Message-ID: <939c029f-6679-b364-531c-bf0193135ffd@linaro.org>
Date:   Mon, 13 Mar 2023 11:23:13 +0000
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Subject: Re: [PATCH] mtd: spi-nor: Add support for XMC XM25QH256C / XM25QU256C
 / XM25QH512C / XM25QU512C site: https://www.xmcwh.com/site/product#
Content-Language: en-US
To:     Michael Walle <michael@walle.cc>,
        Miquel Raynal <miquel.raynal@bootlin.com>
Cc:     Luke He <sixuerain@gmail.com>, pratyush@kernel.org, richard@nod.at,
        vigneshr@ti.com, linux-mtd@lists.infradead.org,
        linux-kernel@vger.kernel.org
References: <20230313100153.15441-1-sixuerain@gmail.com>
 <d553beb1c6e38eac748d0b6b62bcd335@walle.cc> <20230313113304.1611638d@xps-13>
 <17d46633869f64e029e065693e341e3b@walle.cc>
From:   Tudor Ambarus <tudor.ambarus@linaro.org>
In-Reply-To: <17d46633869f64e029e065693e341e3b@walle.cc>
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On 3/13/23 10:39, Michael Walle wrote:
> Am 2023-03-13 11:33, schrieb Miquel Raynal:
>> Hi Michael,
>>
>> michael@walle.cc wrote on Mon, 13 Mar 2023 11:08:15 +0100:
>>
>>> Hi,
>>>
>>> please have a look at Documentation/process/submitting-patches.rst
>>> how to properly format patches. But also see below.
>>>
>>> Am 2023-03-13 11:01, schrieb Luke He:
>>> > Signed-off-by: Luke He <sixuerain@gmail.com>
>>> > ---
>>> >  drivers/mtd/spi-nor/xmc.c | 12 ++++++++++++
>>> >  1 file changed, 12 insertions(+)
>>> >
>>> > diff --git a/drivers/mtd/spi-nor/xmc.c b/drivers/mtd/spi-nor/xmc.c
>>> > index 051411e86339..6db01b80237f 100644
>>> > --- a/drivers/mtd/spi-nor/xmc.c
>>> > +++ b/drivers/mtd/spi-nor/xmc.c
>>> > @@ -16,6 +16,18 @@ static const struct flash_info xmc_nor_parts[] = {
>>> >      { "XM25QH128A", INFO(0x207018, 0, 64 * 1024, 256)
>>> >          NO_SFDP_FLAGS(SECT_4K | SPI_NOR_DUAL_READ |
>>> >                    SPI_NOR_QUAD_READ) },
>>> > +    { "XM25QH256C", INFO(0x204019, 0, 64 * 1024, 512)
>>> > +        NO_SFDP_FLAGS(SECT_4K | SPI_NOR_DUAL_READ |
>>> > +                  SPI_NOR_QUAD_READ | SPI_NOR_4B_OPCODES) },
>>> > +    { "XM25QU256C", INFO(0x204119, 0, 64 * 1024, 512)
>>> > +        NO_SFDP_FLAGS(SECT_4K | SPI_NOR_DUAL_READ |
>>> > +                 SPI_NOR_QUAD_READ | SPI_NOR_4B_OPCODES) },
>>> > +    { "XM25QH512C", INFO(0x204020, 0, 64 * 1024, 1024)
>>> > +        NO_SFDP_FLAGS(SECT_4K | SPI_NOR_DUAL_READ |
>>> > +                 SPI_NOR_QUAD_READ | SPI_NOR_4B_OPCODES) },
>>> > +    { "XM25QU512C", INFO(0x204120, 0, 64 * 1024, 1024)
>>> > +        NO_SFDP_FLAGS(SECT_4K | SPI_NOR_DUAL_READ |
>>> > +                 SPI_NOR_QUAD_READ | SPI_NOR_4B_OPCODES) }
>>>
>>> I've just looked at XM25QH256C [1], but I suspect all of these
>>> flashes supports SFDP, therefore you shouldn't use the NO_SFDP_FLAGS.
>>
>> I didn't check, do we have a kdoc or something like that which explains
>> what flags to use and when?
> 
> https://elixir.bootlin.com/linux/v6.3-rc2/source/drivers/mtd/spi-nor/core.h#L429
> 
> What's missing is still some overview document when and how to add a new
> entry to our database. /me looks in Tudors direction :)
> 

Right, the code comments should help. I've been planning to do the
documentation, even started it few months ago, but I'm still behind with
some patch reviews, including Miquel's, so the documentation has to
wait. I'm doing this in my spare time, so I'll stop giving estimates.

Cheers,
ta