- 根目录:
- drivers
- mtd
- devices
- spear_smi.c
/*
* SMI (Serial Memory Controller) device driver for Serial NOR Flash on
* SPEAr platform
* The serial nor interface is largely based on drivers/mtd/m25p80.c,
* however the SPI interface has been replaced by SMI.
*
* Copyright © 2010 STMicroelectronics.
* Ashish Priyadarshi
* Shiraz Hashim <shiraz.linux.kernel@gmail.com>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/param.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#include <linux/mtd/spear_smi.h>
#include <linux/mutex.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/wait.h>
#include <linux/of.h>
#include <linux/of_address.h>
/* SMI clock rate */
#define SMI_MAX_CLOCK_FREQ 50000000 /* 50 MHz */
/* MAX time out to safely come out of a erase or write busy conditions */
#define SMI_PROBE_TIMEOUT (HZ / 10)
#define SMI_MAX_TIME_OUT (3 * HZ)
/* timeout for command completion */
#define SMI_CMD_TIMEOUT (HZ / 10)
/* registers of smi */
#define SMI_CR1 0x0 /* SMI control register 1 */
#define SMI_CR2 0x4 /* SMI control register 2 */
#define SMI_SR 0x8 /* SMI status register */
#define SMI_TR 0xC /* SMI transmit register */
#define SMI_RR 0x10 /* SMI receive register */
/* defines for control_reg 1 */
#define BANK_EN (0xF << 0) /* enables all banks */
#define DSEL_TIME (0x6 << 4) /* Deselect time 6 + 1 SMI_CK periods */
#define SW_MODE (0x1 << 28) /* enables SW Mode */
#define WB_MODE (0x1 << 29) /* Write Burst Mode */
#define FAST_MODE (0x1 << 15) /* Fast Mode */
#define HOLD1 (0x1 << 16) /* Clock Hold period selection */
/* defines for control_reg 2 */
#define SEND (0x1 << 7) /* Send data */
#define TFIE (0x1 << 8) /* Transmission Flag Interrupt Enable */
#define WCIE (0x1 << 9) /* Write Complete Interrupt Enable */
#define RD_STATUS_REG (0x1 << 10) /* reads status reg */
#define WE (0x1 << 11) /* Write Enable */
#define TX_LEN_SHIFT 0
#define RX_LEN_SHIFT 4
#define BANK_SHIFT 12
/* defines for status register */
#define SR_WIP 0x1 /* Write in progress */
#define SR_WEL 0x2 /* Write enable latch */
#define SR_BP0 0x4 /* Block protect 0 */
#define SR_BP1 0x8 /* Block protect 1 */
#define SR_BP2 0x10 /* Block protect 2 */
#define SR_SRWD 0x80 /* SR write protect */
#define TFF 0x100 /* Transfer Finished Flag */
#define WCF 0x200 /* Transfer Finished Flag */
#define ERF1 0x400 /* Forbidden Write Request */
#define ERF2 0x800 /* Forbidden Access */
#define WM_SHIFT 12
/* flash opcodes */
#define OPCODE_RDID 0x9f /* Read JEDEC ID */
/* Flash Device Ids maintenance section */
/* data structure to maintain flash ids from different vendors */
struct flash_device {
char *name;
u8 erase_cmd;
u32 device_id;
u32 pagesize;
unsigned long sectorsize;
unsigned long size_in_bytes;
};
#define FLASH_ID(n, es, id, psize, ssize, size) \
{ \
.name = n, \
.erase_cmd = es, \
.device_id = id, \
.pagesize = psize, \
.sectorsize = ssize, \
.size_in_bytes = size \
}
static struct flash_device flash_devices[] = {
FLASH_ID("st m25p16" , 0xd8, 0x00152020, 0x100, 0x10000, 0x200000),
FLASH_ID("st m25p32" , 0xd8, 0x00162020, 0x100, 0x10000, 0x400000),
FLASH_ID("st m25p64" , 0xd8, 0x00172020, 0x100, 0x10000, 0x800000),
FLASH_ID("st m25p128" , 0xd8, 0x00182020, 0x100, 0x40000, 0x1000000),
FLASH_ID("st m25p05" , 0xd8, 0x00102020, 0x80 , 0x8000 , 0x10000),
FLASH_ID("st m25p10" , 0xd8, 0x00112020, 0x80 , 0x8000 , 0x20000),
FLASH_ID("st m25p20" , 0xd8, 0x00122020, 0x100, 0x10000, 0x40000),
FLASH_ID("st m25p40" , 0xd8, 0x00132020, 0x100, 0x10000, 0x80000),
FLASH_ID("st m25p80" , 0xd8, 0x00142020, 0x100, 0x10000, 0x100000),
FLASH_ID("st m45pe10" , 0xd8, 0x00114020, 0x100, 0x10000, 0x20000),
FLASH_ID("st m45pe20" , 0xd8, 0x00124020, 0x100, 0x10000, 0x40000),
FLASH_ID("st m45pe40" , 0xd8, 0x00134020, 0x100, 0x10000, 0x80000),
FLASH_ID("st m45pe80" , 0xd8, 0x00144020, 0x100, 0x10000, 0x100000),
FLASH_ID("sp s25fl004" , 0xd8, 0x00120201, 0x100, 0x10000, 0x80000),
FLASH_ID("sp s25fl008" , 0xd8, 0x00130201, 0x100, 0x10000, 0x100000),
FLASH_ID("sp s25fl016" , 0xd8, 0x00140201, 0x100, 0x10000, 0x200000),
FLASH_ID("sp s25fl032" , 0xd8, 0x00150201, 0x100, 0x10000, 0x400000),
FLASH_ID("sp s25fl064" , 0xd8, 0x00160201, 0x100, 0x10000, 0x800000),
FLASH_ID("atmel 25f512" , 0x52, 0x0065001F, 0x80 , 0x8000 , 0x10000),
FLASH_ID("atmel 25f1024" , 0x52, 0x0060001F, 0x100, 0x8000 , 0x20000),
FLASH_ID("atmel 25f2048" , 0x52, 0x0063001F, 0x100, 0x10000, 0x40000),
FLASH_ID("atmel 25f4096" , 0x52, 0x0064001F, 0x100, 0x10000, 0x80000),
FLASH_ID("atmel 25fs040" , 0xd7, 0x0004661F, 0x100, 0x10000, 0x80000),
FLASH_ID("mac 25l512" , 0xd8, 0x001020C2, 0x010, 0x10000, 0x10000),
FLASH_ID("mac 25l1005" , 0xd8, 0x001120C2, 0x010, 0x10000, 0x20000),
FLASH_ID("mac 25l2005" , 0xd8, 0x001220C2, 0x010, 0x10000, 0x40000),
FLASH_ID("mac 25l4005" , 0xd8, 0x001320C2, 0x010, 0x10000, 0x80000),
FLASH_ID("mac 25l4005a" , 0xd8, 0x001320C2, 0x010, 0x10000, 0x80000),
FLASH_ID("mac 25l8005" , 0xd8, 0x001420C2, 0x010, 0x10000, 0x100000),
FLASH_ID("mac 25l1605" , 0xd8, 0x001520C2, 0x100, 0x10000, 0x200000),
FLASH_ID("mac 25l1605a" , 0xd8, 0x001520C2, 0x010, 0x10000, 0x200000),
FLASH_ID("mac 25l3205" , 0xd8, 0x001620C2, 0x100, 0x10000, 0x400000),
FLASH_ID("mac 25l3205a" , 0xd8, 0x001620C2, 0x100, 0x10000, 0x400000),
FLASH_ID("mac 25l6405" , 0xd8, 0x001720C2, 0x100, 0x10000, 0x800000),
};
/* Define spear specific structures */
struct spear_snor_flash;
/**
* struct spear_smi - Structure for SMI Device
*
* @clk: functional clock
* @status: current status register of SMI.
* @clk_rate: functional clock rate of SMI (default: SMI_MAX_CLOCK_FREQ)
* @lock: lock to prevent parallel access of SMI.
* @io_base: base address for registers of SMI.
* @pdev: platform device
* @cmd_complete: queue to wait for command completion of NOR-flash.
* @num_flashes: number of flashes actually present on board.
* @flash: separate structure for each Serial NOR-flash attached to SMI.
*/
struct spear_smi {
struct clk *clk;
u32 status;
unsigned long clk_rate;
struct mutex lock;
void __iomem *io_base;
struct platform_device *pdev;
wait_queue_head_t cmd_complete;
u32 num_flashes;
struct spear_snor_flash *flash[MAX_NUM_FLASH_CHIP];
};
/**
* struct spear_snor_flash - Structure for Serial NOR Flash
*
* @bank: Bank number(0, 1, 2, 3) for each NOR-flash.
* @dev_id: Device ID of NOR-flash.
* @lock: lock to manage flash read, write and erase operations
* @mtd: MTD info for each NOR-flash.
* @num_parts: Total number of partition in each bank of NOR-flash.
* @parts: Partition info for each bank of NOR-flash.
* @page_size: Page size of NOR-flash.
* @base_addr: Base address of NOR-flash.
* @erase_cmd: erase command may vary on different flash types
* @fast_mode: flash supports read in fast mode
*/
struct spear_snor_flash {
u32 bank;
u32 dev_id;
struct mutex lock;
struct mtd_info mtd;
u32 num_parts;
struct mtd_partition *parts;
u32 page_size;
void __iomem *base_addr;
u8 erase_cmd;
u8 fast_mode;
};
static inline struct spear_snor_flash *get_flash_data(struct mtd_info *mtd)
{
return container_of(mtd, struct spear_snor_flash, mtd);
}
/**
* spear_smi_read_sr - Read status register of flash through SMI
* @dev: structure of SMI information.
* @bank: bank to which flash is connected
*
* This routine will return the status register of the flash chip present at the
* given bank.
*/
static int spear_smi_read_sr(struct spear_smi *dev, u32 bank)
{
int ret;
u32 ctrlreg1;
mutex_lock(&dev->lock);
dev->status = 0; /* Will be set in interrupt handler */
ctrlreg1 = readl(dev->io_base + SMI_CR1);
/* program smi in hw mode */
writel(ctrlreg1 & ~(SW_MODE | WB_MODE), dev->io_base + SMI_CR1);
/* performing a rsr instruction in hw mode */
writel((bank << BANK_SHIFT) | RD_STATUS_REG | TFIE,
dev->io_base + SMI_CR2);
/* wait for tff */
ret = wait_event_interruptible_timeout(dev->cmd_complete,
dev->status & TFF, SMI_CMD_TIMEOUT);
/* copy dev->status (lower 16 bits) in order to release lock */
if (ret > 0)
ret = dev->status & 0xffff;
else if (ret == 0)
ret = -ETIMEDOUT;
/* restore the ctrl regs state */
writel(ctrlreg1, dev->io_base + SMI_CR1);
writel(0, dev->io_base + SMI_CR2);
mutex_unlock(&dev->lock);
return ret;
}
/**
* spear_smi_wait_till_ready - wait till flash is ready
* @dev: structure of SMI information.
* @bank: flash corresponding to this bank
* @timeout: timeout for busy wait condition
*
* This routine checks for WIP (write in progress) bit in Status register
* If successful the routine returns 0 else -EBUSY
*/
static int spear_smi_wait_till_ready(struct spear_smi *dev, u32 bank,
unsigned long timeout)
{
unsigned long finish;
int status;
finish = jiffies + timeout;
do {
status = spear_smi_read_sr(dev, bank);
if (status < 0) {
if (status == -ETIMEDOUT)
continue; /* try till finish */
return status;
} else if (!(status & SR_WIP)) {
return 0;
}
cond_resched();
} while (!time_after_eq(jiffies, finish));
dev_err(&dev->pdev->dev, "smi controller is busy, timeout\n");
return -EBUSY;
}
/**
* spear_smi_int_handler - SMI Interrupt Handler.
* @irq: irq number
* @dev_id: structure of SMI device, embedded in dev_id.
*
* The handler clears all interrupt conditions and records the status in
* dev->status which is used by the driver later.
*/
static irqreturn_t spear_smi_int_handler(int irq, void *dev_id)
{
u32 status = 0;
struct spear_smi *dev = dev_id;
status = readl(dev->io_base + SMI_SR);
if (unlikely(!status))
return IRQ_NONE;
/* clear all interrupt conditions */
writel(0, dev->io_base + SMI_SR);
/* copy the status register in dev->status */
dev->status |= status;
/* send the completion */
wake_up_interruptible(&dev->cmd_complete);
return IRQ_HANDLED;
}
/**
* spear_smi_hw_init - initializes the smi controller.
* @dev: structure of smi device
*
* this routine initializes the smi controller wit the default values
*/
static void spear_smi_hw_init(struct spear_smi *dev)
{
unsigned long rate = 0;
u32 prescale = 0;
u32 val;
rate = clk_get_rate(dev->clk);
/* functional clock of smi */
prescale = DIV_ROUND_UP(rate, dev->clk_rate);
/*
* setting the standard values, fast mode, prescaler for
* SMI_MAX_CLOCK_FREQ (50MHz) operation and bank enable
*/
val = HOLD1 | BANK_EN | DSEL_TIME | (prescale << 8);
mutex_lock(&dev->lock);
/* clear all interrupt conditions */
writel(0, dev->io_base + SMI_SR);
writel(val, dev->io_base + SMI_CR1);
mutex_unlock(&dev->lock);
}
/**
* get_flash_index - match chip id from a flash list.
* @flash_id: a valid nor flash chip id obtained from board.
*
* try to validate the chip id by matching from a list, if not found then simply
* returns negative. In case of success returns index in to the flash devices
* array.
*/
static int get_flash_index(u32 flash_id)
{
int index;
/* Matches chip-id to entire list of 'serial-nor flash' ids */
for (index = 0; index < ARRAY_SIZE(flash_devices); index++) {
if (flash_devices[index].device_id == flash_id)
return index;
}
/* Memory chip is not listed and not supported */
return -ENODEV;
}
/**
* spear_smi_write_enable - Enable the flash to do write operation
* @dev: structure of SMI device
* @bank: enable write for flash connected to this bank
*
* Set write enable latch with Write Enable command.
* Returns 0 on success.
*/
static int spear_smi_write_enable(struct spear_smi *dev, u32 bank)
{
int ret;
u32 ctrlreg1;
mutex_lock(&dev->lock);
dev->status = 0; /* Will be set in interrupt handler */
ctrlreg1 = readl(dev->io_base + SMI_CR1);
/* program smi in h/w mode */
writel(ctrlreg1 & ~SW_MODE, dev->io_base + SMI_CR1);
/* give the flash, write enable command */
writel((bank << BANK_SHIFT) | WE | TFIE, dev->io_base + SMI_CR2);
ret = wait_event_interruptible_timeout(dev->cmd_complete,
dev->status & TFF, SMI_CMD_TIMEOUT);
/* restore the ctrl regs state */
writel(ctrlreg1, dev->io_base + SMI_CR1);
writel(0, dev->io_base + SMI_CR2);
if (ret == 0) {
ret = -EIO;
dev_err(&dev->pdev->dev,
"smi controller failed on write enable\n");
} else if (ret > 0) {
/* check whether write mode status is set for required bank */
if (dev->status & (1 << (bank + WM_SHIFT)))
ret = 0;
else {
dev_err(&dev->pdev->dev, "couldn't enable write\n");
ret = -EIO;
}
}
mutex_unlock(&dev->lock);
return ret;
}
static inline u32
get_sector_erase_cmd(struct spear_snor_flash *flash, u32 offset)
{
u32 cmd;
u8 *x = (u8 *)&cmd;
x[0] = flash->erase_cmd;
x[1] = offset >> 16;
x[2] = offset >> 8;
x[3] = offset;
return cmd;
}
/**
* spear_smi_erase_sector - erase one sector of flash
* @dev: structure of SMI information
* @command: erase command to be send
* @bank: bank to which this command needs to be send
* @bytes: size of command
*
* Erase one sector of flash memory at offset ``offset'' which is any
* address within the sector which should be erased.
* Returns 0 if successful, non-zero otherwise.
*/
static int spear_smi_erase_sector(struct spear_smi *dev,
u32 bank, u32 command, u32 bytes)
{
u32 ctrlreg1 = 0;
int ret;
ret = spear_smi_wait_till_ready(dev, bank, SMI_MAX_TIME_OUT);
if (ret)
return ret;
ret = spear_smi_write_enable(dev, bank);
if (ret)
return ret;
mutex_lock(&dev->lock);
ctrlreg1 = readl(dev->io_base + SMI_CR1);
writel((ctrlreg1 | SW_MODE) & ~WB_MODE, dev->io_base + SMI_CR1);
/* send command in sw mode */
writel(command, dev->io_base + SMI_TR);
writel((bank << BANK_SHIFT) | SEND | TFIE | (bytes << TX_LEN_SHIFT),
dev->io_base + SMI_CR2);
ret = wait_event_interruptible_timeout(dev->cmd_complete,
dev->status & TFF, SMI_CMD_TIMEOUT);
if (ret == 0) {
ret = -EIO;
dev_err(&dev->pdev->dev, "sector erase failed\n");
} else if (ret > 0)
ret = 0; /* success */
/* restore ctrl regs */
writel(ctrlreg1, dev->io_base + SMI_CR1);
writel(0, dev->io_base + SMI_CR2);
mutex_unlock(&dev->lock);
return ret;
}
/**
* spear_mtd_erase - perform flash erase operation as requested by user
* @mtd: Provides the memory characteristics
* @e_info: Provides the erase information
*
* Erase an address range on the flash chip. The address range may extend
* one or more erase sectors. Return an error is there is a problem erasing.
*/
static int spear_mtd_erase(struct mtd_info *mtd, struct erase_info *e_info)
{
struct spear_snor_flash *flash = get_flash_data(mtd);
struct spear_smi *dev = mtd->priv;
u32 addr, command, bank;
int len, ret;
if (!flash || !dev)
return -ENODEV;
bank = flash->bank;
if (bank > dev->num_flashes - 1) {
dev_err(&dev->pdev->dev, "Invalid Bank Num");
return -EINVAL;
}
addr = e_info->addr;
len = e_info->len;
mutex_lock(&flash->lock);
/* now erase sectors in loop */
while (len) {
command = get_sector_erase_cmd(flash, addr);
/* preparing the command for flash */
ret = spear_smi_erase_sector(dev, bank, command, 4);
if (ret) {
e_info->state = MTD_ERASE_FAILED;
mutex_unlock(&flash->lock);
return ret;
}
addr += mtd->erasesize;
len -= mtd->erasesize;
}
mutex_unlock(&flash->lock);
e_info->state = MTD_ERASE_DONE;
mtd_erase_callback(e_info);
return 0;
}
/**
* spear_mtd_read - performs flash read operation as requested by the user
* @mtd: MTD information of the memory bank
* @from: Address from which to start read
* @len: Number of bytes to be read
* @retlen: Fills the Number of bytes actually read
* @buf: Fills this after reading
*
* Read an address range from the flash chip. The address range
* may be any size provided it is within the physical boundaries.
* Returns 0 on success, non zero otherwise
*/
static int spear_mtd_read(struct mtd_info *mtd, loff_t from, size_t len,
size_t *retlen, u8 *buf)
{
struct spear_snor_flash *flash = get_flash_data(mtd);
struct spear_smi *dev = mtd->priv;
void __iomem *src;
u32 ctrlreg1, val;
int ret;
if (!flash || !dev)
return -ENODEV;
if (flash->bank > dev->num_flashes - 1) {
dev_err(&dev->pdev->dev, "Invalid Bank Num");
return -EINVAL;
}
/* select address as per bank number */
src = flash->base_addr + from;
mutex_lock(&flash->lock);
/* wait till previous write/erase is done. */
ret = spear_smi_wait_till_ready(dev, flash->bank, SMI_MAX_TIME_OUT);
if (ret) {
mutex_unlock(&flash->lock);
return ret;
}
mutex_lock(&dev->lock);
/* put smi in hw mode not wbt mode */
ctrlreg1 = val = readl(dev->io_base + SMI_CR1);
val &= ~(SW_MODE | WB_MODE);
if (flash->fast_mode)
val |= FAST_MODE;
writel(val, dev->io_base + SMI_CR1);
memcpy_fromio(buf, src, len);
/* restore ctrl reg1 */
writel(ctrlreg1, dev->io_base + SMI_CR1);
mutex_unlock(&dev->lock);
*retlen = len;
mutex_unlock(&flash->lock);
return 0;
}
static inline int spear_smi_cpy_toio(struct spear_smi *dev, u32 bank,
void __iomem *dest, const void *src, size_t len)
{
int ret;
u32 ctrlreg1;
/* wait until finished previous write command. */
ret = spear_smi_wait_till_ready(dev, bank, SMI_MAX_TIME_OUT);
if (ret)
return ret;
/* put smi in write enable */
ret = spear_smi_write_enable(dev, bank);
if (ret)
return ret;
/* put smi in hw, write burst mode */
mutex_lock(&dev->lock);
ctrlreg1 = readl(dev->io_base + SMI_CR1);
writel((ctrlreg1 | WB_MODE) & ~SW_MODE, dev->io_base + SMI_CR1);
memcpy_toio(dest, src, len);
writel(ctrlreg1, dev->io_base + SMI_CR1);
mutex_unlock(&dev->lock);
return 0;
}
/**
* spear_mtd_write - performs write operation as requested by the user.
* @mtd: MTD information of the memory bank.
* @to: Address to write.
* @len: Number of bytes to be written.
* @retlen: Number of bytes actually wrote.
* @buf: Buffer from which the data to be taken.
*
* Write an address range to the flash chip. Data must be written in
* flash_page_size chunks. The address range may be any size provided
* it is within the physical boundaries.
* Returns 0 on success, non zero otherwise
*/
static int spear_mtd_write(struct mtd_info *mtd, loff_t to, size_t len,
size_t *retlen, const u8 *buf)
{
struct spear_snor_flash *flash = get_flash_data(mtd);
struct spear_smi *dev = mtd->priv;
void __iomem *dest;
u32 page_offset, page_size;
int ret;
if (!flash || !dev)
return -ENODEV;
if (flash->bank > dev->num_flashes - 1) {
dev_err(&dev->pdev->dev, "Invalid Bank Num");
return -EINVAL;
}
/* select address as per bank number */
dest = flash->base_addr + to;
mutex_lock(&flash->lock);
page_offset = (u32)to % flash->page_size;
/* do if all the bytes fit onto one page */
if (page_offset + len <= flash->page_size) {
ret = spear_smi_cpy_toio(dev, flash->bank, dest, buf, len);
if (!ret)
*retlen += len;
} else {
u32 i;
/* the size of data remaining on the first page */
page_size = flash->page_size - page_offset;
ret = spear_smi_cpy_toio(dev, flash->bank, dest, buf,
page_size);
if (ret)
goto err_write;
else
*retlen += page_size;
/* write everything in pagesize chunks */
for (i = page_size; i < len; i += page_size) {
page_size = len - i;
if (page_size > flash->page_size)
page_size = flash->page_size;
ret = spear_smi_cpy_toio(dev, flash->bank, dest + i,
buf + i, page_size);
if (ret)
break;
else
*retlen += page_size;
}
}
err_write:
mutex_unlock(&flash->lock);
return ret;
}
/**
* spear_smi_probe_flash - Detects the NOR Flash chip.
* @dev: structure of SMI information.
* @bank: bank on which flash must be probed
*
* This routine will check whether there exists a flash chip on a given memory
* bank ID.
* Return index of the probed flash in flash devices structure
*/
static int spear_smi_probe_flash(struct spear_smi *dev, u32 bank)
{
int ret;
u32 val = 0;
ret = spear_smi_wait_till_ready(dev, bank, SMI_PROBE_TIMEOUT);
if (ret)
return ret;
mutex_lock(&dev->lock);
dev->status = 0; /* Will be set in interrupt handler */
/* put smi in sw mode */
val = readl(dev->io_base + SMI_CR1);
writel(val | SW_MODE, dev->io_base + SMI_CR1);
/* send readid command in sw mode */
writel(OPCODE_RDID, dev->io_base + SMI_TR);
val = (bank << BANK_SHIFT) | SEND | (1 << TX_LEN_SHIFT) |
(3 << RX_LEN_SHIFT) | TFIE;
writel(val, dev->io_base + SMI_CR2);
/* wait for TFF */
ret = wait_event_interruptible_timeout(dev->cmd_complete,
dev->status & TFF, SMI_CMD_TIMEOUT);
if (ret <= 0) {
ret = -ENODEV;
goto err_probe;
}
/* get memory chip id */
val = readl(dev->io_base + SMI_RR);
val &= 0x00ffffff;
ret = get_flash_index(val);
err_probe:
/* clear sw mode */
val = readl(dev->io_base + SMI_CR1);
writel(val & ~SW_MODE, dev->io_base + SMI_CR1);
mutex_unlock(&dev->lock);
return ret;
}
#ifdef CONFIG_OF
static int spear_smi_probe_config_dt(struct platform_device *pdev,
struct device_node *np)
{
struct spear_smi_plat_data *pdata = dev_get_platdata(&pdev->dev);
struct device_node *pp = NULL;
const __be32 *addr;
u32 val;
int len;
int i = 0;
if (!np)
return -ENODEV;
of_property_read_u32(np, "clock-rate", &val);
pdata->clk_rate = val;
pdata->board_flash_info = devm_kzalloc(&pdev->dev,
sizeof(*pdata->board_flash_info),
GFP_KERNEL);
/* Fill structs for each subnode (flash device) */
while ((pp = of_get_next_child(np, pp))) {
struct spear_smi_flash_info *flash_info;
flash_info = &pdata->board_flash_info[i];
pdata->np[i] = pp;
/* Read base-addr and size from DT */
addr = of_get_property(pp, "reg", &len);
pdata->board_flash_info->mem_base = be32_to_cpup(&addr[0]);
pdata->board_flash_info->size = be32_to_cpup(&addr[1]);
if (of_get_property(pp, "st,smi-fast-mode", NULL))
pdata->board_flash_info->fast_mode = 1;
i++;
}
pdata->num_flashes = i;
return 0;
}
#else
static int spear_smi_probe_config_dt(struct platform_device *pdev,
struct device_node *np)
{
return -ENOSYS;
}
#endif
static int spear_smi_setup_banks(struct platform_device *pdev,
u32 bank, struct device_node *np)
{
struct spear_smi *dev = platform_get_drvdata(pdev);
struct mtd_part_parser_data ppdata = {};
struct spear_smi_flash_info *flash_info;
struct spear_smi_plat_data *pdata;
struct spear_snor_flash *flash;
struct mtd_partition *parts = NULL;
int count = 0;
int flash_index;
int ret = 0;
pdata = dev_get_platdata(&pdev->dev);
if (bank > pdata->num_flashes - 1)
return -EINVAL;
flash_info = &pdata->board_flash_info[bank];
if (!flash_info)
return -ENODEV;
flash = devm_kzalloc(&pdev->dev, sizeof(*flash), GFP_ATOMIC);
if (!flash)
return -ENOMEM;
flash->bank = bank;
flash->fast_mode = flash_info->fast_mode ? 1 : 0;
mutex_init(&flash->lock);
/* verify whether nor flash is really present on board */
flash_index = spear_smi_probe_flash(dev, bank);
if (flash_index < 0) {
dev_info(&dev->pdev->dev, "smi-nor%d not found\n", bank);
return flash_index;
}
/* map the memory for nor flash chip */
flash->base_addr = devm_ioremap(&pdev->dev, flash_info->mem_base,
flash_info->size);
if (!flash->base_addr)
return -EIO;
dev->flash[bank] = flash;
flash->mtd.priv = dev;
if (flash_info->name)
flash->mtd.name = flash_info->name;
else
flash->mtd.name = flash_devices[flash_index].name;
flash->mtd.type = MTD_NORFLASH;
flash->mtd.writesize = 1;
flash->mtd.flags = MTD_CAP_NORFLASH;
flash->mtd.size = flash_info->size;
flash->mtd.erasesize = flash_devices[flash_index].sectorsize;
flash->page_size = flash_devices[flash_index].pagesize;
flash->mtd.writebufsize = flash->page_size;
flash->erase_cmd = flash_devices[flash_index].erase_cmd;
flash->mtd._erase = spear_mtd_erase;
flash->mtd._read = spear_mtd_read;
flash->mtd._write = spear_mtd_write;
flash->dev_id = flash_devices[flash_index].device_id;
dev_info(&dev->pdev->dev, "mtd .name=%s .size=%llx(%lluM)\n",
flash->mtd.name, flash->mtd.size,
flash->mtd.size / (1024 * 1024));
dev_info(&dev->pdev->dev, ".erasesize = 0x%x(%uK)\n",
flash->mtd.erasesize, flash->mtd.erasesize / 1024);
#ifndef CONFIG_OF
if (flash_info->partitions) {
parts = flash_info->partitions;
count = flash_info->nr_partitions;
}
#endif
ppdata.of_node = np;
ret = mtd_device_parse_register(&flash->mtd, NULL, &ppdata, parts,
count);
if (ret) {
dev_err(&dev->pdev->dev, "Err MTD partition=%d\n", ret);
return ret;
}
return 0;
}
/**
* spear_smi_probe - Entry routine
* @pdev: platform device structure
*
* This is the first routine which gets invoked during booting and does all
* initialization/allocation work. The routine looks for available memory banks,
* and do proper init for any found one.
* Returns 0 on success, non zero otherwise
*/
static int spear_smi_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct spear_smi_plat_data *pdata = NULL;
struct spear_smi *dev;
struct resource *smi_base;
int irq, ret = 0;
int i;
if (np) {
pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
if (!pdata) {
ret = -ENOMEM;
goto err;
}
pdev->dev.platform_data = pdata;
ret = spear_smi_probe_config_dt(pdev, np);
if (ret) {
ret = -ENODEV;
dev_err(&pdev->dev, "no platform data\n");
goto err;
}
} else {
pdata = dev_get_platdata(&pdev->dev);
if (!pdata) {
ret = -ENODEV;
dev_err(&pdev->dev, "no platform data\n");
goto err;
}
}
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
ret = -ENODEV;
dev_err(&pdev->dev, "invalid smi irq\n");
goto err;
}
dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_ATOMIC);
if (!dev) {
ret = -ENOMEM;
goto err;
}
smi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0);
dev->io_base = devm_ioremap_resource(&pdev->dev, smi_base);
if (IS_ERR(dev->io_base)) {
ret = PTR_ERR(dev->io_base);
goto err;
}
dev->pdev = pdev;
dev->clk_rate = pdata->clk_rate;
if (dev->clk_rate > SMI_MAX_CLOCK_FREQ)
dev->clk_rate = SMI_MAX_CLOCK_FREQ;
dev->num_flashes = pdata->num_flashes;
if (dev->num_flashes > MAX_NUM_FLASH_CHIP) {
dev_err(&pdev->dev, "exceeding max number of flashes\n");
dev->num_flashes = MAX_NUM_FLASH_CHIP;
}
dev->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(dev->clk)) {
ret = PTR_ERR(dev->clk);
goto err;
}
ret = clk_prepare_enable(dev->clk);
if (ret)
goto err;
ret = devm_request_irq(&pdev->dev, irq, spear_smi_int_handler, 0,
pdev->name, dev);
if (ret) {
dev_err(&dev->pdev->dev, "SMI IRQ allocation failed\n");
goto err_irq;
}
mutex_init(&dev->lock);
init_waitqueue_head(&dev->cmd_complete);
spear_smi_hw_init(dev);
platform_set_drvdata(pdev, dev);
/* loop for each serial nor-flash which is connected to smi */
for (i = 0; i < dev->num_flashes; i++) {
ret = spear_smi_setup_banks(pdev, i, pdata->np[i]);
if (ret) {
dev_err(&dev->pdev->dev, "bank setup failed\n");
goto err_irq;
}
}
return 0;
err_irq:
clk_disable_unprepare(dev->clk);
err:
return ret;
}
/**
* spear_smi_remove - Exit routine
* @pdev: platform device structure
*
* free all allocations and delete the partitions.
*/
static int spear_smi_remove(struct platform_device *pdev)
{
struct spear_smi *dev;
struct spear_snor_flash *flash;
int ret, i;
dev = platform_get_drvdata(pdev);
if (!dev) {
dev_err(&pdev->dev, "dev is null\n");
return -ENODEV;
}
/* clean up for all nor flash */
for (i = 0; i < dev->num_flashes; i++) {
flash = dev->flash[i];
if (!flash)
continue;
/* clean up mtd stuff */
ret = mtd_device_unregister(&flash->mtd);
if (ret)
dev_err(&pdev->dev, "error removing mtd\n");
}
clk_disable_unprepare(dev->clk);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int spear_smi_suspend(struct device *dev)
{
struct spear_smi *sdev = dev_get_drvdata(dev);
if (sdev && sdev->clk)
clk_disable_unprepare(sdev->clk);
return 0;
}
static int spear_smi_resume(struct device *dev)
{
struct spear_smi *sdev = dev_get_drvdata(dev);
int ret = -EPERM;
if (sdev && sdev->clk)
ret = clk_prepare_enable(sdev->clk);
if (!ret)
spear_smi_hw_init(sdev);
return ret;
}
#endif
static SIMPLE_DEV_PM_OPS(spear_smi_pm_ops, spear_smi_suspend, spear_smi_resume);
#ifdef CONFIG_OF
static const struct of_device_id spear_smi_id_table[] = {
{ .compatible = "st,spear600-smi" },
{}
};
MODULE_DEVICE_TABLE(of, spear_smi_id_table);
#endif
static struct platform_driver spear_smi_driver = {
.driver = {
.name = "smi",
.bus = &platform_bus_type,
.of_match_table = of_match_ptr(spear_smi_id_table),
.pm = &spear_smi_pm_ops,
},
.probe = spear_smi_probe,
.remove = spear_smi_remove,
};
module_platform_driver(spear_smi_driver);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Ashish Priyadarshi, Shiraz Hashim <shiraz.linux.kernel@gmail.com>");
MODULE_DESCRIPTION("MTD SMI driver for serial nor flash chips");