2017-11-30 14:42:46

by Bean Huo (beanhuo)

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

Hi, Cyrille

Finally, I get your comments, thanks.

>Hi Bean,
>
>Le 11/11/2017 à 21:49, Bean Huo (beanhuo) a écrit :
>> 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.
>
When the program/erase failed, or there is the error during
Erasing/programming, user space always gets the status of the
previous operation is successful. Because current spi_nor_fsr_ready()
only checks FSR ready bit. Even if failure/error happened, spi nor
device still can go into the ready stage. This is what I want to say.
So, the device ready and the operation failure 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.
>
I am not a native English speaker, hopefully I can make big progress on writing.

>> Signed-off-by: beanhuo <[email protected]>
>> ---
>> 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.
>
Yes, I already re-sent this patch which merged these two line into one line.

>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/
>

Yes, it is one time programmable space.

>> +
>> + 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 = "
>
I thought we care more on the code, rather than comment, thanks for reviewing.

>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 */
>>