diff mbox series

[v3,2/2] dt-bindings: usb: snps,dwc3: Add 'snps,parkmode-disable-hs-quirk' quirk

Message ID 20230413100914.7890-2-stanley_chang@realtek.com
State Superseded
Headers show
Series [v3,1/2] usb: dwc3: core: add support for disabling High-speed park mode | expand

Commit Message

Stanley Chang[昌育德] April 13, 2023, 10:09 a.m. UTC
Add a new 'snps,parkmode-disable-hs-quirk' DT quirk to dwc3 core for
disable the high-speed parkmode.

For some USB wifi devices, if enable this feature it will reduce the
performance. Therefore, add an option for disabling HS park mode by
device-tree.

In Synopsys's dwc3 data book:
In a few high speed devices when an IN request is sent within 900ns of the
ACK of the previous packet, these devices send a NAK. When connected to
these devices, if required, the software can disable the park mode if you
see performance drop in your system. When park mode is disabled,
pipelining of multiple packet is disabled and instead one packet at a time
is requested by the scheduler. This allows up to 12 NAKs in a micro-frame
and improves performance of these slow devices.

Signed-off-by: Stanley Chang <stanley_chang@realtek.com>
---
v2 to v3 change:
1. Add the comment message.
2. cc the right maintainers.
---
 Documentation/devicetree/bindings/usb/snps,dwc3.yaml | 5 +++++
 1 file changed, 5 insertions(+)

Comments

Rob Herring (Arm) April 18, 2023, 8:52 p.m. UTC | #1
On Thu, 13 Apr 2023 18:09:14 +0800, Stanley Chang wrote:
> Add a new 'snps,parkmode-disable-hs-quirk' DT quirk to dwc3 core for
> disable the high-speed parkmode.
> 
> For some USB wifi devices, if enable this feature it will reduce the
> performance. Therefore, add an option for disabling HS park mode by
> device-tree.
> 
> In Synopsys's dwc3 data book:
> In a few high speed devices when an IN request is sent within 900ns of the
> ACK of the previous packet, these devices send a NAK. When connected to
> these devices, if required, the software can disable the park mode if you
> see performance drop in your system. When park mode is disabled,
> pipelining of multiple packet is disabled and instead one packet at a time
> is requested by the scheduler. This allows up to 12 NAKs in a micro-frame
> and improves performance of these slow devices.
> 
> Signed-off-by: Stanley Chang <stanley_chang@realtek.com>
> ---
> v2 to v3 change:
> 1. Add the comment message.
> 2. cc the right maintainers.
> ---
>  Documentation/devicetree/bindings/usb/snps,dwc3.yaml | 5 +++++
>  1 file changed, 5 insertions(+)
> 

Acked-by: Rob Herring <robh@kernel.org>
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
index be36956af53b..45ca967b8d14 100644
--- a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
+++ b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
@@ -232,6 +232,11 @@  properties:
       When set, all SuperSpeed bus instances in park mode are disabled.
     type: boolean
 
+  snps,parkmode-disable-hs-quirk:
+    description:
+      When set, all HighSpeed bus instances in park mode are disabled.
+    type: boolean
+
   snps,dis_metastability_quirk:
     description:
       When set, disable metastability workaround. CAUTION! Use only if you are