Re: [PATCH V1] drivers:mtd:spi-nor:checkup FSR error bits

From: Cyrille Pitchen
Date: Thu Nov 30 2017 - 08:31:25 EST


Hi Bean,

Le 11/11/2017 Ã 21:49, Bean Huo (beanhuo) a Ãcrit :
> For the Micron SPI NOR, when the erase/program operation fails, especially,

To be verified but I think you'd rather remove "the" words in this case:

"For Micron SPI NOR memories, when erase/program operation fails, especially ..."

Maybe no comma after "especially".

> for the failure results from intending to modify protected space, spi-nor
> upper layers still get the return which shows the operation succeeds.
> this because spi_nor_fsr_ready() only uses bit.7 to device whether ready.

"This": missing capital letter and maybe a verb too.

> For the most cases, even the error of erase/program occurs, SPI NOR device
> is still ready. The device ready and the error are two different cases.

I don't really understand what you mean here.

> This patch is to fixup this issue and adding FSR (flag status register)

This patch fixes the issue by checking relevant bits in the FSR.

> error bits checkup.
> The FSR(flag status register) is a powerful tool to investigate the staus

"The FSR (flag status register)": please insert a space ' '.

s/staus/status/


> of device,checking information regarding what is actually doing the memory

"of device, checking": missing space
> and detecting possible error conditions.
>

Globally, I think you need to reword your commit message. IMHO, it is not
clear though I think I've mostly understood what you meant reading the
actual source code.

> Signed-off-by: beanhuo <beanhuo@xxxxxxxxxx>
> ---
> drivers/mtd/spi-nor/spi-nor.c | 19 +++++++++++++++++--
> include/linux/mtd/spi-nor.h | 6 +++++-
> 2 files changed, 22 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
> index bc266f7..200e814 100644
> --- a/drivers/mtd/spi-nor/spi-nor.c
> +++ b/drivers/mtd/spi-nor/spi-nor.c
> @@ -330,8 +330,23 @@ static inline int spi_nor_fsr_ready(struct spi_nor *nor)
> int fsr = read_fsr(nor);
> if (fsr < 0)
> return fsr;
> - else
> - return fsr & FSR_READY;
> +
> + if (fsr & (FSR_E_ERR | FSR_P_ERR)) {
> + if (fsr & FSR_E_ERR)
> + dev_err(nor->dev, "Erase operation failed.\n");
> + else
> + dev_err(nor->dev, "Program operation failed.\n");
> +
> + if (fsr & FSR_PT_ERR)
> + dev_err(nor->dev,
> + "The operation has attempted to modify the protected"

A space ' ' is missing after "protected".
Also please verify next version passes the checkpatch test because this
version doesn't.

I think you should check the verb tense consistency:
[...] operation failed. The operation attempted [...]

Also maybe you should write "a protected sector" or "some protected sector":
"the protected sector" sounds like there is only one protected sector.

> + "sector or the locked OPT space.\n");

You meant OTP (One Time Programmable), didn't you ? s/OPT/OTP/

> +
> + nor->write_reg(nor, SPINOR_OP_CLFSR, NULL, 0);
> + return -EIO;
> + }
> +
> + return fsr & FSR_READY;
> }
>
> static int spi_nor_ready(struct spi_nor *nor)
> diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
> index d0c66a0..46b5608 100644
> --- a/include/linux/mtd/spi-nor.h
> +++ b/include/linux/mtd/spi-nor.h
> @@ -61,6 +61,7 @@
> #define SPINOR_OP_RDSFDP 0x5a /* Read SFDP */
> #define SPINOR_OP_RDCR 0x35 /* Read configuration register */
> #define SPINOR_OP_RDFSR 0x70 /* Read flag status register */
> +#define SPINOR_OP_CLFSR 0x50 /* Clear flag status register */
>
> /* 4-byte address opcodes - used on Spansion and some Macronix flashes. */
> #define SPINOR_OP_READ_4B 0x13 /* Read data bytes (low frequency) */
> @@ -130,7 +131,10 @@
> #define EVCR_QUAD_EN_MICRON BIT(7) /* Micron Quad I/O */
>
> /* Flag Status Register bits */
> -#define FSR_READY BIT(7)
> +#define FSR_READY BIT(7) /* Device status, 0 = Busy,1 = Ready */

You may insert a space ' ' between "Busy," and "1 = "

Best regards,

Cyrille

> +#define FSR_E_ERR BIT(5) /* Erase operation status */
> +#define FSR_P_ERR BIT(4) /* Program operation status */
> +#define FSR_PT_ERR BIT(1) /* Protection error bit */
>
> /* Configuration Register bits. */
> #define CR_QUAD_EN_SPAN BIT(1) /* Spansion Quad I/O */
>