RE: Re: [PATCH] arm64: dts: imx8mq-evk: add one regulator used to power up pcie phy

From: Richard Zhu
Date: Sun Apr 25 2021 - 21:28:41 EST


> -----Original Message-----
<snipped>
> Subject: Re: [PATCH] arm64: dts: imx8mq-evk: add one regulator used
> to power up pcie phy
> On Mon, Mar 29, 2021 at 04:06:03PM +0800, Richard Zhu wrote:
> > Both 1.8v and 3.3v power supplies can be used by i.MX8MQ PCIe PHY.
> > In default, the PCIE_VPH voltage is suggested to be 1.8v refer to data
> > sheet. When PCIE_VPH is supplied by 3.3v in the HW schematic design,
> > the VREG_BYPASS bits of GPR registers should be cleared from default
> > value 1b'1 to 1b'0. Thus, the internal 3v3 to 1v8 translator would be
> > turned on.
> >
> > Signed-off-by: Richard Zhu <hongxing.zhu@xxxxxxx>
> > Reviewed-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
> > ---
> > arch/arm64/boot/dts/freescale/imx8mq-evk.dts | 1 +
> > 1 file changed, 1 insertion(+)
> >
> > diff --git a/arch/arm64/boot/dts/freescale/imx8mq-evk.dts
> > b/arch/arm64/boot/dts/freescale/imx8mq-evk.dts
> > index 85b045253a0e..4d2035e3dd7c 100644
> > --- a/arch/arm64/boot/dts/freescale/imx8mq-evk.dts
> > +++ b/arch/arm64/boot/dts/freescale/imx8mq-evk.dts
> > @@ -318,6 +318,7 @@
> > <&clk IMX8MQ_CLK_PCIE1_PHY>,
> > <&pcie0_refclk>;
> > clock-names = "pcie", "pcie_aux", "pcie_phy", "pcie_bus";
> > + vph-supply = <&vgen5_reg>;
>
> Hmm, I do not see this in the bindings doc.
[Richard Zhu] Hi Shawn:
The binding document changes are going to PCI tree by the following patch.

https://patchwork.kernel.org/project/linux-pci/patch/1617091701-6444-2-git-send-email-hongxing.zhu@xxxxxxx/

Best Regards
Richard Zhu

>
> Shawn
>
> > status = "okay";
> > };
> >
> > --
> > 2.17.1
> >