MIME-Version: 1.0
Date:   Mon, 13 Mar 2023 11:08:15 +0100
From:   Michael Walle <michael@walle.cc>
To:     Luke He <sixuerain@gmail.com>
Cc:     tudor.ambarus@linaro.org, pratyush@kernel.org,
        miquel.raynal@bootlin.com, 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: <20230313100153.15441-1-sixuerain@gmail.com>
References: <20230313100153.15441-1-sixuerain@gmail.com>
User-Agent: Roundcube Webmail/1.4.13
Message-ID: <d553beb1c6e38eac748d0b6b62bcd335@walle.cc>
Content-Type: text/plain; charset=US-ASCII;
 format=flowed
Content-Transfer-Encoding: 7bit
Precedence: bulk

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.
Then, without any additional flags, there is no need for an entry
at all, because it should be coverered by the "generic spi-nor"
driver [2].

-michael

[1] https://www.xmcwh.com/uploads/198/XM25QH256C_Ver1.8.pdf
[2] 
https://elixir.bootlin.com/linux/v6.3-rc2/source/drivers/mtd/spi-nor/core.c#L1637