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

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

Hi Peng,

On 27/3/23 20:01, Peng Fan wrote:
>> Subject: Re: [PATCH] arm64: dts: imx8mp: add vpu pgc nodes
>>
>> 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.
> [Peng Fan]
> 
> The VPU BLK CTRL seems not enabled.

How to enable it?
I have the blk-ctrl config options enabled:

     #
     # i.MX SoC drivers
     #
     CONFIG_IMX_GPCV2_PM_DOMAINS=y
     CONFIG_SOC_IMX8M=y
     CONFIG_SOC_IMX9=y
     CONFIG_IMX8M_BLK_CTRL=y
     CONFIG_IMX9_BLK_CTRL=y
     # end of i.MX SoC drivers

Running with the full arm64 defconfig and using the imx8mp-evk.dtb still
outputs these messages:

     [   18.150679] imx-pgc imx-pgc-domain.8: failed to command PGC
     [   18.159241] imx-pgc imx-pgc-domain.8: failed to command PGC
     [   18.167822] imx-pgc imx-pgc-domain.8: failed to command PGC

Or do you mean something more fundamental, like the hardware block not
being enabled by boot loader?  (Something to keep in mind is that the
platform I am using has no video output, only serial console).

Regards
Greg