[PATCH v3 2/3] mtd: spinand: use the spi-mem poll status APIs

patrice.chotard
2021-05-18T09:42:36Z

From: Patrice Chotard <patrice.chotard@foss.st.com>

Make use of spi-mem poll status APIs to let advanced controllers
optimize wait operations.

Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com>
Signed-off-by: Christophe Kerello <christophe.kerello@foss.st.com>
---
Changes in v3:
- Add initial_delay_us and polling_delay_us parameters to spinand_wait()
- Add SPINAND_READ/WRITE/ERASE/RESET_INITIAL_DELAY_US and
SPINAND_READ/WRITE/ERASE/RESET_POLL_DELAY_US defines.

Changes in v2:
- non-offload case is now managed by spi_mem_poll_status()

drivers/mtd/nand/spi/core.c | 45 ++++++++++++++++++++++++++-----------
include/linux/mtd/spinand.h | 11 ++++++++-
2 files changed, 42 insertions(+), 14 deletions(-)

diff --git a/drivers/mtd/nand/spi/core.c b/drivers/mtd/nand/spi/core.c
index 17f63f95f4a2..ef2a692ab5b6 100644
--- a/drivers/mtd/nand/spi/core.c
+++ b/drivers/mtd/nand/spi/core.c
@@ -473,20 +473,26 @@ static int spinand_erase_op(struct spinand_device *spinand,
return spi_mem_exec_op(spinand->spimem, &op);
}

-static int spinand_wait(struct spinand_device *spinand, u8 *s)
+static int spinand_wait(struct spinand_device *spinand,
+ unsigned long initial_delay_us,
+ unsigned long poll_delay_us,
+ u8 *s)
{
- unsigned long timeo = jiffies + msecs_to_jiffies(400);
+ struct spi_mem_op op = SPINAND_GET_FEATURE_OP(REG_STATUS,
+ spinand->scratchbuf);
u8 status;
int ret;

- do {
- ret = spinand_read_status(spinand, &status);
- if (ret)
- return ret;
+ ret = spi_mem_poll_status(spinand->spimem, &op, STATUS_BUSY, 0,
+ initial_delay_us,
+ poll_delay_us,
+ SPINAND_STATUS_TIMEOUT_MS);
+ if (ret)
+ return ret;

- if (!(status & STATUS_BUSY))
- goto out;
- } while (time_before(jiffies, timeo));
+ status = *spinand->scratchbuf;
+ if (!(status & STATUS_BUSY))
+ goto out;

/*
* Extra read, just in case the STATUS_READY bit has changed
@@ -526,7 +532,10 @@ static int spinand_reset_op(struct spinand_device *spinand)
if (ret)
return ret;

- return spinand_wait(spinand, NULL);
+ return spinand_wait(spinand,
+ SPINAND_RESET_INITIAL_DELAY_US,
+ SPINAND_RESET_POLL_DELAY_US,
+ NULL);
}

static int spinand_lock_block(struct spinand_device *spinand, u8 lock)
@@ -549,7 +558,10 @@ static int spinand_read_page(struct spinand_device *spinand,
if (ret)
return ret;

- ret = spinand_wait(spinand, &status);
+ ret = spinand_wait(spinand,
+ SPINAND_READ_INITIAL_DELAY_US,
+ SPINAND_READ_POLL_DELAY_US,
+ &status);
if (ret < 0)
return ret;

@@ -585,7 +597,10 @@ static int spinand_write_page(struct spinand_device *spinand,
if (ret)
return ret;

- ret = spinand_wait(spinand, &status);
+ ret = spinand_wait(spinand,
+ SPINAND_WRITE_INITIAL_DELAY_US,
+ SPINAND_WRITE_POLL_DELAY_US,
+ &status);
if (!ret && (status & STATUS_PROG_FAILED))
return -EIO;

@@ -768,7 +783,11 @@ static int spinand_erase(struct nand_device *nand, const struct nand_pos *pos)
if (ret)
return ret;

- ret = spinand_wait(spinand, &status);
+ ret = spinand_wait(spinand,
+ SPINAND_ERASE_INITIAL_DELAY_US,
+ SPINAND_ERASE_POLL_DELAY_US,
+ &status);
+
if (!ret && (status & STATUS_ERASE_FAILED))
ret = -EIO;

diff --git a/include/linux/mtd/spinand.h b/include/linux/mtd/spinand.h
index 6bb92f26833e..180c1fa64e62 100644
--- a/include/linux/mtd/spinand.h
+++ b/include/linux/mtd/spinand.h
@@ -169,7 +169,16 @@
struct spinand_op;
struct spinand_device;

-#define SPINAND_MAX_ID_LEN 4
+#define SPINAND_MAX_ID_LEN 4
+#define SPINAND_READ_INITIAL_DELAY_US 6
+#define SPINAND_READ_POLL_DELAY_US 5
+#define SPINAND_RESET_INITIAL_DELAY_US 5
+#define SPINAND_RESET_POLL_DELAY_US 5
+#define SPINAND_WRITE_INITIAL_DELAY_US 75
+#define SPINAND_WRITE_POLL_DELAY_US 15
+#define SPINAND_ERASE_INITIAL_DELAY_US 250
+#define SPINAND_ERASE_POLL_DELAY_US 50
+#define SPINAND_STATUS_TIMEOUT_MS 400

/**
* struct spinand_id - SPI NAND id structure
--
2.17.1