/*      $NetBSD: cfi.c,v 1.9 2019/02/06 04:20:40 mrg Exp $      */
/*-
 * Copyright (c) 2011 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Cliff Neighbors.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "opt_flash.h"
#include "opt_nor.h"
#include "opt_cfi.h"

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: cfi.c,v 1.9 2019/02/06 04:20:40 mrg Exp $"); 

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/cdefs.h>
#include <sys/device.h>
#include <sys/endian.h>

#include <sys/bus.h>
        
#include <dev/nor/nor.h>
#include <dev/nor/cfi.h>
#include <dev/nor/cfi_0002.h>


static int  cfi_scan_media(device_t self, struct nor_chip *chip);
static void cfi_init(device_t);
static void cfi_select(device_t, bool);
static void cfi_read_1(device_t, flash_off_t, uint8_t *);
static void cfi_read_2(device_t, flash_off_t, uint16_t *);
static void cfi_read_4(device_t, flash_off_t, uint32_t *);
static void cfi_read_buf_1(device_t, flash_off_t, uint8_t *, size_t);
static void cfi_read_buf_2(device_t, flash_off_t, uint16_t *, size_t);
static void cfi_read_buf_4(device_t, flash_off_t, uint32_t *, size_t);
static void cfi_write_1(device_t, flash_off_t, uint8_t);
static void cfi_write_2(device_t, flash_off_t, uint16_t);
static void cfi_write_4(device_t, flash_off_t, uint32_t);
static void cfi_write_buf_1(device_t, flash_off_t, const uint8_t *, size_t);
static void cfi_write_buf_2(device_t, flash_off_t, const uint16_t *, size_t);
static void cfi_write_buf_4(device_t, flash_off_t, const uint32_t *, size_t);
static uint8_t cfi_read_qry(struct cfi * const, bus_size_t);
static bool cfi_jedec_id(struct cfi * const);
static bool cfi_emulate(struct cfi * const);
static const struct cfi_jedec_tab * cfi_jedec_search(struct cfi *);
static void cfi_jedec_fill(struct cfi * const,
        const struct cfi_jedec_tab *);
#if defined(CFI_DEBUG_JEDEC) || defined(CFI_DEBUG_QRY)
static void cfi_hexdump(flash_off_t, void * const, u_int, u_int);
#endif

#define LOG2_64K        16
#define LOG2_128K       17
#define LOG2_256K       18
#define LOG2_512K       19
#define LOG2_1M         20
#define LOG2_2M         21
#define LOG2_4M         22
#define LOG2_8M         23
#define LOG2_16M        24
#define LOG2_32M        25
#define LOG2_64M        26
#define LOG2_128M       27
#define LOG2_256M       28
#define LOG2_512M       29
#define LOG2_1G         30
#define LOG2_2G         31
const struct cfi_jedec_tab cfi_jedec_tab[] = {
        {
                .jt_name = "Pm39LV512",
                .jt_mid = 0x9d,
                .jt_did = 0x1b,
                .jt_id_pri = 0,                         /* XXX */
                .jt_id_alt = 0,                         /* XXX */
                .jt_device_size = LOG2_64K,
                .jt_interface_code_desc = CFI_IFCODE_X8,
                .jt_erase_blk_regions = 1,
                .jt_erase_blk_info = {
                        { 4096/256, (64/4)-1 },
                },
                .jt_write_word_time_typ = 40,
                .jt_write_nbyte_time_typ = 0,
                .jt_erase_blk_time_typ = 55,
                .jt_erase_chip_time_typ = 55,
                .jt_write_word_time_max = 1,
                .jt_write_nbyte_time_max = 0,
                .jt_erase_blk_time_max = 1,
                .jt_erase_chip_time_max = 1,
        },
        {
                .jt_name = "Pm39LV010",
                .jt_mid = 0x9d,
                .jt_did = 0x1c,
                .jt_id_pri = 0,                         /* XXX */
                .jt_id_alt = 0,                         /* XXX */
                .jt_device_size = LOG2_128K,
                .jt_interface_code_desc = CFI_IFCODE_X8,
                .jt_erase_blk_regions = 1,
                .jt_erase_blk_info = {
                        { 4096/256, (128/4)-1 },
                },
                .jt_write_word_time_typ = 40,
                .jt_write_nbyte_time_typ = 0,
                .jt_erase_blk_time_typ = 55,
                .jt_erase_chip_time_typ = 55,
                .jt_write_word_time_max = 1,
                .jt_write_nbyte_time_max = 0,
                .jt_erase_blk_time_max = 1,
                .jt_erase_chip_time_max = 1,
        },
};


const struct nor_interface nor_interface_cfi = {
        .scan_media = cfi_scan_media,
        .init = cfi_init,
        .select = cfi_select,
        .read_1 = cfi_read_1,
        .read_2 = cfi_read_2,
        .read_4 = cfi_read_4,
        .read_buf_1 = cfi_read_buf_1,
        .read_buf_2 = cfi_read_buf_2,
        .read_buf_4 = cfi_read_buf_4,
        .write_1 = cfi_write_1,
        .write_2 = cfi_write_2,
        .write_4 = cfi_write_4,
        .write_buf_1 = cfi_write_buf_1,
        .write_buf_2 = cfi_write_buf_2,
        .write_buf_4 = cfi_write_buf_4,
        .read_page = NULL,                      /* cmdset */
        .program_page = NULL,                   /* cmdset */
        .busy = NULL,
        .private = NULL,
        .access_width = -1,
        .part_info = NULL,
        .part_num = -1,
};


/* only data[7..0] are used regardless of chip width */
#define cfi_unpack_1(n)                 ((n) & 0xff)

/* construct uint16_t */
#define cfi_unpack_2(b0, b1)                                            \
        ((cfi_unpack_1(b1) << 8) | cfi_unpack_1(b0))

/* construct uint32_t */
#define cfi_unpack_4(b0, b1, b2, b3)                                    \
        ((cfi_unpack_1(b3) << 24) |                                     \
         (cfi_unpack_1(b2) << 16) |                                     \
         (cfi_unpack_1(b1) <<  8) |                                     \
         (cfi_unpack_1(b0)))

#define cfi_unpack_qry(qryp, data)                                      \
    do {                                                                \
        (qryp)->qry[0] = cfi_unpack_1(data[0x10]);                      \
        (qryp)->qry[1] = cfi_unpack_1(data[0x11]);                      \
        (qryp)->qry[2] = cfi_unpack_1(data[0x12]);                      \
        (qryp)->id_pri = cfi_unpack_2(data[0x13], data[0x14]);          \
        (qryp)->addr_pri = cfi_unpack_2(data[0x15], data[0x16]);        \
        (qryp)->id_alt = cfi_unpack_2(data[0x17], data[0x18]);          \
        (qryp)->addr_alt = cfi_unpack_2(data[0x19], data[0x1a]);        \
        (qryp)->vcc_min = cfi_unpack_1(data[0x1b]);                     \
        (qryp)->vcc_max = cfi_unpack_1(data[0x1c]);                     \
        (qryp)->vpp_min = cfi_unpack_1(data[0x1d]);                     \
        (qryp)->vpp_max = cfi_unpack_1(data[0x1e]);                     \
        (qryp)->write_word_time_typ = cfi_unpack_1(data[0x1f]);         \
        (qryp)->write_nbyte_time_typ = cfi_unpack_1(data[0x20]);        \
        (qryp)->erase_blk_time_typ = cfi_unpack_1(data[0x21]);          \
        (qryp)->erase_chip_time_typ = cfi_unpack_1(data[0x22]);         \
        (qryp)->write_word_time_max = cfi_unpack_1(data[0x23]);         \
        (qryp)->write_nbyte_time_max = cfi_unpack_1(data[0x24]);        \
        (qryp)->erase_blk_time_max = cfi_unpack_1(data[0x25]);          \
        (qryp)->erase_chip_time_max = cfi_unpack_1(data[0x26]);         \
        (qryp)->device_size = cfi_unpack_1(data[0x27]);                 \
        (qryp)->interface_code_desc =                                   \
                cfi_unpack_2(data[0x28], data[0x29]);                   \
        (qryp)->write_nbyte_size_max =                                  \
                cfi_unpack_2(data[0x2a], data[0x2b]);                   \
        (qryp)->erase_blk_regions = cfi_unpack_1(data[0x2c]);           \
        u_int _i = 0x2d;                                                \
        const u_int _n = (qryp)->erase_blk_regions;                     \
        KASSERT(_n <= 4);                                               \
        for (u_int _r = 0; _r < _n; _r++, _i+=4) {                      \
                (qryp)->erase_blk_info[_r].y =                          \
                        cfi_unpack_2(data[_i+0], data[_i+1]);           \
                (qryp)->erase_blk_info[_r].z =                          \
                        cfi_unpack_2(data[_i+2], data[_i+3]);           \
        }                                                               \
    } while (0)

#define cfi_unpack_pri_0002(qryp, data)                                 \
    do {                                                                \
        (qryp)->pri.cmd_0002.pri[0] = cfi_unpack_1(data[0x00]);         \
        (qryp)->pri.cmd_0002.pri[1] = cfi_unpack_1(data[0x01]);         \
        (qryp)->pri.cmd_0002.pri[2] = cfi_unpack_1(data[0x02]);         \
        (qryp)->pri.cmd_0002.version_maj = cfi_unpack_1(data[0x03]);    \
        (qryp)->pri.cmd_0002.version_min = cfi_unpack_1(data[0x04]);    \
        (qryp)->pri.cmd_0002.asupt = cfi_unpack_1(data[0x05]);          \
        (qryp)->pri.cmd_0002.erase_susp = cfi_unpack_1(data[0x06]);     \
        (qryp)->pri.cmd_0002.sector_prot = cfi_unpack_1(data[0x07]);    \
        (qryp)->pri.cmd_0002.tmp_sector_unprot =                        \
                cfi_unpack_1(data[0x08]);                               \
        (qryp)->pri.cmd_0002.sector_prot_scheme =                       \
                cfi_unpack_1(data[0x09]);                               \
        (qryp)->pri.cmd_0002.simul_op = cfi_unpack_1(data[0x0a]);       \
        (qryp)->pri.cmd_0002.burst_mode_type = cfi_unpack_1(data[0x0b]);\
        (qryp)->pri.cmd_0002.page_mode_type = cfi_unpack_1(data[0x0c]); \
        (qryp)->pri.cmd_0002.acc_min = cfi_unpack_1(data[0x0d]);        \
        (qryp)->pri.cmd_0002.acc_max = cfi_unpack_1(data[0x0e]);        \
        (qryp)->pri.cmd_0002.wp_prot = cfi_unpack_1(data[0x0f]);        \
        /* XXX 1.3 stops here */                                        \
        (qryp)->pri.cmd_0002.prog_susp = cfi_unpack_1(data[0x10]);      \
        (qryp)->pri.cmd_0002.unlock_bypass = cfi_unpack_1(data[0x11]);  \
        (qryp)->pri.cmd_0002.sss_size = cfi_unpack_1(data[0x12]);       \
        (qryp)->pri.cmd_0002.soft_feat = cfi_unpack_1(data[0x13]);      \
        (qryp)->pri.cmd_0002.page_size = cfi_unpack_1(data[0x14]);      \
        (qryp)->pri.cmd_0002.erase_susp_time_max =                      \
                cfi_unpack_1(data[0x15]);                               \
        (qryp)->pri.cmd_0002.prog_susp_time_max =                       \
                cfi_unpack_1(data[0x16]);                               \
        (qryp)->pri.cmd_0002.embhwrst_time_max =                        \
                cfi_unpack_1(data[0x38]);                               \
        (qryp)->pri.cmd_0002.hwrst_time_max =                           \
                cfi_unpack_1(data[0x39]);                               \
    } while (0)

#define CFI_QRY_UNPACK_COMMON(cfi, data, type)                          \
    do {                                                                \
        struct cfi_query_data * const qryp = &cfi->cfi_qry_data;        \
                                                                        \
        memset(qryp, 0, sizeof(*qryp));                                 \
        cfi_unpack_qry(qryp, data);                                     \
                                                                        \
        switch (qryp->id_pri) {                                         \
        case 0x0002:                                                    \
                if ((cfi_unpack_1(data[qryp->addr_pri + 0]) == 'P') &&  \
                    (cfi_unpack_1(data[qryp->addr_pri + 1]) == 'R') &&  \
                    (cfi_unpack_1(data[qryp->addr_pri + 2]) == 'I')) {  \
                        type *pri_data = &data[qryp->addr_pri];         \
                        cfi_unpack_pri_0002(qryp, pri_data);            \
                        break;                                          \
                }                                                       \
        }                                                               \
    } while (0)

#ifdef CFI_DEBUG_QRY
# define CFI_DUMP_QRY(off, p, sz, stride)                               \
    do {                                                                \
        printf("%s: QRY data\n", __func__);                             \
        cfi_hexdump(off, p, sz, stride);                                \
    } while (0)
#else
# define CFI_DUMP_QRY(off, p, sz, stride)
#endif

#ifdef CFI_DEBUG_JEDEC
# define CFI_DUMP_JEDEC(off, p, sz, stride)                             \
    do {                                                                \
        printf("%s: JEDEC data\n", __func__);                           \
        cfi_hexdump(off, p, sz, stride);                                \
    } while (0)
#else
# define CFI_DUMP_JEDEC(off, p, sz, stride)
#endif


static void
cfi_chip_query_1(struct cfi * const cfi)
{
        uint8_t data[0x80];

        bus_space_read_region_1(cfi->cfi_bst, cfi->cfi_bsh, 0, data,
            __arraycount(data));
        CFI_DUMP_QRY(0, data, sizeof(data), 1);
        CFI_QRY_UNPACK_COMMON(cfi, data, uint8_t);
}

static void
cfi_chip_query_2(struct cfi * const cfi)
{
        uint16_t data[0x80];

        bus_space_read_region_2(cfi->cfi_bst, cfi->cfi_bsh, 0, data,
            __arraycount(data));
        CFI_DUMP_QRY(0, data, sizeof(data), 2);
        CFI_QRY_UNPACK_COMMON(cfi, data, uint16_t);
}

static void
cfi_chip_query_4(struct cfi * const cfi)
{
        uint32_t data[0x80];

        bus_space_read_region_4(cfi->cfi_bst, cfi->cfi_bsh, 0, data,
            __arraycount(data));
        CFI_DUMP_QRY(0, data, sizeof(data), 4);
        CFI_QRY_UNPACK_COMMON(cfi, data, uint32_t);
}

static void
cfi_chip_query_8(struct cfi * const cfi)
{
#ifdef NOTYET
        uint64_t data[0x80];

        bus_space_read_region_8(cfi->cfi_bst, cfi->cfi_bsh, 0, data,
            __arraycount(data));
        CFI_DUMP_QRY(0, data, sizeof(data), 8);
        CFI_QRY_UNPACK_COMMON(cfi, data, uint64_t);
#endif
}

/*
 * cfi_chip_query - detect a CFI chip
 *
 * fill in the struct cfi as we discover what's there
 */
static bool
cfi_chip_query(struct cfi * const cfi)
{
        const bus_size_t cfi_query_offset[] = {
                CFI_QUERY_MODE_ADDR,
                CFI_QUERY_MODE_ALT_ADDR
        };

        KASSERT(cfi != NULL);
        KASSERT(cfi->cfi_bst != NULL);

        for (int j=0; j < __arraycount(cfi_query_offset); j++) {

                cfi_reset_default(cfi);
                cfi_cmd(cfi, cfi_query_offset[j], CFI_QUERY_DATA);

                if (cfi_read_qry(cfi, 0x10) == 'Q' &&
                    cfi_read_qry(cfi, 0x11) == 'R' &&
                    cfi_read_qry(cfi, 0x12) == 'Y') {
                        switch(cfi->cfi_portwidth) {
                        case 0:
                                cfi_chip_query_1(cfi);
                                break;
                        case 1:
                                cfi_chip_query_2(cfi);
                                break;
                        case 2:
                                cfi_chip_query_4(cfi);
                                break;
                        case 3:
                                cfi_chip_query_8(cfi);
                                break;
                        default:
                                panic("%s: bad portwidth %d\n",
                                    __func__, cfi->cfi_portwidth);
                        }

                        switch (cfi->cfi_qry_data.id_pri) {
                        case 0x0002:
                                cfi->cfi_unlock_addr1 = CFI_AMD_UNLOCK_ADDR1;
                                cfi->cfi_unlock_addr2 = CFI_AMD_UNLOCK_ADDR2;
                                break;
                        default:
                                DPRINTF(("%s: unsupported CFI cmdset %#04x\n",
                                    __func__, cfi->cfi_qry_data.id_pri));
                                return false;
                        }

                        cfi->cfi_emulated = false;
                        return true;
                }
        }

        return false;
}

/*
 * cfi_probe - search for a CFI NOR trying various port & chip widths
 *
 * - gather CFI QRY and PRI data
 * - gather JEDEC ID data
 * - if cfi_chip_query() fails, emulate CFI using table data if possible,
 *   otherwise fail.
 *
 * NOTE:
 *   striped NOR chips design not supported yet
 */
bool
cfi_probe(struct cfi * const cfi)
{
        bool found;

        KASSERT(cfi != NULL);

        /* XXX set default unlock address for cfi_jedec_id() */
        cfi->cfi_unlock_addr1 = CFI_AMD_UNLOCK_ADDR1;
        cfi->cfi_unlock_addr2 = CFI_AMD_UNLOCK_ADDR2;

        for (u_int pw = 0; pw < 3; pw++) {
                for (u_int cw = 0; cw <= pw; cw++) {
                        cfi->cfi_portwidth = pw;
                        cfi->cfi_chipwidth = cw;
                        found = cfi_chip_query(cfi);
                        cfi_jedec_id(cfi);
                        if (! found)
                                found = cfi_emulate(cfi);
                        if (found)
                                goto exit_qry;
                }
        }

    exit_qry:
        cfi_reset_default(cfi);         /* exit QRY mode */
        return found;
}

bool
cfi_identify(struct cfi * const cfi)
{
        const bus_space_tag_t bst = cfi->cfi_bst;
        const bus_space_handle_t bsh = cfi->cfi_bsh;

        KASSERT(cfi != NULL);
        KASSERT(bst != NULL);

        memset(cfi, 0, sizeof(struct cfi));     /* XXX clean slate */
        cfi->cfi_bst = bst;             /* restore bus space */
        cfi->cfi_bsh = bsh;             /*  "       "   "    */

        return cfi_probe(cfi);
}

static int
cfi_scan_media(device_t self, struct nor_chip *chip)
{
        struct nor_softc *sc = device_private(self);
        KASSERT(sc != NULL);
        KASSERT(sc->sc_nor_if != NULL);
        struct cfi * const cfi = (struct cfi * const)sc->sc_nor_if->private;
        KASSERT(cfi != NULL);

        sc->sc_nor_if->access_width = cfi->cfi_portwidth;

        chip->nc_manf_id = cfi->cfi_id_data.id_mid;
        chip->nc_dev_id = cfi->cfi_id_data.id_did[0]; /* XXX 3 words */
        chip->nc_size = 1 << cfi->cfi_qry_data.device_size;

        /* size of line for Read Buf command */
        chip->nc_line_size = 1 << cfi->cfi_qry_data.pri.cmd_0002.page_size;

        /*
         * size of erase block
         * XXX depends on erase region
         */
        chip->nc_num_luns = 1;
        chip->nc_lun_blocks = cfi->cfi_qry_data.erase_blk_info[0].y + 1;
        chip->nc_block_size = cfi->cfi_qry_data.erase_blk_info[0].z ?
            cfi->cfi_qry_data.erase_blk_info[0].z * 256 : 128;

        switch (cfi->cfi_qry_data.id_pri) {
        case 0x0002:
                cfi_0002_init(sc, cfi, chip);
                break;
        }

        return 0;
}

void
cfi_init(device_t self)
{
        /* nothing */
}

static void
cfi_select(device_t self, bool select)
{
        /* nothing */
}

static void
cfi_read_1(device_t self, flash_off_t offset, uint8_t *datap)
{
}

static void
cfi_read_2(device_t self, flash_off_t offset, uint16_t *datap)
{
}

static void
cfi_read_4(device_t self, flash_off_t offset, uint32_t *datap)
{
}

static void
cfi_read_buf_1(device_t self, flash_off_t offset, uint8_t *datap, size_t size)
{
}

static void
cfi_read_buf_2(device_t self, flash_off_t offset, uint16_t *datap, size_t size)
{
}

static void
cfi_read_buf_4(device_t self, flash_off_t offset, uint32_t *datap, size_t size)
{
}

static void
cfi_write_1(device_t self, flash_off_t offset, uint8_t data)
{
}

static void
cfi_write_2(device_t self, flash_off_t offset, uint16_t data)
{
}

static void
cfi_write_4(device_t self, flash_off_t offset, uint32_t data)
{
}

static void
cfi_write_buf_1(device_t self, flash_off_t offset, const uint8_t *datap,
    size_t size)
{
}

static void
cfi_write_buf_2(device_t self, flash_off_t offset, const uint16_t *datap,
    size_t size)
{
}

static void
cfi_write_buf_4(device_t self, flash_off_t offset, const uint32_t *datap,
    size_t size)
{
}

/*
 * cfi_cmd - write a CFI command word.
 *
 * The offset 'off' is given for 64-bit port width and will be scaled
 * down to the actual port width of the chip.
 * The command word will be constructed out of 'val' regarding port- and
 * chip width.
 */
void
cfi_cmd(struct cfi * const cfi, bus_size_t off, uint32_t val)
{
        const bus_space_tag_t bst = cfi->cfi_bst;
        bus_space_handle_t bsh = cfi->cfi_bsh;
        uint64_t cmd;
        int cw, pw;

        off >>= 3 - cfi->cfi_portwidth;

        pw = 1 << cfi->cfi_portwidth;
        cw = 1 << cfi->cfi_chipwidth;
        cmd = 0;
        while (pw > 0) {
                cmd <<= cw << 3;
                cmd += val;
                pw -= cw;
        }

        DPRINTF(("%s: %p %x %x %" PRIx64 "\n", __func__, bst, bsh, off, cmd));

        switch (cfi->cfi_portwidth) {
        case 0:
                bus_space_write_1(bst, bsh, off, cmd);
                break;
        case 1:
                bus_space_write_2(bst, bsh, off, cmd);
                break;
        case 2:
                bus_space_write_4(bst, bsh, off, cmd);
                break;
#ifdef NOTYET
        case 3:
                bus_space_write_8(bst, bsh, off, cmd);
                break;
#endif
        default:
                panic("%s: bad portwidth %d bytes\n",
                        __func__, 1 << cfi->cfi_portwidth);
        }
}

static uint8_t
cfi_read_qry(struct cfi * const cfi, bus_size_t off)
{
        const bus_space_tag_t bst = cfi->cfi_bst;
        bus_space_handle_t bsh = cfi->cfi_bsh;
        uint8_t data;

        off <<= cfi->cfi_portwidth;

        switch (cfi->cfi_portwidth) {
        case 0:
                data = bus_space_read_1(bst, bsh, off);
                break;
        case 1:
                data = bus_space_read_2(bst, bsh, off);
                break;
        case 2:
                data = bus_space_read_4(bst, bsh, off);
                break;
        case 3:
                data = bus_space_read_8(bst, bsh, off);
                break;
        default:
                data = ~0;
                break;
        }
        return data;
}

/*
 * cfi_reset_default - when we don't know which command will work, use both
 */
void
cfi_reset_default(struct cfi * const cfi)
{

        cfi_cmd(cfi, CFI_ADDR_ANY, CFI_RESET_DATA);
        cfi_cmd(cfi, CFI_ADDR_ANY, CFI_ALT_RESET_DATA);
}

/*
 * cfi_reset_std - use standard reset command
 */
void
cfi_reset_std(struct cfi * const cfi)
{

        cfi_cmd(cfi, CFI_ADDR_ANY, CFI_RESET_DATA);
}

/*
 * cfi_reset_alt - use "alternate" reset command
 */
void
cfi_reset_alt(struct cfi * const cfi)
{

        cfi_cmd(cfi, CFI_ADDR_ANY, CFI_ALT_RESET_DATA);
}

static void
cfi_jedec_id_1(struct cfi * const cfi)
{
        struct cfi_jedec_id_data *idp = &cfi->cfi_id_data;
        uint8_t data[0x10];

        bus_space_read_region_1(cfi->cfi_bst, cfi->cfi_bsh, 0, data,
                __arraycount(data));

        CFI_DUMP_JEDEC(0, data, sizeof(data), 1);

        idp->id_mid = (uint16_t)data[0];
        idp->id_did[0] = (uint16_t)data[1];
        idp->id_did[1] = (uint16_t)data[0xe];
        idp->id_did[2] = (uint16_t)data[0xf];
        idp->id_prot_state = (uint16_t)data[2];
        idp->id_indicators = (uint16_t)data[3];

        /* software bits, upper and lower */
        idp->id_swb_lo = data[0xc];
        idp->id_swb_hi = data[0xd];

}

static void
cfi_jedec_id_2(struct cfi * const cfi)
{
        struct cfi_jedec_id_data *idp = &cfi->cfi_id_data;
        uint16_t data[0x10];

        bus_space_read_region_2(cfi->cfi_bst, cfi->cfi_bsh, 0, data,
                __arraycount(data));

        CFI_DUMP_JEDEC(0, data, sizeof(data), 1);

        idp->id_mid = data[0];
        idp->id_did[0] = data[1];
        idp->id_did[1] = data[0xe];
        idp->id_did[2] = data[0xf];
        idp->id_prot_state = data[2];
        idp->id_indicators = data[3];

        /* software bits, upper and lower
         * - undefined on S29GL-P
         * - defined   on S29GL-S
         */
        idp->id_swb_lo = data[0xc];
        idp->id_swb_hi = data[0xd];

}

static void
cfi_jedec_id_4(struct cfi * const cfi)
{
        struct cfi_jedec_id_data *idp = &cfi->cfi_id_data;
        uint32_t data[0x10];

        bus_space_read_region_4(cfi->cfi_bst, cfi->cfi_bsh, 0, data,
                __arraycount(data));

        CFI_DUMP_JEDEC(0, data, sizeof(data), 1);

        idp->id_mid = data[0] & 0xffff;
        idp->id_did[0] = data[1] & 0xffff;
        idp->id_did[1] = data[0xe] & 0xffff;
        idp->id_did[2] = data[0xf] & 0xffff;
        idp->id_prot_state = data[2] & 0xffff;
        idp->id_indicators = data[3] & 0xffff;

        /* software bits, upper and lower
         * - undefined on S29GL-P
         * - defined   on S29GL-S
         */
        idp->id_swb_lo = data[0xc] & 0xffff;
        idp->id_swb_hi = data[0xd] & 0xffff;

}

/*
 * cfi_jedec_id - get JEDEC ID info
 */
static bool
cfi_jedec_id(struct cfi * const cfi)
{

        DPRINTF(("%s\n", __func__));

        cfi_reset_default(cfi);
        cfi_cmd(cfi, cfi->cfi_unlock_addr1, 0xaa);
        cfi_cmd(cfi, cfi->cfi_unlock_addr2, 0x55);
        cfi_cmd(cfi, cfi->cfi_unlock_addr1, 0x90);

        switch(cfi->cfi_portwidth) {
        case 0:
                cfi_jedec_id_1(cfi);
                break;
        case 1:
                cfi_jedec_id_2(cfi);
                break;
        case 2:
                cfi_jedec_id_4(cfi);
                break;
#ifdef NOTYET
        case 3:
                cfi_jedec_id_8(cfi);
                break;
#endif
        default:
                panic("%s: bad portwidth %d bytes\n",
                        __func__, 1 << cfi->cfi_portwidth);
        }

        return true;
}

static bool
cfi_emulate(struct cfi * const cfi)
{
        bool found = false;
        const struct cfi_jedec_tab *jt = cfi_jedec_search(cfi);
        if (jt != NULL) {
                found = true;
                cfi->cfi_emulated = true;
                cfi_jedec_fill(cfi, jt);
        }
        return found;
}

/*
 * cfi_jedec_search - search cfi_jedec_tab[] for entry matching given JEDEC IDs
 */
static const struct cfi_jedec_tab *
cfi_jedec_search(struct cfi *cfi)
{
        struct cfi_jedec_id_data *idp = &cfi->cfi_id_data;

        for (u_int i=0; i < __arraycount(cfi_jedec_tab); i++) {
                const struct cfi_jedec_tab *jt = &cfi_jedec_tab[i];
                if ((jt->jt_mid == idp->id_mid) &&
                    (jt->jt_did == idp->id_did[0])) {
                        return jt;
                }
        }
        return NULL;
}

/*
 * cfi_jedec_fill - fill in cfi with info from table entry
 */
static void
cfi_jedec_fill(struct cfi *cfi, const struct cfi_jedec_tab *jt)
{

        cfi->cfi_name = jt->jt_name;

        struct cfi_query_data *qryp = &cfi->cfi_qry_data;
        memset(qryp, 0, sizeof(*qryp));
        qryp->id_pri = jt->jt_id_pri;
        qryp->id_alt = jt->jt_id_alt;
        qryp->interface_code_desc = jt->jt_interface_code_desc;
        qryp->write_word_time_typ = jt->jt_write_word_time_typ;
        qryp->write_nbyte_time_typ = jt->jt_write_nbyte_time_typ;
        qryp->erase_blk_time_typ = jt->jt_erase_blk_time_typ;
        qryp->erase_chip_time_typ = jt->jt_erase_chip_time_typ;
        qryp->write_word_time_max = jt->jt_write_word_time_max;
        qryp->write_nbyte_time_max = jt->jt_write_nbyte_time_max;
        qryp->erase_blk_time_max = jt->jt_erase_blk_time_max;
        qryp->erase_chip_time_max = jt->jt_erase_chip_time_max;
        qryp->device_size = jt->jt_device_size;
        qryp->interface_code_desc = jt->jt_interface_code_desc;
        qryp->write_nbyte_size_max = jt->jt_write_nbyte_size_max;
        qryp->erase_blk_regions = jt->jt_erase_blk_regions;
        for (u_int i=0; i < 4; i++)
                qryp->erase_blk_info[i] = jt->jt_erase_blk_info[i];

}

void
cfi_print(device_t self, struct cfi * const cfi)
{
        char pbuf[sizeof("XXXX MB")];
        struct cfi_query_data * const qryp = &cfi->cfi_qry_data;

        format_bytes(pbuf, sizeof(pbuf), 1 << qryp->device_size);
        if (cfi->cfi_emulated) {
                aprint_normal_dev(self, "%s NOR flash %s %s\n",
                        cfi->cfi_name, pbuf,
                        cfi_interface_desc_str(qryp->interface_code_desc));
        } else {
                aprint_normal_dev(self, "CFI NOR flash %s %s\n", pbuf,
                        cfi_interface_desc_str(qryp->interface_code_desc));
        }
#ifdef NOR_VERBOSE
        aprint_normal_dev(self, "manufacturer id %#x, device id %#x %#x %#x\n",
                cfi->cfi_id_data.id_mid,
                cfi->cfi_id_data.id_did[0],
                cfi->cfi_id_data.id_did[1],
                cfi->cfi_id_data.id_did[2]);
        aprint_normal_dev(self, "x%u device operating in %u-bit mode\n",
                8 << cfi->cfi_portwidth, 8 << cfi->cfi_chipwidth);
        aprint_normal_dev(self, "sw bits lo=%#x hi=%#x\n",
                cfi->cfi_id_data.id_swb_lo,
                cfi->cfi_id_data.id_swb_hi);
        aprint_normal_dev(self, "max multibyte write size %d\n",
                1 << qryp->write_nbyte_size_max);
        aprint_normal_dev(self, "%d Erase Block Region(s)\n",
                qryp->erase_blk_regions);
        for (u_int r=0; r < qryp->erase_blk_regions; r++) {
                size_t sz = qryp->erase_blk_info[r].z ?
                    qryp->erase_blk_info[r].z * 256 : 128;
                format_bytes(pbuf, sizeof(pbuf), sz);
                aprint_normal("    %d: %d blocks, size %s\n", r,
                        qryp->erase_blk_info[r].y + 1, pbuf);
        }
#endif

        switch (cfi->cfi_qry_data.id_pri) {
        case 0x0002:
                cfi_0002_print(self, cfi);
                break;
        }
}

#if defined(CFI_DEBUG_JEDEC) || defined(CFI_DEBUG_QRY)
void
cfi_hexdump(flash_off_t offset, void * const v, u_int count, u_int stride)
{
        uint8_t * const data = v;
        for(int n=0; n < count; n+=16) {
                int i;
                printf("%08llx: ", (offset + n) / stride);
                for(i=n; i < n+16; i++)
                        printf("%02x ", data[i]);
                printf("\t");
                for(i=n; i < n+16; i++) {
                        u_int c = (int)data[i];
                        if (c >= 0x20 && c < 0x7f)
                                printf("%c", c);
                        else
                                printf("%c", '.');
                }
                printf("\n");
        }
}
#endif