mtd: nand: add 'oob_required' argument to NAND {read,write}_page interfaces
New NAND controllers can perform read/write via HW engines which don't expose
OOB data in their DMA mode. To reflect this, we should rework the nand_chip /
nand_ecc_ctrl interfaces that assume that drivers will always read/write OOB
data in the nand_chip.oob_poi buffer. A better interface includes a boolean
argument that explicitly tells the callee when OOB data is requested by the
calling layer (for reading/writing to/from nand_chip.oob_poi).
This patch adds the 'oob_required' parameter to each relevant {read,write}_page
interface; all 'oob_required' parameters are left unused for now. The next
patch will set the parameter properly in the nand_base.c callers, and follow-up
patches will make use of 'oob_required' in some of the callee functions.
Note that currently, there is no harm in ignoring the 'oob_required' parameter
and *always* utilizing nand_chip.oob_poi, but there can be
performance/complexity/design benefits from avoiding filling oob_poi in the
common case. I will try to implement this for some drivers which can be ported
easily.
Note: I couldn't compile-test all of these easily, as some had ARCH
dependencies.
[dwmw2: Merge later 1/0 vs. true/false cleanup]
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Acked-by: Jiandong Zheng <jdzheng@broadcom.com>
Acked-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 5ec4d2c..6d4894a 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -1066,12 +1066,13 @@
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: buffer to store read data
+ * @oob_required: caller requires OOB data read to chip->oob_poi
* @page: page number to read
*
* Not for syndrome calculating ECC controllers, which use a special oob layout.
*/
static int nand_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
- uint8_t *buf, int page)
+ uint8_t *buf, int oob_required, int page)
{
chip->read_buf(mtd, buf, mtd->writesize);
chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
@@ -1083,13 +1084,14 @@
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: buffer to store read data
+ * @oob_required: caller requires OOB data read to chip->oob_poi
* @page: page number to read
*
* We need a special oob layout and handling even when OOB isn't used.
*/
static int nand_read_page_raw_syndrome(struct mtd_info *mtd,
- struct nand_chip *chip,
- uint8_t *buf, int page)
+ struct nand_chip *chip, uint8_t *buf,
+ int oob_required, int page)
{
int eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
@@ -1126,10 +1128,11 @@
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: buffer to store read data
+ * @oob_required: caller requires OOB data read to chip->oob_poi
* @page: page number to read
*/
static int nand_read_page_swecc(struct mtd_info *mtd, struct nand_chip *chip,
- uint8_t *buf, int page)
+ uint8_t *buf, int oob_required, int page)
{
int i, eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
@@ -1140,7 +1143,7 @@
uint32_t *eccpos = chip->ecc.layout->eccpos;
unsigned int max_bitflips = 0;
- chip->ecc.read_page_raw(mtd, chip, buf, page);
+ chip->ecc.read_page_raw(mtd, chip, buf, 1, page);
for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize)
chip->ecc.calculate(mtd, p, &ecc_calc[i]);
@@ -1263,12 +1266,13 @@
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: buffer to store read data
+ * @oob_required: caller requires OOB data read to chip->oob_poi
* @page: page number to read
*
* Not for syndrome calculating ECC controllers which need a special oob layout.
*/
static int nand_read_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
- uint8_t *buf, int page)
+ uint8_t *buf, int oob_required, int page)
{
int i, eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
@@ -1311,6 +1315,7 @@
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: buffer to store read data
+ * @oob_required: caller requires OOB data read to chip->oob_poi
* @page: page number to read
*
* Hardware ECC for large page chips, require OOB to be read first. For this
@@ -1320,7 +1325,7 @@
* the data area, by overwriting the NAND manufacturer bad block markings.
*/
static int nand_read_page_hwecc_oob_first(struct mtd_info *mtd,
- struct nand_chip *chip, uint8_t *buf, int page)
+ struct nand_chip *chip, uint8_t *buf, int oob_required, int page)
{
int i, eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
@@ -1362,13 +1367,14 @@
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: buffer to store read data
+ * @oob_required: caller requires OOB data read to chip->oob_poi
* @page: page number to read
*
* The hw generator calculates the error syndrome automatically. Therefore we
* need a special oob layout and handling.
*/
static int nand_read_page_syndrome(struct mtd_info *mtd, struct nand_chip *chip,
- uint8_t *buf, int page)
+ uint8_t *buf, int oob_required, int page)
{
int i, eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
@@ -1514,14 +1520,14 @@
* the read methods return max bitflips per ecc step.
*/
if (unlikely(ops->mode == MTD_OPS_RAW))
- ret = chip->ecc.read_page_raw(mtd, chip,
- bufpoi, page);
+ ret = chip->ecc.read_page_raw(mtd, chip, bufpoi,
+ 1, page);
else if (!aligned && NAND_SUBPAGE_READ(chip) && !oob)
ret = chip->ecc.read_subpage(mtd, chip,
col, bytes, bufpoi);
else
ret = chip->ecc.read_page(mtd, chip, bufpoi,
- page);
+ 1, page);
if (ret < 0) {
if (!aligned)
/* Invalidate page cache */
@@ -1913,11 +1919,12 @@
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: data buffer
+ * @oob_required: must write chip->oob_poi to OOB
*
* Not for syndrome calculating ECC controllers, which use a special oob layout.
*/
static void nand_write_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
- const uint8_t *buf)
+ const uint8_t *buf, int oob_required)
{
chip->write_buf(mtd, buf, mtd->writesize);
chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
@@ -1928,12 +1935,13 @@
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: data buffer
+ * @oob_required: must write chip->oob_poi to OOB
*
* We need a special oob layout and handling even when ECC isn't checked.
*/
static void nand_write_page_raw_syndrome(struct mtd_info *mtd,
struct nand_chip *chip,
- const uint8_t *buf)
+ const uint8_t *buf, int oob_required)
{
int eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
@@ -1967,9 +1975,10 @@
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: data buffer
+ * @oob_required: must write chip->oob_poi to OOB
*/
static void nand_write_page_swecc(struct mtd_info *mtd, struct nand_chip *chip,
- const uint8_t *buf)
+ const uint8_t *buf, int oob_required)
{
int i, eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
@@ -1985,7 +1994,7 @@
for (i = 0; i < chip->ecc.total; i++)
chip->oob_poi[eccpos[i]] = ecc_calc[i];
- chip->ecc.write_page_raw(mtd, chip, buf);
+ chip->ecc.write_page_raw(mtd, chip, buf, 1);
}
/**
@@ -1993,9 +2002,10 @@
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: data buffer
+ * @oob_required: must write chip->oob_poi to OOB
*/
static void nand_write_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
- const uint8_t *buf)
+ const uint8_t *buf, int oob_required)
{
int i, eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
@@ -2021,12 +2031,14 @@
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: data buffer
+ * @oob_required: must write chip->oob_poi to OOB
*
* The hw generator calculates the error syndrome automatically. Therefore we
* need a special oob layout and handling.
*/
static void nand_write_page_syndrome(struct mtd_info *mtd,
- struct nand_chip *chip, const uint8_t *buf)
+ struct nand_chip *chip,
+ const uint8_t *buf, int oob_required)
{
int i, eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
@@ -2065,21 +2077,23 @@
* @mtd: MTD device structure
* @chip: NAND chip descriptor
* @buf: the data to write
+ * @oob_required: must write chip->oob_poi to OOB
* @page: page number to write
* @cached: cached programming
* @raw: use _raw version of write_page
*/
static int nand_write_page(struct mtd_info *mtd, struct nand_chip *chip,
- const uint8_t *buf, int page, int cached, int raw)
+ const uint8_t *buf, int oob_required, int page,
+ int cached, int raw)
{
int status;
chip->cmdfunc(mtd, NAND_CMD_SEQIN, 0x00, page);
if (unlikely(raw))
- chip->ecc.write_page_raw(mtd, chip, buf);
+ chip->ecc.write_page_raw(mtd, chip, buf, oob_required);
else
- chip->ecc.write_page(mtd, chip, buf);
+ chip->ecc.write_page(mtd, chip, buf, oob_required);
/*
* Cached progamming disabled for now. Not sure if it's worth the
@@ -2261,7 +2275,7 @@
memset(chip->oob_poi, 0xff, mtd->oobsize);
}
- ret = chip->write_page(mtd, chip, wbuf, page, cached,
+ ret = chip->write_page(mtd, chip, wbuf, 1, page, cached,
(ops->mode == MTD_OPS_RAW));
if (ret)
break;