linux/arch/arm/mach-omap2/gpmc-onenand.c
Afzal Mohammed 4f4426f900 ARM: OMAP2+: onenand: generic timing calculation
Generic gpmc timing calculation helper is available now, use
it instead of custom timing calculation.

Signed-off-by: Afzal Mohammed <afzal@ti.com>
2012-11-09 18:07:12 +05:30

394 lines
9.4 KiB
C

/*
* linux/arch/arm/mach-omap2/gpmc-onenand.c
*
* Copyright (C) 2006 - 2009 Nokia Corporation
* Contacts: Juha Yrjola
* Tony Lindgren
*
* 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/string.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/mtd/onenand_regs.h>
#include <linux/io.h>
#include <linux/platform_data/mtd-onenand-omap2.h>
#include <linux/err.h>
#include <asm/mach/flash.h>
#include "gpmc.h"
#include "soc.h"
#include "gpmc-onenand.h"
#define ONENAND_IO_SIZE SZ_128K
#define ONENAND_FLAG_SYNCREAD (1 << 0)
#define ONENAND_FLAG_SYNCWRITE (1 << 1)
#define ONENAND_FLAG_HF (1 << 2)
#define ONENAND_FLAG_VHF (1 << 3)
static unsigned onenand_flags;
static unsigned latency;
static struct omap_onenand_platform_data *gpmc_onenand_data;
static struct resource gpmc_onenand_resource = {
.flags = IORESOURCE_MEM,
};
static struct platform_device gpmc_onenand_device = {
.name = "omap2-onenand",
.id = -1,
.num_resources = 1,
.resource = &gpmc_onenand_resource,
};
static struct gpmc_timings omap2_onenand_calc_async_timings(void)
{
struct gpmc_device_timings dev_t;
struct gpmc_timings t;
const int t_cer = 15;
const int t_avdp = 12;
const int t_aavdh = 7;
const int t_ce = 76;
const int t_aa = 76;
const int t_oe = 20;
const int t_cez = 20; /* max of t_cez, t_oez */
const int t_wpl = 40;
const int t_wph = 30;
memset(&dev_t, 0, sizeof(dev_t));
dev_t.mux = true;
dev_t.t_avdp_r = max_t(int, t_avdp, t_cer) * 1000;
dev_t.t_avdp_w = dev_t.t_avdp_r;
dev_t.t_aavdh = t_aavdh * 1000;
dev_t.t_aa = t_aa * 1000;
dev_t.t_ce = t_ce * 1000;
dev_t.t_oe = t_oe * 1000;
dev_t.t_cez_r = t_cez * 1000;
dev_t.t_cez_w = dev_t.t_cez_r;
dev_t.t_wpl = t_wpl * 1000;
dev_t.t_wph = t_wph * 1000;
gpmc_calc_timings(&t, &dev_t);
return t;
}
static int gpmc_set_async_mode(int cs, struct gpmc_timings *t)
{
/* Configure GPMC for asynchronous read */
gpmc_cs_write_reg(cs, GPMC_CS_CONFIG1,
GPMC_CONFIG1_DEVICESIZE_16 |
GPMC_CONFIG1_MUXADDDATA);
return gpmc_cs_set_timings(cs, t);
}
static void omap2_onenand_set_async_mode(void __iomem *onenand_base)
{
u32 reg;
/* Ensure sync read and sync write are disabled */
reg = readw(onenand_base + ONENAND_REG_SYS_CFG1);
reg &= ~ONENAND_SYS_CFG1_SYNC_READ & ~ONENAND_SYS_CFG1_SYNC_WRITE;
writew(reg, onenand_base + ONENAND_REG_SYS_CFG1);
}
static void set_onenand_cfg(void __iomem *onenand_base)
{
u32 reg;
reg = readw(onenand_base + ONENAND_REG_SYS_CFG1);
reg &= ~((0x7 << ONENAND_SYS_CFG1_BRL_SHIFT) | (0x7 << 9));
reg |= (latency << ONENAND_SYS_CFG1_BRL_SHIFT) |
ONENAND_SYS_CFG1_BL_16;
if (onenand_flags & ONENAND_FLAG_SYNCREAD)
reg |= ONENAND_SYS_CFG1_SYNC_READ;
else
reg &= ~ONENAND_SYS_CFG1_SYNC_READ;
if (onenand_flags & ONENAND_FLAG_SYNCWRITE)
reg |= ONENAND_SYS_CFG1_SYNC_WRITE;
else
reg &= ~ONENAND_SYS_CFG1_SYNC_WRITE;
if (onenand_flags & ONENAND_FLAG_HF)
reg |= ONENAND_SYS_CFG1_HF;
else
reg &= ~ONENAND_SYS_CFG1_HF;
if (onenand_flags & ONENAND_FLAG_VHF)
reg |= ONENAND_SYS_CFG1_VHF;
else
reg &= ~ONENAND_SYS_CFG1_VHF;
writew(reg, onenand_base + ONENAND_REG_SYS_CFG1);
}
static int omap2_onenand_get_freq(struct omap_onenand_platform_data *cfg,
void __iomem *onenand_base)
{
u16 ver = readw(onenand_base + ONENAND_REG_VERSION_ID);
int freq;
switch ((ver >> 4) & 0xf) {
case 0:
freq = 40;
break;
case 1:
freq = 54;
break;
case 2:
freq = 66;
break;
case 3:
freq = 83;
break;
case 4:
freq = 104;
break;
default:
freq = 54;
break;
}
return freq;
}
static struct gpmc_timings
omap2_onenand_calc_sync_timings(struct omap_onenand_platform_data *cfg,
int freq)
{
struct gpmc_device_timings dev_t;
struct gpmc_timings t;
const int t_cer = 15;
const int t_avdp = 12;
const int t_cez = 20; /* max of t_cez, t_oez */
const int t_wpl = 40;
const int t_wph = 30;
int min_gpmc_clk_period, t_ces, t_avds, t_avdh, t_ach, t_aavdh, t_rdyo;
int div, gpmc_clk_ns;
if (cfg->flags & ONENAND_SYNC_READ)
onenand_flags = ONENAND_FLAG_SYNCREAD;
else if (cfg->flags & ONENAND_SYNC_READWRITE)
onenand_flags = ONENAND_FLAG_SYNCREAD | ONENAND_FLAG_SYNCWRITE;
switch (freq) {
case 104:
min_gpmc_clk_period = 9600; /* 104 MHz */
t_ces = 3;
t_avds = 4;
t_avdh = 2;
t_ach = 3;
t_aavdh = 6;
t_rdyo = 6;
break;
case 83:
min_gpmc_clk_period = 12000; /* 83 MHz */
t_ces = 5;
t_avds = 4;
t_avdh = 2;
t_ach = 6;
t_aavdh = 6;
t_rdyo = 9;
break;
case 66:
min_gpmc_clk_period = 15000; /* 66 MHz */
t_ces = 6;
t_avds = 5;
t_avdh = 2;
t_ach = 6;
t_aavdh = 6;
t_rdyo = 11;
break;
default:
min_gpmc_clk_period = 18500; /* 54 MHz */
t_ces = 7;
t_avds = 7;
t_avdh = 7;
t_ach = 9;
t_aavdh = 7;
t_rdyo = 15;
onenand_flags &= ~ONENAND_FLAG_SYNCWRITE;
break;
}
div = gpmc_calc_divider(min_gpmc_clk_period);
gpmc_clk_ns = gpmc_ticks_to_ns(div);
if (gpmc_clk_ns < 15) /* >66Mhz */
onenand_flags |= ONENAND_FLAG_HF;
else
onenand_flags &= ~ONENAND_FLAG_HF;
if (gpmc_clk_ns < 12) /* >83Mhz */
onenand_flags |= ONENAND_FLAG_VHF;
else
onenand_flags &= ~ONENAND_FLAG_VHF;
if (onenand_flags & ONENAND_FLAG_VHF)
latency = 8;
else if (onenand_flags & ONENAND_FLAG_HF)
latency = 6;
else if (gpmc_clk_ns >= 25) /* 40 MHz*/
latency = 3;
else
latency = 4;
/* Set synchronous read timings */
memset(&dev_t, 0, sizeof(dev_t));
dev_t.mux = true;
dev_t.sync_read = true;
if (onenand_flags & ONENAND_FLAG_SYNCWRITE) {
dev_t.sync_write = true;
} else {
dev_t.t_avdp_w = max(t_avdp, t_cer) * 1000;
dev_t.t_wpl = t_wpl * 1000;
dev_t.t_wph = t_wph * 1000;
dev_t.t_aavdh = t_aavdh * 1000;
}
dev_t.ce_xdelay = true;
dev_t.avd_xdelay = true;
dev_t.oe_xdelay = true;
dev_t.we_xdelay = true;
dev_t.clk = min_gpmc_clk_period;
dev_t.t_bacc = dev_t.clk;
dev_t.t_ces = t_ces * 1000;
dev_t.t_avds = t_avds * 1000;
dev_t.t_avdh = t_avdh * 1000;
dev_t.t_ach = t_ach * 1000;
dev_t.cyc_iaa = (latency + 1);
dev_t.t_cez_r = t_cez * 1000;
dev_t.t_cez_w = dev_t.t_cez_r;
dev_t.cyc_aavdh_oe = 1;
dev_t.t_rdyo = t_rdyo * 1000 + min_gpmc_clk_period;
gpmc_calc_timings(&t, &dev_t);
return t;
}
static int gpmc_set_sync_mode(int cs, struct gpmc_timings *t)
{
unsigned sync_read = onenand_flags & ONENAND_FLAG_SYNCREAD;
unsigned sync_write = onenand_flags & ONENAND_FLAG_SYNCWRITE;
/* Configure GPMC for synchronous read */
gpmc_cs_write_reg(cs, GPMC_CS_CONFIG1,
GPMC_CONFIG1_WRAPBURST_SUPP |
GPMC_CONFIG1_READMULTIPLE_SUPP |
(sync_read ? GPMC_CONFIG1_READTYPE_SYNC : 0) |
(sync_write ? GPMC_CONFIG1_WRITEMULTIPLE_SUPP : 0) |
(sync_write ? GPMC_CONFIG1_WRITETYPE_SYNC : 0) |
GPMC_CONFIG1_PAGE_LEN(2) |
(cpu_is_omap34xx() ? 0 :
(GPMC_CONFIG1_WAIT_READ_MON |
GPMC_CONFIG1_WAIT_PIN_SEL(0))) |
GPMC_CONFIG1_DEVICESIZE_16 |
GPMC_CONFIG1_DEVICETYPE_NOR |
GPMC_CONFIG1_MUXADDDATA);
return gpmc_cs_set_timings(cs, t);
}
static int omap2_onenand_setup_async(void __iomem *onenand_base)
{
struct gpmc_timings t;
int ret;
omap2_onenand_set_async_mode(onenand_base);
t = omap2_onenand_calc_async_timings();
ret = gpmc_set_async_mode(gpmc_onenand_data->cs, &t);
if (IS_ERR_VALUE(ret))
return ret;
omap2_onenand_set_async_mode(onenand_base);
return 0;
}
static int omap2_onenand_setup_sync(void __iomem *onenand_base, int *freq_ptr)
{
int ret, freq = *freq_ptr;
struct gpmc_timings t;
if (!freq) {
/* Very first call freq is not known */
freq = omap2_onenand_get_freq(gpmc_onenand_data, onenand_base);
set_onenand_cfg(onenand_base);
}
t = omap2_onenand_calc_sync_timings(gpmc_onenand_data, freq);
ret = gpmc_set_sync_mode(gpmc_onenand_data->cs, &t);
if (IS_ERR_VALUE(ret))
return ret;
set_onenand_cfg(onenand_base);
*freq_ptr = freq;
return 0;
}
static int gpmc_onenand_setup(void __iomem *onenand_base, int *freq_ptr)
{
struct device *dev = &gpmc_onenand_device.dev;
unsigned l = ONENAND_SYNC_READ | ONENAND_SYNC_READWRITE;
int ret;
ret = omap2_onenand_setup_async(onenand_base);
if (ret) {
dev_err(dev, "unable to set to async mode\n");
return ret;
}
if (!(gpmc_onenand_data->flags & l))
return 0;
ret = omap2_onenand_setup_sync(onenand_base, freq_ptr);
if (ret)
dev_err(dev, "unable to set to sync mode\n");
return ret;
}
void __init gpmc_onenand_init(struct omap_onenand_platform_data *_onenand_data)
{
int err;
gpmc_onenand_data = _onenand_data;
gpmc_onenand_data->onenand_setup = gpmc_onenand_setup;
gpmc_onenand_device.dev.platform_data = gpmc_onenand_data;
if (cpu_is_omap24xx() &&
(gpmc_onenand_data->flags & ONENAND_SYNC_READWRITE)) {
printk(KERN_ERR "Onenand using only SYNC_READ on 24xx\n");
gpmc_onenand_data->flags &= ~ONENAND_SYNC_READWRITE;
gpmc_onenand_data->flags |= ONENAND_SYNC_READ;
}
if (cpu_is_omap34xx())
gpmc_onenand_data->flags |= ONENAND_IN_OMAP34XX;
else
gpmc_onenand_data->flags &= ~ONENAND_IN_OMAP34XX;
err = gpmc_cs_request(gpmc_onenand_data->cs, ONENAND_IO_SIZE,
(unsigned long *)&gpmc_onenand_resource.start);
if (err < 0) {
pr_err("%s: Cannot request GPMC CS\n", __func__);
return;
}
gpmc_onenand_resource.end = gpmc_onenand_resource.start +
ONENAND_IO_SIZE - 1;
if (platform_device_register(&gpmc_onenand_device) < 0) {
pr_err("%s: Unable to register OneNAND device\n", __func__);
gpmc_cs_free(gpmc_onenand_data->cs);
return;
}
}