On 11/1/2024 5:40 PM, Will Deacon wrote:
On Wed, Oct 30, 2024 at 05:00:13PM +0530, Bibek Kumar Patro wrote:
On 10/29/2024 6:17 PM, Will Deacon wrote:
On Fri, Oct 25, 2024 at 07:51:22PM +0530, Bibek Kumar Patro wrote:
On 10/24/2024 6:22 PM, Will Deacon wrote:
On Tue, Oct 08, 2024 at 06:24:06PM +0530, Bibek Kumar Patro wrote:
If you want to gate the errata workarounds on policy, then please follow
what we do for the CPU: add a Kconfig option (e.g.
ARM_SMMU_WORKAROUND_BROKEN_CPRE) which defaults to "on" (assuming that
the relevant errata aren't all "rare") and update silicon-errata.rst
accordingly.
Then you can choose to disable them in your .config if you're happy to
pick up the pieces.
This seems to be a good idea to me . I am thinking of this approach based on
your suggestion,
i.e. we can bind the original workaround in
arm_mmu500_reset implementation within ARM_SMMU_WORKAROUND_BROKEN_CPRE
config (defualts to on, CPRE would be disabled) and in QCOM SoCs default it
to off
(when ARM_SMMU_QCOM=Y -> switch ARM_SMMU_WORKAROUND_BROKEN_CPRE=N).
ARM_SMMU_QCOM is enabled by default, so please don't do that. People who
want to disable errata workarounds based on a hunch can do that themselves.
There's no need to try to do that automatically in Kconfig.
Okay I see, that seems better. To allow users to manually toggle the
config switch for
disabling errata workarounds based on their specific needs,
rather than having it enabled by default.
In silicon-errata.rst would updating ARM_SMMU_WORKAROUND_BROKEN_CPRE be okay
, as the config names are based on erratum number.
In this case, the Kconfig option covers a variety of errata so how about
we go with:
ARM_SMMU_MMU_500_CPRE_ERRATA
and then you can list all of the numbers in the "Erratum ID" column?
Ack, this name sounds self-explanatory to me. Thanks for the suggestion,
I'll proceed with this name and ensure documenting the known numbers in
Erratum ID column
<#826419, #841119, #562869, #1047329>
Thanks & regards,
Bibek
Will
