[PATCH RFC 3/3] nand: pl353: Add driver for arm pl353 smc nand interface

punnaiah choudary kalluri punnaia at xilinx.com
Thu Apr 3 07:58:55 PDT 2014


On Thu, Apr 3, 2014 at 8:04 PM, Ezequiel García
<ezequiel at vanguardiasur.com.ar> wrote:
> On 27 March 2014 15:21, Punnaiah Choudary Kalluri
> <punnaiah.choudary.kalluri at xilinx.com> wrote:
>> Add driver for arm pl353 static memory controller nand interface.
>> This controller is used in xilinx zynq soc for interfacing the nand
>> flash memory.
>>
>> Signed-off-by: Punnaiah Choudary Kalluri <punnaia at xilinx.com>
>> ---
>>  drivers/mtd/nand/Kconfig      |    8 +
>>  drivers/mtd/nand/Makefile     |    1 +
>>  drivers/mtd/nand/pl353_nand.c | 1122 +++++++++++++++++++++++++++++++++++++++++
>>  3 files changed, 1131 insertions(+), 0 deletions(-)
>>  create mode 100644 drivers/mtd/nand/pl353_nand.c
>>
>> diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig
>> index 90ff447..31c1d0c 100644
>> --- a/drivers/mtd/nand/Kconfig
>> +++ b/drivers/mtd/nand/Kconfig
>> @@ -510,4 +510,12 @@ config MTD_NAND_XWAY
>>           Enables support for NAND Flash chips on Lantiq XWAY SoCs. NAND is attached
>>           to the External Bus Unit (EBU).
>>
>> +config MTD_NAND_PL353
>> +       tristate "ARM Pl353 NAND flash driver"
>> +       depends on MTD_NAND && ARM
>> +       select PL353_SMC
>> +       help
>> +         This enables access to the NAND flash device on PL353 SMC
>> +         controller.
>> +
>>  endif # MTD_NAND
>> diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile
>> index 542b568..a4c2679 100644
>> --- a/drivers/mtd/nand/Makefile
>> +++ b/drivers/mtd/nand/Makefile
>> @@ -49,5 +49,6 @@ obj-$(CONFIG_MTD_NAND_JZ4740)         += jz4740_nand.o
>>  obj-$(CONFIG_MTD_NAND_GPMI_NAND)       += gpmi-nand/
>>  obj-$(CONFIG_MTD_NAND_XWAY)            += xway_nand.o
>>  obj-$(CONFIG_MTD_NAND_BCM47XXNFLASH)   += bcm47xxnflash/
>> +obj-$(CONFIG_MTD_NAND_PL353)           += pl353_nand.o
>>
>>  nand-objs := nand_base.o nand_bbt.o
>> diff --git a/drivers/mtd/nand/pl353_nand.c b/drivers/mtd/nand/pl353_nand.c
>> new file mode 100644
>> index 0000000..ee74545
>> --- /dev/null
>> +++ b/drivers/mtd/nand/pl353_nand.c
>> @@ -0,0 +1,1122 @@
>> +/*
>> + * ARM PL353 NAND Flash Controller Driver
>> + *
>> + * Copyright (C) 2009 - 2014 Xilinx, Inc.
>> + *
>> + * This driver is based on plat_nand.c and mxc_nand.c drivers
>> + *
>> + * 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; either version 2 of the License, or (at your
>> + * option) any later version.
>> + */
>> +
>> +#include <linux/err.h>
>> +#include <linux/delay.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/io.h>
>> +#include <linux/ioport.h>
>> +#include <linux/irq.h>
>> +#include <linux/memory/pl353-smc.h>
>> +#include <linux/module.h>
>> +#include <linux/moduleparam.h>
>> +#include <linux/mtd/mtd.h>
>> +#include <linux/mtd/nand.h>
>> +#include <linux/mtd/nand_ecc.h>
>> +#include <linux/mtd/partitions.h>
>> +#include <linux/of_address.h>
>> +#include <linux/of_device.h>
>> +#include <linux/of_platform.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/slab.h>
>> +
>> +#define PL353_NAND_DRIVER_NAME "pl353-nand"
>> +
>> +/* NAND flash driver defines */
>> +#define PL353_NAND_CMD_PHASE   1       /* End command valid in command phase */
>> +#define PL353_NAND_DATA_PHASE  2       /* End command valid in data phase */
>> +#define PL353_NAND_ECC_SIZE    512     /* Size of data for ECC operation */
>> +
>> +/* Flash memory controller operating parameters */
>> +
>> +#define PL353_NAND_ECC_CONFIG  (BIT(4)  |      /* ECC read at end of page */ \
>> +                                (0 << 5))      /* No Jumping */
>> +
>> +/* AXI Address definitions */
>> +#define START_CMD_SHIFT                3
>> +#define END_CMD_SHIFT          11
>> +#define END_CMD_VALID_SHIFT    20
>> +#define ADDR_CYCLES_SHIFT      21
>> +#define CLEAR_CS_SHIFT         21
>> +#define ECC_LAST_SHIFT         10
>> +#define COMMAND_PHASE          (0 << 19)
>> +#define DATA_PHASE             BIT(19)
>> +
>> +#define PL353_NAND_ECC_LAST    BIT(ECC_LAST_SHIFT)     /* Set ECC_Last */
>> +#define PL353_NAND_CLEAR_CS    BIT(CLEAR_CS_SHIFT)     /* Clear chip select */
>> +
>> +#define ONDIE_ECC_FEATURE_ADDR 0x90
>> +#define PL353_NAND_ECC_BUSY_TIMEOUT    (1 * HZ)
>> +#define PL353_NAND_DEV_BUSY_TIMEOUT    (1 * HZ)
>> +#define PL353_NAND_LAST_TRANSFER_LENGTH        4
>> +
>> +/* Inline function for the NAND controller register write */
>> +static inline void pl353_nand_write32(void __iomem *addr, u32 val)
>> +{
>> +       writel_relaxed((val), (addr));
>> +}
>> +
>
> Hm... you can just use writel_relaxed instead of this dummy helper.

Ok. its been used in two places. Still I will fix this.

>
>> +/**
>> + * struct pl353_nand_command_format - Defines NAND flash command format
>> + * @start_cmd:         First cycle command (Start command)
>> + * @end_cmd:           Second cycle command (Last command)
>> + * @addr_cycles:       Number of address cycles required to send the address
>> + * @end_cmd_valid:     The second cycle command is valid for cmd or data phase
>> + */
>> +struct pl353_nand_command_format {
>> +       int start_cmd;
>> +       int end_cmd;
>> +       u8 addr_cycles;
>> +       u8 end_cmd_valid;
>> +};
>> +
>> +/**
>> + * struct pl353_nand_info - Defines the NAND flash driver instance
>> + * @chip:              NAND chip information structure
>> + * @mtd:               MTD information structure
>> + * @parts:             Pointer to the mtd_partition structure
>> + * @nand_base:         Virtual address of the NAND flash device
>> + * @end_cmd_pending:   End command is pending
>> + * @end_cmd:           End command
>> + */
>> +struct pl353_nand_info {
>> +       struct nand_chip chip;
>> +       struct mtd_info mtd;
>> +       struct mtd_partition *parts;
>
> I can't see this "parts" field being used anywhere. What am I missing?

oh!  yes, it is unused. I will remove this field and also the
unnecessary reference in
pl353_nand_remove function

Thanks,
Punnaiah
>
>> +       void __iomem *nand_base;
>> +       unsigned long end_cmd_pending;
>> +       unsigned long end_cmd;
>> +};
>> +
>> +/*
>> + * The NAND flash operations command format
>> + */
>> +static const struct pl353_nand_command_format pl353_nand_commands[] = {
>> +       {NAND_CMD_READ0, NAND_CMD_READSTART, 5, PL353_NAND_CMD_PHASE},
>> +       {NAND_CMD_RNDOUT, NAND_CMD_RNDOUTSTART, 2, PL353_NAND_CMD_PHASE},
>> +       {NAND_CMD_READID, NAND_CMD_NONE, 1, NAND_CMD_NONE},
>> +       {NAND_CMD_STATUS, NAND_CMD_NONE, 0, NAND_CMD_NONE},
>> +       {NAND_CMD_SEQIN, NAND_CMD_PAGEPROG, 5, PL353_NAND_DATA_PHASE},
>> +       {NAND_CMD_RNDIN, NAND_CMD_NONE, 2, NAND_CMD_NONE},
>> +       {NAND_CMD_ERASE1, NAND_CMD_ERASE2, 3, PL353_NAND_CMD_PHASE},
>> +       {NAND_CMD_RESET, NAND_CMD_NONE, 0, NAND_CMD_NONE},
>> +       {NAND_CMD_PARAM, NAND_CMD_NONE, 1, NAND_CMD_NONE},
>> +       {NAND_CMD_GET_FEATURES, NAND_CMD_NONE, 1, NAND_CMD_NONE},
>> +       {NAND_CMD_SET_FEATURES, NAND_CMD_NONE, 1, NAND_CMD_NONE},
>> +       {NAND_CMD_NONE, NAND_CMD_NONE, 0, 0},
>> +       /* Add all the flash commands supported by the flash device and Linux */
>> +       /*
>> +        * The cache program command is not supported by driver because driver
>> +        * cant differentiate between page program and cached page program from
>> +        * start command, these commands can be differentiated through end
>> +        * command, which doesn't fit in to the driver design. The cache program
>> +        * command is not supported by NAND subsystem also, look at 1612 line
>> +        * number (in nand_write_page function) of nand_base.c file.
>> +        * {NAND_CMD_SEQIN, NAND_CMD_CACHEDPROG, 5, PL353_NAND_YES},
>> +        */
>> +};
>> +
>> +/* Define default oob placement schemes for large and small page devices */
>> +static struct nand_ecclayout nand_oob_16 = {
>> +       .eccbytes = 3,
>> +       .eccpos = {0, 1, 2},
>> +       .oobfree = {
>> +               {.offset = 8,
>> +                . length = 8} }
>> +};
>> +
>> +static struct nand_ecclayout nand_oob_64 = {
>> +       .eccbytes = 12,
>> +       .eccpos = {
>> +                  52, 53, 54, 55, 56, 57,
>> +                  58, 59, 60, 61, 62, 63},
>> +       .oobfree = {
>> +               {.offset = 2,
>> +                .length = 50} }
>> +};
>> +
>> +static struct nand_ecclayout ondie_nand_oob_64 = {
>> +       .eccbytes = 32,
>> +
>> +       .eccpos = {
>> +               8, 9, 10, 11, 12, 13, 14, 15,
>> +               24, 25, 26, 27, 28, 29, 30, 31,
>> +               40, 41, 42, 43, 44, 45, 46, 47,
>> +               56, 57, 58, 59, 60, 61, 62, 63
>> +       },
>> +
>> +       .oobfree = {
>> +               { .offset = 4, .length = 4 },
>> +               { .offset = 20, .length = 4 },
>> +               { .offset = 36, .length = 4 },
>> +               { .offset = 52, .length = 4 }
>> +       }
>> +};
>> +
>> +/* Generic flash bbt decriptors */
>> +static uint8_t bbt_pattern[] = { 'B', 'b', 't', '0' };
>> +static uint8_t mirror_pattern[] = { '1', 't', 'b', 'B' };
>> +
>> +static struct nand_bbt_descr bbt_main_descr = {
>> +       .options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
>> +               | NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
>> +       .offs = 4,
>> +       .len = 4,
>> +       .veroffs = 20,
>> +       .maxblocks = 4,
>> +       .pattern = bbt_pattern
>> +};
>> +
>> +static struct nand_bbt_descr bbt_mirror_descr = {
>> +       .options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
>> +               | NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
>> +       .offs = 4,
>> +       .len = 4,
>> +       .veroffs = 20,
>> +       .maxblocks = 4,
>> +       .pattern = mirror_pattern
>> +};
>> +
>> +/**
>> + * pl353_nand_calculate_hwecc - Calculate Hardware ECC
>> + * @mtd:       Pointer to the mtd_info structure
>> + * @data:      Pointer to the page data
>> + * @ecc_code:  Pointer to the ECC buffer where ECC data needs to be stored
>> + *
>> + * This function retrieves the Hardware ECC data from the controller and returns
>> + * ECC data back to the MTD subsystem.
>> + *
>> + * Return:     0 on success or error value on failure
>> + */
>> +static int pl353_nand_calculate_hwecc(struct mtd_info *mtd,
>> +                               const u8 *data, u8 *ecc_code)
>> +{
>> +       u32 ecc_value, ecc_status;
>> +       u8 ecc_reg, ecc_byte;
>> +       unsigned long timeout = jiffies + PL353_NAND_ECC_BUSY_TIMEOUT;
>> +
>> +       /* Wait till the ECC operation is complete or timeout */
>> +       do {
>> +               if (pl353_smc_ecc_is_busy())
>> +                       cpu_relax();
>> +               else
>> +                       break;
>> +       } while (!time_after_eq(jiffies, timeout));
>> +
>> +       if (time_after_eq(jiffies, timeout)) {
>> +               pr_err("%s timed out\n", __func__);
>> +               return -ETIMEDOUT;
>> +       }
>> +
>> +       for (ecc_reg = 0; ecc_reg < 4; ecc_reg++) {
>> +               /* Read ECC value for each block */
>> +               ecc_value = pl353_smc_get_ecc_val(ecc_reg);
>> +               ecc_status = (ecc_value >> 24) & 0xFF;
>> +               /* ECC value valid */
>> +               if (ecc_status & 0x40) {
>> +                       for (ecc_byte = 0; ecc_byte < 3; ecc_byte++) {
>> +                               /* Copy ECC bytes to MTD buffer */
>> +                               *ecc_code = ecc_value & 0xFF;
>> +                               ecc_value = ecc_value >> 8;
>> +                               ecc_code++;
>> +                       }
>> +               } else {
>> +                       pr_warn("%s status failed\n", __func__);
>> +                       return -1;
>> +               }
>> +       }
>> +       return 0;
>> +}
>> +
>> +/**
>> + * onehot - onehot function
>> + * @value:     Value to check for onehot
>> + *
>> + * This function checks whether a value is onehot or not.
>> + * onehot is if and only if onebit is set.
>> + *
>> + * Return:     1 if it is onehot else 0
>> + */
>> +static int onehot(unsigned short value)
>> +{
>> +       return (value & (value - 1)) == 0;
>> +}
>> +
>> +/**
>> + * pl353_nand_correct_data - ECC correction function
>> + * @mtd:       Pointer to the mtd_info structure
>> + * @buf:       Pointer to the page data
>> + * @read_ecc:  Pointer to the ECC value read from spare data area
>> + * @calc_ecc:  Pointer to the calculated ECC value
>> + *
>> + * This function corrects the ECC single bit errors & detects 2-bit errors.
>> + *
>> + * Return:     0 if no ECC errors found
>> + *             1 if single bit error found and corrected.
>> + *             -1 if multiple ECC errors found.
>> + */
>> +static int pl353_nand_correct_data(struct mtd_info *mtd, unsigned char *buf,
>> +                               unsigned char *read_ecc,
>> +                               unsigned char *calc_ecc)
>> +{
>> +       unsigned char bit_addr;
>> +       unsigned int byte_addr;
>> +       unsigned short ecc_odd, ecc_even, read_ecc_lower, read_ecc_upper;
>> +       unsigned short calc_ecc_lower, calc_ecc_upper;
>> +
>> +       read_ecc_lower = (read_ecc[0] | (read_ecc[1] << 8)) & 0xfff;
>> +       read_ecc_upper = ((read_ecc[1] >> 4) | (read_ecc[2] << 4)) & 0xfff;
>> +
>> +       calc_ecc_lower = (calc_ecc[0] | (calc_ecc[1] << 8)) & 0xfff;
>> +       calc_ecc_upper = ((calc_ecc[1] >> 4) | (calc_ecc[2] << 4)) & 0xfff;
>> +
>> +       ecc_odd = read_ecc_lower ^ calc_ecc_lower;
>> +       ecc_even = read_ecc_upper ^ calc_ecc_upper;
>> +
>> +       if ((ecc_odd == 0) && (ecc_even == 0))
>> +               return 0;       /* no error */
>> +
>> +       if (ecc_odd == (~ecc_even & 0xfff)) {
>> +               /* bits [11:3] of error code is byte offset */
>> +               byte_addr = (ecc_odd >> 3) & 0x1ff;
>> +               /* bits [2:0] of error code is bit offset */
>> +               bit_addr = ecc_odd & 0x7;
>> +               /* Toggling error bit */
>> +               buf[byte_addr] ^= (1 << bit_addr);
>> +               return 1;
>> +       }
>> +
>> +       if (onehot(ecc_odd | ecc_even) == 1)
>> +               return 1; /* one error in parity */
>> +
>> +       return -1; /* Uncorrectable error */
>> +}
>> +
>> +/**
>> + * pl353_nand_read_oob - [REPLACABLE] the most common OOB data read function
>> + * @mtd:       Pointer to the mtd info structure
>> + * @chip:      Pointer to the NAND chip info structure
>> + * @page:      Page number to read
>> + *
>> + * Return:     Always return zero
>> + */
>> +static int pl353_nand_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
>> +                           int page)
>> +{
>> +       unsigned long data_phase_addr;
>> +       uint8_t *p;
>> +
>> +       chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
>> +
>> +       p = chip->oob_poi;
>> +       chip->read_buf(mtd, p,
>> +                       (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH));
>> +       p += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
>> +
>> +       data_phase_addr = (unsigned long __force)chip->IO_ADDR_R;
>> +       data_phase_addr |= PL353_NAND_CLEAR_CS;
>> +       chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
>> +       chip->read_buf(mtd, p, PL353_NAND_LAST_TRANSFER_LENGTH);
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * pl353_nand_write_oob - [REPLACABLE] the most common OOB data write function
>> + * @mtd:       Pointer to the mtd info structure
>> + * @chip:      Pointer to the NAND chip info structure
>> + * @page:      Page number to write
>> + *
>> + * Return:     Zero on success and EIO on failure
>> + */
>> +static int pl353_nand_write_oob(struct mtd_info *mtd, struct nand_chip *chip,
>> +                            int page)
>> +{
>> +       int status = 0;
>> +       const uint8_t *buf = chip->oob_poi;
>> +       unsigned long data_phase_addr;
>> +
>> +       chip->cmdfunc(mtd, NAND_CMD_SEQIN, mtd->writesize, page);
>> +
>> +       chip->write_buf(mtd, buf,
>> +                       (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH));
>> +       buf += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
>> +
>> +       data_phase_addr = (unsigned long __force)chip->IO_ADDR_W;
>> +       data_phase_addr |= PL353_NAND_CLEAR_CS;
>> +       data_phase_addr |= (1 << END_CMD_VALID_SHIFT);
>> +       chip->IO_ADDR_W = (void __iomem * __force)data_phase_addr;
>> +       chip->write_buf(mtd, buf, PL353_NAND_LAST_TRANSFER_LENGTH);
>> +
>> +       /* Send command to program the OOB data */
>> +       chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
>> +       status = chip->waitfunc(mtd, chip);
>> +
>> +       return status & NAND_STATUS_FAIL ? -EIO : 0;
>> +}
>> +
>> +/**
>> + * pl353_nand_read_page_raw - [Intern] read raw page data without ecc
>> + * @mtd:               Pointer to the mtd info structure
>> + * @chip:              Pointer to the NAND chip info structure
>> + * @buf:               Pointer to the data buffer
>> + * @oob_required:      Caller requires OOB data read to chip->oob_poi
>> + * @page:              Page number to read
>> + *
>> + * Return:     Always return zero
>> + */
>> +static int pl353_nand_read_page_raw(struct mtd_info *mtd,
>> +                               struct nand_chip *chip,
>> +                               uint8_t *buf, int oob_required, int page)
>> +{
>> +       unsigned long data_phase_addr;
>> +       uint8_t *p;
>> +
>> +       chip->read_buf(mtd, buf, mtd->writesize);
>> +
>> +       p = chip->oob_poi;
>> +       chip->read_buf(mtd, p,
>> +                       (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH));
>> +       p += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
>> +
>> +       data_phase_addr = (unsigned long __force)chip->IO_ADDR_R;
>> +       data_phase_addr |= PL353_NAND_CLEAR_CS;
>> +       chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
>> +
>> +       chip->read_buf(mtd, p, PL353_NAND_LAST_TRANSFER_LENGTH);
>> +       return 0;
>> +}
>> +
>> +/**
>> + * pl353_nand_write_page_raw - [Intern] raw page write function
>> + * @mtd:               Pointer to the mtd info structure
>> + * @chip:              Pointer to the NAND chip info structure
>> + * @buf:               Pointer to the data buffer
>> + * @oob_required:      Caller requires OOB data read to chip->oob_poi
>> + *
>> + * Return:     Always return zero
>> + */
>> +static int pl353_nand_write_page_raw(struct mtd_info *mtd,
>> +                                   struct nand_chip *chip,
>> +                                   const uint8_t *buf, int oob_required)
>> +{
>> +       unsigned long data_phase_addr;
>> +       uint8_t *p;
>> +
>> +       chip->write_buf(mtd, buf, mtd->writesize);
>> +
>> +       p = chip->oob_poi;
>> +       chip->write_buf(mtd, p,
>> +                       (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH));
>> +       p += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
>> +
>> +       data_phase_addr = (unsigned long __force)chip->IO_ADDR_W;
>> +       data_phase_addr |= PL353_NAND_CLEAR_CS;
>> +       data_phase_addr |= (1 << END_CMD_VALID_SHIFT);
>> +       chip->IO_ADDR_W = (void __iomem * __force)data_phase_addr;
>> +
>> +       chip->write_buf(mtd, p, PL353_NAND_LAST_TRANSFER_LENGTH);
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * nand_write_page_hwecc - Hardware ECC based page write function
>> + * @mtd:               Pointer to the mtd info structure
>> + * @chip:              Pointer to the NAND chip info structure
>> + * @buf:               Pointer to the data buffer
>> + * @oob_required:      Caller requires OOB data read to chip->oob_poi
>> + *
>> + * This functions writes data and hardware generated ECC values in to the page.
>> + *
>> + * Return:     Always return zero
>> + */
>> +static int pl353_nand_write_page_hwecc(struct mtd_info *mtd,
>> +                                   struct nand_chip *chip, const uint8_t *buf,
>> +                                   int oob_required)
>> +{
>> +       int i, eccsize = chip->ecc.size;
>> +       int eccsteps = chip->ecc.steps;
>> +       uint8_t *ecc_calc = chip->buffers->ecccalc;
>> +       const uint8_t *p = buf;
>> +       uint32_t *eccpos = chip->ecc.layout->eccpos;
>> +       unsigned long data_phase_addr;
>> +       uint8_t *oob_ptr;
>> +
>> +       for ( ; (eccsteps - 1); eccsteps--) {
>> +               chip->write_buf(mtd, p, eccsize);
>> +               p += eccsize;
>> +       }
>> +       chip->write_buf(mtd, p, (eccsize - PL353_NAND_LAST_TRANSFER_LENGTH));
>> +       p += (eccsize - PL353_NAND_LAST_TRANSFER_LENGTH);
>> +
>> +       /* Set ECC Last bit to 1 */
>> +       data_phase_addr = (unsigned long __force)chip->IO_ADDR_W;
>> +       data_phase_addr |= PL353_NAND_ECC_LAST;
>> +       chip->IO_ADDR_W = (void __iomem * __force)data_phase_addr;
>> +       chip->write_buf(mtd, p, PL353_NAND_LAST_TRANSFER_LENGTH);
>> +
>> +       /* Wait for ECC to be calculated and read the error values */
>> +       p = buf;
>> +       chip->ecc.calculate(mtd, p, &ecc_calc[0]);
>> +
>> +       for (i = 0; i < chip->ecc.total; i++)
>> +               chip->oob_poi[eccpos[i]] = ~(ecc_calc[i]);
>> +
>> +       /* Clear ECC last bit */
>> +       data_phase_addr = (unsigned long __force)chip->IO_ADDR_W;
>> +       data_phase_addr &= ~PL353_NAND_ECC_LAST;
>> +       chip->IO_ADDR_W = (void __iomem * __force)data_phase_addr;
>> +
>> +       /* Write the spare area with ECC bytes */
>> +       oob_ptr = chip->oob_poi;
>> +       chip->write_buf(mtd, oob_ptr,
>> +                       (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH));
>> +
>> +       data_phase_addr = (unsigned long __force)chip->IO_ADDR_W;
>> +       data_phase_addr |= PL353_NAND_CLEAR_CS;
>> +       data_phase_addr |= (1 << END_CMD_VALID_SHIFT);
>> +       chip->IO_ADDR_W = (void __iomem * __force)data_phase_addr;
>> +       oob_ptr += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
>> +       chip->write_buf(mtd, oob_ptr, PL353_NAND_LAST_TRANSFER_LENGTH);
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * pl353_nand_write_page_swecc - [REPLACABLE] software ecc based page write function
>> + * @mtd:               Pointer to the mtd info structure
>> + * @chip:              Pointer to the NAND chip info structure
>> + * @buf:               Pointer to the data buffer
>> + * @oob_required:      Caller requires OOB data read to chip->oob_poi
>> + *
>> + * Return:     Always return zero
>> + */
>> +static int pl353_nand_write_page_swecc(struct mtd_info *mtd,
>> +                                   struct nand_chip *chip, const uint8_t *buf,
>> +                                   int oob_required)
>> +{
>> +       int i, eccsize = chip->ecc.size;
>> +       int eccbytes = chip->ecc.bytes;
>> +       int eccsteps = chip->ecc.steps;
>> +       uint8_t *ecc_calc = chip->buffers->ecccalc;
>> +       const uint8_t *p = buf;
>> +       uint32_t *eccpos = chip->ecc.layout->eccpos;
>> +
>> +       /* Software ecc calculation */
>> +       for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize)
>> +               chip->ecc.calculate(mtd, p, &ecc_calc[i]);
>> +
>> +       for (i = 0; i < chip->ecc.total; i++)
>> +               chip->oob_poi[eccpos[i]] = ecc_calc[i];
>> +
>> +       chip->ecc.write_page_raw(mtd, chip, buf, 1);
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * pl353_nand_read_page_hwecc - Hardware ECC based page read function
>> + * @mtd:               Pointer to the mtd info structure
>> + * @chip:              Pointer to the NAND chip info structure
>> + * @buf:               Pointer to the buffer to store read data
>> + * @oob_required:      Caller requires OOB data read to chip->oob_poi
>> + * @page:              Page number to read
>> + *
>> + * This functions reads data and checks the data integrity by comparing hardware
>> + * generated ECC values and read ECC values from spare area.
>> + *
>> + * Return:     0 always and updates ECC operation status in to MTD structure
>> + */
>> +static int pl353_nand_read_page_hwecc(struct mtd_info *mtd,
>> +                                    struct nand_chip *chip,
>> +                                    uint8_t *buf, int oob_required, int page)
>> +{
>> +       int i, stat, eccsize = chip->ecc.size;
>> +       int eccbytes = chip->ecc.bytes;
>> +       int eccsteps = chip->ecc.steps;
>> +       uint8_t *p = buf;
>> +       uint8_t *ecc_calc = chip->buffers->ecccalc;
>> +       uint8_t *ecc_code = chip->buffers->ecccode;
>> +       uint32_t *eccpos = chip->ecc.layout->eccpos;
>> +       unsigned long data_phase_addr;
>> +       uint8_t *oob_ptr;
>> +
>> +       for ( ; (eccsteps - 1); eccsteps--) {
>> +               chip->read_buf(mtd, p, eccsize);
>> +               p += eccsize;
>> +       }
>> +       chip->read_buf(mtd, p, (eccsize - PL353_NAND_LAST_TRANSFER_LENGTH));
>> +       p += (eccsize - PL353_NAND_LAST_TRANSFER_LENGTH);
>> +
>> +       /* Set ECC Last bit to 1 */
>> +       data_phase_addr = (unsigned long __force)chip->IO_ADDR_R;
>> +       data_phase_addr |= PL353_NAND_ECC_LAST;
>> +       chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
>> +       chip->read_buf(mtd, p, PL353_NAND_LAST_TRANSFER_LENGTH);
>> +
>> +       /* Read the calculated ECC value */
>> +       p = buf;
>> +       chip->ecc.calculate(mtd, p, &ecc_calc[0]);
>> +
>> +       /* Clear ECC last bit */
>> +       data_phase_addr = (unsigned long __force)chip->IO_ADDR_R;
>> +       data_phase_addr &= ~PL353_NAND_ECC_LAST;
>> +       chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
>> +
>> +       /* Read the stored ECC value */
>> +       oob_ptr = chip->oob_poi;
>> +       chip->read_buf(mtd, oob_ptr,
>> +                       (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH));
>> +
>> +       /* de-assert chip select */
>> +       data_phase_addr = (unsigned long __force)chip->IO_ADDR_R;
>> +       data_phase_addr |= PL353_NAND_CLEAR_CS;
>> +       chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
>> +
>> +       oob_ptr += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
>> +       chip->read_buf(mtd, oob_ptr, PL353_NAND_LAST_TRANSFER_LENGTH);
>> +
>> +       for (i = 0; i < chip->ecc.total; i++)
>> +               ecc_code[i] = ~(chip->oob_poi[eccpos[i]]);
>> +
>> +       eccsteps = chip->ecc.steps;
>> +       p = buf;
>> +
>> +       /* Check ECC error for all blocks and correct if it is correctable */
>> +       for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
>> +               stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
>> +               if (stat < 0)
>> +                       mtd->ecc_stats.failed++;
>> +               else
>> +                       mtd->ecc_stats.corrected += stat;
>> +       }
>> +       return 0;
>> +}
>> +
>> +/**
>> + * pl353_nand_read_page_swecc - [REPLACABLE] software ecc based page read function
>> + * @mtd:               Pointer to the mtd info structure
>> + * @chip:              Pointer to the NAND chip info structure
>> + * @buf:               Pointer to the buffer to store read data
>> + * @oob_required:      Caller requires OOB data read to chip->oob_poi
>> + * @page:              Page number to read
>> + *
>> + * Return:     Always return zero
>> + */
>> +static int pl353_nand_read_page_swecc(struct mtd_info *mtd,
>> +                                    struct nand_chip *chip,
>> +                                    uint8_t *buf,  int oob_required, int page)
>> +{
>> +       int i, eccsize = chip->ecc.size;
>> +       int eccbytes = chip->ecc.bytes;
>> +       int eccsteps = chip->ecc.steps;
>> +       uint8_t *p = buf;
>> +       uint8_t *ecc_calc = chip->buffers->ecccalc;
>> +       uint8_t *ecc_code = chip->buffers->ecccode;
>> +       uint32_t *eccpos = chip->ecc.layout->eccpos;
>> +
>> +       chip->ecc.read_page_raw(mtd, chip, buf, page, 1);
>> +
>> +       for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize)
>> +               chip->ecc.calculate(mtd, p, &ecc_calc[i]);
>> +
>> +       for (i = 0; i < chip->ecc.total; i++)
>> +               ecc_code[i] = chip->oob_poi[eccpos[i]];
>> +
>> +       eccsteps = chip->ecc.steps;
>> +       p = buf;
>> +
>> +       for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
>> +               int stat;
>> +
>> +               stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
>> +               if (stat < 0)
>> +                       mtd->ecc_stats.failed++;
>> +               else
>> +                       mtd->ecc_stats.corrected += stat;
>> +       }
>> +       return 0;
>> +}
>> +
>> +/**
>> + * pl353_nand_select_chip - Select the flash device
>> + * @mtd:       Pointer to the mtd info structure
>> + * @chip:      Pointer to the NAND chip info structure
>> + *
>> + * This function is empty as the NAND controller handles chip select line
>> + * internally based on the chip address passed in command and data phase.
>> + */
>> +static void pl353_nand_select_chip(struct mtd_info *mtd, int chip)
>> +{
>> +       return;
>> +}
>> +
>> +/**
>> + * pl353_nand_cmd_function - Send command to NAND device
>> + * @mtd:       Pointer to the mtd_info structure
>> + * @command:   The command to be sent to the flash device
>> + * @column:    The column address for this command, -1 if none
>> + * @page_addr: The page address for this command, -1 if none
>> + */
>> +static void pl353_nand_cmd_function(struct mtd_info *mtd, unsigned int command,
>> +                                int column, int page_addr)
>> +{
>> +       struct nand_chip *chip = mtd->priv;
>> +       const struct pl353_nand_command_format *curr_cmd = NULL;
>> +       struct pl353_nand_info *xnand =
>> +               container_of(mtd, struct pl353_nand_info, mtd);
>> +       void __iomem *cmd_addr;
>> +       unsigned long cmd_data = 0, end_cmd_valid = 0;
>> +       unsigned long cmd_phase_addr, data_phase_addr, end_cmd, i;
>> +       unsigned long timeout = jiffies + PL353_NAND_DEV_BUSY_TIMEOUT;
>> +
>> +       if (xnand->end_cmd_pending) {
>> +               /*
>> +                * Check for end command if this command request is same as the
>> +                * pending command then return
>> +                */
>> +               if (xnand->end_cmd == command) {
>> +                       xnand->end_cmd = 0;
>> +                       xnand->end_cmd_pending = 0;
>> +                       return;
>> +               }
>> +       }
>> +
>> +       /* Emulate NAND_CMD_READOOB for large page device */
>> +       if ((mtd->writesize > PL353_NAND_ECC_SIZE) &&
>> +           (command == NAND_CMD_READOOB)) {
>> +               column += mtd->writesize;
>> +               command = NAND_CMD_READ0;
>> +       }
>> +
>> +       /* Get the command format */
>> +       for (i = 0; (pl353_nand_commands[i].start_cmd != NAND_CMD_NONE ||
>> +                    pl353_nand_commands[i].end_cmd != NAND_CMD_NONE); i++)
>> +               if (command == pl353_nand_commands[i].start_cmd)
>> +                       curr_cmd = &pl353_nand_commands[i];
>> +
>> +       if (curr_cmd == NULL)
>> +               return;
>> +
>> +       /* Clear interrupt */
>> +       pl353_smc_clr_nand_int();
>> +
>> +       /* Get the command phase address */
>> +       if (curr_cmd->end_cmd_valid == PL353_NAND_CMD_PHASE)
>> +               end_cmd_valid = 1;
>> +
>> +       if (curr_cmd->end_cmd == NAND_CMD_NONE)
>> +               end_cmd = 0x0;
>> +       else
>> +               end_cmd = curr_cmd->end_cmd;
>> +
>> +       cmd_phase_addr = (unsigned long __force)xnand->nand_base        |
>> +                        (curr_cmd->addr_cycles << ADDR_CYCLES_SHIFT)    |
>> +                        (end_cmd_valid << END_CMD_VALID_SHIFT)          |
>> +                        (COMMAND_PHASE)                                 |
>> +                        (end_cmd << END_CMD_SHIFT)                      |
>> +                        (curr_cmd->start_cmd << START_CMD_SHIFT);
>> +
>> +       cmd_addr = (void __iomem * __force)cmd_phase_addr;
>> +
>> +       /* Get the data phase address */
>> +       end_cmd_valid = 0;
>> +
>> +       data_phase_addr = (unsigned long __force)xnand->nand_base       |
>> +                         (0x0 << CLEAR_CS_SHIFT)                         |
>> +                         (end_cmd_valid << END_CMD_VALID_SHIFT)          |
>> +                         (DATA_PHASE)                                    |
>> +                         (end_cmd << END_CMD_SHIFT)                      |
>> +                         (0x0 << ECC_LAST_SHIFT);
>> +
>> +       chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
>> +       chip->IO_ADDR_W = chip->IO_ADDR_R;
>> +
>> +       /* Command phase AXI write */
>> +       /* Read & Write */
>> +       if (column != -1 && page_addr != -1) {
>> +               /* Adjust columns for 16 bit bus width */
>> +               if (chip->options & NAND_BUSWIDTH_16)
>> +                       column >>= 1;
>> +               cmd_data = column;
>> +               if (mtd->writesize > PL353_NAND_ECC_SIZE) {
>> +                       cmd_data |= page_addr << 16;
>> +                       /* Another address cycle for devices > 128MiB */
>> +                       if (chip->chipsize > (128 << 20)) {
>> +                               pl353_nand_write32(cmd_addr, cmd_data);
>> +                               cmd_data = (page_addr >> 16);
>> +                       }
>> +               } else {
>> +                       cmd_data |= page_addr << 8;
>> +               }
>> +       } else if (page_addr != -1) {
>> +               /* Erase */
>> +               cmd_data = page_addr;
>> +       } else if (column != -1) {
>> +               /*
>> +                * Change read/write column, read id etc
>> +                * Adjust columns for 16 bit bus width
>> +                */
>> +               if ((chip->options & NAND_BUSWIDTH_16) &&
>> +                       ((command == NAND_CMD_READ0) ||
>> +                       (command == NAND_CMD_SEQIN) ||
>> +                       (command == NAND_CMD_RNDOUT) ||
>> +                       (command == NAND_CMD_RNDIN)))
>> +                               column >>= 1;
>> +               cmd_data = column;
>> +       }
>> +
>> +       pl353_nand_write32(cmd_addr, cmd_data);
>> +
>> +       if (curr_cmd->end_cmd_valid) {
>> +               xnand->end_cmd = curr_cmd->end_cmd;
>> +               xnand->end_cmd_pending = 1;
>> +       }
>> +
>> +       ndelay(100);
>> +
>> +       if ((command == NAND_CMD_READ0) ||
>> +           (command == NAND_CMD_RESET) ||
>> +           (command == NAND_CMD_PARAM) ||
>> +           (command == NAND_CMD_GET_FEATURES)) {
>> +
>> +               /* Wait till the device is ready or timeout */
>> +               do {
>> +                       if (chip->dev_ready(mtd))
>> +                               break;
>> +                       else
>> +                               cpu_relax();
>> +               } while (!time_after_eq(jiffies, timeout));
>> +
>> +               if (time_after_eq(jiffies, timeout))
>> +                       pr_err("%s timed out\n", __func__);
>> +               return;
>> +       }
>> +}
>> +
>> +/**
>> + * pl353_nand_read_buf - read chip data into buffer
>> + * @mtd:       Pointer to the mtd info structure
>> + * @buf:       Pointer to the buffer to store read data
>> + * @len:       Number of bytes to read
>> + */
>> +static void pl353_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
>> +{
>> +       int i;
>> +       struct nand_chip *chip = mtd->priv;
>> +       unsigned long *ptr = (unsigned long *)buf;
>> +
>> +       len >>= 2;
>> +       for (i = 0; i < len; i++)
>> +               ptr[i] = readl(chip->IO_ADDR_R);
>> +}
>> +
>> +/**
>> + * pl353_nand_write_buf - write buffer to chip
>> + * @mtd:       Pointer to the mtd info structure
>> + * @buf:       Pointer to the buffer to store read data
>> + * @len:       Number of bytes to write
>> + */
>> +static void pl353_nand_write_buf(struct mtd_info *mtd, const uint8_t *buf,
>> +                               int len)
>> +{
>> +       int i;
>> +       struct nand_chip *chip = mtd->priv;
>> +       unsigned long *ptr = (unsigned long *)buf;
>> +
>> +       len >>= 2;
>> +
>> +       for (i = 0; i < len; i++)
>> +               writel(ptr[i], chip->IO_ADDR_W);
>> +}
>> +
>> +/**
>> + * pl353_nand_device_ready - Check device ready/busy line
>> + * @mtd:       Pointer to the mtd_info structure
>> + *
>> + * Return:     0 on busy or 1 on ready state
>> + */
>> +static int pl353_nand_device_ready(struct mtd_info *mtd)
>> +{
>> +       if (pl353_smc_get_nand_int_status_raw()) {
>> +               pl353_smc_clr_nand_int();
>> +               return 1;
>> +       }
>> +       return 0;
>> +}
>> +
>> +/**
>> + * pl353_nand_detect_ondie_ecc - Get the flash ondie ecc state
>> + * @mtd:       Pointer to the mtd_info structure
>> + *
>> + * This function enables the ondie ecc for the Micron ondie ecc capable devices
>> + *
>> + * Return:     1 on detect, 0 if fail to detect
>> + */
>> +static int pl353_nand_detect_ondie_ecc(struct mtd_info *mtd)
>> +{
>> +       struct nand_chip *nand_chip = mtd->priv;
>> +       u8 maf_id, dev_id, i, get_feature;
>> +       u8 set_feature[4] = { 0x08, 0x00, 0x00, 0x00 };
>> +
>> +       /* Check if On-Die ECC flash */
>> +       nand_chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
>> +       nand_chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
>> +
>> +       /* Read manufacturer and device IDs */
>> +       maf_id = readb(nand_chip->IO_ADDR_R);
>> +       dev_id = readb(nand_chip->IO_ADDR_R);
>> +
>> +       if ((maf_id == NAND_MFR_MICRON) &&
>> +           ((dev_id == 0xf1) || (dev_id == 0xa1) ||
>> +            (dev_id == 0xb1) || (dev_id == 0xaa) ||
>> +            (dev_id == 0xba) || (dev_id == 0xda) ||
>> +            (dev_id == 0xca) || (dev_id == 0xac) ||
>> +            (dev_id == 0xbc) || (dev_id == 0xdc) ||
>> +            (dev_id == 0xcc) || (dev_id == 0xa3) ||
>> +            (dev_id == 0xb3) ||
>> +            (dev_id == 0xd3) || (dev_id == 0xc3))) {
>> +
>> +               nand_chip->cmdfunc(mtd, NAND_CMD_GET_FEATURES,
>> +                                  ONDIE_ECC_FEATURE_ADDR, -1);
>> +               get_feature = readb(nand_chip->IO_ADDR_R);
>> +
>> +               if (get_feature & 0x08) {
>> +                       return 1;
>> +               } else {
>> +                       nand_chip->cmdfunc(mtd, NAND_CMD_SET_FEATURES,
>> +                                          ONDIE_ECC_FEATURE_ADDR, -1);
>> +                       for (i = 0; i < 4; i++)
>> +                               writeb(set_feature[i], nand_chip->IO_ADDR_W);
>> +
>> +                       ndelay(1000);
>> +
>> +                       nand_chip->cmdfunc(mtd, NAND_CMD_GET_FEATURES,
>> +                                          ONDIE_ECC_FEATURE_ADDR, -1);
>> +                       get_feature = readb(nand_chip->IO_ADDR_R);
>> +
>> +                       if (get_feature & 0x08)
>> +                               return 1;
>> +
>> +               }
>> +       }
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * pl353_nand_ecc_init - Initialize the ecc information as per the ecc mode
>> + * @mtd:       Pointer to the mtd_info structure
>> + * @ondie_ecc_state:   ondie ecc status
>> + *
>> + * This function initializes the ecc block and functional pointers as per the
>> + * ecc mode
>> + */
>> +static void pl353_nand_ecc_init(struct mtd_info *mtd, int ondie_ecc_state)
>> +{
>> +       struct nand_chip *nand_chip = mtd->priv;
>> +
>> +       nand_chip->ecc.mode = NAND_ECC_HW;
>> +       nand_chip->ecc.read_oob = pl353_nand_read_oob;
>> +       nand_chip->ecc.read_page_raw = pl353_nand_read_page_raw;
>> +       nand_chip->ecc.strength = 1;
>> +       nand_chip->ecc.write_oob = pl353_nand_write_oob;
>> +       nand_chip->ecc.write_page_raw = pl353_nand_write_page_raw;
>> +
>> +       if (ondie_ecc_state) {
>> +               /* bypass the controller ECC block */
>> +               pl353_smc_set_ecc_mode(PL353_SMC_ECCMODE_BYPASS);
>> +
>> +               /*
>> +                * The software ECC routines won't work with the
>> +                * SMC controller
>> +                */
>> +               nand_chip->ecc.bytes = 0;
>> +               nand_chip->ecc.layout = &ondie_nand_oob_64;
>> +               nand_chip->ecc.read_page = pl353_nand_read_page_raw;
>> +               nand_chip->ecc.write_page = pl353_nand_write_page_raw;
>> +               nand_chip->ecc.size = mtd->writesize;
>> +               /*
>> +                * On-Die ECC spare bytes offset 8 is used for ECC codes
>> +                * Use the BBT pattern descriptors
>> +                */
>> +               nand_chip->bbt_td = &bbt_main_descr;
>> +               nand_chip->bbt_md = &bbt_mirror_descr;
>> +       } else {
>> +               /* Hardware ECC generates 3 bytes ECC code for each 512 bytes */
>> +               nand_chip->ecc.bytes = 3;
>> +               nand_chip->ecc.calculate = pl353_nand_calculate_hwecc;
>> +               nand_chip->ecc.correct = pl353_nand_correct_data;
>> +               nand_chip->ecc.hwctl = NULL;
>> +               nand_chip->ecc.read_page = pl353_nand_read_page_hwecc;
>> +               nand_chip->ecc.size = PL353_NAND_ECC_SIZE;
>> +               nand_chip->ecc.write_page = pl353_nand_write_page_hwecc;
>> +
>> +               pl353_smc_set_ecc_pg_size(mtd->writesize);
>> +               switch (mtd->writesize) {
>> +               case 512:
>> +               case 1024:
>> +               case 2048:
>> +                       pl353_smc_set_ecc_mode(PL353_SMC_ECCMODE_APB);
>> +                       break;
>> +               default:
>> +                       /*
>> +                        * The software ECC routines won't work with the
>> +                        * SMC controller
>> +                        */
>> +                       nand_chip->ecc.calculate = nand_calculate_ecc;
>> +                       nand_chip->ecc.correct = nand_correct_data;
>> +                       nand_chip->ecc.read_page = pl353_nand_read_page_swecc;
>> +                       nand_chip->ecc.write_page = pl353_nand_write_page_swecc;
>> +                       nand_chip->ecc.size = 256;
>> +                       break;
>> +               }
>> +
>> +               if (mtd->oobsize == 16)
>> +                       nand_chip->ecc.layout = &nand_oob_16;
>> +               else if (mtd->oobsize == 64)
>> +                       nand_chip->ecc.layout = &nand_oob_64;
>> +       }
>> +}
>> +
>> +/**
>> + * pl353_nand_probe - Probe method for the NAND driver
>> + * @pdev:      Pointer to the platform_device structure
>> + *
>> + * This function initializes the driver data structures and the hardware.
>> + *
>> + * Return:     0 on success or error value on failure
>> + */
>> +static int pl353_nand_probe(struct platform_device *pdev)
>> +{
>> +       struct pl353_nand_info *xnand;
>> +       struct mtd_info *mtd;
>> +       struct nand_chip *nand_chip;
>> +       struct resource *res;
>> +       struct mtd_part_parser_data ppdata;
>> +       int ondie_ecc_state;
>> +
>> +       xnand = devm_kzalloc(&pdev->dev, sizeof(*xnand), GFP_KERNEL);
>> +       if (!xnand)
>> +               return -ENOMEM;
>> +
>> +       /* Map physical address of NAND flash */
>> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> +       xnand->nand_base = devm_ioremap_resource(&pdev->dev, res);
>> +       if (IS_ERR(xnand->nand_base))
>> +               return PTR_ERR(xnand->nand_base);
>> +
>> +       /* Link the private data with the MTD structure */
>> +       mtd = &xnand->mtd;
>> +       nand_chip = &xnand->chip;
>> +
>> +       nand_chip->priv = xnand;
>> +       mtd->priv = nand_chip;
>> +       mtd->owner = THIS_MODULE;
>> +       mtd->name = PL353_NAND_DRIVER_NAME;
>> +
>> +       /* Set address of NAND IO lines */
>> +       nand_chip->IO_ADDR_R = xnand->nand_base;
>> +       nand_chip->IO_ADDR_W = xnand->nand_base;
>> +
>> +       /* Set the driver entry points for MTD */
>> +       nand_chip->cmdfunc = pl353_nand_cmd_function;
>> +       nand_chip->dev_ready = pl353_nand_device_ready;
>> +       nand_chip->select_chip = pl353_nand_select_chip;
>> +
>> +       /* If we don't set this delay driver sets 20us by default */
>> +       nand_chip->chip_delay = 30;
>> +
>> +       /* Buffer read/write routines */
>> +       nand_chip->read_buf = pl353_nand_read_buf;
>> +       nand_chip->write_buf = pl353_nand_write_buf;
>> +
>> +       /* Set the device option and flash width */
>> +       nand_chip->options = NAND_BUSWIDTH_AUTO;
>> +       nand_chip->bbt_options = NAND_BBT_USE_FLASH;
>> +
>> +       platform_set_drvdata(pdev, xnand);
>> +
>> +       ondie_ecc_state = pl353_nand_detect_ondie_ecc(mtd);
>> +
>> +       /* first scan to find the device and get the page size */
>> +       if (nand_scan_ident(mtd, 1, NULL)) {
>> +               dev_err(&pdev->dev, "nand_scan_ident for NAND failed\n");
>> +               return -ENXIO;
>> +       }
>> +
>> +       pl353_nand_ecc_init(mtd, ondie_ecc_state);
>> +       if (nand_chip->options & NAND_BUSWIDTH_16)
>> +               pl353_smc_set_buswidth(PL353_SMC_MEM_WIDTH_16);
>> +
>> +       /* second phase scan */
>> +       if (nand_scan_tail(mtd)) {
>> +               dev_err(&pdev->dev, "nand_scan_tail for NAND failed\n");
>> +               return -ENXIO;
>> +       }
>> +
>> +       ppdata.of_node = pdev->dev.of_node;
>> +
>> +       mtd_device_parse_register(&xnand->mtd, NULL, &ppdata, NULL, 0);
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * pl353_nand_remove - Remove method for the NAND driver
>> + * @pdev:      Pointer to the platform_device structure
>> + *
>> + * This function is called if the driver module is being unloaded. It frees all
>> + * resources allocated to the device.
>> + *
>> + * Return:     0 on success or error value on failure
>> + */
>> +static int pl353_nand_remove(struct platform_device *pdev)
>> +{
>> +       struct pl353_nand_info *xnand = platform_get_drvdata(pdev);
>> +
>> +       /* Release resources, unregister device */
>> +       nand_release(&xnand->mtd);
>> +       /* kfree(NULL) is safe */
>> +       kfree(xnand->parts);
>> +
>> +       return 0;
>> +}
>> +
>> +/* Match table for device tree binding */
>> +static const struct of_device_id pl353_nand_of_match[] = {
>> +       { .compatible = "arm,pl353-nand-r2p1" },
>> +       {},
>> +};
>> +MODULE_DEVICE_TABLE(of, pl353_nand_of_match);
>> +
>> +/*
>> + * pl353_nand_driver - This structure defines the NAND subsystem platform driver
>> + */
>> +static struct platform_driver pl353_nand_driver = {
>> +       .probe          = pl353_nand_probe,
>> +       .remove         = pl353_nand_remove,
>> +       .driver         = {
>> +               .name   = PL353_NAND_DRIVER_NAME,
>> +               .owner  = THIS_MODULE,
>> +               .of_match_table = pl353_nand_of_match,
>> +       },
>> +};
>> +
>> +module_platform_driver(pl353_nand_driver);
>> +
>> +MODULE_AUTHOR("Xilinx, Inc.");
>> +MODULE_ALIAS("platform:" PL353_NAND_DRIVER_NAME);
>> +MODULE_DESCRIPTION("ARM PL353 NAND Flash Driver");
>> +MODULE_LICENSE("GPL");
>> --
>> 1.7.4
>>
>>
>>
>> ______________________________________________________
>> Linux MTD discussion mailing list
>> http://lists.infradead.org/mailman/listinfo/linux-mtd/
>
>
>
> --
> Ezequiel García, VanguardiaSur
> www.vanguardiasur.com.ar



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