Re: [PATCH] ARM: dts: imx6sx-sdb: Remove cpufreq OPP override

[Fabio Estevam]

Hi Leonard,

On Tue, Apr 25, 2017 at 1:57 PM, Leonard Crestez
<leonard.crestez@xxxxxxx> wrote:
> The board file for imx6sx-dbg overrides cpufreq operating points to use
> higher voltages. This is done because the board has a shared rail for
> VDD_ARM_IN and VDD_SOC_IN and when using LDO bypass the shared voltage
> needs to be a value suitable for both ARM and SOC.
>
> This was introduced in:
>
> commit 54183bd7f766 ("ARM: imx6sx-sdb: add revb board and make it default")
>
> This only only applies to LDO bypass mode, a feature not present in
> upstream. When LDOs are enabled the effect is to use higher voltages than
> necesarry for no good reason.
>
> Setting these higher voltages can make some boards fail to boot with ugly
> semi-random crashes, reminiscent of memory corruption. These failures
> happen the first time the lowest idle state is used. Remove the OPP
> override in order to fix those crashes.
>
> Signed-off-by: Leonard Crestez <leonard.crestez@xxxxxxx>
>
> ---
> It's not clear exactly why the crashes happen. Perhaps waking up from idle
> draws more power than is available? Removing this override is a correct
> change anyway so maybe there is no need to investigate deeper.

Marek just sent a similar one a few minutes ago:
http://lists.infradead.org/pipermail/linux-arm-kernel/2017-April/503230.html