diff options
Diffstat (limited to 'kernel/drivers/mtd/devices/spear_smi.c')
| -rw-r--r-- | kernel/drivers/mtd/devices/spear_smi.c | 1092 |
1 files changed, 1092 insertions, 0 deletions
diff --git a/kernel/drivers/mtd/devices/spear_smi.c b/kernel/drivers/mtd/devices/spear_smi.c new file mode 100644 index 000000000..508bab3bd --- /dev/null +++ b/kernel/drivers/mtd/devices/spear_smi.c @@ -0,0 +1,1092 @@ +/* + * 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SPEAr platform + * The serial nor interface is largely based on drivers/mtd/m25p80.c, + * however the SPI interface has been replaced by SMI.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"); |