ar71xx: add NAND driver for the Mikrotik RB91x boards

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>

SVN-Revision: 39097
lede-17.01
Gabor Juhos 2013-12-16 12:57:24 +00:00
parent d7a0184446
commit 8461ffccc1
2 changed files with 378 additions and 0 deletions

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@ -0,0 +1,355 @@
/*
* NAND flash driver for the MikroTik RouterBOARD 91x series
*
* Copyright (C) 2013 Gabor Juhos <juhosg@openwrt.org>
*
* 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/spinlock.h>
#include <linux/module.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <asm/mach-ath79/ar71xx_regs.h>
#include <asm/mach-ath79/ath79.h>
#define DRV_NAME "rb91x-nand"
#define DRV_DESC "NAND flash driver for the RouterBOARD 91x series"
#define RB91X_NAND_NRE_ENABLE BIT(3)
#define RB91X_NAND_RDY BIT(4)
#define RB91X_LATCH_ENABLE BIT(11)
#define RB91X_NAND_NRWE BIT(12)
#define RB91X_NAND_NCE BIT(13)
#define RB91X_NAND_CLE BIT(14)
#define RB91X_NAND_ALE BIT(15)
#define RB91X_NAND_DATA_BITS (BIT(0) | BIT(1) | BIT(2) | BIT(3) | BIT(4) |\
BIT(13) | BIT(14) | BIT(15))
#define RB91X_NAND_INPUT_BITS (RB91X_NAND_DATA_BITS | RB91X_NAND_RDY)
#define RB91X_NAND_OUTPUT_BITS \
(RB91X_NAND_DATA_BITS | RB91X_NAND_NRWE)
#define RB91X_NAND_LOW_DATA_MASK 0x1f
#define RB91X_NAND_HIGH_DATA_MASK 0xe0
#define RB91X_NAND_HIGH_DATA_SHIFT 8
struct rb91x_nand_info {
struct nand_chip chip;
struct mtd_info mtd;
};
static inline struct rb91x_nand_info *mtd_to_rbinfo(struct mtd_info *mtd)
{
return container_of(mtd, struct rb91x_nand_info, mtd);
}
/*
* We need to use the OLD Yaffs-1 OOB layout, otherwise the RB bootloader
* will not be able to find the kernel that we load.
*/
static struct nand_ecclayout rb91x_nand_ecclayout = {
.eccbytes = 6,
.eccpos = { 8, 9, 10, 13, 14, 15 },
.oobavail = 9,
.oobfree = { { 0, 4 }, { 6, 2 }, { 11, 2 }, { 4, 1 } }
};
static struct mtd_partition rb91x_nand_partitions[] = {
{
.name = "booter",
.offset = 0,
.size = (256 * 1024),
.mask_flags = MTD_WRITEABLE,
}, {
.name = "kernel",
.offset = (256 * 1024),
.size = (4 * 1024 * 1024) - (256 * 1024),
}, {
.name = "rootfs",
.offset = MTDPART_OFS_NXTBLK,
.size = MTDPART_SIZ_FULL,
},
};
static void rb91x_change_gpo(u32 clear, u32 set)
{
void __iomem *base = ath79_gpio_base;
static unsigned on = 0xE002800;
static unsigned off = 0x0000C008;
static unsigned oe = 0;
static DEFINE_SPINLOCK(lock);
unsigned long flags;
spin_lock_irqsave(&lock, flags);
on = (on | set) & ~clear;
off = (off | clear) & ~set;
if (!oe)
oe = __raw_readl(base + AR71XX_GPIO_REG_OE);
if (on & RB91X_LATCH_ENABLE) {
u32 t;
t = oe & __raw_readl(base + AR71XX_GPIO_REG_OE);
t &= ~(on | off);
__raw_writel(t, base + AR71XX_GPIO_REG_OE);
__raw_writel(off, base + AR71XX_GPIO_REG_CLEAR);
__raw_writel(on, base + AR71XX_GPIO_REG_SET);
} else if (clear & RB91X_LATCH_ENABLE) {
oe = __raw_readl(base + AR71XX_GPIO_REG_OE);
__raw_writel(RB91X_LATCH_ENABLE,
base + AR71XX_GPIO_REG_CLEAR);
/* flush write */
__raw_readl(base + AR71XX_GPIO_REG_CLEAR);
}
spin_unlock_irqrestore(&lock, flags);
}
static inline void rb91x_latch_enable(void)
{
rb91x_change_gpo(RB91X_LATCH_ENABLE, 0);
}
static inline void rb91x_latch_disable(void)
{
rb91x_change_gpo(0, RB91X_LATCH_ENABLE);
}
static void rb91x_nand_write(const u8 *buf, unsigned len)
{
void __iomem *base = ath79_gpio_base;
u32 oe_reg;
u32 out_reg;
u32 out;
unsigned i;
rb91x_latch_enable();
oe_reg = __raw_readl(base + AR71XX_GPIO_REG_OE);
out_reg = __raw_readl(base + AR71XX_GPIO_REG_OUT);
/* set data lines to output mode */
__raw_writel(oe_reg & ~(RB91X_NAND_DATA_BITS | RB91X_NAND_NRWE),
base + AR71XX_GPIO_REG_OE);
out = out_reg & ~(RB91X_NAND_DATA_BITS | RB91X_NAND_NRWE);
for (i = 0; i != len; i++) {
u32 data;
data = (buf[i] & RB91X_NAND_HIGH_DATA_MASK) <<
RB91X_NAND_HIGH_DATA_SHIFT;
data |= buf[i] & RB91X_NAND_LOW_DATA_MASK;
data |= out;
__raw_writel(data, base + AR71XX_GPIO_REG_OUT);
/* deactivate WE line */
data |= RB91X_NAND_NRWE;
__raw_writel(data, base + AR71XX_GPIO_REG_OUT);
/* flush write */
__raw_readl(base + AR71XX_GPIO_REG_OUT);
}
/* restore registers */
__raw_writel(oe_reg, base + AR71XX_GPIO_REG_OE);
__raw_writel(out_reg, base + AR71XX_GPIO_REG_OUT);
/* flush write */
__raw_readl(base + AR71XX_GPIO_REG_OUT);
rb91x_latch_disable();
}
static void rb91x_nand_read(u8 *read_buf, unsigned len)
{
void __iomem *base = ath79_gpio_base;
u32 oe_reg;
u32 out_reg;
unsigned i;
/* save registers */
oe_reg = __raw_readl(base + AR71XX_GPIO_REG_OE);
/* select nRE mode */
rb91x_change_gpo(0, RB91X_NAND_NRE_ENABLE);
/* enable latch */
rb91x_latch_enable();
out_reg = __raw_readl(base + AR71XX_GPIO_REG_OUT);
/* set data lines to input mode */
__raw_writel(oe_reg | RB91X_NAND_DATA_BITS,
base + AR71XX_GPIO_REG_OE);
for (i = 0; i < len; i++) {
u32 in;
u8 data;
/* activate RE line */
__raw_writel(RB91X_NAND_NRWE, base + AR71XX_GPIO_REG_CLEAR);
/* flush write */
__raw_readl(base + AR71XX_GPIO_REG_CLEAR);
/* read input lines */
in = __raw_readl(base + AR71XX_GPIO_REG_IN);
/* deactivate RE line */
__raw_writel(RB91X_NAND_NRWE, base + AR71XX_GPIO_REG_SET);
data = (in & RB91X_NAND_LOW_DATA_MASK);
data |= (in >> RB91X_NAND_HIGH_DATA_SHIFT) &
RB91X_NAND_HIGH_DATA_MASK;
read_buf[i] = data;
}
/* restore registers */
__raw_writel(oe_reg, base + AR71XX_GPIO_REG_OE);
__raw_writel(out_reg, base + AR71XX_GPIO_REG_OUT);
/* flush write */
__raw_readl(base + AR71XX_GPIO_REG_OUT);
/* disable latch */
rb91x_latch_disable();
/* deselect nRE mode */
rb91x_change_gpo(RB91X_NAND_NRE_ENABLE, 0);
}
static int rb91x_nand_dev_ready(struct mtd_info *mtd)
{
void __iomem *base = ath79_gpio_base;
return !!(__raw_readl(base + AR71XX_GPIO_REG_IN) & RB91X_NAND_RDY);
}
static void rb91x_nand_cmd_ctrl(struct mtd_info *mtd, int cmd,
unsigned int ctrl)
{
if (ctrl & NAND_CTRL_CHANGE) {
u32 on = 0;
u32 off;
if (!(ctrl & NAND_NCE))
on |= RB91X_NAND_NCE;
if (ctrl & NAND_CLE)
on |= RB91X_NAND_CLE;
if (ctrl & NAND_ALE)
on |= RB91X_NAND_ALE;
off = on ^ (RB91X_NAND_ALE | RB91X_NAND_NCE | RB91X_NAND_CLE);
rb91x_change_gpo(off, on);
}
if (cmd != NAND_CMD_NONE) {
u8 t = cmd;
rb91x_nand_write(&t, 1);
}
}
static u8 rb91x_nand_read_byte(struct mtd_info *mtd)
{
u8 data = 0xff;
rb91x_nand_read(&data, 1);
return data;
}
static void rb91x_nand_read_buf(struct mtd_info *mtd, u8 *buf, int len)
{
rb91x_nand_read(buf, len);
}
static void rb91x_nand_write_buf(struct mtd_info *mtd, const u8 *buf, int len)
{
rb91x_nand_write(buf, len);
}
static int rb91x_nand_probe(struct platform_device *pdev)
{
struct rb91x_nand_info *info;
int ret;
pr_info(DRV_DESC "\n");
info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
if (!info)
return -ENOMEM;
info->chip.priv = &info;
info->mtd.priv = &info->chip;
info->mtd.owner = THIS_MODULE;
info->chip.cmd_ctrl = rb91x_nand_cmd_ctrl;
info->chip.dev_ready = rb91x_nand_dev_ready;
info->chip.read_byte = rb91x_nand_read_byte;
info->chip.write_buf = rb91x_nand_write_buf;
info->chip.read_buf = rb91x_nand_read_buf;
info->chip.chip_delay = 25;
info->chip.ecc.mode = NAND_ECC_SOFT;
platform_set_drvdata(pdev, info);
ret = nand_scan_ident(&info->mtd, 1, NULL);
if (ret)
return ret;
if (info->mtd.writesize == 512)
info->chip.ecc.layout = &rb91x_nand_ecclayout;
ret = nand_scan_tail(&info->mtd);
if (ret)
return ret;
ret = mtd_device_register(&info->mtd, rb91x_nand_partitions,
ARRAY_SIZE(rb91x_nand_partitions));
if (ret)
goto err_release_nand;
return 0;
err_release_nand:
nand_release(&info->mtd);
return ret;
}
static int rb91x_nand_remove(struct platform_device *pdev)
{
struct rb91x_nand_info *info = platform_get_drvdata(pdev);
nand_release(&info->mtd);
return 0;
}
static struct platform_driver rb91x_nand_driver = {
.probe = rb91x_nand_probe,
.remove = rb91x_nand_remove,
.driver = {
.name = DRV_NAME,
.owner = THIS_MODULE,
},
};
module_platform_driver(rb91x_nand_driver);
MODULE_DESCRIPTION(DRV_DESC);
MODULE_VERSION(DRV_VERSION);
MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
MODULE_LICENSE("GPL v2");

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@ -0,0 +1,23 @@
--- a/drivers/mtd/nand/Kconfig
+++ b/drivers/mtd/nand/Kconfig
@@ -552,6 +552,10 @@ config MTD_NAND_RB750
tristate "NAND flash driver for the RouterBoard 750"
depends on MTD_NAND && ATH79_MACH_RB750
+config MTD_NAND_RB91X
+ tristate "NAND flash driver for the RouterBOARD 91x series"
+ depends on MTD_NAND && ATH79_MACH_RB91X
+
config MTD_NAND_AR934X
tristate "NAND flash driver for the Qualcomm Atheros AR934x/QCA955x SoCs"
depends on (SOC_AR934X || SOC_QCA955X)
--- a/drivers/mtd/nand/Makefile
+++ b/drivers/mtd/nand/Makefile
@@ -34,6 +34,7 @@ obj-$(CONFIG_MTD_NAND_TMIO) += tmio_nan
obj-$(CONFIG_MTD_NAND_PLATFORM) += plat_nand.o
obj-$(CONFIG_MTD_NAND_RB4XX) += rb4xx_nand.o
obj-$(CONFIG_MTD_NAND_RB750) += rb750_nand.o
+obj-$(CONFIG_MTD_NAND_RB91X) += rb91x_nand.o
obj-$(CONFIG_MTD_ALAUDA) += alauda.o
obj-$(CONFIG_MTD_NAND_PASEMI) += pasemi_nand.o
obj-$(CONFIG_MTD_NAND_ORION) += orion_nand.o