diff options
| author | Masahiro Yamada <yamada.masahiro@socionext.com> | 2017-03-30 17:15:05 +0900 |
|---|---|---|
| committer | Boris Brezillon <boris.brezillon@free-electrons.com> | 2017-04-25 14:18:38 +0200 |
| commit | 477544c62a84d3bacd9f90ba75ffc16c04d78071 (patch) | |
| tree | e9a1cdeaaa0862bd8d64483b14c0883357766a48 | |
| parent | 3deb9979c7319bc7846d1aac528a9db85162960a (diff) | |
mtd: nand: allow drivers to request minimum alignment for passed buffer
In some cases, nand_do_{read,write}_ops is passed with unaligned
ops->datbuf. Drivers using DMA will be unhappy about unaligned
buffer.
The new struct member, buf_align, represents the minimum alignment
the driver require for the buffer. If the buffer passed from the
upper MTD layer does not have enough alignment, nand_do_*_ops will
use bufpoi.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
| -rw-r--r-- | drivers/mtd/nand/nand_base.c | 10 | ||||
| -rw-r--r-- | include/linux/mtd/nand.h | 2 |
2 files changed, 10 insertions, 2 deletions
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index c796d0e4039a..ed49a1d634b0 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -1954,7 +1954,9 @@ static int nand_do_read_ops(struct mtd_info *mtd, loff_t from, if (!aligned) use_bufpoi = 1; else if (chip->options & NAND_USE_BOUNCE_BUFFER) - use_bufpoi = !virt_addr_valid(buf); + use_bufpoi = !virt_addr_valid(buf) || + !IS_ALIGNED((unsigned long)buf, + chip->buf_align); else use_bufpoi = 0; @@ -2810,7 +2812,9 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to, if (part_pagewr) use_bufpoi = 1; else if (chip->options & NAND_USE_BOUNCE_BUFFER) - use_bufpoi = !virt_addr_valid(buf); + use_bufpoi = !virt_addr_valid(buf) || + !IS_ALIGNED((unsigned long)buf, + chip->buf_align); else use_bufpoi = 0; @@ -3429,6 +3433,8 @@ static void nand_set_defaults(struct nand_chip *chip) nand_hw_control_init(chip->controller); } + if (!chip->buf_align) + chip->buf_align = 1; } /* Sanitize ONFI strings so we can safely print them */ diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h index 9e0c93c44bef..8f67b1581683 100644 --- a/include/linux/mtd/nand.h +++ b/include/linux/mtd/nand.h @@ -755,6 +755,7 @@ struct nand_manufacturer_ops { * setting the read-retry mode. Mostly needed for MLC NAND. * @ecc: [BOARDSPECIFIC] ECC control structure * @buffers: buffer structure for read/write + * @buf_align: minimum buffer alignment required by a platform * @hwcontrol: platform-specific hardware control structure * @erase: [REPLACEABLE] erase function * @scan_bbt: [REPLACEABLE] function to scan bad block table @@ -905,6 +906,7 @@ struct nand_chip { struct nand_ecc_ctrl ecc; struct nand_buffers *buffers; + unsigned long buf_align; struct nand_hw_control hwcontrol; uint8_t *bbt; |