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Date:   Fri, 21 Jul 2023 16:32:49 +0800
From:   Ming Lei <ming.lei@redhat.com>
To:     Daniel Golle <daniel@makrotopia.org>
Cc:     Jens Axboe <axboe@kernel.dk>, Ulf Hansson <ulf.hansson@linaro.org>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
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        ming.lei@redhat.com
Subject: Re: [RFC PATCH 0/6] nvmem: add block device NVMEM provider
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On Wed, Jul 19, 2023 at 11:01:14PM +0100, Daniel Golle wrote:
> On embedded devices using an eMMC it is common that one or more (hw/sw)
> partitions on the eMMC are used to store MAC addresses and Wi-Fi
> calibration EEPROM data.
> 
> Implement an NVMEM provider backed by block devices as typically the
> NVMEM framework is used to have kernel drivers read and use binary data
> from EEPROMs, efuses, flash memory (MTD), ...
> 
> In order to be able to reference hardware partitions on an eMMC, add code
> to bind each hardware partition to a specific firmware subnode.
> 
> This series is meant to open the discussion on how exactly the device tree
> schema for block devices and partitions may look like, and even if using
> the block layer to back the NVMEM device is at all the way to go -- to me
> it seemed to be a good solution because it will be reuable e.g. for NVMe.

Just wondering why you don't use request_firmware() in drivers which consume
the data, then the logic can be moved out of kernel, and you needn't to deal
with device tree & block device.

Or Android doesn't support udev and initrd?


Thanks,
Ming