[U-Boot-Users] [PATCH 1/2] AT572D940HF-EB Support v2 (SDHC support part 1)

[Haavard Skinnemoen]

On Thu, 12 Jun 2008 16:14:56 +0200
"Antonio R. Costa" <costa.antonior at gmail.com> wrote:

> This patch add support for SD/SDHC cards to AT572D940HF-EB
> and more generally is a proposal for all Atmel chips.
> Dued to that I placed atmel_mci.c under the board directory.

It's a bit hard to see what your proposal is all about when you create
a new file instead of modifying the exising one...

> The implementation of the CSD interpretation has been re-worked
> completely. Bit fields are not portable so there were replaced by
> a vector of 4 32-bit words and some macros.
> 
> Probing process follow the schema from SD spec 2.0:
>   sdhc --> sd --> mmc
> 
> Introduced IF_TYPE_SDHC to distinguish between SD and SDHC.
> Maybe this is not the best method since struct block_dev_descr.priv
> could point to a structure describing card properties but it was
> the quickest one and I had no time to spend.
> 
> Tested SD:
>   - Mediacom    512 MB (spec 1.0)  bare FAT16 no partition table
>   - Kingstone     1 GB (spec 1.0)  1 FAT16
>   - Trascend      2 GB (spec 1.01) 1 FAT16
>   - TakeMS        4 GB (spec 1.10) 1 FAT16
> 
> Tested SDHC:
>   - Peak          8 GB (spec 2.0)  1 FAT32

Ideally, this sort of thing should go into a common MMC layer for
u-boot. But at the very least, we should use the same driver on all
chips that feature the same hardware (other AT91 chips and AVR32).

So how about we start by introducing a new drivers/mmc directory and
move the existing AVR32 driver there? After that, you can apply your
changes to it and send a patch which clearly shows the differences from
the old code. Don't worry about breaking AVR32 -- I'll help you test it
before it gets merged upstream.

Then, after that, if someone feels up to the task, he can gather all
the different pieces together from the existing drivers and create a
common MMC layer.

Does that sound like a good plan to you?

Haavard