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[v3,0/6] add NXP imx8mp usb support

Message ID 1600771612-30727-1-git-send-email-jun.li@nxp.com
Headers show
Series add NXP imx8mp usb support | expand

Message

Jun Li Sept. 22, 2020, 10:46 a.m. UTC
NXP imx8MPlus integrates 2 indentical dwc3 3.30b IP with additional wakeup
logic to support low power, this wakeup logic has a separated interrupt
which can generate events with suspend clock(32K); due to SoC integration
limitation, a few quriks required, instead of create new properties flags,
introduce platform data and pass it from glue layer to dwc3 core, those xhci
private data can further pass to xhci-plat.

changes for v3:
- Add dwc3 core related clocks into dwc3 core node, and glue layer driver
  only handle the clocks(hsio and suspend) for glue block, this is to
  match real HW.
- Change to use property "xhci-64bit-support-disable" to disable 64bit DMA
  as imx8mp USB integration actully can't support it, so remove platform
  data in v2.
- Some changes of imx8mp usb driver binding doc to address comments from Rob

Changes for v2:
- Drop the 2 patches for new property("snps,xhci-dis-64bit-support-quirk")
  introduction, as suggested, imply by SoC compatible string, this is done
  by introduce dwc3 core platform data and pass the xhci_plat_priv to
  xhci-plat for those xhci quirks, so a new patch added:
  [1/5] usb: dwc3: add platform data to dwc3 core device to pass data.
  this patch is based on Peter's one patch which is also in review:
  https://patchwork.kernel.org/patch/11640945/
- dts change, use the USB power function of TRL logic instead of a always-on
  regulator to control vbus on/off.
- Some changes to address Peter's command on patch [2/5].

Li Jun (6):
  dt-bindings: usb: xhci: add property to disable xhci 64bit support
  usb: host: xhci-plat: add support of XHCI_NO_64BIT_SUPPORT via
    property
  dt-bindings: usb: dwc3-imx8mp: add imx8mp dwc3 glue bindings
  usb: dwc3: add imx8mp dwc3 glue layer driver
  arm64: dtsi: imx8mp: add usb nodes
  arm64: dts: imx8mp-evk: enable usb1 as host mode

 .../devicetree/bindings/usb/fsl,imx8mp-dwc3.yaml   |  99 ++++++
 Documentation/devicetree/bindings/usb/usb-xhci.txt |   3 +
 arch/arm64/boot/dts/freescale/imx8mp-evk.dts       |  21 ++
 arch/arm64/boot/dts/freescale/imx8mp.dtsi          |  88 +++++
 drivers/usb/dwc3/Kconfig                           |  10 +
 drivers/usb/dwc3/Makefile                          |   1 +
 drivers/usb/dwc3/dwc3-imx8mp.c                     | 363 +++++++++++++++++++++
 drivers/usb/host/xhci-plat.c                       |   4 +
 8 files changed, 589 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/usb/fsl,imx8mp-dwc3.yaml
 create mode 100644 drivers/usb/dwc3/dwc3-imx8mp.c

Comments

Krzysztof Kozlowski Sept. 22, 2020, 2:39 p.m. UTC | #1
On Tue, 22 Sep 2020 at 12:56, Li Jun <jun.li@nxp.com> wrote:
>
> imx8mp integrates 2 identical dwc3 based USB3 controllers and
> Synopsys phys, each instance has additional wakeup logic to
> support low power mode, so the glue layer need a node with dwc3
> core sub node.
>
> Signed-off-by: Li Jun <jun.li@nxp.com>
> ---
>  arch/arm64/boot/dts/freescale/imx8mp.dtsi | 88 +++++++++++++++++++++++++++++++
>  1 file changed, 88 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/freescale/imx8mp.dtsi b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> index 9de2aa1..1b7ed4c 100644
> --- a/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> +++ b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> @@ -750,5 +750,93 @@
>                         reg = <0x3d800000 0x400000>;
>                         interrupts = <GIC_SPI 98 IRQ_TYPE_LEVEL_HIGH>;
>                 };
> +
> +               usb3_phy0: usb-phy@381f0040 {
> +                       compatible = "fsl,imx8mp-usb-phy";
> +                       reg = <0x381f0040 0x40>;
> +                       clocks = <&clk IMX8MP_CLK_USB_PHY_ROOT>;
> +                       clock-names = "phy";
> +                       assigned-clocks = <&clk IMX8MP_CLK_USB_PHY_REF>;
> +                       assigned-clock-parents = <&clk IMX8MP_CLK_24M>;
> +                       #phy-cells = <0>;
> +                       status = "disabled";
> +               };
> +
> +               usb3_0: usb@32f10100 {
> +                       compatible = "fsl,imx8mp-dwc3";
> +                       reg = <0x32f10100 0x8>;
> +                       clocks = <&clk IMX8MP_CLK_HSIO_ROOT>,
> +                                <&clk IMX8MP_CLK_USB_ROOT>;
> +                       clock-names = "hsio", "suspend";
> +                       interrupts = <GIC_SPI 148 IRQ_TYPE_LEVEL_HIGH>;
> +                       #address-cells = <1>;
> +                       #size-cells = <1>;
> +                       ranges;
> +                       status = "disabled";
> +
> +                       usb_dwc3_0: dwc3@38100000 {
> +                               compatible = "snps,dwc3";
> +                               reg = <0x38100000 0x10000>;
> +                               clocks = <&clk IMX8MP_CLK_HSIO_AXI>,
> +                                        <&clk IMX8MP_CLK_USB_CORE_REF>,
> +                                        <&clk IMX8MP_CLK_USB_ROOT>;
> +                               clock-names = "bus_early", "ref", "suspend";
> +                               assigned-clocks = <&clk IMX8MP_CLK_HSIO_AXI>;
> +                               assigned-clock-parents = <&clk IMX8MP_SYS_PLL2_500M>;
> +                               assigned-clock-rates = <500000000>;
> +                               interrupts = <GIC_SPI 40 IRQ_TYPE_LEVEL_HIGH>;
> +                               phys = <&usb3_phy0>, <&usb3_phy0>;
> +                               phy-names = "usb2-phy", "usb3-phy";
> +                               snps,dis-u2-freeclk-exists-quirk;
> +                               xhci-64bit-support-disable;
> +                               status = "disabled";
> +                       };
> +
> +               };
> +
> +               usb3_phy1: usb-phy@382f0040 {
> +                       compatible = "fsl,imx8mp-usb-phy";
> +                       reg = <0x382f0040 0x40>;
> +                       clocks = <&clk IMX8MP_CLK_USB_PHY_ROOT>;
> +                       clock-names = "phy";
> +                       assigned-clocks = <&clk IMX8MP_CLK_USB_PHY_REF>;
> +                       assigned-clock-parents = <&clk IMX8MP_CLK_24M>;
> +                       #phy-cells = <0>;
> +                       status = "disabled";
> +               };
> +
> +               usb3_1: usb@32f10108 {
> +                       compatible = "fsl,imx8mp-dwc3";
> +                       reg = <0x32f10108 0x8>;
> +                       clocks = <&clk IMX8MP_CLK_HSIO_ROOT>,
> +                                <&clk IMX8MP_CLK_USB_ROOT>;
> +                       clock-names = "hsio", "suspend";
> +                       assigned-clocks = <&clk IMX8MP_CLK_HSIO_AXI_SRC>;

This does not validate against your own schema:
arch/arm64/boot/dts/freescale/imx8mp-evk.dt.yaml: usb@32f10108:
'assigned-clock-parents', 'assigned-clock-rates', 'assigned-clocks' do
not match any of the regexes: '^dwc3@[0-9a-f]+$', 'pinctrl-[0-9]+'

Please, stop adding new schema and DTS which from day one have
warnings/violations.

It's really a lot of effort (and commits) to clean this up later.

Best regards,
Krzysztof
Jun Li Sept. 22, 2020, 4:45 p.m. UTC | #2
> -----Original Message-----

> From: Krzysztof Kozlowski <krzk@kernel.org>

> Sent: Tuesday, September 22, 2020 10:33 PM

> To: Jun Li <jun.li@nxp.com>

> Cc: robh+dt@kernel.org; shawnguo@kernel.org; balbi@kernel.org;

> mathias.nyman@intel.com; gregkh@linuxfoundation.org;

> s.hauer@pengutronix.de; kernel@pengutronix.de; festevam@gmail.com;

> dl-linux-imx <linux-imx@nxp.com>; Anson Huang <anson.huang@nxp.com>;

> Aisheng Dong <aisheng.dong@nxp.com>; Peng Fan <peng.fan@nxp.com>; Andy Duan

> <fugang.duan@nxp.com>; Joakim Zhang <qiangqing.zhang@nxp.com>; Horia

> Geanta <horia.geanta@nxp.com>; linux-usb@vger.kernel.org;

> devicetree@vger.kernel.org; linux-arm-kernel@lists.infradead.org

> Subject: Re: [PATCH v3 3/6] dt-bindings: usb: dwc3-imx8mp: add imx8mp dwc3

> glue bindings

> 

> On Tue, 22 Sep 2020 at 12:56, Li Jun <jun.li@nxp.com> wrote:

> >

> > NXP imx8mp integrates 2 dwc3 3.30b IP and add some wakeup logic to

> > support low power mode, the glue layer is for this wakeup

> > functionality, which has a separated interrupt, can support wakeup

> > from U3 and connect events for host, and vbus wakeup for device.

> >

> > Signed-off-by: Li Jun <jun.li@nxp.com>

> > ---

> >  .../devicetree/bindings/usb/fsl,imx8mp-dwc3.yaml   | 99

> ++++++++++++++++++++++

> >  1 file changed, 99 insertions(+)

> >

> > diff --git

> > a/Documentation/devicetree/bindings/usb/fsl,imx8mp-dwc3.yaml

> > b/Documentation/devicetree/bindings/usb/fsl,imx8mp-dwc3.yaml

> > new file mode 100644

> > index 0000000..a5d5566

> > --- /dev/null

> > +++ b/Documentation/devicetree/bindings/usb/fsl,imx8mp-dwc3.yaml

> > @@ -0,0 +1,99 @@

> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) # Copyright

> > +(c) 2020 NXP %YAML 1.2

> > +---

> > +$id:

> >

> +https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fdevi

> >

> +cetree.org%2Fschemas%2Fusb%2Ffsl%2Cimx8mp-dwc3.yaml%23&amp;data=02%7C

> >

> +01%7Cjun.li%40nxp.com%7Ceaedeb64ec15472183d108d85f046841%7C686ea1d3bc

> >

> +2b4c6fa92cd99c5c301635%7C0%7C0%7C637363819819667936&amp;sdata=IvFQ8l0

> > +7VXUMbG8riyITSTZb1P50oIXs%2BkAV%2FeX8ntk%3D&amp;reserved=0

> > +$schema:

> >

> +https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fdevi

> >

> +cetree.org%2Fmeta-schemas%2Fcore.yaml%23&amp;data=02%7C01%7Cjun.li%40

> >

> +nxp.com%7Ceaedeb64ec15472183d108d85f046841%7C686ea1d3bc2b4c6fa92cd99c

> >

> +5c301635%7C0%7C0%7C637363819819677934&amp;sdata=H3%2BcwgiLKBynHv4N%2F

> > +dogBi3SwaizVHmqieJXVrErv0I%3D&amp;reserved=0

> > +

> > +title: NXP iMX8MP Soc USB Controller

> > +

> > +maintainers:

> > +  - Li Jun <jun.li@nxp.com>

> > +

> > +properties:

> > +  compatible:

> > +    items:

> 

> Items are not necessary

> 

> 

> > +    - const: fsl,imx8mp-dwc3

> > +

> > +  reg:

> > +    maxItems: 1

> > +    description: Address and length of the register set for the wrapper

> of

> > +      dwc3 core on the SOC.

> > +

> > +  "#address-cells":

> > +    enum: [ 1, 2 ]

> > +

> > +  "#size-cells":

> > +    enum: [ 1, 2 ]

> > +

> > +  ranges: true

> > +

> > +  interrupts:

> > +    maxItems: 1

> > +    description: The interrupt that is asserted when a wakeup event is

> > +      received.

> > +

> > +  clocks:

> > +    description:

> > +      A list of phandle and clock-specifier pairs for the clocks

> > +      listed in clock-names.

> > +    items:

> > +      - description: system hsio root clock.

> > +      - description: suspend clock, used for usb wakeup logic.

> > +

> > +  clock-names:

> > +    items:

> > +      - const: hsio

> > +      - const: suspend

> > +

> > +# Required child node:

> > +

> > +patternProperties:

> > +  "^dwc3@[0-9a-f]+$":

> > +    type: object

> > +    description:

> > +      A child node must exist to represent the core DWC3 IP block

> > +      The content of the node is defined in dwc3.txt.

> > +

> > +required:

> > +  - compatible

> > +  - reg

> > +  - "#address-cells"

> > +  - "#size-cells"

> > +  - ranges

> > +  - clocks

> > +  - clock-names

> > +  - interrupts

> > +

> > +additionalProperties: false

> 

> Do you actually validate your DTS changes with this schema? They do not look

> like passing the validation...


I did run dt_binding_check, maybe I missed some errors as there are always some other
failures, I will re-run to double check.

Li Jun
> 

> Best regards,

> Krzysztof
Sascha Hauer Sept. 23, 2020, 7:50 a.m. UTC | #3
On Tue, Sep 22, 2020 at 06:46:51PM +0800, Li Jun wrote:
> imx8mp integrates 2 identical dwc3 based USB3 controllers and
> Synopsys phys, each instance has additional wakeup logic to
> support low power mode, so the glue layer need a node with dwc3
> core sub node.
> 
> Signed-off-by: Li Jun <jun.li@nxp.com>
> ---
>  arch/arm64/boot/dts/freescale/imx8mp.dtsi | 88 +++++++++++++++++++++++++++++++
>  1 file changed, 88 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/freescale/imx8mp.dtsi b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> index 9de2aa1..1b7ed4c 100644
> --- a/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> +++ b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> +		usb3_1: usb@32f10108 {
> +			compatible = "fsl,imx8mp-dwc3";
> +			reg = <0x32f10108 0x8>;
> +			clocks = <&clk IMX8MP_CLK_HSIO_ROOT>,
> +				 <&clk IMX8MP_CLK_USB_ROOT>;
> +			clock-names = "hsio", "suspend";
> +			assigned-clocks = <&clk IMX8MP_CLK_HSIO_AXI_SRC>;

In Linux-5.9-rc6 this clock doesn't exist anymore. Should be
IMX8MP_CLK_HSIO_AXI

> +			assigned-clock-parents = <&clk IMX8MP_SYS_PLL2_500M>;
> +			assigned-clock-rates = <500000000>;
> +			interrupts = <GIC_SPI 149 IRQ_TYPE_LEVEL_HIGH>;
> +			#address-cells = <1>;
> +			#size-cells = <1>;
> +			ranges;
> +			status = "disabled";
> +
> +			usb_dwc3_1: dwc3@38200000 {
> +				compatible = "snps,dwc3";
> +				reg = <0x38200000 0x10000>;
> +				clocks = <&clk IMX8MP_CLK_HSIO_AXI>,
> +					 <&clk IMX8MP_CLK_USB_CORE_REF>,
> +					 <&clk IMX8MP_CLK_USB_ROOT>;
> +				clock-names = "bus_early", "ref", "suspend";
> +				assigned-clocks = <&clk IMX8MP_CLK_HSIO_AXI>;
> +				assigned-clock-parents = <&clk IMX8MP_SYS_PLL2_500M>;
> +				assigned-clock-rates = <500000000>;
> +				interrupts = <GIC_SPI 41 IRQ_TYPE_LEVEL_HIGH>;
> +				phys = <&usb3_phy1>, <&usb3_phy1>;
> +				phy-names = "usb2-phy", "usb3-phy";
> +				snps,dis-u2-freeclk-exists-quirk;
> +				xhci-64bit-support-disable;
> +				status = "disabled";

Does it make sense for a board to enable the parent node and leave this
one disabled? If not you can drop this status = "disabled" here.

Sascha
Jun Li Sept. 23, 2020, 8:49 a.m. UTC | #4
> -----Original Message-----
> From: Sascha Hauer <s.hauer@pengutronix.de>
> Sent: Wednesday, September 23, 2020 3:51 PM
> To: Jun Li <jun.li@nxp.com>
> Cc: robh+dt@kernel.org; shawnguo@kernel.org; balbi@kernel.org;
> mathias.nyman@intel.com; gregkh@linuxfoundation.org;
> kernel@pengutronix.de; festevam@gmail.com; dl-linux-imx
> <linux-imx@nxp.com>; Anson Huang <anson.huang@nxp.com>; Aisheng Dong
> <aisheng.dong@nxp.com>; Peng Fan <peng.fan@nxp.com>; Andy Duan
> <fugang.duan@nxp.com>; Joakim Zhang <qiangqing.zhang@nxp.com>; Horia
> Geanta <horia.geanta@nxp.com>; linux-usb@vger.kernel.org;
> devicetree@vger.kernel.org; linux-arm-kernel@lists.infradead.org
> Subject: Re: [PATCH v3 5/6] arm64: dtsi: imx8mp: add usb nodes
> 
> On Tue, Sep 22, 2020 at 06:46:51PM +0800, Li Jun wrote:
> > imx8mp integrates 2 identical dwc3 based USB3 controllers and Synopsys
> > phys, each instance has additional wakeup logic to support low power
> > mode, so the glue layer need a node with dwc3 core sub node.
> >
> > Signed-off-by: Li Jun <jun.li@nxp.com>
> > ---
> >  arch/arm64/boot/dts/freescale/imx8mp.dtsi | 88
> > +++++++++++++++++++++++++++++++
> >  1 file changed, 88 insertions(+)
> >
> > diff --git a/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> > b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> > index 9de2aa1..1b7ed4c 100644
> > --- a/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> > +++ b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> > +		usb3_1: usb@32f10108 {
> > +			compatible = "fsl,imx8mp-dwc3";
> > +			reg = <0x32f10108 0x8>;
> > +			clocks = <&clk IMX8MP_CLK_HSIO_ROOT>,
> > +				 <&clk IMX8MP_CLK_USB_ROOT>;
> > +			clock-names = "hsio", "suspend";
> > +			assigned-clocks = <&clk IMX8MP_CLK_HSIO_AXI_SRC>;
> 
> In Linux-5.9-rc6 this clock doesn't exist anymore. Should be
> IMX8MP_CLK_HSIO_AXI

Will change.

> 
> > +			assigned-clock-parents = <&clk IMX8MP_SYS_PLL2_500M>;
> > +			assigned-clock-rates = <500000000>;
> > +			interrupts = <GIC_SPI 149 IRQ_TYPE_LEVEL_HIGH>;
> > +			#address-cells = <1>;
> > +			#size-cells = <1>;
> > +			ranges;
> > +			status = "disabled";
> > +
> > +			usb_dwc3_1: dwc3@38200000 {
> > +				compatible = "snps,dwc3";
> > +				reg = <0x38200000 0x10000>;
> > +				clocks = <&clk IMX8MP_CLK_HSIO_AXI>,
> > +					 <&clk IMX8MP_CLK_USB_CORE_REF>,
> > +					 <&clk IMX8MP_CLK_USB_ROOT>;
> > +				clock-names = "bus_early", "ref", "suspend";
> > +				assigned-clocks = <&clk IMX8MP_CLK_HSIO_AXI>;
> > +				assigned-clock-parents = <&clk IMX8MP_SYS_PLL2_500M>;
> > +				assigned-clock-rates = <500000000>;
> > +				interrupts = <GIC_SPI 41 IRQ_TYPE_LEVEL_HIGH>;
> > +				phys = <&usb3_phy1>, <&usb3_phy1>;
> > +				phy-names = "usb2-phy", "usb3-phy";
> > +				snps,dis-u2-freeclk-exists-quirk;
> > +				xhci-64bit-support-disable;
> > +				status = "disabled";
> 
> Does it make sense for a board to enable the parent node and leave this one
> disabled? If not you can drop this status = "disabled" here.

OK, will drop it.

Thanks
Li Jun
> 
> Sascha
> 
> --
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Rob Herring Sept. 29, 2020, 6:11 p.m. UTC | #5
On Tue, Sep 22, 2020 at 06:46:47PM +0800, Li Jun wrote:
> Add a property "xhci-64bit-support-disable" to disable xhci 64bit address
> dma, some SoC integration may not support 64bit DMA but the AC64 bit
> (bit 0) of HCCPARAMS1 is kept to be 1.

Use 'dma-ranges' for this.

> Signed-off-by: Li Jun <jun.li@nxp.com>
> ---
>  Documentation/devicetree/bindings/usb/usb-xhci.txt | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/usb/usb-xhci.txt b/Documentation/devicetree/bindings/usb/usb-xhci.txt
> index 0c5cff8..26446fb 100644
> --- a/Documentation/devicetree/bindings/usb/usb-xhci.txt
> +++ b/Documentation/devicetree/bindings/usb/usb-xhci.txt
> @@ -28,6 +28,9 @@ Optional properties:
>    - quirk-broken-port-ped: set if the controller has broken port disable mechanism
>    - imod-interval-ns: default interrupt moderation interval is 5000ns
>    - phys : see usb-hcd.yaml in the current directory
> +  - xhci-64bit-support-disable: set if the AC64 bit (bit 0) of HCCPARAMS1 is
> +    set to be 1, but the controller actually can't handle 64-bit address
> +    due to SoC integration.
>  
>  additionally the properties from usb-hcd.yaml (in the current directory) are
>  supported.
> -- 
> 2.7.4
>
Jun Li Oct. 2, 2020, 4:39 p.m. UTC | #6
Hi Rob,
> -----Original Message-----
> From: Rob Herring <robh@kernel.org>
> Sent: Wednesday, September 30, 2020 2:11 AM
> To: Jun Li <jun.li@nxp.com>
> Cc: shawnguo@kernel.org; balbi@kernel.org; mathias.nyman@intel.com;
> gregkh@linuxfoundation.org; s.hauer@pengutronix.de;
> kernel@pengutronix.de; festevam@gmail.com; dl-linux-imx
> <linux-imx@nxp.com>; Anson Huang <anson.huang@nxp.com>; Aisheng Dong
> <aisheng.dong@nxp.com>; Peng Fan <peng.fan@nxp.com>; Andy Duan
> <fugang.duan@nxp.com>; Joakim Zhang <qiangqing.zhang@nxp.com>; Horia
> Geanta <horia.geanta@nxp.com>; linux-usb@vger.kernel.org;
> devicetree@vger.kernel.org; linux-arm-kernel@lists.infradead.org
> Subject: Re: [PATCH v3 1/6] dt-bindings: usb: xhci: add property to disable
> xhci 64bit support
> 
> On Tue, Sep 22, 2020 at 06:46:47PM +0800, Li Jun wrote:
> > Add a property "xhci-64bit-support-disable" to disable xhci 64bit
> > address dma, some SoC integration may not support 64bit DMA but the
> > AC64 bit (bit 0) of HCCPARAMS1 is kept to be 1.
> 
> Use 'dma-ranges' for this.

Thanks, sent out v4 with dma-ranges property approach.

Li Jun
> 
> > Signed-off-by: Li Jun <jun.li@nxp.com>
> > ---
> >  Documentation/devicetree/bindings/usb/usb-xhci.txt | 3 +++
> >  1 file changed, 3 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/usb/usb-xhci.txt
> > b/Documentation/devicetree/bindings/usb/usb-xhci.txt
> > index 0c5cff8..26446fb 100644
> > --- a/Documentation/devicetree/bindings/usb/usb-xhci.txt
> > +++ b/Documentation/devicetree/bindings/usb/usb-xhci.txt
> > @@ -28,6 +28,9 @@ Optional properties:
> >    - quirk-broken-port-ped: set if the controller has broken port disable
> mechanism
> >    - imod-interval-ns: default interrupt moderation interval is 5000ns
> >    - phys : see usb-hcd.yaml in the current directory
> > +  - xhci-64bit-support-disable: set if the AC64 bit (bit 0) of HCCPARAMS1
> is
> > +    set to be 1, but the controller actually can't handle 64-bit address
> > +    due to SoC integration.
> >
> >  additionally the properties from usb-hcd.yaml (in the current
> > directory) are  supported.
> > --
> > 2.7.4
> >