arch/arm64/boot/dts/qcom/glymur.dtsi | 10 ++++++++++ 1 file changed, 10 insertions(+)
All five USB controller nodes on Glymur (usb_0, usb_1, usb_2, usb_hs,
usb_mp) are missing the dma-coherent property, which Hamoa carries on
all of its USB controllers. Krishna Kurapati confirmed the Glymur USB
controllers are dma-coherent [1].
Without the property the kernel treats USB DMA buffers as non-coherent
and performs cache maintenance on every transfer, which coherent
hardware makes redundant.
Follow-up to the clock/power/bandwidth votes patch [2], kept separate
so the already-reviewed patch stands as is.
Tested on an Asus Zenbook A16 (UX3607OA): all controllers enumerate
their devices as before and a 64 MiB write plus two O_DIRECT
read-backs over USB mass storage produce identical checksums.
[1] https://lore.kernel.org/linux-arm-msm/f92cc91e-6e5c-4375-aaa6-f079a165f4b5@oss.qualcomm.com/
[2] https://lore.kernel.org/linux-arm-msm/20260812083522.774711-1-greg@ferrisoft.com/
Fixes: 4eee57dd4df9 ("arm64: dts: qcom: glymur: Add USB related nodes")
Signed-off-by: Greg Ociepka <greg@ferrisoft.com>
Assisted-by: Claude:fable-5
---
arch/arm64/boot/dts/qcom/glymur.dtsi | 10 ++++++++++
1 file changed, 10 insertions(+)
--- a/arch/arm64/boot/dts/qcom/glymur.dtsi
+++ b/arch/arm64/boot/dts/qcom/glymur.dtsi
@@ -4605,6 +4605,8 @@
usb-role-switch;
wakeup-source;
+ dma-coherent;
+
status = "disabled";
ports {
@@ -4681,6 +4683,8 @@
usb-role-switch;
wakeup-source;
+ dma-coherent;
+
status = "disabled";
ports {
@@ -4757,6 +4761,8 @@
usb-role-switch;
wakeup-source;
+ dma-coherent;
+
status = "disabled";
ports {
@@ -4847,6 +4853,8 @@
usb-role-switch;
wakeup-source;
+ dma-coherent;
+
status = "disabled";
};
@@ -4919,6 +4927,8 @@
dr_mode = "host";
wakeup-source;
+ dma-coherent;
+
status = "disabled";
};
--
2.50.1
On Wed, 12 Aug 2026 17:40:14 +0200, Greg Ociepka wrote:
> All five USB controller nodes on Glymur (usb_0, usb_1, usb_2, usb_hs,
> usb_mp) are missing the dma-coherent property, which Hamoa carries on
> all of its USB controllers. Krishna Kurapati confirmed the Glymur USB
> controllers are dma-coherent [1].
>
> Without the property the kernel treats USB DMA buffers as non-coherent
> and performs cache maintenance on every transfer, which coherent
> hardware makes redundant.
>
> [...]
Applied, thanks!
[1/1] arm64: dts: qcom: glymur: Mark USB controllers dma-coherent
commit: e62df36f34949aebe016c5c81e34baa7a9eca427
Best regards,
--
Bjorn Andersson <andersson@kernel.org>
On 26-08-12 17:40:14, Greg Ociepka wrote:
> All five USB controller nodes on Glymur (usb_0, usb_1, usb_2, usb_hs,
> usb_mp) are missing the dma-coherent property, which Hamoa carries on
> all of its USB controllers. Krishna Kurapati confirmed the Glymur USB
> controllers are dma-coherent [1].
>
> Without the property the kernel treats USB DMA buffers as non-coherent
> and performs cache maintenance on every transfer, which coherent
> hardware makes redundant.
>
> Follow-up to the clock/power/bandwidth votes patch [2], kept separate
> so the already-reviewed patch stands as is.
>
> Tested on an Asus Zenbook A16 (UX3607OA): all controllers enumerate
> their devices as before and a 64 MiB write plus two O_DIRECT
> read-backs over USB mass storage produce identical checksums.
>
> [1] https://lore.kernel.org/linux-arm-msm/f92cc91e-6e5c-4375-aaa6-f079a165f4b5@oss.qualcomm.com/
> [2] https://lore.kernel.org/linux-arm-msm/20260812083522.774711-1-greg@ferrisoft.com/
>
> Fixes: 4eee57dd4df9 ("arm64: dts: qcom: glymur: Add USB related nodes")
> Signed-off-by: Greg Ociepka <greg@ferrisoft.com>
> Assisted-by: Claude:fable-5
Reviewed-by: Abel Vesa <abel.vesa@oss.qualcomm.com>
On 8/12/2026 9:10 PM, Greg Ociepka wrote:
> All five USB controller nodes on Glymur (usb_0, usb_1, usb_2, usb_hs,
> usb_mp) are missing the dma-coherent property, which Hamoa carries on
> all of its USB controllers. Krishna Kurapati confirmed the Glymur USB
> controllers are dma-coherent [1].
>
> Without the property the kernel treats USB DMA buffers as non-coherent
> and performs cache maintenance on every transfer, which coherent
> hardware makes redundant.
>
> Follow-up to the clock/power/bandwidth votes patch [2], kept separate
> so the already-reviewed patch stands as is.
>
> Tested on an Asus Zenbook A16 (UX3607OA): all controllers enumerate
> their devices as before and a 64 MiB write plus two O_DIRECT
> read-backs over USB mass storage produce identical checksums.
>
> [1] https://lore.kernel.org/linux-arm-msm/f92cc91e-6e5c-4375-aaa6-f079a165f4b5@oss.qualcomm.com/
> [2] https://lore.kernel.org/linux-arm-msm/20260812083522.774711-1-greg@ferrisoft.com/
>
> Fixes: 4eee57dd4df9 ("arm64: dts: qcom: glymur: Add USB related nodes")
> Signed-off-by: Greg Ociepka <greg@ferrisoft.com>
> Assisted-by: Claude:fable-5
Reviewed-by: Gopikrishna Garmidi <gopikrishna.garmidi@oss.qualcomm.com>
On Wed, Aug 12, 2026 at 05:40:14PM +0200, Greg Ociepka wrote:
> All five USB controller nodes on Glymur (usb_0, usb_1, usb_2, usb_hs,
> usb_mp) are missing the dma-coherent property, which Hamoa carries on
> all of its USB controllers. Krishna Kurapati confirmed the Glymur USB
> controllers are dma-coherent [1].
>
> Without the property the kernel treats USB DMA buffers as non-coherent
> and performs cache maintenance on every transfer, which coherent
> hardware makes redundant.
>
> Follow-up to the clock/power/bandwidth votes patch [2], kept separate
> so the already-reviewed patch stands as is.
>
> Tested on an Asus Zenbook A16 (UX3607OA): all controllers enumerate
> their devices as before and a 64 MiB write plus two O_DIRECT
> read-backs over USB mass storage produce identical checksums.
>
> [1] https://lore.kernel.org/linux-arm-msm/f92cc91e-6e5c-4375-aaa6-f079a165f4b5@oss.qualcomm.com/
> [2] https://lore.kernel.org/linux-arm-msm/20260812083522.774711-1-greg@ferrisoft.com/
>
> Fixes: 4eee57dd4df9 ("arm64: dts: qcom: glymur: Add USB related nodes")
> Signed-off-by: Greg Ociepka <greg@ferrisoft.com>
> Assisted-by: Claude:fable-5
> ---
> arch/arm64/boot/dts/qcom/glymur.dtsi | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
--
With best wishes
Dmitry
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