// SPDX-License-Identifier: GPL-2.0-only
/*
 *  linux/drivers/mtd/maps/pci.c
 *
 *  Copyright (C) 2001 Russell King, All rights reserved.
 *
 * Generic PCI memory map driver.  We support the following boards:
 *  - Intel IQ80310 ATU.
 *  - Intel EBSA285 (blank rom programming mode). Tested working 27/09/2001
 */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/slab.h>

#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#include <linux/mtd/partitions.h>

struct map_pci_info;

struct mtd_pci_info {
        int  (*init)(struct pci_dev *dev, struct map_pci_info *map);
        void (*exit)(struct pci_dev *dev, struct map_pci_info *map);
        unsigned long (*translate)(struct map_pci_info *map, unsigned long ofs);
        const char *map_name;
};

struct map_pci_info {
        struct map_info map;
        void __iomem *base;
        void (*exit)(struct pci_dev *dev, struct map_pci_info *map);
        unsigned long (*translate)(struct map_pci_info *map, unsigned long ofs);
        struct pci_dev *dev;
};

static map_word mtd_pci_read8(struct map_info *_map, unsigned long ofs)
{
        struct map_pci_info *map = (struct map_pci_info *)_map;
        map_word val;
        val.x[0]= readb(map->base + map->translate(map, ofs));
        return val;
}

static map_word mtd_pci_read32(struct map_info *_map, unsigned long ofs)
{
        struct map_pci_info *map = (struct map_pci_info *)_map;
        map_word val;
        val.x[0] = readl(map->base + map->translate(map, ofs));
        return val;
}

static void mtd_pci_copyfrom(struct map_info *_map, void *to, unsigned long from, ssize_t len)
{
        struct map_pci_info *map = (struct map_pci_info *)_map;
        memcpy_fromio(to, map->base + map->translate(map, from), len);
}

static void mtd_pci_write8(struct map_info *_map, map_word val, unsigned long ofs)
{
        struct map_pci_info *map = (struct map_pci_info *)_map;
        writeb(val.x[0], map->base + map->translate(map, ofs));
}

static void mtd_pci_write32(struct map_info *_map, map_word val, unsigned long ofs)
{
        struct map_pci_info *map = (struct map_pci_info *)_map;
        writel(val.x[0], map->base + map->translate(map, ofs));
}

static void mtd_pci_copyto(struct map_info *_map, unsigned long to, const void *from, ssize_t len)
{
        struct map_pci_info *map = (struct map_pci_info *)_map;
        memcpy_toio(map->base + map->translate(map, to), from, len);
}

static const struct map_info mtd_pci_map = {
        .phys =         NO_XIP,
        .copy_from =    mtd_pci_copyfrom,
        .copy_to =      mtd_pci_copyto,
};

/*
 * Intel IOP80310 Flash driver
 */

static int
intel_iq80310_init(struct pci_dev *dev, struct map_pci_info *map)
{
        u32 win_base;

        map->map.bankwidth = 1;
        map->map.read = mtd_pci_read8;
        map->map.write = mtd_pci_write8;

        map->map.size     = 0x00800000;
        map->base         = ioremap(pci_resource_start(dev, 0),
                                            pci_resource_len(dev, 0));

        if (!map->base)
                return -ENOMEM;

        /*
         * We want to base the memory window at Xscale
         * bus address 0, not 0x1000.
         */
        pci_read_config_dword(dev, 0x44, &win_base);
        pci_write_config_dword(dev, 0x44, 0);

        map->map.map_priv_2 = win_base;

        return 0;
}

static void
intel_iq80310_exit(struct pci_dev *dev, struct map_pci_info *map)
{
        if (map->base)
                iounmap(map->base);
        pci_write_config_dword(dev, 0x44, map->map.map_priv_2);
}

static unsigned long
intel_iq80310_translate(struct map_pci_info *map, unsigned long ofs)
{
        unsigned long page_addr = ofs & 0x00400000;

        /*
         * This mundges the flash location so we avoid
         * the first 80 bytes (they appear to read nonsense).
         */
        if (page_addr) {
                writel(0x00000008, map->base + 0x1558);
                writel(0x00000000, map->base + 0x1550);
        } else {
                writel(0x00000007, map->base + 0x1558);
                writel(0x00800000, map->base + 0x1550);
                ofs += 0x00800000;
        }

        return ofs;
}

static struct mtd_pci_info intel_iq80310_info = {
        .init =         intel_iq80310_init,
        .exit =         intel_iq80310_exit,
        .translate =    intel_iq80310_translate,
        .map_name =     "cfi_probe",
};

/*
 * Intel DC21285 driver
 */

static int
intel_dc21285_init(struct pci_dev *dev, struct map_pci_info *map)
{
        unsigned long base, len;

        base = pci_resource_start(dev, PCI_ROM_RESOURCE);
        len  = pci_resource_len(dev, PCI_ROM_RESOURCE);

        if (!len || !base) {
                /*
                 * No ROM resource
                 */
                base = pci_resource_start(dev, 2);
                len  = pci_resource_len(dev, 2);

                /*
                 * We need to re-allocate PCI BAR2 address range to the
                 * PCI ROM BAR, and disable PCI BAR2.
                 */
        } else {
                /*
                 * Hmm, if an address was allocated to the ROM resource, but
                 * not enabled, should we be allocating a new resource for it
                 * or simply enabling it?
                 */
                pci_enable_rom(dev);
                printk("%s: enabling expansion ROM\n", pci_name(dev));
        }

        if (!len || !base)
                return -ENXIO;

        map->map.bankwidth = 4;
        map->map.read = mtd_pci_read32;
        map->map.write = mtd_pci_write32;
        map->map.size     = len;
        map->base         = ioremap(base, len);

        if (!map->base)
                return -ENOMEM;

        return 0;
}

static void
intel_dc21285_exit(struct pci_dev *dev, struct map_pci_info *map)
{
        if (map->base)
                iounmap(map->base);

        /*
         * We need to undo the PCI BAR2/PCI ROM BAR address alteration.
         */
        pci_disable_rom(dev);
}

static unsigned long
intel_dc21285_translate(struct map_pci_info *map, unsigned long ofs)
{
        return ofs & 0x00ffffc0 ? ofs : (ofs ^ (1 << 5));
}

static struct mtd_pci_info intel_dc21285_info = {
        .init =         intel_dc21285_init,
        .exit =         intel_dc21285_exit,
        .translate =    intel_dc21285_translate,
        .map_name =     "jedec_probe",
};

/*
 * PCI device ID table
 */

static const struct pci_device_id mtd_pci_ids[] = {
        {
                .vendor =       PCI_VENDOR_ID_INTEL,
                .device =       0x530d,
                .subvendor =    PCI_ANY_ID,
                .subdevice =    PCI_ANY_ID,
                .class =        PCI_CLASS_MEMORY_OTHER << 8,
                .class_mask =   0xffff00,
                .driver_data =  (unsigned long)&intel_iq80310_info,
        },
        {
                .vendor =       PCI_VENDOR_ID_DEC,
                .device =       PCI_DEVICE_ID_DEC_21285,
                .subvendor =    0,      /* DC21285 defaults to 0 on reset */
                .subdevice =    0,      /* DC21285 defaults to 0 on reset */
                .driver_data =  (unsigned long)&intel_dc21285_info,
        },
        { 0, }
};

/*
 * Generic code follows.
 */

static int mtd_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
{
        struct mtd_pci_info *info = (struct mtd_pci_info *)id->driver_data;
        struct map_pci_info *map = NULL;
        struct mtd_info *mtd = NULL;
        int err;

        err = pci_enable_device(dev);
        if (err)
                goto out;

        err = pci_request_regions(dev, "pci mtd");
        if (err)
                goto out;

        map = kmalloc(sizeof(*map), GFP_KERNEL);
        err = -ENOMEM;
        if (!map)
                goto release;

        map->map       = mtd_pci_map;
        map->map.name  = pci_name(dev);
        map->dev       = dev;
        map->exit      = info->exit;
        map->translate = info->translate;

        err = info->init(dev, map);
        if (err)
                goto release;

        mtd = do_map_probe(info->map_name, &map->map);
        err = -ENODEV;
        if (!mtd)
                goto release;

        mtd->owner = THIS_MODULE;
        mtd_device_register(mtd, NULL, 0);

        pci_set_drvdata(dev, mtd);

        return 0;

release:
        if (map) {
                map->exit(dev, map);
                kfree(map);
        }

        pci_release_regions(dev);
out:
        return err;
}

static void mtd_pci_remove(struct pci_dev *dev)
{
        struct mtd_info *mtd = pci_get_drvdata(dev);
        struct map_pci_info *map = mtd->priv;

        mtd_device_unregister(mtd);
        map_destroy(mtd);
        map->exit(dev, map);
        kfree(map);

        pci_release_regions(dev);
}

static struct pci_driver mtd_pci_driver = {
        .name =         "MTD PCI",
        .probe =        mtd_pci_probe,
        .remove =       mtd_pci_remove,
        .id_table =     mtd_pci_ids,
};

module_pci_driver(mtd_pci_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
MODULE_DESCRIPTION("Generic PCI map driver");
MODULE_DEVICE_TABLE(pci, mtd_pci_ids);