Re: [PATCH 1/1] arm64: dts: marvell: keep SMMU disabled by default for Armada 7040 and 8040

From: Gregory CLEMENT
Date: Mon Nov 30 2020 - 09:37:43 EST


Hi,

> FW has to configure devices' StreamIDs so that SMMU is able to lookup
> context and do proper translation later on. For Armada 7040 & 8040 and
> publicly available FW, most of the devices are configured properly,
> but some like ap_sdhci0, PCIe, NIC still remain unassigned which
> results in SMMU faults about unmatched StreamID (assuming
> ARM_SMMU_DISABLE_BYPASS_BY_DEFAUL=y).
>
> Since there is dependency on custom FW let SMMU be disabled by default.
> People who still willing to use SMMU need to enable manually and
> use ARM_SMMU_DISABLE_BYPASS_BY_DEFAUL=n (or via kernel command line)
> with extra caution.
>
> Fixes: 83a3545d9c37 ("arm64: dts: marvell: add SMMU support")
> Cc: <stable@xxxxxxxxxxxxxxx> # 5.9+
> Signed-off-by: Tomasz Nowicki <tn@xxxxxxxxxxxx>


Applied on mvebu/dt64

Thanks,

Gregory

> ---
> arch/arm64/boot/dts/marvell/armada-7040.dtsi | 4 ----
> arch/arm64/boot/dts/marvell/armada-8040.dtsi | 4 ----
> 2 files changed, 8 deletions(-)
>
> diff --git a/arch/arm64/boot/dts/marvell/armada-7040.dtsi b/arch/arm64/boot/dts/marvell/armada-7040.dtsi
> index 7a3198cd7a07..2f440711d21d 100644
> --- a/arch/arm64/boot/dts/marvell/armada-7040.dtsi
> +++ b/arch/arm64/boot/dts/marvell/armada-7040.dtsi
> @@ -15,10 +15,6 @@ / {
> "marvell,armada-ap806";
> };
>
> -&smmu {
> - status = "okay";
> -};
> -
> &cp0_pcie0 {
> iommu-map =
> <0x0 &smmu 0x480 0x20>,
> diff --git a/arch/arm64/boot/dts/marvell/armada-8040.dtsi b/arch/arm64/boot/dts/marvell/armada-8040.dtsi
> index 79e8ce59baa8..22c2d6ebf381 100644
> --- a/arch/arm64/boot/dts/marvell/armada-8040.dtsi
> +++ b/arch/arm64/boot/dts/marvell/armada-8040.dtsi
> @@ -15,10 +15,6 @@ / {
> "marvell,armada-ap806";
> };
>
> -&smmu {
> - status = "okay";
> -};
> -
> &cp0_pcie0 {
> iommu-map =
> <0x0 &smmu 0x480 0x20>,
> --
> 2.25.1
>

--
Gregory Clement, Bootlin
Embedded Linux and Kernel engineering
http://bootlin.com