2023-09-14 18:29:37

by Laurentiu Tudor

Subject: [PATCH] arm64: dts: ls208xa: use a pseudo-bus to constrain usb dma size

Wrap the usb controllers in an intermediate simple-bus and use it to
constrain the dma address size of these usb controllers to the 40b
that they generate toward the interconnect. This is required because
the SoC uses 48b address sizes and this mismatch would lead to smmu
context faults [1] because the usb generates 40b addresses while the
smmu page tables are populated with 48b wide addresses.

[1]
xhci-hcd xhci-hcd.0.auto: xHCI Host Controller
xhci-hcd xhci-hcd.0.auto: new USB bus registered, assigned bus number 1
xhci-hcd xhci-hcd.0.auto: hcc params 0x0220f66d hci version 0x100 quirks 0x0000000002000010
xhci-hcd xhci-hcd.0.auto: irq 108, io mem 0x03100000
xhci-hcd xhci-hcd.0.auto: xHCI Host Controller
xhci-hcd xhci-hcd.0.auto: new USB bus registered, assigned bus number 2
xhci-hcd xhci-hcd.0.auto: Host supports USB 3.0 SuperSpeed
arm-smmu 5000000.iommu: Unhandled context fault: fsr=0x402, iova=0xffffffb000, fsynr=0x0, cbfrsynra=0xc01, cb=3

Signed-off-by: Laurentiu Tudor <[email protected]>
---
.../arm64/boot/dts/freescale/fsl-ls208xa.dtsi | 46 +++++++++++--------
1 file changed, 27 insertions(+), 19 deletions(-)

diff --git a/arch/arm64/boot/dts/freescale/fsl-ls208xa.dtsi b/arch/arm64/boot/dts/freescale/fsl-ls208xa.dtsi
index d2f5345d0560..47cc7699ca16 100644
--- a/arch/arm64/boot/dts/freescale/fsl-ls208xa.dtsi
+++ b/arch/arm64/boot/dts/freescale/fsl-ls208xa.dtsi
@@ -1186,26 +1186,34 @@
dma-coherent;
};

- usb0: usb@3100000 {
- status = "disabled";
- compatible = "snps,dwc3";
- reg = <0x0 0x3100000 0x0 0x10000>;
- interrupts = <0 80 0x4>; /* Level high type */
- dr_mode = "host";
- snps,quirk-frame-length-adjustment = <0x20>;
- snps,dis_rxdet_inp3_quirk;
- snps,incr-burst-type-adjustment = <1>, <4>, <8>, <16>;
- };
+ aux_bus: aux_bus {
+ #address-cells = <2>;
+ #size-cells = <2>;
+ compatible = "simple-bus";
+ ranges;
+ dma-ranges = <0x0 0x0 0x0 0x0 0x100 0x00000000>;
+
+ usb0: usb@3100000 {
+ status = "disabled";
+ compatible = "snps,dwc3";
+ reg = <0x0 0x3100000 0x0 0x10000>;
+ interrupts = <0 80 0x4>; /* Level high type */
+ dr_mode = "host";
+ snps,quirk-frame-length-adjustment = <0x20>;
+ snps,dis_rxdet_inp3_quirk;
+ snps,incr-burst-type-adjustment = <1>, <4>, <8>, <16>;
+ };

- usb1: usb@3110000 {
- status = "disabled";
- compatible = "snps,dwc3";
- reg = <0x0 0x3110000 0x0 0x10000>;
- interrupts = <0 81 0x4>; /* Level high type */
- dr_mode = "host";
- snps,quirk-frame-length-adjustment = <0x20>;
- snps,dis_rxdet_inp3_quirk;
- snps,incr-burst-type-adjustment = <1>, <4>, <8>, <16>;
+ usb1: usb@3110000 {
+ status = "disabled";
+ compatible = "snps,dwc3";
+ reg = <0x0 0x3110000 0x0 0x10000>;
+ interrupts = <0 81 0x4>; /* Level high type */
+ dr_mode = "host";
+ snps,quirk-frame-length-adjustment = <0x20>;
+ snps,dis_rxdet_inp3_quirk;
+ snps,incr-burst-type-adjustment = <1>, <4>, <8>, <16>;
+ };
};

ccn@4000000 {
--
2.17.1

2023-09-15 02:25:18

by Krzysztof Kozlowski

Subject: Re: [PATCH] arm64: dts: ls208xa: use a pseudo-bus to constrain usb dma size

On 14/09/2023 16:56, Laurentiu Tudor wrote:
> Wrap the usb controllers in an intermediate simple-bus and use it to
> constrain the dma address size of these usb controllers to the 40b
> that they generate toward the interconnect. This is required because
> the SoC uses 48b address sizes and this mismatch would lead to smmu
> context faults [1] because the usb generates 40b addresses while the
> smmu page tables are populated with 48b wide addresses.
>
> [1]
> xhci-hcd xhci-hcd.0.auto: xHCI Host Controller
> xhci-hcd xhci-hcd.0.auto: new USB bus registered, assigned bus number 1
> xhci-hcd xhci-hcd.0.auto: hcc params 0x0220f66d hci version 0x100 quirks 0x0000000002000010
> xhci-hcd xhci-hcd.0.auto: irq 108, io mem 0x03100000
> xhci-hcd xhci-hcd.0.auto: xHCI Host Controller
> xhci-hcd xhci-hcd.0.auto: new USB bus registered, assigned bus number 2
> xhci-hcd xhci-hcd.0.auto: Host supports USB 3.0 SuperSpeed
> arm-smmu 5000000.iommu: Unhandled context fault: fsr=0x402, iova=0xffffffb000, fsynr=0x0, cbfrsynra=0xc01, cb=3
>
> Signed-off-by: Laurentiu Tudor <[email protected]>
> ---
> .../arm64/boot/dts/freescale/fsl-ls208xa.dtsi | 46 +++++++++++--------
> 1 file changed, 27 insertions(+), 19 deletions(-)
>
> diff --git a/arch/arm64/boot/dts/freescale/fsl-ls208xa.dtsi b/arch/arm64/boot/dts/freescale/fsl-ls208xa.dtsi
> index d2f5345d0560..47cc7699ca16 100644
> --- a/arch/arm64/boot/dts/freescale/fsl-ls208xa.dtsi
> +++ b/arch/arm64/boot/dts/freescale/fsl-ls208xa.dtsi
> @@ -1186,26 +1186,34 @@
> dma-coherent;
> };
>
> - usb0: usb@3100000 {
> - status = "disabled";
> - compatible = "snps,dwc3";
> - reg = <0x0 0x3100000 0x0 0x10000>;
> - interrupts = <0 80 0x4>; /* Level high type */
> - dr_mode = "host";
> - snps,quirk-frame-length-adjustment = <0x20>;
> - snps,dis_rxdet_inp3_quirk;
> - snps,incr-burst-type-adjustment = <1>, <4>, <8>, <16>;
> - };
> + aux_bus: aux_bus {

No underscores in node names. The node name should be anyway generic, so
just "bus".



Best regards,
Krzysztof