[U-Boot] [PATCH] RFC: tegra: Avoid using I2C prior to relocation

From: Tom Warren <TWarren@nvidia.com>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH] RFC: tegra: Avoid using I2C prior to relocation
Date: Sat, 10 Aug 2013 18:21:30 -0700	[thread overview]
Message-ID: <5FBF8E85CA34454794F0F7ECBA79798F37AF25669A@HQMAIL04.nvidia.com> (raw)
In-Reply-To: <CAPnjgZ0hbmVWG7zZzth0tHyv2naK9=fNn_44TDFn+mLziUQrPA@mail.gmail.com>

Simon,

From: sjg@google.com [mailto:sjg at google.com] On Behalf Of Simon Glass
Sent: Friday, August 09, 2013 9:04 PM
To: Stephen Warren
Cc: U-Boot Mailing List; Tom Warren; Stephen Warren; trini at ti.com
Subject: Re: [PATCH] RFC: tegra: Avoid using I2C prior to relocation

+Tom Rini

Hi Stephen,

On Fri, Aug 9, 2013 at 5:17 PM, Stephen Warren <swarren at wwwdotorg.org<mailto:swarren@wwwdotorg.org>> wrote:
On 08/07/2013 10:20 AM, Stephen Warren wrote:
> On 08/06/2013 11:52 PM, Simon Glass wrote:
>> Tegra recently moved to the new I2C framework, which sets up I2C prior to
>> relocation, and prior to calling i2c_init_board(). This causes a crash on
>> Tegra boards.
>>
>> note:
>>
>> There are many ways to fix this. I believe this is one. It disables i2c_init()
>> until relocation is complete. I have been unable to test it so far due to
>> problems getting my Seaboard to work. I will try another Tegra board, but
>> send this for comment in the meantime.
>
> Tested-by: Stephen Warren <swarren at nvidia.com<mailto:swarren@nvidia.com>>
>
> (On Beaver and Dalmore, tested booting to U-Boot command prompt followed
> by "i2c dev 0; i2c probe")
>
> Note: I believe this is an enormous hack that hacks around the problem
> of dynamic device initialization just not being well thought out
> relative to the restrictions of U-Boot's various boot stages. I'd still
> prefer an outright revert of the broken code.
>
> In other words, tegra_i2c_init() simply shouldn't be called at the wrong
> time; it shouldn't have to handle being called at the wrong time and
> null itself out when that happens.
>
> However, if this is what it takes to get U-Boot working again, then
> let's apply it ASAP.
This doesn't seem to have been applied yet. Are you expecting this to go
through the main U-boot Tree, I2C tree, or Tegra tree? I just noticed
that you only CC'd the Tegra maintainer...

I put tegra: on the front expecting it to go that way, but it doesn't matter. Also your comments did not exactly represent a glowing recommendation.
[Tom] It's still marked RFC - doesn't that have to go away before anyone can pick it up / apply it?

Tom (Rini) are you willing to pick this up as a bug fix please?

Regards,
Simon

--
nvpublic