Re: [PATCH v9 3/5] iommu/arm-smmu: introduction of ACTLR for custom prefetcher settings

From: Dmitry Baryshkov
Date: Fri Feb 09 2024 - 05:53:30 EST


On Tue, 23 Jan 2024 at 16:46, Bibek Kumar Patro
<quic_bibekkum@xxxxxxxxxxx> wrote:
>
> Currently in Qualcomm SoCs the default prefetch is set to 1 which allows
> the TLB to fetch just the next page table. MMU-500 features ACTLR
> register which is implementation defined and is used for Qualcomm SoCs
> to have a custom prefetch setting enabling TLB to prefetch the next set
> of page tables accordingly allowing for faster translations.
>
> ACTLR value is unique for each SMR (Stream matching register) and stored
> in a pre-populated table. This value is set to the register during
> context bank initialisation.
>
> Signed-off-by: Bibek Kumar Patro <quic_bibekkum@xxxxxxxxxxx>
> ---
> drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 61 ++++++++++++++++++++++
> drivers/iommu/arm/arm-smmu/arm-smmu-qcom.h | 16 +++++-
> drivers/iommu/arm/arm-smmu/arm-smmu.c | 5 +-
> drivers/iommu/arm/arm-smmu/arm-smmu.h | 5 ++
> 4 files changed, 84 insertions(+), 3 deletions(-)


Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>


--
With best wishes
Dmitry