[PATCH v2 09/15] mtd: rawnand: Provide a helper to get chip->data_buf

Miquel Raynal
2019-03-04T20:19:04Z

From: Boris Brezillon <bbrezillon@kernel.org>

We plan to move cache related fields to a pagecache struct in nand_chip
but some drivers access ->pagebuf directly to invalidate the cache
before they start using ->data_buf.

Let's provide an helper that returns a pointer to ->data_buf after
invalidating the cache.

Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
---
drivers/mtd/nand/raw/brcmnand/brcmnand.c | 7 +---
drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c | 4 +-
drivers/mtd/nand/raw/marvell_nand.c | 43 +++++++++-------------
drivers/mtd/nand/raw/nand_base.c | 7 ++--
drivers/mtd/nand/raw/nand_bbt.c | 4 +-
drivers/mtd/nand/raw/qcom_nandc.c | 8 ++--
drivers/mtd/nand/raw/sunxi_nand.c | 11 +++---
include/linux/mtd/rawnand.h | 21 +++++++++++
8 files changed, 56 insertions(+), 49 deletions(-)

diff --git a/drivers/mtd/nand/raw/brcmnand/brcmnand.c b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
index 482c6f093f99..ce0b8ffc7812 100644
--- a/drivers/mtd/nand/raw/brcmnand/brcmnand.c
+++ b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
@@ -1676,11 +1676,8 @@ static int brcmstb_nand_verify_erased_page(struct mtd_info *mtd,
int page = addr >> chip->page_shift;
int ret;

- if (!buf) {
- buf = chip->data_buf;
- /* Invalidate page cache */
- chip->pagebuf = -1;
- }
+ if (!buf)
+ buf = nand_get_data_buf(chip);

sas = mtd->oobsize / chip->ecc.steps;

diff --git a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
index ed405c9434fe..05f6f68e4e0d 100644
--- a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
+++ b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
@@ -1602,7 +1602,7 @@ static int mx23_check_transcription_stamp(struct gpmi_nand_data *this)
unsigned int search_area_size_in_strides;
unsigned int stride;
unsigned int page;
- uint8_t *buffer = chip->data_buf;
+ u8 *buffer = nand_get_data_buf(chip);
int saved_chip_number;
int found_an_ncb_fingerprint = false;

@@ -1664,7 +1664,7 @@ static int mx23_write_transcription_stamp(struct gpmi_nand_data *this)
unsigned int block;
unsigned int stride;
unsigned int page;
- uint8_t *buffer = chip->data_buf;
+ u8 *buffer = nand_get_data_buf(chip);
int saved_chip_number;
int status;

diff --git a/drivers/mtd/nand/raw/marvell_nand.c b/drivers/mtd/nand/raw/marvell_nand.c
index 84283c6bb0ff..e8023b32be93 100644
--- a/drivers/mtd/nand/raw/marvell_nand.c
+++ b/drivers/mtd/nand/raw/marvell_nand.c
@@ -1083,12 +1083,11 @@ static int marvell_nfc_hw_ecc_hmg_read_page(struct nand_chip *chip, u8 *buf,
*/
static int marvell_nfc_hw_ecc_hmg_read_oob_raw(struct nand_chip *chip, int page)
{
- /* Invalidate page cache */
- chip->pagebuf = -1;
+ u8 *buf = nand_get_data_buf(chip);

marvell_nfc_select_target(chip, chip->cur_cs);
- return marvell_nfc_hw_ecc_hmg_do_read_page(chip, chip->data_buf,
- chip->oob_poi, true, page);
+ return marvell_nfc_hw_ecc_hmg_do_read_page(chip, buf, chip->oob_poi,
+ true, page);
}

/* Hamming write helpers */
@@ -1179,15 +1178,13 @@ static int marvell_nfc_hw_ecc_hmg_write_oob_raw(struct nand_chip *chip,
int page)
{
struct mtd_info *mtd = nand_to_mtd(chip);
+ u8 *buf = nand_get_data_buf(chip);

- /* Invalidate page cache */
- chip->pagebuf = -1;
-
- memset(chip->data_buf, 0xFF, mtd->writesize);
+ memset(buf, 0xFF, mtd->writesize);

marvell_nfc_select_target(chip, chip->cur_cs);
- return marvell_nfc_hw_ecc_hmg_do_write_page(chip, chip->data_buf,
- chip->oob_poi, true, page);
+ return marvell_nfc_hw_ecc_hmg_do_write_page(chip, buf, chip->oob_poi,
+ true, page);
}

/* BCH read helpers */
@@ -1434,18 +1431,16 @@ static int marvell_nfc_hw_ecc_bch_read_page(struct nand_chip *chip,

static int marvell_nfc_hw_ecc_bch_read_oob_raw(struct nand_chip *chip, int page)
{
- /* Invalidate page cache */
- chip->pagebuf = -1;
+ u8 *buf = nand_get_data_buf(chip);

- return chip->ecc.read_page_raw(chip, chip->data_buf, true, page);
+ return chip->ecc.read_page_raw(chip, buf, true, page);
}

static int marvell_nfc_hw_ecc_bch_read_oob(struct nand_chip *chip, int page)
{
- /* Invalidate page cache */
- chip->pagebuf = -1;
+ u8 *buf = nand_get_data_buf(chip);

- return chip->ecc.read_page(chip, chip->data_buf, true, page);
+ return chip->ecc.read_page(chip, buf, true, page);
}

/* BCH write helpers */
@@ -1619,25 +1614,21 @@ static int marvell_nfc_hw_ecc_bch_write_oob_raw(struct nand_chip *chip,
int page)
{
struct mtd_info *mtd = nand_to_mtd(chip);
+ u8 *buf = nand_get_data_buf(chip);

- /* Invalidate page cache */
- chip->pagebuf = -1;
+ memset(buf, 0xFF, mtd->writesize);

- memset(chip->data_buf, 0xFF, mtd->writesize);
-
- return chip->ecc.write_page_raw(chip, chip->data_buf, true, page);
+ return chip->ecc.write_page_raw(chip, buf, true, page);
}

static int marvell_nfc_hw_ecc_bch_write_oob(struct nand_chip *chip, int page)
{
struct mtd_info *mtd = nand_to_mtd(chip);
+ u8 *buf = nand_get_data_buf(chip);

- /* Invalidate page cache */
- chip->pagebuf = -1;
+ memset(buf, 0xFF, mtd->writesize);

- memset(chip->data_buf, 0xFF, mtd->writesize);
-
- return chip->ecc.write_page(chip, chip->data_buf, true, page);
+ return chip->ecc.write_page(chip, buf, true, page);
}

/* NAND framework ->exec_op() hooks and related helpers */
diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c
index fea3f8b96558..4b10652b0b97 100644
--- a/drivers/mtd/nand/raw/nand_base.c
+++ b/drivers/mtd/nand/raw/nand_base.c
@@ -4033,10 +4033,9 @@ static int nand_do_write_ops(struct nand_chip *chip, loff_t to,
__func__, buf);
if (part_pagewr)
bytes = min_t(int, bytes - column, writelen);
- chip->pagebuf = -1;
- memset(chip->data_buf, 0xff, mtd->writesize);
- memcpy(&chip->data_buf[column], buf, bytes);
- wbuf = chip->data_buf;
+ wbuf = nand_get_data_buf(chip);
+ memset(wbuf, 0xff, mtd->writesize);
+ memcpy(&wbuf[column], buf, bytes);
}

if (unlikely(oob)) {
diff --git a/drivers/mtd/nand/raw/nand_bbt.c b/drivers/mtd/nand/raw/nand_bbt.c
index 1b722fe9213c..0b96c4cab967 100644
--- a/drivers/mtd/nand/raw/nand_bbt.c
+++ b/drivers/mtd/nand/raw/nand_bbt.c
@@ -901,7 +901,9 @@ static int write_bbt(struct nand_chip *this, uint8_t *buf,
static inline int nand_memory_bbt(struct nand_chip *this,
struct nand_bbt_descr *bd)
{
- return create_bbt(this, this->data_buf, bd, -1);
+ u8 *pagebuf = nand_get_data_buf(this);
+
+ return create_bbt(this, pagebuf, bd, -1);
}

/**
diff --git a/drivers/mtd/nand/raw/qcom_nandc.c b/drivers/mtd/nand/raw/qcom_nandc.c
index 46c62a31fa46..3f8005113fe2 100644
--- a/drivers/mtd/nand/raw/qcom_nandc.c
+++ b/drivers/mtd/nand/raw/qcom_nandc.c
@@ -1680,14 +1680,12 @@ check_for_erased_page(struct qcom_nand_host *host, u8 *data_buf,
u8 *cw_data_buf, *cw_oob_buf;
int cw, data_size, oob_size, ret = 0;

- if (!data_buf) {
- data_buf = chip->data_buf;
- chip->pagebuf = -1;
- }
+ if (!data_buf)
+ data_buf = nand_get_data_buf(chip);

if (!oob_buf) {
+ nand_get_data_buf(chip);
oob_buf = chip->oob_poi;
- chip->pagebuf = -1;
}

for_each_set_bit(cw, &uncorrectable_cws, ecc->steps) {
diff --git a/drivers/mtd/nand/raw/sunxi_nand.c b/drivers/mtd/nand/raw/sunxi_nand.c
index e828ee50a201..d5de0a7114bc 100644
--- a/drivers/mtd/nand/raw/sunxi_nand.c
+++ b/drivers/mtd/nand/raw/sunxi_nand.c
@@ -1426,20 +1426,19 @@ static int sunxi_nfc_hw_ecc_write_page_dma(struct nand_chip *chip,

static int sunxi_nfc_hw_ecc_read_oob(struct nand_chip *chip, int page)
{
- chip->pagebuf = -1;
+ u8 *buf = nand_get_data_buf(chip);

- return chip->ecc.read_page(chip, chip->data_buf, 1, page);
+ return chip->ecc.read_page(chip, buf, 1, page);
}

static int sunxi_nfc_hw_ecc_write_oob(struct nand_chip *chip, int page)
{
struct mtd_info *mtd = nand_to_mtd(chip);
+ u8 *buf = nand_get_data_buf(chip);
int ret;

- chip->pagebuf = -1;
-
- memset(chip->data_buf, 0xff, mtd->writesize);
- ret = chip->ecc.write_page(chip, chip->data_buf, 1, page);
+ memset(buf, 0xff, mtd->writesize);
+ ret = chip->ecc.write_page(chip, buf, 1, page);
if (ret)
return ret;

diff --git a/include/linux/mtd/rawnand.h b/include/linux/mtd/rawnand.h
index dfeedfe2f3e0..e62c3ab4e0f7 100644
--- a/include/linux/mtd/rawnand.h
+++ b/include/linux/mtd/rawnand.h
@@ -1358,4 +1358,25 @@ int nand_gpio_waitrdy(struct nand_chip *chip, struct gpio_desc *gpiod,
void nand_select_target(struct nand_chip *chip, unsigned int cs);
void nand_deselect_target(struct nand_chip *chip);

+/**
+ * nand_get_data_buf() - Get the internal page buffer
+ * @chip: NAND chip object
+ *
+ * Returns the pre-allocated page buffer after invalidating the cache. This
+ * function should be used by drivers that do not want to allocate their own
+ * bounce buffer and still need such a buffer for specific operations (most
+ * commonly when reading OOB data only).
+ *
+ * Be careful to never call this function in the write/write_oob path, because
+ * the core may have placed the data to be written out in this buffer.
+ *
+ * Return: pointer to the page cache buffer
+ */
+static inline void *nand_get_data_buf(struct nand_chip *chip)
+{
+ chip->pagebuf = -1;
+
+ return chip->data_buf;
+}
+
#endif /* __LINUX_MTD_RAWNAND_H */
--
2.19.1