diff options
Diffstat (limited to 'drivers/mtd/lpddr/lpddr_cmds.c')
| -rw-r--r-- | drivers/mtd/lpddr/lpddr_cmds.c | 748 |
1 files changed, 748 insertions, 0 deletions
diff --git a/drivers/mtd/lpddr/lpddr_cmds.c b/drivers/mtd/lpddr/lpddr_cmds.c new file mode 100644 index 000000000..947bb710b --- /dev/null +++ b/drivers/mtd/lpddr/lpddr_cmds.c @@ -0,0 +1,748 @@ +/* + * 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_array(lpddr->numchips, sizeof(struct flchip_shared), + GFP_KERNEL); + if (!shared) { + 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; + } + + 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"); 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