MIME-Version: 1.0
Date:   Mon, 13 Mar 2023 11:39:00 +0100
From:   Michael Walle <michael@walle.cc>
To:     Miquel Raynal <miquel.raynal@bootlin.com>
Cc:     Luke He <sixuerain@gmail.com>, tudor.ambarus@linaro.org,
        pratyush@kernel.org, richard@nod.at, vigneshr@ti.com,
        linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mtd: spi-nor: Add support for XMC XM25QH256C / XM25QU256C
 / XM25QH512C / XM25QU512C site: https://www.xmcwh.com/site/product#
In-Reply-To: <20230313113304.1611638d@xps-13>
References: <20230313100153.15441-1-sixuerain@gmail.com>
 <d553beb1c6e38eac748d0b6b62bcd335@walle.cc> <20230313113304.1611638d@xps-13>
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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 :)

-michael