_timings nokia_200mhz_timings[] = {
128 static const struct {
130 struct sdram_timings const *data;
131 } nokia_timings[] = {
132 { 83000000, nokia_166mhz_timings },
133 { 97600000, nokia_97dot6mhz_timings },
134 { 100000000, nokia_200mhz_timings },
135 { 166000000, nokia_166mhz_timings },
136 { 195200000, nokia_195dot2mhz_timings },
137 { 200000000, nokia_200mhz_timings },
139 static struct omap_sdrc_params nokia_sdrc_params[ARRAY_SIZE(nokia_timings) + 1];
141 static unsigned long sdrc_get_fclk_period(long rate)
144 return 1000000000 / rate;
147 static unsigned int sdrc_ps_to_ticks(unsigned int time_ps, long rate)
149 unsigned long tick_ps;
151 /* Calculate in picosecs to yield more exact results */
152 tick_ps = sdrc_get_fclk_period(rate);
154 return (time_ps + tick_ps - 1) / tick_ps;
158 static int set_sdrc_timing_regval(u32 *regval, int st_bit, int end_bit,
159 int ticks, long rate, const char *name)
161 static int set_sdrc_timing_regval(u32 *regval, int st_bit, int end_bit,
167 nr_bits = end_bit - st_bit + 1;
168 if (ticks >= 1 << nr_bits)
170 mask = (1 << nr_bits) - 1;
171 *regval &= ~(mask << st_bit);
172 *regval |= ticks << st_bit;
174 printk(KERN_INFO "SDRC %s: %i ticks %i ns\n", name, ticks,
175 (unsigned int)sdrc_get_fclk_period(rate) * ticks /
183 #define SDRC_SET_ONE(reg, st, end, field, rate) \
184 if (set_sdrc_timing_regval((reg), (st), (end), \
185 memory_timings->field, (rate), #field) < 0) \
188 #define SDRC_SET_ONE(reg, st, end, field, rate) \
189 if (set_sdrc_timing_regval((reg), (st), (end), \
190 memory_timings->field) < 0) \
195 static int set_sdrc_timing_regval_ps(u32 *regval, int st_bit, int end_bit,
196 int time, long rate, const char *name)
198 static int set_sdrc_timing_regval_ps(u32 *regval, int st_bit, int end_bit,
208 ticks = sdrc_ps_to_ticks(time, rate);
211 ret = set_sdrc_timing_regval(regval, st_bit, end_bit, ticks,
214 ret = set_sdrc_timing_regval(regval, st_bit, end_bit, ticks);
221 #define SDRC_SET_ONE_PS(reg, st, end, field, rate) \
222 if (set_sdrc_timing_regval_ps((reg), (st), (end), \
223 memory_timings->field, \
224 (rate), #field) < 0) \
228 #define SDRC_SET_ONE_PS(reg, st, end, field, rate) \
229 if (set_sdrc_timing_regval_ps((reg), (st), (end), \
230 memory_timings->field, (rate)) < 0) \
234 static int sdrc_timings(int id, long rate,
235 const struct sdram_timings *memory_timings)
239 u32 actim_ctrla = 0, actim_ctrlb = 0;
242 long l3_rate = rate / 1000;
244 SDRC_SET_ONE_PS(&actim_ctrla, 0, 4, tDAL, l3_rate);
245 SDRC_SET_ONE_PS(&actim_ctrla, 6, 8, tDPL, l3_rate);
246 SDRC_SET_ONE_PS(&actim_ctrla, 9, 11, tRRD, l3_rate);
247 SDRC_SET_ONE_PS(&actim_ctrla, 12, 14, tRCD, l3_rate);
248 SDRC_SET_ONE_PS(&actim_ctrla, 15, 17, tRP, l3_rate);
249 SDRC_SET_ONE_PS(&actim_ctrla, 18, 21, tRAS, l3_rate);
250 SDRC_SET_ONE_PS(&actim_ctrla, 22, 26, tRC, l3_rate);
251 SDRC_SET_ONE_PS(&actim_ctrla, 27, 31, tRFC, l3_rate);
253 SDRC_SET_ONE_PS(&actim_ctrlb, 0, 7, tXSR, l3_rate);
255 SDRC_SET_ONE(&actim_ctrlb, 8, 10, tXP, l3_rate);
256 SDRC_SET_ONE(&actim_ctrlb, 12, 14, tCKE, l3_rate);
257 SDRC_SET_ONE(&actim_ctrlb, 16, 17, tWTR, l3_rate);
259 ticks_per_ms = l3_rate;
260 rfr = memory_timings[0].tREF * ticks_per_ms / 1000000;
261 if (rfr > 65535 + 50)
267 printk(KERN_INFO "SDRC tREF: %i ticks\n", rfr);
271 rfr_ctrl = l | 0x1; /* autorefresh, reload counter with 1xARCV */
273 nokia_sdrc_params[id].rate = rate;
274 nokia_sdrc_params[id].actim_ctrla = actim_ctrla;
275 nokia_sdrc_params[id].actim_ctrlb = actim_ctrlb;
276 nokia_sdrc_params[id].rfr_ctrl = rfr_ctrl;
277 nokia_sdrc_params[id].mr = 0x32;
279 nokia_sdrc_params[id + 1].rate = 0;
284 struct omap_sdrc_params *nokia_get_sdram_timings(void)
289 for (i = 0; i < ARRAY_SIZE(nokia_timings); i++) {
290 err |= sdrc_timings(i, nokia_timings[i].rate,
291 nokia_timings[i].data);
293 pr_err("%s: error with rate %ld: %d\n", __func__,
294 nokia_timings[i].rate, err);
297 return err ? NULL : nokia_sdrc_params;