2020-11-05 11:28:25

by Tomasz Nowicki

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

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: <[email protected]> # 5.9+
Signed-off-by: Tomasz Nowicki <[email protected]>
---
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

2020-11-30 14:40:32

by Gregory CLEMENT

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

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: <[email protected]> # 5.9+
> Signed-off-by: Tomasz Nowicki <[email protected]>


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