Re: [PATCH v5 15/17] qcom: llcc/edac: Fix the base address used for accessing LLCC banks

From: Manivannan Sadhasivam
Date: Sat Jan 14 2023 - 23:03:34 EST


On Sat, Jan 14, 2023 at 02:27:50PM +0100, Borislav Petkov wrote:
> On Wed, Dec 28, 2022 at 02:10:26PM +0530, Manivannan Sadhasivam wrote:
> > The Qualcomm LLCC/EDAC drivers were using a fixed register stride for
> > accessing the (Control and Status Registers) CSRs of each LLCC bank.
> > This stride only works for some SoCs like SDM845 for which driver
> > support was initially added.
> >
> > But the later SoCs use different register stride that vary between the
> > banks with holes in-between. So it is not possible to use a single register
> > stride for accessing the CSRs of each bank. By doing so could result in a
> > crash.
>
> If this patch fixes a crash, then it should be
>
> Cc: <stable@xxxxxxxxxx>
>
> If there are prerequisites to it, they should be CC:stable too.
>

That's what I did in previous revision but then Krzysztof reported that
backporting would break old DTs. See discussion on v2:
https://lore.kernel.org/lkml/20221212123311.146261-1-manivannan.sadhasivam@xxxxxxxxxx/

Thanks,
Mani

> So looking at the urgent stuff: patches 1, 3, I'm thinking I can take them
> through the EDAC tree and send them to Linus now, after you've addressed the
> review comments.
>
> This one can go through some other tree, I presume, but since it fixes a crash
> it should go in now too...
>
> > For fixing this issue, let's obtain the base address of each LLCC bank from
> > devicetree and get rid of the fixed stride. This also means, we no longer
>
> Please use passive voice in your commit message: no "we" or "I", etc,
> and describe your changes in imperative mood.
>
> Personal pronouns are ambiguous in text, especially with so many
> parties/companies/etc developing the kernel so let's avoid them please.
>
> > need to rely on reg-names property and get the base addresses using index.
> >
> > First index is LLCC bank 0 and last index is LLCC broadcast. If the SoC
> > supports more than one bank, then those needs to be defined in devicetree
>
> s/needs/need/
>
> > for index from 1..N-1.
> >
> > Reported-by: Parikshit Pareek <quic_ppareek@xxxxxxxxxxx>
> > Tested-by: Luca Weiss <luca.weiss@xxxxxxxxxxxxx>
> > Tested-by: Steev Klimaszewski <steev@xxxxxxxx> # Thinkpad X13s
> > Tested-by: Andrew Halaney <ahalaney@xxxxxxxxxx> # sa8540p-ride
> > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
>
> With the above addressed, for the EDAC bits:
>
> Reviewed-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
>
> Thx.
>
> --
> Regards/Gruss,
> Boris.
>
> https://people.kernel.org/tglx/notes-about-netiquette

--
மணிவண்ணன் சதாசிவம்