kernel-ark/drivers/char/ps3flash.c

441 lines
11 KiB
C
Raw Normal View History

/*
* PS3 FLASH ROM Storage Driver
*
* Copyright (C) 2007 Sony Computer Entertainment Inc.
* Copyright 2007 Sony Corp.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published
* by the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <linux/fs.h>
#include <linux/miscdevice.h>
#include <linux/uaccess.h>
#include <asm/lv1call.h>
#include <asm/ps3stor.h>
#define DEVICE_NAME "ps3flash"
#define FLASH_BLOCK_SIZE (256*1024)
struct ps3flash_private {
struct mutex mutex; /* Bounce buffer mutex */
};
static struct ps3_storage_device *ps3flash_dev;
static ssize_t ps3flash_read_write_sectors(struct ps3_storage_device *dev,
u64 lpar, u64 start_sector,
u64 sectors, int write)
{
u64 res = ps3stor_read_write_sectors(dev, lpar, start_sector, sectors,
write);
if (res) {
dev_err(&dev->sbd.core, "%s:%u: %s failed 0x%lx\n", __func__,
__LINE__, write ? "write" : "read", res);
return -EIO;
}
return sectors;
}
static ssize_t ps3flash_read_sectors(struct ps3_storage_device *dev,
u64 start_sector, u64 sectors,
unsigned int sector_offset)
{
u64 max_sectors, lpar;
max_sectors = dev->bounce_size / dev->blk_size;
if (sectors > max_sectors) {
dev_dbg(&dev->sbd.core, "%s:%u Limiting sectors to %lu\n",
__func__, __LINE__, max_sectors);
sectors = max_sectors;
}
lpar = dev->bounce_lpar + sector_offset * dev->blk_size;
return ps3flash_read_write_sectors(dev, lpar, start_sector, sectors,
0);
}
static ssize_t ps3flash_write_chunk(struct ps3_storage_device *dev,
u64 start_sector)
{
u64 sectors = dev->bounce_size / dev->blk_size;
return ps3flash_read_write_sectors(dev, dev->bounce_lpar, start_sector,
sectors, 1);
}
static loff_t ps3flash_llseek(struct file *file, loff_t offset, int origin)
{
struct ps3_storage_device *dev = ps3flash_dev;
loff_t res;
mutex_lock(&file->f_mapping->host->i_mutex);
switch (origin) {
case 1:
offset += file->f_pos;
break;
case 2:
offset += dev->regions[dev->region_idx].size*dev->blk_size;
break;
}
if (offset < 0) {
res = -EINVAL;
goto out;
}
file->f_pos = offset;
res = file->f_pos;
out:
mutex_unlock(&file->f_mapping->host->i_mutex);
return res;
}
static ssize_t ps3flash_read(struct file *file, char __user *buf, size_t count,
loff_t *pos)
{
struct ps3_storage_device *dev = ps3flash_dev;
struct ps3flash_private *priv = dev->sbd.core.driver_data;
u64 size, start_sector, end_sector, offset;
ssize_t sectors_read;
size_t remaining, n;
dev_dbg(&dev->sbd.core,
"%s:%u: Reading %zu bytes at position %lld to user 0x%p\n",
__func__, __LINE__, count, *pos, buf);
size = dev->regions[dev->region_idx].size*dev->blk_size;
if (*pos >= size || !count)
return 0;
if (*pos + count > size) {
dev_dbg(&dev->sbd.core,
"%s:%u Truncating count from %zu to %llu\n", __func__,
__LINE__, count, size - *pos);
count = size - *pos;
}
start_sector = *pos / dev->blk_size;
offset = *pos % dev->blk_size;
end_sector = DIV_ROUND_UP(*pos + count, dev->blk_size);
remaining = count;
do {
mutex_lock(&priv->mutex);
sectors_read = ps3flash_read_sectors(dev, start_sector,
end_sector-start_sector,
0);
if (sectors_read < 0) {
mutex_unlock(&priv->mutex);
goto fail;
}
n = min(remaining, sectors_read*dev->blk_size-offset);
dev_dbg(&dev->sbd.core,
"%s:%u: copy %lu bytes from 0x%p to user 0x%p\n",
__func__, __LINE__, n, dev->bounce_buf+offset, buf);
if (copy_to_user(buf, dev->bounce_buf+offset, n)) {
mutex_unlock(&priv->mutex);
sectors_read = -EFAULT;
goto fail;
}
mutex_unlock(&priv->mutex);
*pos += n;
buf += n;
remaining -= n;
start_sector += sectors_read;
offset = 0;
} while (remaining > 0);
return count;
fail:
return sectors_read;
}
static ssize_t ps3flash_write(struct file *file, const char __user *buf,
size_t count, loff_t *pos)
{
struct ps3_storage_device *dev = ps3flash_dev;
struct ps3flash_private *priv = dev->sbd.core.driver_data;
u64 size, chunk_sectors, start_write_sector, end_write_sector,
end_read_sector, start_read_sector, head, tail, offset;
ssize_t res;
size_t remaining, n;
unsigned int sec_off;
dev_dbg(&dev->sbd.core,
"%s:%u: Writing %zu bytes at position %lld from user 0x%p\n",
__func__, __LINE__, count, *pos, buf);
size = dev->regions[dev->region_idx].size*dev->blk_size;
if (*pos >= size || !count)
return 0;
if (*pos + count > size) {
dev_dbg(&dev->sbd.core,
"%s:%u Truncating count from %zu to %llu\n", __func__,
__LINE__, count, size - *pos);
count = size - *pos;
}
chunk_sectors = dev->bounce_size / dev->blk_size;
start_write_sector = *pos / dev->bounce_size * chunk_sectors;
offset = *pos % dev->bounce_size;
end_write_sector = DIV_ROUND_UP(*pos + count, dev->bounce_size) *
chunk_sectors;
end_read_sector = DIV_ROUND_UP(*pos, dev->blk_size);
start_read_sector = (*pos + count) / dev->blk_size;
/*
* As we have to write in 256 KiB chunks, while we can read in blk_size
* (usually 512 bytes) chunks, we perform the following steps:
* 1. Read from start_write_sector to end_read_sector ("head")
* 2. Read from start_read_sector to end_write_sector ("tail")
* 3. Copy data to buffer
* 4. Write from start_write_sector to end_write_sector
* All of this is complicated by using only one 256 KiB bounce buffer.
*/
head = end_read_sector - start_write_sector;
tail = end_write_sector - start_read_sector;
remaining = count;
do {
mutex_lock(&priv->mutex);
if (end_read_sector >= start_read_sector) {
/* Merge head and tail */
dev_dbg(&dev->sbd.core,
"Merged head and tail: %lu sectors at %lu\n",
chunk_sectors, start_write_sector);
res = ps3flash_read_sectors(dev, start_write_sector,
chunk_sectors, 0);
if (res < 0)
goto fail;
} else {
if (head) {
/* Read head */
dev_dbg(&dev->sbd.core,
"head: %lu sectors at %lu\n", head,
start_write_sector);
res = ps3flash_read_sectors(dev,
start_write_sector,
head, 0);
if (res < 0)
goto fail;
}
if (start_read_sector <
start_write_sector+chunk_sectors) {
/* Read tail */
dev_dbg(&dev->sbd.core,
"tail: %lu sectors at %lu\n", tail,
start_read_sector);
sec_off = start_read_sector-start_write_sector;
res = ps3flash_read_sectors(dev,
start_read_sector,
tail, sec_off);
if (res < 0)
goto fail;
}
}
n = min(remaining, dev->bounce_size-offset);
dev_dbg(&dev->sbd.core,
"%s:%u: copy %lu bytes from user 0x%p to 0x%p\n",
__func__, __LINE__, n, buf, dev->bounce_buf+offset);
if (copy_from_user(dev->bounce_buf+offset, buf, n)) {
res = -EFAULT;
goto fail;
}
res = ps3flash_write_chunk(dev, start_write_sector);
if (res < 0)
goto fail;
mutex_unlock(&priv->mutex);
*pos += n;
buf += n;
remaining -= n;
start_write_sector += chunk_sectors;
head = 0;
offset = 0;
} while (remaining > 0);
return count;
fail:
mutex_unlock(&priv->mutex);
return res;
}
static irqreturn_t ps3flash_interrupt(int irq, void *data)
{
struct ps3_storage_device *dev = data;
int res;
u64 tag, status;
res = lv1_storage_get_async_status(dev->sbd.dev_id, &tag, &status);
if (tag != dev->tag)
dev_err(&dev->sbd.core,
"%s:%u: tag mismatch, got %lx, expected %lx\n",
__func__, __LINE__, tag, dev->tag);
if (res) {
dev_err(&dev->sbd.core, "%s:%u: res=%d status=0x%lx\n",
__func__, __LINE__, res, status);
} else {
dev->lv1_status = status;
complete(&dev->done);
}
return IRQ_HANDLED;
}
static const struct file_operations ps3flash_fops = {
.owner = THIS_MODULE,
.llseek = ps3flash_llseek,
.read = ps3flash_read,
.write = ps3flash_write,
};
static struct miscdevice ps3flash_misc = {
.minor = MISC_DYNAMIC_MINOR,
.name = DEVICE_NAME,
.fops = &ps3flash_fops,
};
static int __devinit ps3flash_probe(struct ps3_system_bus_device *_dev)
{
struct ps3_storage_device *dev = to_ps3_storage_device(&_dev->core);
struct ps3flash_private *priv;
int error;
unsigned long tmp;
tmp = dev->regions[dev->region_idx].start*dev->blk_size;
if (tmp % FLASH_BLOCK_SIZE) {
dev_err(&dev->sbd.core,
"%s:%u region start %lu is not aligned\n", __func__,
__LINE__, tmp);
return -EINVAL;
}
tmp = dev->regions[dev->region_idx].size*dev->blk_size;
if (tmp % FLASH_BLOCK_SIZE) {
dev_err(&dev->sbd.core,
"%s:%u region size %lu is not aligned\n", __func__,
__LINE__, tmp);
return -EINVAL;
}
/* use static buffer, kmalloc cannot allocate 256 KiB */
if (!ps3flash_bounce_buffer.address)
return -ENODEV;
if (ps3flash_dev) {
dev_err(&dev->sbd.core,
"Only one FLASH device is supported\n");
return -EBUSY;
}
ps3flash_dev = dev;
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (!priv) {
error = -ENOMEM;
goto fail;
}
dev->sbd.core.driver_data = priv;
mutex_init(&priv->mutex);
dev->bounce_size = ps3flash_bounce_buffer.size;
dev->bounce_buf = ps3flash_bounce_buffer.address;
error = ps3stor_setup(dev, ps3flash_interrupt);
if (error)
goto fail_free_priv;
ps3flash_misc.parent = &dev->sbd.core;
error = misc_register(&ps3flash_misc);
if (error) {
dev_err(&dev->sbd.core, "%s:%u: misc_register failed %d\n",
__func__, __LINE__, error);
goto fail_teardown;
}
dev_info(&dev->sbd.core, "%s:%u: registered misc device %d\n",
__func__, __LINE__, ps3flash_misc.minor);
return 0;
fail_teardown:
ps3stor_teardown(dev);
fail_free_priv:
kfree(priv);
dev->sbd.core.driver_data = NULL;
fail:
ps3flash_dev = NULL;
return error;
}
static int ps3flash_remove(struct ps3_system_bus_device *_dev)
{
struct ps3_storage_device *dev = to_ps3_storage_device(&_dev->core);
misc_deregister(&ps3flash_misc);
ps3stor_teardown(dev);
kfree(dev->sbd.core.driver_data);
dev->sbd.core.driver_data = NULL;
ps3flash_dev = NULL;
return 0;
}
static struct ps3_system_bus_driver ps3flash = {
.match_id = PS3_MATCH_ID_STOR_FLASH,
.core.name = DEVICE_NAME,
.core.owner = THIS_MODULE,
.probe = ps3flash_probe,
.remove = ps3flash_remove,
.shutdown = ps3flash_remove,
};
static int __init ps3flash_init(void)
{
return ps3_system_bus_driver_register(&ps3flash);
}
static void __exit ps3flash_exit(void)
{
ps3_system_bus_driver_unregister(&ps3flash);
}
module_init(ps3flash_init);
module_exit(ps3flash_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("PS3 FLASH ROM Storage Driver");
MODULE_AUTHOR("Sony Corporation");
MODULE_ALIAS(PS3_MODULE_ALIAS_STOR_FLASH);