Re: [PATCH] arm64: dts: imx8mp: add vpu pgc nodes

[Greg Ungerer <gerg@linux-m68k.org>]

On 22/8/22 14:45, Peng Fan wrote:
> Add i.MX8MP PGC nodes for vpu, which are used to supply power for VPU.
> 
> Signed-off-by: Peng Fan <peng.fan@nxp.com>
> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
> ---
>  arch/arm64/boot/dts/freescale/imx8mp.dtsi | 27 +++++++++++++++++++++++
>  1 file changed, 27 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/freescale/imx8mp.dtsi b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> index 0b165f98a82c..34af983b0210 100644
> --- a/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> +++ b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> @@ -598,6 +598,33 @@ pgc_ispdwp: power-domain@18 {
>                                                 reg = <IMX8MP_POWER_DOMAIN_MEDIAMIX_ISPDWP>;
>                                                 clocks = <&clk IMX8MP_CLK_MEDIA_ISP_ROOT>;
>                                         };
> +
> +                                       pgc_vpumix: power-domain@19 {
> +                                               #power-domain-cells = <0>;
> +                                               reg = <IMX8MP_POWER_DOMAIN_VPUMIX>;
> +                                               clocks =<&clk IMX8MP_CLK_VPU_ROOT>;
> +                                       };
> +
> +                                       pgc_vpu_g1: power-domain@20 {
> +                                               #power-domain-cells = <0>;
> +                                               power-domains = <&pgc_vpumix>;
> +                                               reg = <IMX8MP_POWER_DOMAIN_VPU_G1>;
> +                                               clocks = <&clk IMX8MP_CLK_VPU_G1_ROOT>;
> +                                       };
> +
> +                                       pgc_vpu_g2: power-domain@21 {
> +                                               #power-domain-cells = <0>;
> +                                               power-domains = <&pgc_vpumix>;
> +                                               reg = <IMX8MP_POWER_DOMAIN_VPU_G2>;
> +                                               clocks = <&clk IMX8MP_CLK_VPU_G2_ROOT>;
> +                                       };
> +
> +                                       pgc_vpu_vc8000e: power-domain@22 {
> +                                               #power-domain-cells = <0>;
> +                                               power-domains = <&pgc_vpumix>;
> +                                               reg = <IMX8MP_POWER_DOMAIN_VPU_VC8000E>;
> +                                               clocks = <&clk IMX8MP_CLK_VPU_VC8KE_ROOT>;
> +                                       };
>                                 };
>                         };
>                 };

This change causes new error messages to come out during boot, for example:

    ...
    imx-pgc imx-pgc-domain.8: failed to command PGC
    imx-pgc imx-pgc-domain.8: failed to command PGC
    imx-pgc imx-pgc-domain.8: failed to command PGC
    30890000.serial: ttymxc1 at MMIO 0x30890000 (irq = 197, base_baud = 1500000) is a IMX
    ...
    hwmon hwmon1: temp1_input not attached to any thermal zone
    imx-pgc imx-pgc-domain.8: failed to command PGC
    imx-pgc imx-pgc-domain.8: failed to command PGC
    imx-pgc imx-pgc-domain.8: failed to command PGC
    ...

They don't seem to cause any problems on the hardware I am using, well,
at least not that I have found so far.

This first appeared for me in linux-6.1. But it is the same in todays
linux 6.3-rc4. Reverting this change (not completely trivial due to a
couple of commits after it that rely on it) fixes it - no more errors.

Regards
Greg