#ifndef SPIFLASH_H
#define SPIFLASH_H

#include <inttypes.h>
#include <stddef.h>
#include <string.h>

#include "fwimg.h"

/* SPI flash command opcodes */
enum romcmd {
    /* Standard SPI mode commands */
    ROM_WRITE_ENABLE			= 0x06,
    ROM_VOLATILE_SR_WRITE_ENABLE	= 0x50,
    ROM_WRITE_DISABLE			= 0x04,
    ROM_RELEASE_POWERDOWN_ID		= 0xab,
    ROM_MANUFACTURER_DEVICE_ID		= 0x90,
    ROM_JEDEC_ID			= 0x9f,
    ROM_READ_UNIQUE_ID			= 0x4b,
    ROM_READ_DATA			= 0x03, /* DO NOT USE */
    ROM_READ_DATA_32BIT			= 0x13, /* DO NOT USE */
    ROM_FAST_READ			= 0x0b,
    ROM_FAST_READ_32BIT			= 0x0c,
    ROM_PAGE_PROGRAM			= 0x02,
    ROM_PAGE_PROGRAM_32BIT		= 0x12,
    ROM_ERASE_4K			= 0x20,
    ROM_ERASE_4K_32BIT			= 0x21,
    ROM_ERASE_32K			= 0x52,
    ROM_ERASE_64K			= 0xd8,
    ROM_ERASE_64K_32BIT			= 0xdc,
    ROM_ERASE_ALL			= 0xc7,
    ROM_READ_SR1			= 0x05,
    ROM_WRITE_SR1			= 0x01,
    ROM_READ_SR2			= 0x35,
    ROM_WRITE_SR2			= 0x31,
    ROM_READ_SR3			= 0x15,
    ROM_WRITE_SR3			= 0x11,
    ROM_READ_EAR			= 0xc8, /* Extended address register */
    ROM_WRITE_EAR			= 0xc5,
    ROM_READ_SFDP			= 0x5a,
    ROM_ERASE_SECURITY			= 0x44,
    ROM_PROGRAM_SECURITY		= 0x42,
    ROM_READ_SECURITY			= 0x48,
    ROM_GLOBAL_BLOCK_LOCK		= 0x7e,
    ROM_GLOBAL_BLOCK_UNLOCK		= 0x98,
    ROM_READ_BLOCK_LOCK			= 0x3d,
    ROM_ONE_BLOCK_LOCK			= 0x36,
    ROM_ONE_BLOCK_UNLOCK		= 0x39,
    ROM_ERASE_PROGRAM_SUSPEND		= 0x75,
    ROM_ERASE_PROGRAM_RESUME		= 0x7a,
    ROM_POWER_DOWN			= 0xb9,
    ROM_ENTER_32BIT			= 0xb7,
    ROM_LEAVE_32BIT			= 0xe9,
    ROM_ENTER_QPI			= 0x48,
    ROM_ENABLE_RESET			= 0x66,
    ROM_RESET				= 0x99,

    /* Dual SPI commands */
    ROM_FAST_READ_DUAL			= 0x3b,
    ROM_FAST_READ_DUAL_32BIT		= 0x3c
};

#define SPIFLASH_SFDP_SIZE	256

/*
 * A page is an amount that can be programmed in one operation.
 * A sector is the minimum amount that can be erased in one operation.
 * A block is the optimal amount that can be erased in one operation.
 *
 * These are defined in hardware!
 */
#define SPIFLASH_PAGE_SHIFT	8 /* May be smaller than an actual page */
#define SPIFLASH_PAGE_SIZE	(1 << SPIFLASH_PAGE_SHIFT)
#define SPIFLASH_SECTOR_SHIFT	12
#define SPIFLASH_SECTOR_SIZE	(1 << SPIFLASH_SECTOR_SHIFT)
#define SPIFLASH_BLOCK_SHIFT	16
#define SPIFLASH_BLOCK_SIZE	(1 << SPIFLASH_BLOCK_SHIFT)

/*
 * Interface to the host. This structure should be passed in to the
 * initialization routine and will not be modified by the spiflash
 * routines.
 *
 * The spiflash code is reentrant if there are multiple SPI flash
 * devices. None are timing critical and may be preempted at any
 * time if applicable. When CS# is active (during spi_read or spi_write),
 * it MUST NOT be deasserted; if the bus is shared HOLD# can be asserted
 * (without deasserting CS#) to make the device release the bus without
 * affecting the state of the device.
 *
 * CS# will not be asserted while running in the core code or when
 * blocking for I/O; the host is obviously allowed to prefetch I/O
 * within the above constraints if the bus is shared.
 *
 * A private cookie pointer is passed to each function; this can be a
 * pointer back to the spiflash_ops structure, but does not have to
 * be.
 */
struct spiflash_ops {
    /*
     * Perform a SPI write operation. The SPI write operation consists of:
     * 1. Assert CS# (and deassert HOLD# if applicable)
     * 2. Transmit the command bytes (discard MISO input)
     * 3. Transmit the data bytes (discard MISO input)
     * 4. Deassert CS#
     * 5. Wait tCHSL (see SPI data table below)
     *
     * The number of data bytes may be zero. Note that the command
     * and data operations are identical and are separated only to
     * avoid unnecessary data copies.
     *
     * If this returns nonzero, no further operations are performed
     * and the top-level flash routine terminates immediately with
     * the returned value as a status code.
     *
     * It is not required that this routine blocks until tCHSL
     * is satisfied, however, the host is responsible to not assert
     * CS# again until tCHSL is satisfied. The SPI clock may run
     * or not during that time period.
     *
     * The SPI flash supports SPI modes 0 and 3.
     */
    int (*spi_write)(void *cookie,
		     const void *cmd, unsigned int cmd_len,
		     const void *data, unsigned int data_len,
		     int tshsl);

    /*
     * Perform a SPI read operation. The SPI read operation consists of:
     * 1. Assert CS# (and deassert HOLD# if applicable)
     * 2. Transmit the command bytes (discard MISO input)
     * 3. Receive the data bytes (MOSI is don't care)
     * 4. Deassert CS#
     * 5. Wait tCHSL (see SPI data table below)
     *
     * The number of data bytes may be zero. Note that the command
     * and data operations are identical and are separated only to
     * avoid unnecessary data copies.
     *
     * If this returns nonzero, no further operations are performed
     * and the top-level flash routine terminates immediately with
     * the returned value as a status code.
     *
     * It is not required that this routine blocks until tCHSL
     * is satisfied, however, the host is responsible to not assert
     * CS# again until tCHSL is satisfied. The SPI clock may run
     * or not during that time period.
     *
     * The SPI flash supports SPI modes 0 and 3.
     */
    int (*spi_read)(void *cookie,
		    const void *cmd, unsigned int cmd_len,
		    void *data, unsigned int data_len,
		    int tshsl);

    /*
     * Inform the host that the spiflash code is waiting for an
     * program or erase operation to complete. This can be used to
     * yield the host for other operations.
     *
     * The value passed in is the corresponding from the SPI data
     * table below; these are arbitrary cookies/units as far as the
     * spiflash code is concerned.
     *
     * This function may be NULL, in which case the SPI flash is polled
     * continously.
     */
    void (*yield)(void *cookie, int delay);
};

/*
 * This table provides some parameters for the SPI flash.
 */
enum spiflash_addr_mode {
    SPIFLASH_ADDR_DYNAMIC,	/* 24-bit for < 16 MB, otherwise 32 bit */
    SPIFLASH_ADDR_24BIT,	/* 24-bit addressing only */
    SPIFLASH_ADDR_32BIT		/* 32-bit addressing only */
};

struct spiflash_param {
    /*
     * Addressing mode (see above.) If SPIFLASH_ADDR_DYNAMIC is
     * specified (default), the chip is assumed to be in 24-bit-default
     * mode, and 32-bit opcodes will be used as needed.
     */
    enum spiflash_addr_mode addr;

    /*
     * CS# deselect times passed to spi_read() and spi_write().
     * Arbitrary units or cookies that are only interpreted by
     * the spi_read and spi_write routines.
     */
    int tshsl;			/* All other operations */
    int tshsl1;			/* Read operations */
    int tshsl2;			/* Erase, Program, and Write operations */

    /*
     * Delay values to pass to the yield operation. Arbitrary units
     * or cookies that are only interpreted by the yield routine.
     *
     * Not all of these are used by the current code, but are specified
     * for future-proofing reasons.
     */
    int trst;			/* Reset command to next instruction */
    int tw;			/* Write Status Register Time */
    int tpp;			/* Page Program Time */
    int tse;			/* Sector Erase Time (4K) */
    int tbe1;			/* Block Erase Time (32K) */
    int tbe2;			/* Block Erase Time (64K) */
    int tce;			/* Chip Erase Time */
};

/* Common structure for the above */
struct spiflash {
    /*
     * Read input data for flash write. Return the number of bytes
     * read.  A short read or a 0 byte return value represents end of
     * file/end of data; a negative value is treated as 0, and will be
     * returned from the top-level operation as a status code.
     *
     * It is not required to detect end of input if and only if the
     * input is a gzip file, as in that case the gzip data will contain
     * an end of stream indicator.
     *
     * The buffer initially passed to this function will always be
     * aligned to a malloc() alignment boundary; it will preserve
     * alignment boundaries if and only if short read returns only byte
     * counts in multiple of those alignment boundaries.
     *
     * If there is a memory buffer available containing full or
     * partial input data on entry, pass it to spiflash_flash_file();
     * If this memory buffer contains all available input, this
     * function can be NULL.
     *
     * A partial memory buffer must contain a full stream header block.
     */
    int (*read_data)(void *cookie, void *buf, unsigned int bufsize);
    void *cookie;		/* Pointer passed to spiflash_ops functions */

    /*
     * Operations on the SPI flash itself; if ops == NULL then this is a
     * dry run operation.
     */
    const struct spiflash_ops *ops;
    const struct spiflash_param *param;

    const char *target;		/* What are we programming? */
};

/*
 * Additional error codes
 */
#define SPIFLASH_ERR_ERASE_FAILED	(-7)
#define SPIFLASH_ERR_PROGRAM_FAILED	(-8)
#define SPIFLASH_ERR_WRITE_PROTECT	(-9)
#define SPIFLASH_ERR_NOT_READY		(-10)
#define SPIFLASH_ERR_DETECT		(-11)

/*
 * Top-level operations. These may return an error value from the ops
 * functions, any of the negative error values defined in zlib.h,
 * or one of the above error codes.
 */
int spiflash_flash_file(const struct spiflash *flash,
			void *data, size_t datalen);

/*
 * Flash a single region of data to the SPI flash.
 */
int spiflash_flash_data(const struct spiflash *flash, uint32_t addr,
			const void *data, size_t datalen);

/*
 * Read identifying data from SPI flash.
 */
#define SPIFLASH_ID_LEN 8
int spiflash_read_id(const struct spiflash *flash, void *id);

#define SPIFLASH_VDID_LEN 2
int spiflash_read_vdid(const struct spiflash *flash, void *vdid);

#endif