sdram-nokia.c 4.8 KB
Newer Older
T
Tero Kristo 已提交
1
/*
2
 * SDRC register values for Nokia boards
T
Tero Kristo 已提交
3
 *
4
 * Copyright (C) 2008, 2010 Nokia Corporation
T
Tero Kristo 已提交
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45
 *
 * 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;
};

46
static struct omap_sdrc_params nokia_sdrc_params[4];
T
Tero Kristo 已提交
47

48
static const struct sdram_timings memory_timings[] = {
T
Tero Kristo 已提交
49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112
	{
		.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), \
113
			memory_timings->field, (rate), #field) < 0) \
T
Tero Kristo 已提交
114 115 116 117
		err = -1;
#else
#define SDRC_SET_ONE(reg, st, end, field, rate) \
	if (set_sdrc_timing_regval((reg), (st), (end), \
118
			memory_timings->field) < 0) \
T
Tero Kristo 已提交
119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150
		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), \
151
			memory_timings->field, \
T
Tero Kristo 已提交
152 153 154 155 156 157
			(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), \
158
			memory_timings->field, (rate)) < 0) \
T
Tero Kristo 已提交
159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186
		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;
187
	rfr = memory_timings[0].tREF * ticks_per_ms / 1000000;
T
Tero Kristo 已提交
188 189 190 191 192 193 194 195 196 197 198 199
	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 */

200 201 202 203 204
	nokia_sdrc_params[id].rate = rate;
	nokia_sdrc_params[id].actim_ctrla = actim_ctrla;
	nokia_sdrc_params[id].actim_ctrlb = actim_ctrlb;
	nokia_sdrc_params[id].rfr_ctrl = rfr_ctrl;
	nokia_sdrc_params[id].mr = 0x32;
T
Tero Kristo 已提交
205

206
	nokia_sdrc_params[id + 1].rate = 0;
T
Tero Kristo 已提交
207 208 209 210

	return err;
}

211
struct omap_sdrc_params *nokia_get_sdram_timings(void)
T
Tero Kristo 已提交
212 213 214 215 216 217 218
{
	int err;

	err = sdrc_timings(0, 41500000);
	err |= sdrc_timings(1, 83000000);
	err |= sdrc_timings(2, 166000000);

219
	return &nokia_sdrc_params[0];
T
Tero Kristo 已提交
220 221
}