Re: [PATCH v2] mtd: micron-st: enable lock/unlock for mt25qu512a

From: SHUKLA Mamta Ramendra
Date: Thu Oct 05 2023 - 10:48:07 EST




On 05.10.23 15:51, Tudor Ambarus wrote:
> [Some people who received this message don't often get email from tudor.ambarus@xxxxxxxxxx. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
>
> This email is not from Hexagon’s Office 365 instance. Please be careful while clicking links, opening attachments, or replying to this email.
>
>
> On 10/5/23 10:21, SHUKLA Mamta Ramendra wrote:
>
> cut
>
>>>
>>> and the second one will add just the BP support, something like:
>>> diff --git a/drivers/mtd/spi-nor/micron-st.c
>>> b/drivers/mtd/spi-nor/micron-st.c
>>> index a8da1f18e335..fdafbfa0f936 100644
>>> --- a/drivers/mtd/spi-nor/micron-st.c
>>> +++ b/drivers/mtd/spi-nor/micron-st.c
>>> @@ -405,6 +405,8 @@ static const struct flash_info st_nor_parts[] = {
>>> }, {
>>> .id = SNOR_ID(0x20, 0xbb, 0x20, 0x10, 0x44, 0x00),
>>> .name = "mt25qu512a",
>>> + .flags = SPI_NOR_HAS_LOCK | SPI_NOR_HAS_TB |
>>> SPI_NOR_4BIT_BP |
>>> + SPI_NOR_BP3_SR_BIT6,
>>> .mfr_flags = USE_FSR,
>>> }, {
>>> .id = SNOR_ID(0x20, 0xbb, 0x20),
>>>
>>> Of course, I expect you to run again the mtd_debug tests and also verify
>>> the locking. Thanks!
>>
>> I applied both changes as mentioned above i.e
>> 1] Switch to SFDP and 2] Using BP Flags.
>>
>> Case 1: Use BP Flags and Switch to SFDP
>> With both these changes, the lock/unlock doesn't work.
>>
>> ## x86-64-smarc-evk-uwd0j0007 # uname -r
>> 6.6.0-rc2
>>
>> # flash_lock -i /dev/mtd0
>> Device: /dev/mtd0
>> Start: 0
>> Len: 0x4000000
>> Lock status: unlocked
>> Return code: 0
>> # flash_lock -l /dev/mtd0
>> flash_lock: error!: could not lock device: /dev/mtd0
>>
>> error 5 (Input/output error)
>>
>>
>> I suspected this is because of miscalculation of BP bits, like the
>> possibility mentioned here:
>> https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git/commit/?h=spi-nor/next&id=3ea3f0ac242c86c0275d347ab8c92bf1eb854b49
>>
>>
>> But further checked size, it is correct:
>>
>> # mtd_debug info /dev/mtd0
>> mtd.type = MTD_NORFLASH
>> mtd.flags = MTD_CAP_NORFLASH
>> mtd.size = 67108864 (64M)
>> mtd.erasesize = 4096 (4K)
>> mtd.writesize = 1
>> mtd.oobsize = 0
>> regions = 0
>>
>> And rest of read/write functions work as expected.
>>
>> Any suggestions about this?
>>
>> Case 2: Just added BP flags, rest of the size, mfr_flags, fixup flags
>> kept as it is.
>
> would you please detail what exact definitions you used in case 2? Send
> us the diff please.
Case 2: Adding Flags for BP

diff --git a/drivers/mtd/spi-nor/micron-st.c
b/drivers/mtd/spi-nor/micron-st.c
index 4afcfc57c896..6c8cabbead2e 100644
--- a/drivers/mtd/spi-nor/micron-st.c
+++ b/drivers/mtd/spi-nor/micron-st.c
@@ -405,6 +405,8 @@ static const struct flash_info st_nor_parts[] = {
}, {
.id = SNOR_ID(0x20, 0xbb, 0x20, 0x10, 0x44, 0x00),
.name = "mt25qu512a",
+ .flags = SPI_NOR_HAS_LOCK | SPI_NOR_HAS_TB |
SPI_NOR_4BIT_BP |
+ SPI_NOR_BP3_SR_BIT6,
.size = SZ_64M,
.no_sfdp_flags = SECT_4K | SPI_NOR_DUAL_READ |
SPI_NOR_QUAD_READ,
.fixup_flags = SPI_NOR_4B_OPCODES,


-----------------------------------------------------------------
Case 1: BP Flags and removed size, and no_sfdp so by default expecting
to read SFDP

diff --git a/drivers/mtd/spi-nor/micron-st.c
b/drivers/mtd/spi-nor/micron-st.c
index 6c8cabbead2e..4feb03ee2d13 100644
--- a/drivers/mtd/spi-nor/micron-st.c
+++ b/drivers/mtd/spi-nor/micron-st.c
@@ -407,9 +407,6 @@ static const struct flash_info st_nor_parts[] = {
.name = "mt25qu512a",
.flags = SPI_NOR_HAS_LOCK | SPI_NOR_HAS_TB |
SPI_NOR_4BIT_BP |
SPI_NOR_BP3_SR_BIT6,
- .size = SZ_64M,
- .no_sfdp_flags = SECT_4K | SPI_NOR_DUAL_READ |
SPI_NOR_QUAD_READ,
- .fixup_flags = SPI_NOR_4B_OPCODES,
.mfr_flags = USE_FSR,
}, {



>
> Cheers,
> ta
>
>> Lock/unlock works.
>>
>> ## x86-64-smarc-evk-uwd0j0007 # uname -r
>> 6.6.0-rc2
>>
>> # flash_lock -i /dev/mtd0
>> Start: 0
>> Len: 0x4000000
>> Lock status: unlocked
>> Return code: 0
>>
>> # flash_lock -l /dev/mtd0
>> # flash_lock -i /dev/mtd0
>> Device: /dev/mtd0
>> Start: 0
>> Len: 0x4000000
>> Lock status: locked
>> Return code: 1
>>
>> ## x86-64-smarc-evk-uwd0j0007 # mtd_debug erase /dev/mtd0 0 1048576
>> [ 413.472411] spi-nor spi-PRP0001:00: Erase operation failed.
>> [ 413.478084] spi-nor spi-PRP0001:00: Attempted to modify a protected
>> sector.
>> MEMERASE: Input/output error
>>
>> # flash_lock -u /dev/mtd0
>> # flash_lock -i /dev/mtd0
>> Device: /dev/mtd0
>> Start: 0
>> Len: 0x4000000
>> Lock status: unlocked
>> Return code: 0
>>
>> ## x86-64-smarc-evk-uwd0j0007 # mtd_debug erase /dev/mtd0 0 1048576
>> Erased 1048576 bytes from address 0x00000000 in flash
>>
>>
>> Further I tested on stable 6.5.5 Kernel with old way of Flash Info
>> Format and which has forced PARSE_SFDP Flag, no issues with lock/unlock.
>>
>>

---
Mamta