From: Ian Campbell <ijc@hellion.org.uk>
Date: Wed, 29 Oct 2014 10:34:40 +0000
Subject: [U-Boot] [PATCH 1/2] exynos5250/arndale: Enable SATA/AHCI
 support.
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	<CALrBrZ0pdeJK80YxnJRKvT-ENCVU40BMY4GGinmVY7CDKKkj1Q@mail.gmail.com>
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On Sun, 2014-10-26 at 16:27 +0900, Minkyu Kang wrote:
> Dear Ian Campbell,
> 
> On 7 October 2014 22:56, Ian Campbell <ijc@hellion.org.uk> wrote:
>         From: Ian Campbell <ian.campbell@citrix.com>
>         
>         This is based on some old patches from the chromeos-v2011.12
>         branch of
>         http://git.chromium.org/chromiumos/third_party/u-boot.git by
>         Taylor Hutt.
>         Specifically:
>         
>         http://git.chromium.org/gitweb/?p=chromiumos/third_party/u-boot.git;a=commit;h=26f6c570b5deb37c52306920ae049203c68f014a
>             exynos: sata: on-board controller initialization
>             Signed-off-by: Taylor Hutt <thutt@chromium.org>
>         
>         http://git.chromium.org/gitweb/?p=chromiumos/third_party/u-boot.git;a=commit;h=d8cac5cf0b63df00d2d6ac7df814613e4b60b9d1
>             exynos: sata: Add sata_initialize() interface
>             Signed-off-by: Taylor Hutt <thutt@chromium.org>
>         
>         http://git.chromium.org/gitweb/?p=chromiumos/third_party/u-boot.git;a=commit;h=dd32462453d6328bc5770859d1b56501f7920d7d
>             exynos: sata: SATA self-configuration for when SATA device
>         is enabled
>             Signed-off-by: Taylor Hutt <thutt@chromium.org>
>         
>         As well as rebasing there have been some significant changes.
>         
>          - Drop support for smdk5250, which I don't own.
>          - Implement support for arndale, which I do.
>          - Since arndale has no need to frob a GPIO on SATA init drop
>         the associated
>            code.
>          - Initialise via the existing scsi_init hook rather than
>         introducing
>            sata_initialize, associated build system and
>         include/configs/*.h changes.
>          - Use set/clrbits in a bunch of places
>          - Add some #defines for some magic numbers.
>         
>         This relies on "ahci: Don't start command DMA engine before
>         buffers are set"
>         
>         NOTE: For some reason when running u-boot with this patch
>         Linux is unable to
>         correct probe devices. See the next patch for an attempt at a
>         hack/workaround.
>         Any ideas would be appreciated.
> 
> 
> So, is it RFC? or not?

This patch is, so far as I know, OK wrt the functionality it tries to
enable (i.e. sata access from u-boot), but there is a caveat wrt
launching Linux afterwards, which I obviously expect means it cannot be
applied as is. I have requested any help/ideas you may have. So, do you
have advice/ideas on the issue I raised?

> Why you tied up this RFC patch? ([U-Boot,2/2] HACK: arndale: deinit
> scsi before launching Linux)

I'm afraid I don't understand this question.

>         +void * const phy_ctrl = (void *)SATA_PHCTRL_APB;
>         +void * const phy_i2c_base = (void *)SATA_PHY_I2C_ABP;
> 
> 
> we don't allow direct access to the register.
> please refer to other driver.

There seem to be plenty of drivers in u-boot which use this pattern.
Perhaps you could be more specific about what you would like to be done
here?

[...]
> please remove blank line.

I'll fix up all the coding style issues before reposting.

Ian.