platform/armemu/blkdev.c

/*
 * Copyright (c) 2010 Travis Geiselbrecht
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files
 * (the "Software"), to deal in the Software without restriction,
 * including without limitation the rights to use, copy, modify, merge,
 * publish, distribute, sublicense, and/or sell copies of the Software,
 * and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
#include <err.h>
#include <debug.h>
#include <platform.h>
#include "platform_p.h"
#include <platform/armemu.h>
#include <lib/bio.h>
#include <reg.h>

static bdev_t dev;

static uint64_t get_blkdev_len(void)
{
	return *REG64(BDEV_LEN);
}

ssize_t read_block(struct bdev *dev, void *buf, bnum_t block, uint count)
{
	/* assume args have been validated by layer above */
	*REG32(BDEV_CMD_ADDR) = (uint32_t)buf;
	*REG64(BDEV_CMD_OFF) = (uint64_t)((uint64_t)block * dev->block_size);
	*REG32(BDEV_CMD_LEN) = count * dev->block_size;

	*REG32(BDEV_CMD) = BDEV_CMD_READ;

	uint32_t err = *REG32(BDEV_CMD) & BDEV_CMD_ERRMASK;
	if (err == BDEV_CMD_ERR_NONE)
		return count * dev->block_size;
	else
		return ERR_IO;
}

ssize_t write_block(struct bdev *dev, const void *buf, bnum_t block, uint count)
{
	/* assume args have been validated by layer above */
	*REG32(BDEV_CMD_ADDR) = (uint32_t)buf;
	*REG64(BDEV_CMD_OFF) = (uint64_t)((uint64_t)block * dev->block_size);
	*REG32(BDEV_CMD_LEN) = count * dev->block_size;

	*REG32(BDEV_CMD) = BDEV_CMD_WRITE;

	uint32_t err = *REG32(BDEV_CMD) & BDEV_CMD_ERRMASK;
	if (err == BDEV_CMD_ERR_NONE)
		return count * dev->block_size;
	else
		return ERR_IO;
}

void platform_init_blkdev(void)
{
	if ((*REG32(SYSINFO_FEATURES) & SYSINFO_FEATURE_BLOCKDEV) == 0)
		return; // no block device

	TRACEF("device len %lld\n", get_blkdev_len());

	if (get_blkdev_len() == 0)
		return;

	bio_initialize_bdev(&dev, "block0", 512, get_blkdev_len() / 512);

	// fill in hooks
	dev.read_block = &read_block;
	dev.write_block = &write_block;

	bio_register_device(&dev);
}