Re: [PATCH] clk: qcom: gcc-ipq6018: add QUP6 I2C clock

From: Kathiravan Thirumoorthy
Date: Wed Oct 25 2023 - 04:42:09 EST




On 10/21/2023 5:27 PM, Robert Marko wrote:
On Fri, 20 Oct 2023 at 08:40, Kathiravan Thirumoorthy
<quic_kathirav@xxxxxxxxxxx> wrote:


On 10/19/2023 7:53 PM, Robert Marko wrote:
On Thu, 19 Oct 2023 at 08:46, Kathiravan Thirumoorthy
<quic_kathirav@xxxxxxxxxxx> wrote:

On 10/19/2023 1:59 AM, Konrad Dybcio wrote:

On 10/15/23 18:20, Robert Marko wrote:
QUP6 I2C clock is listed in the dt bindings but it was never included in
the GCC driver.
So lets add support for it, its intentionally marked to never be
disabled
as its somehow affecting DVFS and if disabled it sometimes crashes the
board.

Signed-off-by: Robert Marko <robimarko@xxxxxxxxx>
---
Bjorn, would you be able to get an idea of what could be sitting
on that bus?

Or maybe the IPQ folks could know?

Konrad / Robert,

Similar to IPQ9574, RPM needs this clock to communicate with PMIC over
I2C interface. Discussion happened here[1] is pretty much applicable to
IPQ6018 as well. Based on previous experience, we may need to document
the reason for CLK_IGNORE_UNUSED in driver as well. Nevertheless,

Reviewed-by: Kathiravan Thirumoorthy <quic_kathirav@xxxxxxxxxxx>
Thanks for the explanation, it makes sense as I used to control the
MP5496 directly
via I2C.

Is it possible to disable RPM so it doesn't conflict and just use the
full MP5496 driver instead?
I find the RPM quite limiting as there is no way to actually retrieve
the current-voltage.


Robert, checked with the team and currently we don't have any option to
disable the RPM as such.

Thanks for checking.

BTW, is there any information you could share on the USB GDSC-s?
I tried converting them to GDSC-s like IPQ8074 has, but it seems that
they have different features.
It would be great to use proper GSDC support instead of manually
setting bits during GCC probe.


Could you please explain the issue which you are facing? Based on quick look at the HW documentation, seems there is no difference between IPQ8074 and IPQ6018 GDSC-s.

Thanks,