/*
 * Broadcom BCM63xx flash registration
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
 * Copyright (C) 2008 Florian Fainelli <florian@openwrt.org>
 * Copyright (C) 2012 Jonas Gorski <jonas.gorski@gmail.com>
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#include <linux/mtd/physmap.h>

#include <bcm63xx_cpu.h>
#include <bcm63xx_dev_flash.h>
#include <bcm63xx_regs.h>
#include <bcm63xx_io.h>

static struct mtd_partition mtd_partitions[] = {
        {
                .name           = "cfe",
                .offset         = 0x0,
                .size           = 0x40000,
        }
};

static const char *bcm63xx_part_types[] = { "bcm63xxpart", NULL };

static struct physmap_flash_data flash_data = {
        .width                  = 2,
        .parts                  = mtd_partitions,
        .part_probe_types       = bcm63xx_part_types,
};

static struct resource mtd_resources[] = {
        {
                .start          = 0,    /* filled at runtime */
                .end            = 0,    /* filled at runtime */
                .flags          = IORESOURCE_MEM,
        }
};

static struct platform_device mtd_dev = {
        .name                   = "physmap-flash",
        .resource               = mtd_resources,
        .num_resources          = ARRAY_SIZE(mtd_resources),
        .dev                    = {
                .platform_data  = &flash_data,
        },
};

static int __init bcm63xx_detect_flash_type(void)
{
        u32 val;

        switch (bcm63xx_get_cpu_id()) {
        case BCM6328_CPU_ID:
                val = bcm_misc_readl(MISC_STRAPBUS_6328_REG);
                if (val & STRAPBUS_6328_BOOT_SEL_SERIAL)
                        return BCM63XX_FLASH_TYPE_SERIAL;
                else
                        return BCM63XX_FLASH_TYPE_NAND;
        case BCM6338_CPU_ID:
        case BCM6345_CPU_ID:
        case BCM6348_CPU_ID:
                /* no way to auto detect so assume parallel */
                return BCM63XX_FLASH_TYPE_PARALLEL;
        case BCM3368_CPU_ID:
        case BCM6358_CPU_ID:
                val = bcm_gpio_readl(GPIO_STRAPBUS_REG);
                if (val & STRAPBUS_6358_BOOT_SEL_PARALLEL)
                        return BCM63XX_FLASH_TYPE_PARALLEL;
                else
                        return BCM63XX_FLASH_TYPE_SERIAL;
        case BCM6362_CPU_ID:
                val = bcm_misc_readl(MISC_STRAPBUS_6362_REG);
                if (val & STRAPBUS_6362_BOOT_SEL_SERIAL)
                        return BCM63XX_FLASH_TYPE_SERIAL;
                else
                        return BCM63XX_FLASH_TYPE_NAND;
        case BCM6368_CPU_ID:
                val = bcm_gpio_readl(GPIO_STRAPBUS_REG);
                switch (val & STRAPBUS_6368_BOOT_SEL_MASK) {
                case STRAPBUS_6368_BOOT_SEL_NAND:
                        return BCM63XX_FLASH_TYPE_NAND;
                case STRAPBUS_6368_BOOT_SEL_SERIAL:
                        return BCM63XX_FLASH_TYPE_SERIAL;
                case STRAPBUS_6368_BOOT_SEL_PARALLEL:
                        return BCM63XX_FLASH_TYPE_PARALLEL;
                }
                fallthrough;
        default:
                return -EINVAL;
        }
}

int __init bcm63xx_flash_register(void)
{
        int flash_type;
        u32 val;

        flash_type = bcm63xx_detect_flash_type();

        switch (flash_type) {
        case BCM63XX_FLASH_TYPE_PARALLEL:
                /* read base address of boot chip select (0) */
                val = bcm_mpi_readl(MPI_CSBASE_REG(0));
                val &= MPI_CSBASE_BASE_MASK;

                mtd_resources[0].start = val;
                mtd_resources[0].end = 0x1FFFFFFF;

                return platform_device_register(&mtd_dev);
        case BCM63XX_FLASH_TYPE_SERIAL:
                pr_warn("unsupported serial flash detected\n");
                return -ENODEV;
        case BCM63XX_FLASH_TYPE_NAND:
                pr_warn("unsupported NAND flash detected\n");
                return -ENODEV;
        default:
                pr_err("flash detection failed for BCM%x: %d\n",
                       bcm63xx_get_cpu_id(), flash_type);
                return -ENODEV;
        }
}