Re: [PATCH] soc: qcom: geni: shield ICC calls for ACPI boot

[Shawn Guo <shawn.guo@linaro.org>]

On Thu, Jan 14, 2021 at 12:17:23AM +0100, AngeloGioacchino Del Regno wrote:
> Il 28/12/20 14:56, Shawn Guo ha scritto:
> > Currently, GENI devices like i2c-qcom-geni fails to probe in ACPI boot,
> > if interconnect support is enabled.  That's because interconnect driver
> > only supports DT right now.  As interconnect is not necessarily required
> > for basic function of GENI devices, let's shield those ICC calls to get
> > GENI devices probe for ACPI boot.
> > 
> > Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
> > ---
> >   drivers/soc/qcom/qcom-geni-se.c | 15 +++++++++++++++
> >   1 file changed, 15 insertions(+)
> > 
> Hello!
> 
> To avoid developers booting on ACPI getting "strange slownesses" and
> possibly timeouts with no apparent reason, wouldn't it be a bit more proper
> and friendly to actually send a kernel message to advertise that there is
> *no interconnect support* and that this may lead to the aforementioned
> potential issues?

Thanks for the comment.

The commit 58ffbba6a399 ("soc: qcom: geni: Support for ICC voting")
was landed just recently, and we have been running those geni-se device
drivers without ICC voting for years.  I doubt it would have been the
case if missing ICC from any of those geni-se will cause any strange
slowness or timeout issues. 

There are only a limited number of drivers on Snapdragon that support
ACPI boot right now.  We are running it with distro installer, and
haven't seen any slowness or timeout.

In short, I prefer to add warnings that are really helpful rather than
just something noisy.

Shawn