[U-Boot] [EXT] Re: [Patch V3] drivers: mtd :spi: Enable 4B opcodes for SPANSION s25fl512s

Mon Jul 22 06:06:23 UTC 2019

On Mon, Jul 22, 2019 at 11:11 AM Ashish Kumar <ashish.kumar at nxp.com> wrote:
>
>
>
> > -----Original Message-----
> > From: Vignesh Raghavendra <vigneshr at ti.com>
> > Sent: Friday, July 19, 2019 11:41 PM
> > To: Ashish Kumar <ashish.kumar at nxp.com>; Jagan Teki
> > <jagan at amarulasolutions.com>; hs at denx.de
> > Cc: U-Boot-Denx <u-boot at lists.denx.de>
> > Subject: Re: [EXT] Re: [Patch V3] drivers: mtd :spi: Enable 4B opcodes for
> > SPANSION s25fl512s
> >
> > Caution: EXT Email
> >
> > >>>>>> s25fs512s and s25fl512s which has same JEDEC ID but only varies
> > >>>>>> in operating volatge so s25fs512s shares same command set as
> > >> mentioned
> > >>>>>> below:
> > >>>>>> – Serial Command subset and footprint compatible with S25FL-A,
> > >>>>>> S25FL-K, S25FL-P, and S25FL-S SPI families – Multi I/O Command
> > >>>>>> subset and footprint compatible with S25FL-P, and S25FL-S SPI
> > >>>>>> families
> > >>>>>>
> > >>>>>> Signed-off-by: Ashish Kumar <Ashish.Kumar at nxp.com>
> > >>>>>> ---
> > >>>>>> v3:
> > >>>>>> 1. Add version info, rebase to top.
> > >>>>>> 2. Re-word commit message.
> > >>>>>> v2:
> > >>>>>> 1. Adding more description in commit msg.
> > >>>>>> 2. consolidating "" and  "" in single patch.
> > >>>>>>
> > >>>>>>  drivers/mtd/spi/spi-nor-ids.c | 2 +-
> > >>>>>>  1 file changed, 1 insertion(+), 1 deletion(-)
> > >>>>>>
> > >>>>>> diff --git a/drivers/mtd/spi/spi-nor-ids.c
> > >>>>>> b/drivers/mtd/spi/spi-nor-ids.c index 3217fc6..a992966 100644
> > >>>>>> --- a/drivers/mtd/spi/spi-nor-ids.c
> > >>>>>> +++ b/drivers/mtd/spi/spi-nor-ids.c
> > >>>>>> @@ -181,7 +181,7 @@ const struct flash_info spi_nor_ids[] = {
> > >>>>>>         { INFO("s25sl064p",  0x010216, 0x4d00,  64 * 1024, 128,
> > >>>>> SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ) },
> > >>>>>>         { INFO("s25fl256s0", 0x010219, 0x4d00, 256 * 1024, 128,
> > >>>>>> USE_CLSR)
> > >> },
> > >>>>>>         { INFO("s25fl256s1", 0x010219, 0x4d01,  64 * 1024, 512,
> > >>>>> SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ | USE_CLSR) },
> > >>>>>> -       { INFO6("s25fl512s",  0x010220, 0x4d0081, 256 * 1024, 256,
> > >>>>> SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ | USE_CLSR) },
> > >>>>>> +       { INFO6("s25fl512s",  0x010220, 0x4d0081, 256 * 1024,
> > >>>>>> + 256, SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ | USE_CLSR |
> > >>>>>> + SPI_NOR_4B_OPCODES) },
> > >>>>>
> > >>>>> I didn't find any diff b/w this with respect to v1 patch, seems
> > >>>>> like Vignesh commented some issue? any update on that.
> > >>>>
> > >>>> Hi Jagan, Vignesh,
> > >>>>
> > >>>> I had updated commit message.
> > >>>>
> > >>>> Wrt Vignesh's comment:
> > >>>> To me it seems not valid. This Flash can be used in extended 3-byte
> > >> addressing mode as well as 4-byte addressing mode.
> > >>>> Adding SPI_NOR_4B_OPCODE, will make use of 4-byte addressing mode
> > >> with CONFIG_SPI_FLASH_BAR being __not__ set.
> > >>>> By adding SPI_NOR_4B_OPCODES code flow will via
> > >> spi_nor_set_4byte_opcodes() in place of set_4byte().
> > >>>>
> > >>
> > >> This does not seem right. Here is the code snippet from spi-nor-
> > >> core.c::spi_nor_scan():
> > >>
> > >> #ifndef CONFIG_SPI_FLASH_BAR
> > >>                 /* enable 4-byte addressing if the device exceeds 16MiB */
> > >>                 nor->addr_width = 4;
> > >>                 if (JEDEC_MFR(info) == SNOR_MFR_SPANSION ||
> > >>                     info->flags & SPI_NOR_4B_OPCODES)
> > > Hi Vignesh,
> > >
> > > 1. It seems old, but at least one of the flash(spansion) on my NXP/Freescale
> > board reported manufacturing ID as 02h in place of 01h as result I had to
> > add this flags, I will try to trace that particular board. Reading the flow again
> > it seems this patch is not required due to presence of || operator as long
> > manufacturer ID is reported correctly.
> > > if (JEDEC_MFR(info) == SNOR_MFR_SPANSION ||
> > >                      info->flags & SPI_NOR_4B_OPCODES)
> >
> > So its just a quirky flash with different manf ID? If manuf ID reads different
> > then how does it match s25fl512s entry in the spi-nor-ids?
> >
> > > 2. The very first link on google [1] leads to an APP note from spansion
> > suggesting manufacturing id as 02h, is there a possibility of such flashes in
> > circulation, or am I referring something incorrect ? I will double check this
> > with spansion FAE.
> > > Snippet from APP note named: "AN98488 - Quick Guide to Common Flash
> > Interface"
> > >>>>>>
> > > The Cypress Manufacturer ID for flash devices is 0002h (historically
> > > the AMD ID is 0002h and the Fujitsu ID is 0004h; the former Spansion ID is
> > 0002h)."
> > > <<<<<
> >
> > Cypress seems to use different ID for CFI NOR flash (on Parallel NOR interface
> > or HyperBus interface). Thats a different standard (JEDEC CFI ID codes
> > https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.j
> > edec.org%2Fstandards-documents%2Fdocs%2Fjep-
> > 137b&data=02%7C01%7Cashish.kumar%40nxp.com%7Cd21e92a1fe4541
> > 8eae2608d70c7486b4%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7
> > C636991566928021371&sdata=1i7GEVXSIk2i5%2F%2FXuhXdan1%2BByRt
> > yNZrVltINAka1sI%3D&reserved=0)
> >
> > SPI NOR flashes from Cypress/Spansion reads 0x1 for Manufacturer ID.
> > This is based on JEDEC standard
> > https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.j
> > edec.org%2Fstandards-documents%2Fdocs%2Fjep-
> > 106ab&data=02%7C01%7Cashish.kumar%40nxp.com%7Cd21e92a1fe454
> > 18eae2608d70c7486b4%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%
> > 7C636991566928021371&sdata=OA1ivCTeCO%2BIQsYFEZc5dMxEcETSIIt9
> > yZu%2FU%2FWQBfI%3D&reserved=0
> >
> > > 3. s25fl064l, s25fl128l flash id has SPI_NOR_4B_OPCODES, what is the use
> > of this flag here then ?
> > >
> >
> > That was an overlook when those were added to Linux spi-nor code and
> > became part of U-Boot during syncing of framework.
> >
> > I am not saying that adding SPI_NOR_4B_OPCODES is wrong, because
> > Spansion flashes does support stateless 4 byte addressing opcodes. But I am
> > saying that it should not be needed in the first place (as you can see from
> > code snippets). If you ever need to add SPI_NOR_4B_OPCODES to spansion
> > flashes (with manf ID 0x1) then I think there is a bug somewhere in the code
> > which needs to be debugged and understood.
> Hi Vignesh ,
>
> Agreed.
> Should I send a negative patch to remove my patch for spansion flash.
> Or it will be simply drop from spi-master by Jagan.

Will drop anyway.