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From: Stephen Warren <swarren@wwwdotorg.org>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH] RFC: tegra: Avoid using I2C prior to relocation
Date: Wed, 07 Aug 2013 10:20:01 -0600	[thread overview]
Message-ID: <520273B1.30200@wwwdotorg.org> (raw)
In-Reply-To: <1375854747-3621-1-git-send-email-sjg@chromium.org>

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@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.

  reply	other threads:[~2013-08-07 16:20 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-08-07  5:52 [U-Boot] [PATCH] RFC: tegra: Avoid using I2C prior to relocation Simon Glass
2013-08-07 16:20 ` Stephen Warren [this message]
2013-08-07 21:03   ` Simon Glass
2013-08-09 23:17   ` Stephen Warren
2013-08-10  4:03     ` Simon Glass
2013-08-11  1:21       ` Tom Warren
2013-08-13 19:34         ` Simon Glass
2013-08-13 19:42           ` Stephen Warren
2013-08-13 21:12   ` Tom Rini
2013-08-14 15:59     ` Stephen Warren
2013-08-14 16:02       ` Simon Glass

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