- 根目录:
- drivers
- mtd
- lpddr
- lpddr_cmds.c
/*
* LPDDR flash memory device operations. This module provides read, write,
* erase, lock/unlock support for LPDDR flash memories
* (C) 2008 Korolev Alexey <akorolev@infradead.org>
* (C) 2008 Vasiliy Leonenko <vasiliy.leonenko@gmail.com>
* Many thanks to Roman Borisov for initial enabling
*
* 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; either version 2
* of the License, or (at your option) any later version.
*
* 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.
* TODO:
* Implement VPP management
* Implement XIP support
* Implement OTP support
*/
#include <linux/mtd/pfow.h>
#include <linux/mtd/qinfo.h>
#include <linux/slab.h>
#include <linux/module.h>
static int lpddr_read(struct mtd_info *mtd, loff_t adr, size_t len,
size_t *retlen, u_char *buf);
static int lpddr_write_buffers(struct mtd_info *mtd, loff_t to,
size_t len, size_t *retlen, const u_char *buf);
static int lpddr_writev(struct mtd_info *mtd, const struct kvec *vecs,
unsigned long count, loff_t to, size_t *retlen);
static int lpddr_erase(struct mtd_info *mtd, struct erase_info *instr);
static int lpddr_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
static int lpddr_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
static int lpddr_point(struct mtd_info *mtd, loff_t adr, size_t len,
size_t *retlen, void **mtdbuf, resource_size_t *phys);
static int lpddr_unpoint(struct mtd_info *mtd, loff_t adr, size_t len);
static int get_chip(struct map_info *map, struct flchip *chip, int mode);
static int chip_ready(struct map_info *map, struct flchip *chip, int mode);
static void put_chip(struct map_info *map, struct flchip *chip);
struct mtd_info *lpddr_cmdset(struct map_info *map)
{
struct lpddr_private *lpddr = map->fldrv_priv;
struct flchip_shared *shared;
struct flchip *chip;
struct mtd_info *mtd;
int numchips;
int i, j;
mtd = kzalloc(sizeof(*mtd), GFP_KERNEL);
if (!mtd)
return NULL;
mtd->priv = map;
mtd->type = MTD_NORFLASH;
/* Fill in the default mtd operations */
mtd->_read = lpddr_read;
mtd->type = MTD_NORFLASH;
mtd->flags = MTD_CAP_NORFLASH;
mtd->flags &= ~MTD_BIT_WRITEABLE;
mtd->_erase = lpddr_erase;
mtd->_write = lpddr_write_buffers;
mtd->_writev = lpddr_writev;
mtd->_lock = lpddr_lock;
mtd->_unlock = lpddr_unlock;
if (map_is_linear(map)) {
mtd->_point = lpddr_point;
mtd->_unpoint = lpddr_unpoint;
}
mtd->size = 1 << lpddr->qinfo->DevSizeShift;
mtd->erasesize = 1 << lpddr->qinfo->UniformBlockSizeShift;
mtd->writesize = 1 << lpddr->qinfo->BufSizeShift;
shared = kmalloc(sizeof(struct flchip_shared) * lpddr->numchips,
GFP_KERNEL);
if (!shared) {
kfree(lpddr);
kfree(mtd);
return NULL;
}
chip = &lpddr->chips[0];
numchips = lpddr->numchips / lpddr->qinfo->HWPartsNum;
for (i = 0; i < numchips; i++) {
shared[i].writing = shared[i].erasing = NULL;
mutex_init(&shared[i].lock);
for (j = 0; j < lpddr->qinfo->HWPartsNum; j++) {
*chip = lpddr->chips[i];
chip->start += j << lpddr->chipshift;
chip->oldstate = chip->state = FL_READY;
chip->priv = &shared[i];
/* those should be reset too since
they create memory references. */
init_waitqueue_head(&chip->wq);
mutex_init(&chip->mutex);
chip++;
}
}
return mtd;
}
EXPORT_SYMBOL(lpddr_cmdset);
static int wait_for_ready(struct map_info *map, struct flchip *chip,
unsigned int chip_op_time)
{
unsigned int timeo, reset_timeo, sleep_time;
unsigned int dsr;
flstate_t chip_state = chip->state;
int ret = 0;
/* set our timeout to 8 times the expected delay */
timeo = chip_op_time * 8;
if (!timeo)
timeo = 500000;
reset_timeo = timeo;
sleep_time = chip_op_time / 2;
for (;;) {
dsr = CMDVAL(map_read(map, map->pfow_base + PFOW_DSR));
if (dsr & DSR_READY_STATUS)
break;
if (!timeo) {
printk(KERN_ERR "%s: Flash timeout error state %d \n",
map->name, chip_state);
ret = -ETIME;
break;
}
/* OK Still waiting. Drop the lock, wait a while and retry. */
mutex_unlock(&chip->mutex);
if (sleep_time >= 1000000/HZ) {
/*
* Half of the normal delay still remaining
* can be performed with a sleeping delay instead
* of busy waiting.
*/
msleep(sleep_time/1000);
timeo -= sleep_time;
sleep_time = 1000000/HZ;
} else {
udelay(1);
cond_resched();
timeo--;
}
mutex_lock(&chip->mutex);
while (chip->state != chip_state) {
/* Someone's suspended the operation: sleep */
DECLARE_WAITQUEUE(wait, current);
set_current_state(TASK_UNINTERRUPTIBLE);
add_wait_queue(&chip->wq, &wait);
mutex_unlock(&chip->mutex);
schedule();
remove_wait_queue(&chip->wq, &wait);
mutex_lock(&chip->mutex);
}
if (chip->erase_suspended || chip->write_suspended) {
/* Suspend has occurred while sleep: reset timeout */
timeo = reset_timeo;
chip->erase_suspended = chip->write_suspended = 0;
}
}
/* check status for errors */
if (dsr & DSR_ERR) {
/* Clear DSR*/
map_write(map, CMD(~(DSR_ERR)), map->pfow_base + PFOW_DSR);
printk(KERN_WARNING"%s: Bad status on wait: 0x%x \n",
map->name, dsr);
print_drs_error(dsr);
ret = -EIO;
}
chip->state = FL_READY;
return ret;
}
static int get_chip(struct map_info *map, struct flchip *chip, int mode)
{
int ret;
DECLARE_WAITQUEUE(wait, current);
retry:
if (chip->priv && (mode == FL_WRITING || mode == FL_ERASING)
&& chip->state != FL_SYNCING) {
/*
* OK. We have possibility for contension on the write/erase
* operations which are global to the real chip and not per
* partition. So let's fight it over in the partition which
* currently has authority on the operation.
*
* The rules are as follows:
*
* - any write operation must own shared->writing.
*
* - any erase operation must own _both_ shared->writing and
* shared->erasing.
*
* - contension arbitration is handled in the owner's context.
*
* The 'shared' struct can be read and/or written only when
* its lock is taken.
*/
struct flchip_shared *shared = chip->priv;
struct flchip *contender;
mutex_lock(&shared->lock);
contender = shared->writing;
if (contender && contender != chip) {
/*
* The engine to perform desired operation on this
* partition is already in use by someone else.
* Let's fight over it in the context of the chip
* currently using it. If it is possible to suspend,
* that other partition will do just that, otherwise
* it'll happily send us to sleep. In any case, when
* get_chip returns success we're clear to go ahead.
*/
ret = mutex_trylock(&contender->mutex);
mutex_unlock(&shared->lock);
if (!ret)
goto retry;
mutex_unlock(&chip->mutex);
ret = chip_ready(map, contender, mode);
mutex_lock(&chip->mutex);
if (ret == -EAGAIN) {
mutex_unlock(&contender->mutex);
goto retry;
}
if (ret) {
mutex_unlock(&contender->mutex);
return ret;
}
mutex_lock(&shared->lock);
/* We should not own chip if it is already in FL_SYNCING
* state. Put contender and retry. */
if (chip->state == FL_SYNCING) {
put_chip(map, contender);
mutex_unlock(&contender->mutex);
goto retry;
}
mutex_unlock(&contender->mutex);
}
/* Check if we have suspended erase on this chip.
Must sleep in such a case. */
if (mode == FL_ERASING && shared->erasing
&& shared->erasing->oldstate == FL_ERASING) {
mutex_unlock(&shared->lock);
set_current_state(TASK_UNINTERRUPTIBLE);
add_wait_queue(&chip->wq, &wait);
mutex_unlock(&chip->mutex);
schedule();
remove_wait_queue(&chip->wq, &wait);
mutex_lock(&chip->mutex);
goto retry;
}
/* We now own it */
shared->writing = chip;
if (mode == FL_ERASING)
shared->erasing = chip;
mutex_unlock(&shared->lock);
}
ret = chip_ready(map, chip, mode);
if (ret == -EAGAIN)
goto retry;
return ret;
}
static int chip_ready(struct map_info *map, struct flchip *chip, int mode)
{
struct lpddr_private *lpddr = map->fldrv_priv;
int ret = 0;
DECLARE_WAITQUEUE(wait, current);
/* Prevent setting state FL_SYNCING for chip in suspended state. */
if (FL_SYNCING == mode && FL_READY != chip->oldstate)
goto sleep;
switch (chip->state) {
case FL_READY:
case FL_JEDEC_QUERY:
return 0;
case FL_ERASING:
if (!lpddr->qinfo->SuspEraseSupp ||
!(mode == FL_READY || mode == FL_POINT))
goto sleep;
map_write(map, CMD(LPDDR_SUSPEND),
map->pfow_base + PFOW_PROGRAM_ERASE_SUSPEND);
chip->oldstate = FL_ERASING;
chip->state = FL_ERASE_SUSPENDING;
ret = wait_for_ready(map, chip, 0);
if (ret) {
/* Oops. something got wrong. */
/* Resume and pretend we weren't here. */
put_chip(map, chip);
printk(KERN_ERR "%s: suspend operation failed."
"State may be wrong \n", map->name);
return -EIO;
}
chip->erase_suspended = 1;
chip->state = FL_READY;
return 0;
/* Erase suspend */
case FL_POINT:
/* Only if there's no operation suspended... */
if (mode == FL_READY && chip->oldstate == FL_READY)
return 0;
default:
sleep:
set_current_state(TASK_UNINTERRUPTIBLE);
add_wait_queue(&chip->wq, &wait);
mutex_unlock(&chip->mutex);
schedule();
remove_wait_queue(&chip->wq, &wait);
mutex_lock(&chip->mutex);
return -EAGAIN;
}
}
static void put_chip(struct map_info *map, struct flchip *chip)
{
if (chip->priv) {
struct flchip_shared *shared = chip->priv;
mutex_lock(&shared->lock);
if (shared->writing == chip && chip->oldstate == FL_READY) {
/* We own the ability to write, but we're done */
shared->writing = shared->erasing;
if (shared->writing && shared->writing != chip) {
/* give back the ownership */
struct flchip *loaner = shared->writing;
mutex_lock(&loaner->mutex);
mutex_unlock(&shared->lock);
mutex_unlock(&chip->mutex);
put_chip(map, loaner);
mutex_lock(&chip->mutex);
mutex_unlock(&loaner->mutex);
wake_up(&chip->wq);
return;
}
shared->erasing = NULL;
shared->writing = NULL;
} else if (shared->erasing == chip && shared->writing != chip) {
/*
* We own the ability to erase without the ability
* to write, which means the erase was suspended
* and some other partition is currently writing.
* Don't let the switch below mess things up since
* we don't have ownership to resume anything.
*/
mutex_unlock(&shared->lock);
wake_up(&chip->wq);
return;
}
mutex_unlock(&shared->lock);
}
switch (chip->oldstate) {
case FL_ERASING:
map_write(map, CMD(LPDDR_RESUME),
map->pfow_base + PFOW_COMMAND_CODE);
map_write(map, CMD(LPDDR_START_EXECUTION),
map->pfow_base + PFOW_COMMAND_EXECUTE);
chip->oldstate = FL_READY;
chip->state = FL_ERASING;
break;
case FL_READY:
break;
default:
printk(KERN_ERR "%s: put_chip() called with oldstate %d!\n",
map->name, chip->oldstate);
}
wake_up(&chip->wq);
}
static int do_write_buffer(struct map_info *map, struct flchip *chip,
unsigned long adr, const struct kvec **pvec,
unsigned long *pvec_seek, int len)
{
struct lpddr_private *lpddr = map->fldrv_priv;
map_word datum;
int ret, wbufsize, word_gap, words;
const struct kvec *vec;
unsigned long vec_seek;
unsigned long prog_buf_ofs;
wbufsize = 1 << lpddr->qinfo->BufSizeShift;
mutex_lock(&chip->mutex);
ret = get_chip(map, chip, FL_WRITING);
if (ret) {
mutex_unlock(&chip->mutex);
return ret;
}
/* Figure out the number of words to write */
word_gap = (-adr & (map_bankwidth(map)-1));
words = (len - word_gap + map_bankwidth(map) - 1) / map_bankwidth(map);
if (!word_gap) {
words--;
} else {
word_gap = map_bankwidth(map) - word_gap;
adr -= word_gap;
datum = map_word_ff(map);
}
/* Write data */
/* Get the program buffer offset from PFOW register data first*/
prog_buf_ofs = map->pfow_base + CMDVAL(map_read(map,
map->pfow_base + PFOW_PROGRAM_BUFFER_OFFSET));
vec = *pvec;
vec_seek = *pvec_seek;
do {
int n = map_bankwidth(map) - word_gap;
if (n > vec->iov_len - vec_seek)
n = vec->iov_len - vec_seek;
if (n > len)
n = len;
if (!word_gap && (len < map_bankwidth(map)))
datum = map_word_ff(map);
datum = map_word_load_partial(map, datum,
vec->iov_base + vec_seek, word_gap, n);
len -= n;
word_gap += n;
if (!len || word_gap == map_bankwidth(map)) {
map_write(map, datum, prog_buf_ofs);
prog_buf_ofs += map_bankwidth(map);
word_gap = 0;
}
vec_seek += n;
if (vec_seek == vec->iov_len) {
vec++;
vec_seek = 0;
}
} while (len);
*pvec = vec;
*pvec_seek = vec_seek;
/* GO GO GO */
send_pfow_command(map, LPDDR_BUFF_PROGRAM, adr, wbufsize, NULL);
chip->state = FL_WRITING;
ret = wait_for_ready(map, chip, (1<<lpddr->qinfo->ProgBufferTime));
if (ret) {
printk(KERN_WARNING"%s Buffer program error: %d at %lx; \n",
map->name, ret, adr);
goto out;
}
out: put_chip(map, chip);
mutex_unlock(&chip->mutex);
return ret;
}
static int do_erase_oneblock(struct mtd_info *mtd, loff_t adr)
{
struct map_info *map = mtd->priv;
struct lpddr_private *lpddr = map->fldrv_priv;
int chipnum = adr >> lpddr->chipshift;
struct flchip *chip = &lpddr->chips[chipnum];
int ret;
mutex_lock(&chip->mutex);
ret = get_chip(map, chip, FL_ERASING);
if (ret) {
mutex_unlock(&chip->mutex);
return ret;
}
send_pfow_command(map, LPDDR_BLOCK_ERASE, adr, 0, NULL);
chip->state = FL_ERASING;
ret = wait_for_ready(map, chip, (1<<lpddr->qinfo->BlockEraseTime)*1000);
if (ret) {
printk(KERN_WARNING"%s Erase block error %d at : %llx\n",
map->name, ret, adr);
goto out;
}
out: put_chip(map, chip);
mutex_unlock(&chip->mutex);
return ret;
}
static int lpddr_read(struct mtd_info *mtd, loff_t adr, size_t len,
size_t *retlen, u_char *buf)
{
struct map_info *map = mtd->priv;
struct lpddr_private *lpddr = map->fldrv_priv;
int chipnum = adr >> lpddr->chipshift;
struct flchip *chip = &lpddr->chips[chipnum];
int ret = 0;
mutex_lock(&chip->mutex);
ret = get_chip(map, chip, FL_READY);
if (ret) {
mutex_unlock(&chip->mutex);
return ret;
}
map_copy_from(map, buf, adr, len);
*retlen = len;
put_chip(map, chip);
mutex_unlock(&chip->mutex);
return ret;
}
static int lpddr_point(struct mtd_info *mtd, loff_t adr, size_t len,
size_t *retlen, void **mtdbuf, resource_size_t *phys)
{
struct map_info *map = mtd->priv;
struct lpddr_private *lpddr = map->fldrv_priv;
int chipnum = adr >> lpddr->chipshift;
unsigned long ofs, last_end = 0;
struct flchip *chip = &lpddr->chips[chipnum];
int ret = 0;
if (!map->virt)
return -EINVAL;
/* ofs: offset within the first chip that the first read should start */
ofs = adr - (chipnum << lpddr->chipshift);
*mtdbuf = (void *)map->virt + chip->start + ofs;
while (len) {
unsigned long thislen;
if (chipnum >= lpddr->numchips)
break;
/* We cannot point across chips that are virtually disjoint */
if (!last_end)
last_end = chip->start;
else if (chip->start != last_end)
break;
if ((len + ofs - 1) >> lpddr->chipshift)
thislen = (1<<lpddr->chipshift) - ofs;
else
thislen = len;
/* get the chip */
mutex_lock(&chip->mutex);
ret = get_chip(map, chip, FL_POINT);
mutex_unlock(&chip->mutex);
if (ret)
break;
chip->state = FL_POINT;
chip->ref_point_counter++;
*retlen += thislen;
len -= thislen;
ofs = 0;
last_end += 1 << lpddr->chipshift;
chipnum++;
chip = &lpddr->chips[chipnum];
}
return 0;
}
static int lpddr_unpoint (struct mtd_info *mtd, loff_t adr, size_t len)
{
struct map_info *map = mtd->priv;
struct lpddr_private *lpddr = map->fldrv_priv;
int chipnum = adr >> lpddr->chipshift, err = 0;
unsigned long ofs;
/* ofs: offset within the first chip that the first read should start */
ofs = adr - (chipnum << lpddr->chipshift);
while (len) {
unsigned long thislen;
struct flchip *chip;
chip = &lpddr->chips[chipnum];
if (chipnum >= lpddr->numchips)
break;
if ((len + ofs - 1) >> lpddr->chipshift)
thislen = (1<<lpddr->chipshift) - ofs;
else
thislen = len;
mutex_lock(&chip->mutex);
if (chip->state == FL_POINT) {
chip->ref_point_counter--;
if (chip->ref_point_counter == 0)
chip->state = FL_READY;
} else {
printk(KERN_WARNING "%s: Warning: unpoint called on non"
"pointed region\n", map->name);
err = -EINVAL;
}
put_chip(map, chip);
mutex_unlock(&chip->mutex);
len -= thislen;
ofs = 0;
chipnum++;
}
return err;
}
static int lpddr_write_buffers(struct mtd_info *mtd, loff_t to, size_t len,
size_t *retlen, const u_char *buf)
{
struct kvec vec;
vec.iov_base = (void *) buf;
vec.iov_len = len;
return lpddr_writev(mtd, &vec, 1, to, retlen);
}
static int lpddr_writev(struct mtd_info *mtd, const struct kvec *vecs,
unsigned long count, loff_t to, size_t *retlen)
{
struct map_info *map = mtd->priv;
struct lpddr_private *lpddr = map->fldrv_priv;
int ret = 0;
int chipnum;
unsigned long ofs, vec_seek, i;
int wbufsize = 1 << lpddr->qinfo->BufSizeShift;
size_t len = 0;
for (i = 0; i < count; i++)
len += vecs[i].iov_len;
if (!len)
return 0;
chipnum = to >> lpddr->chipshift;
ofs = to;
vec_seek = 0;
do {
/* We must not cross write block boundaries */
int size = wbufsize - (ofs & (wbufsize-1));
if (size > len)
size = len;
ret = do_write_buffer(map, &lpddr->chips[chipnum],
ofs, &vecs, &vec_seek, size);
if (ret)
return ret;
ofs += size;
(*retlen) += size;
len -= size;
/* Be nice and reschedule with the chip in a usable
* state for other processes */
cond_resched();
} while (len);
return 0;
}
static int lpddr_erase(struct mtd_info *mtd, struct erase_info *instr)
{
unsigned long ofs, len;
int ret;
struct map_info *map = mtd->priv;
struct lpddr_private *lpddr = map->fldrv_priv;
int size = 1 << lpddr->qinfo->UniformBlockSizeShift;
ofs = instr->addr;
len = instr->len;
while (len > 0) {
ret = do_erase_oneblock(mtd, ofs);
if (ret)
return ret;
ofs += size;
len -= size;
}
instr->state = MTD_ERASE_DONE;
mtd_erase_callback(instr);
return 0;
}
#define DO_XXLOCK_LOCK 1
#define DO_XXLOCK_UNLOCK 2
static int do_xxlock(struct mtd_info *mtd, loff_t adr, uint32_t len, int thunk)
{
int ret = 0;
struct map_info *map = mtd->priv;
struct lpddr_private *lpddr = map->fldrv_priv;
int chipnum = adr >> lpddr->chipshift;
struct flchip *chip = &lpddr->chips[chipnum];
mutex_lock(&chip->mutex);
ret = get_chip(map, chip, FL_LOCKING);
if (ret) {
mutex_unlock(&chip->mutex);
return ret;
}
if (thunk == DO_XXLOCK_LOCK) {
send_pfow_command(map, LPDDR_LOCK_BLOCK, adr, adr + len, NULL);
chip->state = FL_LOCKING;
} else if (thunk == DO_XXLOCK_UNLOCK) {
send_pfow_command(map, LPDDR_UNLOCK_BLOCK, adr, adr + len, NULL);
chip->state = FL_UNLOCKING;
} else
BUG();
ret = wait_for_ready(map, chip, 1);
if (ret) {
printk(KERN_ERR "%s: block unlock error status %d \n",
map->name, ret);
goto out;
}
out: put_chip(map, chip);
mutex_unlock(&chip->mutex);
return ret;
}
static int lpddr_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
{
return do_xxlock(mtd, ofs, len, DO_XXLOCK_LOCK);
}
static int lpddr_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
{
return do_xxlock(mtd, ofs, len, DO_XXLOCK_UNLOCK);
}
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Alexey Korolev <akorolev@infradead.org>");
MODULE_DESCRIPTION("MTD driver for LPDDR flash chips");