mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-09-30 06:10:56 +00:00
Code Issues Releases Wiki Activity

mtd: spinand: use the spi-mem poll status APIs

Browse source 
Make use of spi-mem poll status APIs to let advanced controllers
optimize wait operations.
This should also fix the high CPU usage for system that don't have
a dedicated STATUS poll block logic.

Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com>
Signed-off-by: Christophe Kerello <christophe.kerello@foss.st.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Acked-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20210518162754.15940-3-patrice.chotard@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Patrice Chotard 2021-05-18 18:27:53 +02:00 committed by Mark Brown
parent c955a0cc8a
commit 8941cd8d29
No known key found for this signature in database
GPG key ID: 24D68B725D5487D0
2 changed files with 54 additions and 13 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

45
drivers/mtd/nand/spi/core.c
View file

@ -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_WAITRDY_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;

22
include/linux/mtd/spinand.h
View file

@ -170,6 +170,28 @@ struct spinand_op;
struct spinand_device;
#define SPINAND_MAX_ID_LEN 4
/*
* For erase, write and read operation, we got the following timings :
* tBERS (erase) 1ms to 4ms
* tPROG 300us to 400us
* tREAD 25us to 100us
* In order to minimize latency, the min value is divided by 4 for the
* initial delay, and dividing by 20 for the poll delay.
* For reset, 5us/10us/500us if the device is respectively
* reading/programming/erasing when the RESET occurs. Since we always
* issue a RESET when the device is IDLE, 5us is selected for both initial
* and poll delay.
*/
#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_WAITRDY_TIMEOUT_MS 400
/**
* struct spinand_id - SPI NAND id structure