[PATCH] mtd: spi-nor: boya: add support for boya by25q128as
George Brooke
figgyc at figgyc.uk
Tue Apr 6 17:11:28 BST 2021
Hi again Tudor,
I've been busy with other things but I sat down today to have a
hard
look into this.
Tudor.Ambarus at microchip.com writes:
> On 2/13/21 7:10 PM, George Brooke wrote:
>> EXTERNAL EMAIL: Do not click links or open attachments unless
>> you know the content is safe
>>
>> Hello Tudor,
>
> Hi, George,
>
> Sorry for the long delay :(. I added in To: Chris and Andreas,
> they
> encounter a similar problem with other vendors.
>
>>
>> Tudor.Ambarus at microchip.com writes:
>>
>>> Hi, George,
>>>
>>> On 2/7/21 2:30 PM, George Brooke wrote:
>>>> EXTERNAL EMAIL: Do not click links or open attachments unless
>>>> you know the content is safe
>>>>
>>>> Adds support for the Boya Microelectronics BY25Q128AS 128
>>>> Mbit
>>>> flash.
>>>> I tested this on the Creality WB-01 embedded device which
>>>> uses
>>>> this,
>>>> although that was with OpenWrt which is still using 5.4 so I
>>>> had to
>>>> do a bit of porting work. Don't see how that would make much
>>>> of
>>>> a
>>>> difference though.
>>>>
>>>> Signed-off-by: George Brooke <figgyc at figgyc.uk>
>>>> ---
>>>> drivers/mtd/spi-nor/Makefile | 1 +
>>>> drivers/mtd/spi-nor/boya.c | 23 +++++++++++++++++++++++
>>>> drivers/mtd/spi-nor/core.c | 1 +
>>>> drivers/mtd/spi-nor/core.h | 1 +
>>>> 4 files changed, 26 insertions(+)
>>>> create mode 100644 drivers/mtd/spi-nor/boya.c
>>>>
>>>> diff --git a/drivers/mtd/spi-nor/Makefile
>>>> b/drivers/mtd/spi-nor/Makefile
>>>> index 653923896205..7d1551fbfbaa 100644
>>>> --- a/drivers/mtd/spi-nor/Makefile
>>>> +++ b/drivers/mtd/spi-nor/Makefile
>>>> @@ -2,6 +2,7 @@
>>>>
>>>> spi-nor-objs := core.o sfdp.o
>>>> spi-nor-objs += atmel.o
>>>> +spi-nor-objs += boya.o
>>>> spi-nor-objs += catalyst.o
>>>> spi-nor-objs += eon.o
>>>> spi-nor-objs += esmt.o
>>>> diff --git a/drivers/mtd/spi-nor/boya.c
>>>> b/drivers/mtd/spi-nor/boya.c
>>>> new file mode 100644
>>>> index 000000000000..014b0087048a
>>>> --- /dev/null
>>>> +++ b/drivers/mtd/spi-nor/boya.c
>>>> @@ -0,0 +1,23 @@
>>>> +// SPDX-License-Identifier: GPL-2.0
>>>> +/*
>>>> + * Copyright (C) 2005, Intec Automation Inc.
>>>> + * Copyright (C) 2014, Freescale Semiconductor, Inc.
>>>> + */
>>>> +
>>>> +#include <linux/mtd/spi-nor.h>
>>>> +
>>>> +#include "core.h"
>>>> +
>>>> +static const struct flash_info boya_parts[] = {
>>>> + /* Boya */
>>>> + { "by25q128as", INFO(0x684018, 0, 64 * 1024, 256,
>>>
>>> The manufacturer’s identification code is defined by one or
>>> more
>>> eight (8) bit fields each consisting of seven (7) data bits
>>> plus
>>> one (1)
>>> odd parity bit. It is a single field limiting the possible
>>> number of
>>> vendors to 126. To expand the maximum number of identification
>>> codes a
>>> continuation scheme has been defined.
>>>
>>> According to JEP106BA, the manufacturer ID for Boya should be
>>> preceded by
>>> eight continuation codes. So I would expect the manufacturer
>>> ID
>>> for this
>>> flash to be: 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f,
>>> 0x68.
>>>
>>> Without the continuation codes, we will have collisions
>>> between
>>> manufacturer IDs, Convex Computer being an example.
>>>
>>> I see that the datasheet [1] for this flash doesn't specify
>>> anything
>>> about the continuation codes, so I suspect that Boya just got
>>> it
>>> wrong.
>>
>> It appears you are right. I thought it would be the best idea
>> to
>> actually
>> interact with the flash chip and read its responses, so I found
>> a
>> tool
>> called spincl [2] to send some commands to it with a Raspberry
>> Pi:
>>
>> $ spincl -ib -m0 -c0 -s0 -p0 6 0x90
>> 0x00 0x00 0x00 0x00 0x68 0x17
>
> I wasn't aware of the 0x90 command, it's not in the
> include/linux/mtd/spi-nor.h either. Do you know what 0x17 means?
>
0x90 (and 0x92 for dual spi, 0x94 for quad spi) seems to be in
Winbond
chips [5], Boya chips [1], the ESMT chip [4] and an XMC chip [6],
from
the datasheets I've looked at so far.
They all seem to implement it in the same way: a "24 bit address"
which
is just a flag for device ID first or manufacturer ID first, then
output
one and the other repeatedly.
It isn't in the Micron MT25QU128ABA [7] or the Atmel AT25FS010 [8]
at
the very least, so it's not universal.
Interestingly the description of 0x90 in the XMC datasheet is
suspiciously similar to the one in the Winbond datasheet.
0x17 is just listed in the BY25Q128AS datasheet in the "ID
Definition
Table"; I'm fairly sure it's just arbitrarily decided by the
vendor for
each chip type.
>> $ spincl -ib -m0 -c0 -s0 -p0 4 0x9F
>> 0x00 0x68 0x40 0x18
>> and indeed there doesn't seem to be any continuation codes.
>>
>>> We'll have to check other datasheets from Boya and see if they
>>> got
>>> their manufacturer ID wrong for all their flashes. We'll have
>>> to
>>> add
>>
>> The BY25Q64AS [3] appears to be described similarly.
>>
>>> some fixup mechanism for the manufacturers ID handling, in
>>> order
>>> to
>>> avoid collisions with other manufacturers IDs.
>>
>> I looked into this a bit more, and what I'm realising is that
>> I'm
>> not sure if
>> there even is any mechanism to deliver the continuation codes
>> within the
>> base SPI-NOR standard? Take esmt.c: the f25l32qa has a device
>> id
>> 0x8c4116.
>> JEP106BA attribytes 8c to Monolithic Memories in the first
>> bank,
>> while
>> Elite Flash Storage (presumably an alias of ESMT) should be
>> identifying
>> as 0x7f, 0x7f, 0x7f, 0x8c. Its datasheet [4] appears to be
>> equally
>> sparse on
>> detail. To my untrained eye, this seems to be the exact same
>> situation we
>> find ourselves in here. (You probably know a lot more about
>> this
>> then I do -
>> if I'm wrong do point it out!)
>
> I don't, but on a quick search I see that Elite Flash Storage
> may be
> an alias for ESMT, so probably you're right. I wasn't aware of
> the
> esmt problem, thanks for pointing it out.
>
>>
>> That said I can't seem to find any formalised definition of
>> what
>> the 0x90
>> "manufacturer and device ID" command is actually supposed to do
>> in
>> the case of
>> a manufacturer ID that isn't in the first bank. Likewise with
>> 0x9f
>> "JEDEC ID".
>
> I don't know if there's a standardized definition. Maybe we can
> shuffle
> through datasheets and check what manufacturers are saying about
> this.
>
I decided to look at all the manufacturer IDs currently in spi-nor
to
see if there is any consensus on the handling of device ID
commands.
In terms of manufacturer ID banks:
- Catalyst and Everspin are non-JEDEC
- Atmel, Fujitsu, Macronix, SST, Micron/ST, Spansion/Cypress,
Winbond
use manufacturer codes in the first bank, so no special handling
is
expected
- EON, ESMT, GigaDevice, ISSI and XMC are all in banks other than
the
first bank, so basically the same situation as I mentioned with
ESMT
in the previous email.
There's two especially interesting cases:
- Xilinx S3AN flashes use 0x1f, despite 0x1f bank 1 is
Atmel/Adesto.
In fact, 3S700AN has device ID 0x1f2500 which is collides with
Atmel
at45db081d, for example. I did some digging and its user guide
[10] says
system flash is "architecturally similar to the Adesto DataFlash
SPI
Flash memories" of which it shares ID numbers, so this is not a
collision but just the IP is licensed and they didn't change the
ID.
In fact the AT45DB081D also has [11] the strange 264-byte pages
option
in the Xilinx driver, so they might actually be functionally
identical.
- XMC flashes start 0x20. XMC has 0x20 in bank 10, but 0x20 bank 1
is
actually owned by Micron/ST who also make spi-nor flash chips.
There
don't seem to be any direct ID collisions yet though thankfully.
As a result I was hoping XMC chips may have some sort of
continuation
code handling but they don't seem to.
For instance XM25QH64A [6]: the datasheet does specify fairly
clearly
that the manufacturer ID is only one byte in both 0x90 and 0x9f.
I think this is just an unfortunate coincidence and not a
relabeling
since Micron chips don't have 0x90.
It seems like every 0x9f implementation I have looked at only
outputs the last byte of the manufacturer ID code, no
continuations.
The AT45DB081D datasheet does actually mention the existence of
JEP106
continuation codes but 0x1f is in the first bank so they do not
actually
exist on that device.
>> Do you know of any flashes made by companies not in the first
>> bank
>> that
>> identify themselves correctly?
>
> No, I've worked only with flashes that have their ID in the
> first bank.
>
>>
>> As far as I can tell the only proper method available is in
>> SFDP,
>> where the
>> Parameter ID of a vendor specific table would be the bank
>> number
>> in the MSB
>> and the actual manufacturer code in the LSB. However, this is a
>> very
>> over-engineered solution, wouldn't work on devices with no
>> vendor
>> specific
>> tables, and in this case, I couldn't even get the SFDP table to
>> read out of
>> the by25q128as at all:
>> $ spincl -ib -m0 -c0 -s0 -p0 32 0x5A
>> 0x00 0x00 0x00 0x00 0x00 0xff 0xff 0xff 0xff 0xff 0xff 0xff
>> 0xff
>> 0xff 0xff ...
>> (This may very well be a peculiarity of the way I'm accessing
>> it,
>> but in any
>> case I don't think this fix would be a very good idea.)
>
> yeah, maybe the tool is broken, because I see that the SFDP
> table
> is defined in the datasheet. The manufacturer specific table
> identification looks broken too. MSB should have been 0x08 and
> LSB
> 0x68, whereas they have for MSB 0xff and LSB 0x0b? We can hack
>
I think you're confusing my chip with the XTX chip Chris is
looking at.
It [9] has a 0xff 0x0b table. I can't see the SFDP table in my
datasheet?
> the sfdp read to dump the tables. Or use Michael's sfdp dump
> sysfs
> patches:
>
> https://patchwork.ozlabs.org/project/linux-mtd/list/?series=235475
>
Good idea, I can try and do some device tree so I can connect to
my mtd
chip on a raspberry pi on a recent kernel to see if I can run
Michael's
patches. That'd take me a while though so I'll get back to you on
that.
Not that I'm particularly sure it would help our situation very
much.
I also see Chris has dumped his while I was writing this email and
it
does seem to match with the XTX datasheet.
>>
>> I'm not sure what would actually make a good fixup in this
>> scenario. We'd need
>> something that could differentiate a Boya chip from any other
>> hypothetical
>> 0x68 manufacturer flash.
>> Maybe even the missing SFDP output would make a good detection
>> routine, but
>> that would need testing with a better SPI inspection method and
>> across multiple
>> flash chips because I doubt that's intentional - surely if SFDP
>> didn't work it
>> would just not be described in the datasheet. Probably better
>> to
>> think of
>> something other than that though.
>>
>
> The first collision between a flash from the first bank and any
> other
> flashes from the rest of the banks can be avoided if we move all
> the
> manufacturers with continuation codes at the end of the
> manufacturers
> array, so that at the flash detection code they are treated as
> last.
>
> Collision between flashes with continuation codes is more
> difficult
> to solve and would require differentiation at run-time. Will
> have to
> check jesd216 to see if there's other unique method to identify
> a flash.
> Can you check it?
>
I've read through the entirety of JESD216D.01 and JESD251A and I'm
pretty sure SFDP vendor-specific tables are the only place in the
entire
standard where manufacturer ID codes are mentioned at all.
It seems kind of crazy to me that our main mechanism of flash ID
isn't
standardised anywhere, despite the fact that almost every chip
supports
it in a similar way. I really feel like I must be missing
something but
at this point I wouldn't know where else to look.
I am led to the conclusion that so far, the common solution to
JEP106
continuation codes and banks is to pretend they don't exist and
hope
nobody has any collisions. That basically just leaves us to
distinguishing between manufacturers using unique commands.
0x90 might be a good command for that? It's semi vendor specific
and has
some sort of unique system, but it still doesn't properly
implement
JEDEC manufacturer IDs so it definitely doesn't rule out the
possibility
of collision, and it won't work universally.
The SFDP vendor-specific tables solution also technically exists
but the
XTX chip shows that's probably not the best idea. Overall this
doesn't
seem very ideal and I'm not confident on what the best solution
is.
Thanks,
figgyc
[5]
https://cdn.datasheetspdf.com/pdf-down/W/2/5/W25Q128BV_Winbond.pdf
[6] http://www.xmcwh.com/Uploads/2018-02-05/5a77d2cf60e04.pdf
[7]
https://media-www.micron.com/-/media/client/global/documents/products/data-sheet/nor-flash/serial-nor/mt25q/die-rev-a/mt25q_qlhs_u_128_aba_0.pdf
[8]
https://media.digikey.com/pdf/Data%20Sheets/Atmel%20PDFs/AT25FS010.pdf
[9]
https://datasheet.lcsc.com/szlcsc/2005251034_XTX-XT25F128BSSIGT_C558844.pdf
[10]
https://www.xilinx.com/support/documentation/user_guides/ug333.pdf
[11] https://www.adestotech.com/wp-content/uploads/doc3596.pdf
>
> Cheers,
> ta
>
>> Thanks,
>> figgyc
>>
>> [2] https://github.com/CrosseyeJack/spincl
>> [3]
>> https://datasheet.lcsc.com/szlcsc/1904091402_BOYAMICRO-BY25Q64ASSIG_C383793.pdf
>> [4]
>> https://www.esmt.com.tw/upload/pdf/ESMT/datasheets/F25L32QA.pdf
>>
>>>
>>> Cheers,
>>> ta
>>>
>>> [1]
>>> https://datasheet.lcsc.com/szlcsc/1904091402_BOYAMICRO-BY25Q128ASSIG_C383794.pdf
>>>
>>>> + SECT_4K | SPI_NOR_DUAL_READ |
>>>> SPI_NOR_QUAD_READ |
>>>> + SPI_NOR_HAS_LOCK | SPI_NOR_HAS_TB)
>>>> + },
>>>> +};
>>>> +
>>>> +const struct spi_nor_manufacturer spi_nor_boya = {
>>>> + .name = "boya",
>>>> + .parts = boya_parts,
>>>> + .nparts = ARRAY_SIZE(boya_parts),
>>>> +};
>>>> diff --git a/drivers/mtd/spi-nor/core.c
>>>> b/drivers/mtd/spi-nor/core.c
>>>> index 20df44b753da..4d0d003e9c3f 100644
>>>> --- a/drivers/mtd/spi-nor/core.c
>>>> +++ b/drivers/mtd/spi-nor/core.c
>>>> @@ -2160,6 +2160,7 @@ int spi_nor_sr2_bit7_quad_enable(struct
>>>> spi_nor *nor)
>>>>
>>>> static const struct spi_nor_manufacturer *manufacturers[] =
>>>> {
>>>> &spi_nor_atmel,
>>>> + &spi_nor_boya,
>>>> &spi_nor_catalyst,
>>>> &spi_nor_eon,
>>>> &spi_nor_esmt,
>>>> diff --git a/drivers/mtd/spi-nor/core.h
>>>> b/drivers/mtd/spi-nor/core.h
>>>> index d631ee299de3..d5ed5217228b 100644
>>>> --- a/drivers/mtd/spi-nor/core.h
>>>> +++ b/drivers/mtd/spi-nor/core.h
>>>> @@ -409,6 +409,7 @@ struct spi_nor_manufacturer {
>>>>
>>>> /* Manufacturer drivers. */
>>>> extern const struct spi_nor_manufacturer spi_nor_atmel;
>>>> +extern const struct spi_nor_manufacturer spi_nor_boya;
>>>> extern const struct spi_nor_manufacturer spi_nor_catalyst;
>>>> extern const struct spi_nor_manufacturer spi_nor_eon;
>>>> extern const struct spi_nor_manufacturer spi_nor_esmt;
>>>> --
>>>> 2.30.0
>>>>
>
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