[PATCH v4 0/5] powervr: MT8173 GPU support

Tue Jul 28 17:08:40 PDT 2026

Hi Chen-Yu,

Thank you for posting the v4 series.

I tested the complete v4 series on my MT8173 Chromebook, but I am
seeing a GPU device loss as soon as Mesa initializes the Vulkan device.

My current setup is:

  Board: Google Elm / Acer Chromebook R13 (CB5-312T)
  Kernel:
    linux-next next-20260727
    commit: 33d6e5134c70446eddafbb3fd5ad088e848a7ad6
    (next-20260727-5-g33d6e5134c70)

  Kernel release: 7.2.0-rc5-next-20260727-stb-cbm-next-pvr-v4+

  Mesa: 26.1.5
  vulkan-powervr: 26.1.5
  Firmware:
    rogue_4.40.2.51_v1.fw
    SHA256:
    f44b7056992fb4057c987dcd7073468bec628aa56cb9815b1162f1cb7c1d73f2

All five patches applied cleanly. The PowerVR driver probes, loads the
firmware, and creates the DRM render node successfully.

However, when I run the following from an SSH session without GDM or
another graphical session running:

  PVR_I_WANT_A_BROKEN_VULKAN_DRIVER=1 vulkaninfo --summary

Mesa prints the expected GX6250 warnings:

  Missing reset support for brn51764
  Missing reset support for brn58839
  Missing support for brn62269

The command then hangs, and the kernel reports:

  powervr 13000000.gpu: [drm] *ERROR* GPU device lost

There are no additional timeout, MMU fault, firmware, clock, or runtime
PM messages immediately before the device-lost message.

I originally also observed the same failure when GDM started GNOME
Shell, but reproducing it with vulkaninfo from a non-graphical SSH
session indicates that this is not specific to Mutter or GNOME.

Since your cover letter reports that vkmark and glmark2-es2-drm work
with Mesa 26.1.5, I suspect that there may be a difference in the
kernel configuration or another part of the test environment.

Could you please share the following details from your working setup?

  1. The exact Chromebook board/model used for testing
  2. The exact kernel base commit
  3. The kernel configuration, or at least the relevant DRM, PM,
     generic power-domain, IOMMU, and MediaTek clock options
  4. Whether CONFIG_DRM_POWERVR was built-in or built as a module
  5. The firmware SHA256
  6. The kernel command line and bootloader used
  7. Whether `vulkaninfo --summary` also completes successfully

My current relevant configuration includes:

CONFIG_PM_SLEEP=y
CONFIG_PM=y
CONFIG_PM_GENERIC_DOMAINS=y
CONFIG_MODULES=y
CONFIG_DMA_SHARED_BUFFER=y
CONFIG_DRM_POWERVR=m
CONFIG_DRM_MEDIATEK=y
CONFIG_SYNC_FILE=y
CONFIG_COMMON_CLK_MT8173_MFGTOP=y
CONFIG_IOMMU_SUPPORT=y
CONFIG_ARM_SMMU=y
CONFIG_MTK_IOMMU=y

I would be happy to test additional patches or provide any further
logs, kernel configuration, or debugging information if that would
help.

Thanks,
YoungJoon Lee

2026年7月29日(水) 0:28 AngeloGioacchino Del Regno
<angelogioacchino.delregno at collabora.com>:
>
> On 7/28/26 16:44, Chen-Yu Tsai wrote:
> > On Tue, Jul 28, 2026 at 10:33 PM AngeloGioacchino Del Regno
> > <angelogioacchino.delregno at collabora.com> wrote:
> >>
> >> On 7/28/26 15:13, Chen-Yu Tsai wrote:
> >>> On Tue, Jul 28, 2026 at 9:10 PM Brian Masney <bmasney at redhat.com> wrote:
> >>>>
> >>>> Hi Chen-Yu,
> >>>>
> >>>> On Tue, Jul 28, 2026 at 05:17:58PM +0800, Chen-Yu Tsai wrote:
> >>>>> Hi everyone,
> >>>>>
> >>>>> This is v4 of my MT8173 PowerVR GPU support series.
> >>>>>
> >>>>> This time around Mesa was ready for basic testing, using both vulkanmark
> >>>>> and glmark2-es2-drm (with Zink). Details below.
> >>>>>
> >>>>> Changes since v3 (all in the clk driver patch):
> >>>>> - Changed pm_runtime_put() to pm_runtime_put_sync()
> >>>>> - Added missing of_node_put() in remove function
> >>>>>
> >>>>> Changes since v2 (all in the clk driver patch):
> >>>>> - Made COMMON_CLK_MT8173_MFGTOP depend on PM
> >>>>>     - Needed since the driver implements PM domains using the generic PM
> >>>>>       domain library, which also depends on PM
> >>>>>     - Fixes build breakage (kernel test robot)
> >>>>> - Fixed "RST_DELAY_CNT" name (Brian)
> >>>>> - Dropped unused mfg_desc (Brian)
> >>>>> - Added check of clk_prepare_enable()'s return value in
> >>>>>     clk_mt8173_mfgtop_power_on() (Brian)
> >>>>> - Saved error value for return in IS_ERR(data->clk_26m) branch
> >>>>>     (Dan Carpenter / kernel test robot w/ smatch)
> >>>>>
> >>>>> Changes since v1:
> >>>>> - Adapted to changed DT bindings
> >>>>> - Dropped driver change
> >>>>> - Use same power domain for "a" and "b" GPU power domains
> >>>>>
> >>>>>
> >>>>> This series enables the PowerVR GPU found in the MT8173 SoC, found in
> >>>>> some Chromebooks.
> >>>>
> >>>> I'm making a pull for Stephen for the clk changes. Should patches 1,2,4
> >>>> go through the clk tree? Patches 3,5 go through the DRM tree?
> >>>
> >>> Only patches 1 and 2 should go through the clock tree.
> >>>
> >>> Patch 3, 4, 5 can all go through the soc tree if Angelo wants to pick up
> >>> DT binding patches. Otherwise I can push patch 3 through drm-misc.
> >>>
> >>
> >> Not sure if I can really take the DRM bindings patch through soc.
> >>
> >> I will take the devicetree ones exactly right now, even though it's going to
> >> give warnings.
> >>
> >> I trust that you'll make the binding get into linux-next before it's too late.
> >
> > Rob beat me to it. :D
>
> Love it!
>
> Thanks Rob :-D
>
> Cheers,
> Angelo