// SPDX-License-Identifier: GPL-2.0-only

/*

 * Copyright (c) 2011 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix

 */

#include <common.h>

#include <driver.h>

#include <init.h>

#include <asm/cache.h>

static int mem_flush(struct cdev *cdev)

{

  sync_caches_for_execution();

  return 0;

}

static struct cdev_operations memops = {

  .read  = mem_read,

  .write = mem_write,

  .memmap = generic_memmap_rw,

  .flush = mem_flush,

};

static int mem_probe(struct device *dev)

{

  struct cdev *cdev;

  cdev = xzalloc(sizeof (*cdev));

  dev->priv = cdev;

  cdev->name = (char*)dev->resource[0].name;

  if (dev->resource[0].start == 0 && dev->resource[0].end == ~0) {

    /*

     * Special case for /dev/mem. We can't express it's size as it's

     * outside of our address range. Set DEVFS_IS_CHARACTER_DEV to

     * bypass size checks.

     */

    cdev->size = 0;

    cdev->flags = DEVFS_IS_CHARACTER_DEV;

  } else {

    cdev->size = resource_size(&dev->resource[0]);

  }

  cdev->ops = &memops;

  cdev->dev = dev;

  devfs_create(cdev);

  return 0;

}

static struct driver mem_drv = {

  .name  = "mem",

  .probe = mem_probe,

};

static int mem_init(void)

{

  struct device *dev;

  struct resource res = {

    .start = 0,

    .end = ~0,

    .flags = IORESOURCE_MEM,

    .name = "mem",

  };

  int ret;

  dev = device_alloc("mem", DEVICE_ID_DYNAMIC);

  if (!dev)

    return -ENOMEM;

  dev->resource = xmemdup(&res, sizeof(res));

  dev->num_resources = 1;

  ret = platform_device_register(dev);

  if (ret)

    return ret;

  return platform_driver_register(&mem_drv);

}

device_initcall(mem_init);