在 2026-07-28二的 15:29 +0900，YoungJoon Lee写道： > Hello, > > I am testing the upstream Mesa PowerVR Vulkan driver and Linux > PowerVR > DRM driver on a Google Elm Chromebook with a MediaTek MT8173 SoC and > a > PowerVR Rogue GX6250 GPU. > > I can reliably reproduce a GPU device loss and permanent process hang > using vulkaninfo in a clean console-only environment, without GNOME, > GDM, Mutter, or another graphics application running. > > System information: > > Device: Google Elm Chromebook > SoC: MediaTek MT8173 > GPU: PowerVR Rogue GX6250 > Architecture: aarch64 > Distribution: Arch Linux ARM > Kernel: Linux 7.1.3-stb-cbm-pvr-v3 > Mesa: 26.1.5 > Firmware: powervr/rogue_4.40.2.51_v1.fw > Kernel parameter: powervr.exp_hw_support=1 > Vulkan ICD: /usr/share/vulkan/icd.d/powervr_mesa_icd.json > Vulkan library: /usr/lib/libvulkan_powervr_mesa.so > > The kernel driver and firmware initially load successfully: > > powervr 13000000.gpu: [drm] Running on unknown hardware; expect > issues. > powervr 13000000.gpu: [drm] loaded firmware > powervr/rogue_4.40.2.51_v1.fw > powervr 13000000.gpu: [drm] FW version v1.0 (build 6476056 OS) > [drm] Initialized powervr 1.0.0 for 13000000.gpu on minor 1 > > I then run: > > env > PVR_I_WANT_A_BROKEN_VULKAN_DRIVER=1 > VK_DRIVER_FILES=/usr/share/vulkan/icd.d/powervr_mesa_icd.json > VK_LOADER_DEBUG=all > LD_BIND_NOW=1 > vulkaninfo --summary > > The Vulkan loader successfully detects the physical device: > > Original order: > [0] PowerVR Rogue GX6250 > Sorted order: > [0] PowerVR Rogue GX6250 > > It then reaches the device-creation path: > > vkCreateDevice layer callstack setup to: > <Application> > > > > <Loader> > > > > <Device> > Using "PowerVR Rogue GX6250" with driver: > "/usr/lib/libvulkan_powervr_mesa.so" > > Immediately afterward, Mesa prints: > > MESA: warning: pvr_arch_job_context.c:73: > FINISHME: Missing reset support for brn51764 > > MESA: warning: pvr_arch_job_context.c:76: > FINISHME: Missing reset support for brn58839 > > MESA: warning: pvr_arch_job_context.c:523: > FINISHME: Missing support for brn62269 > > MESA: warning: pvr_arch_border.c:244: > FINISHME: Devices without tpu_border_colour_enhanced require entries > for compressed formats to be stored in the table pre-compressed. > > Approximately two seconds after starting vulkaninfo, the kernel > reports: > > powervr 13000000.gpu: [drm] ERROR GPU device lost
I remember seeing this because of the runtime power management of drm/imagination is broken on GX6250. Could you set the power/control file in the device's sysfs to "on" (instead of the default "auto") to disable runpm and re-check? I remember that another error may appear in such case but the GPU won't be lost. (However I am on vacation and my MT8173 machine isn't with me so I cannot provide more information.) Thanks, Icenowy > > vulkaninfo does not return. It remains in uninterruptible sleep: > > PID PPID STAT WCHAN CMD > 526 434 Dl+ synchronize_srcu vulkaninfo --summary > > /proc/526/status: > State: D (disk sleep) > > /proc/526/wchan: > __synchronize_srcu > > The current syscall is ioctl, and vulkaninfo is the only process > holding /dev/dri/renderD128. > > The blocked process has this kernel stack: > > __synchronize_srcu > synchronize_srcu > drm_dev_unplug > pvr_power_reset > pvr_mmu_flush_exec > pvr_mmu_op_context_destroy > pvr_vm_bind_op_fini > pvr_vm_unmap_obj_locked > pvr_vm_unmap > pvr_ioctl_vm_unmap > drm_ioctl_kernel > drm_ioctl > __arm64_sys_ioctl > invoke_syscall > el0_svc_common > do_el0_svc > el0_svc > > The observed sequence is therefore: > > The PowerVR kernel driver and firmware initialize successfully. > vkCreateInstance succeeds. > Physical-device enumeration succeeds and reports the GX6250. > Execution reaches vkCreateDevice. > The kernel reports GPU device lost. > The process enters the PVR VM-unmap/reset cleanup path. > It hangs indefinitely in drm_dev_unplug -> synchronize_srcu. > > This appears to expose two related issues: > > GPU device loss during Vulkan device creation. > A permanent kernel hang in the device-loss cleanup/reset path. > > I am not assuming that the FINISHME messages for brn51764, brn58839, > brn62269, or the border-colour path are necessarily the direct cause. > I included them because they are the final Mesa messages printed > immediately before the failure. > > Could you please advise whether the GX6250 hardware revision used by > MT8173 is expected to work with the current experimental driver, and > whether this should primarily be reported against Mesa, the Linux > PowerVR DRM driver, or both? > > I can provide the complete logs or run a minimal Vulkan reproducer > that separately records vkCreateInstance, vkEnumeratePhysicalDevices, > and vkCreateDevice if that would be useful. > > Best regards, > > YoungJoon Lee > > 2026年7月28日(火) 0:48 YoungJoon Lee <[email protected]>: > > > > Hello, > > > > I tested patches 1/5 through 5/5 from the MT8173 PowerVR v3 series > > on > > an Acer Chromebook R13 (Google Elm), which uses an MT8173 SoC and a > > PowerVR Rogue GX6250 GPU with BVNC 4.40.2.51. > > > > For clarity, I applied the five actual patches numbered 1/5 through > > 5/5. The 0/5 cover letter itself was not applied. > > > > Kernel: > > Linux 7.1.3-stb-cbm-pvr-v3 > > > > Relevant kernel configuration: > > CONFIG_DRM_POWERVR=m > > CONFIG_COMMON_CLK_MT8173_MFGTOP=y > > > > Kernel command line: > > powervr.exp_hw_support=1 > > > > Firmware: > > powervr/rogue_4.40.2.51_v1.fw > > > > The driver probes successfully, loads the firmware, and initializes > > the > > DRM device: > > > > [ 6.110569] powervr 13000000.gpu: > > [drm] Running on unknown hardware; expect issues. > > [ 6.117454] powervr 13000000.gpu: > > [drm] loaded firmware > > powervr/rogue_4.40.2.51_v1.fw > > [ 6.118010] powervr 13000000.gpu: > > [drm] FW version v1.0 (build 6476056 OS) > > [ 6.122992] [drm] Initialized powervr 1.0.0 > > for 13000000.gpu on minor 1 > > > > The following DRM device nodes are created: > > > > /dev/dri/card0 > > /dev/dri/card1 > > /dev/dri/renderD128 > > > > However, on a clean boot, without manually running vulkaninfo, > > vkcube, > > or another Vulkan application, the driver reports that the GPU has > > been > > lost approximately six seconds after DRM initialization: > > > > [ 12.084078] powervr 13000000.gpu: > > [drm] *ERROR* GPU device lost > > > > The relevant boot sequence is therefore: > > > > [ 6.110569] PowerVR probe begins > > [ 6.117454] Firmware is loaded > > [ 6.118010] Firmware version is reported > > [ 6.122992] DRM initialization completes > > [ 12.084078] GPU device lost > > > > The unused-regulator shutdown occurs considerably later: > > > > [ 31.712124] vgpu: disabling > > > > Therefore, the later "vgpu: disabling" message does not appear to > > be > > the immediate cause of the device loss. The GPU is reported lost > > about > > 20 seconds before that regulator shutdown message. > > > > After the failure, regulator_summary reports: > > > > vgpu 0 0 0 normal 1000mV 0mA 700mV 1350mV > > > > This output was collected after the GPU had already been reported > > lost, > > so I do not know whether the regulator state was different during > > probe > > or immediately before the failure. > > > > The PowerVR-related clocks appear enabled in clk_summary: > > > > mfg_26m 26000000 Hz > > > > mem_mfg_in_sel > > rate: 455000000 Hz > > enable: 1 > > prepare: 1 > > > > mfg_mem > > rate: 455000000 Hz > > enable: 1 > > prepare: 1 > > consumer: 13000000.gpu > > clock name: mem > > > > mfg_sel > > rate: 455000000 Hz > > enable: 1 > > prepare: 1 > > > > mfg_g3d > > rate: 455000000 Hz > > enable: 1 > > prepare: 1 > > consumer: 13000000.gpu > > clock name: core > > > > axi_mfg_in_sel > > rate: 208000000 Hz > > enable: 2 > > prepare: 2 > > consumer: power-domain@7 > > > > mfg_axi > > rate: 208000000 Hz > > enable: 1 > > prepare: 1 > > consumer: 13000000.gpu > > clock name: sys > > > > I also installed Mesa 26.1.5 and vulkan-powervr 26.1.5 and tested > > the > > Vulkan ICD with: > > > > PVR_I_WANT_A_BROKEN_VULKAN_DRIVER=1 \ > > VK_DRIVER_FILES=/usr/share/vulkan/icd.d/powervr_mesa_icd.json \ > > vulkaninfo --summary > > > > The PowerVR ICD was found and loaded. Before hanging, Mesa printed: > > > > WARNING: powervr is not a conformant Vulkan implementation, > > testing use only. > > > > FINISHME: Missing reset support for brn51764 > > FINISHME: Missing reset support for brn58839 > > FINISHME: Missing support for brn62269 > > FINISHME: Devices without tpu_border_colour_enhanced require > > entries > > for compressed formats to be stored in the table > > pre-compressed. > > > > The vulkaninfo process then remained in uninterruptible sleep: > > > > PID STAT WCHAN COMMAND > > 3244 Dl+ synchronize_srcu vulkaninfo --summary > > > > It could not be terminated normally while in that state, and a > > reboot > > was required. > > > > However, the clean-boot log shows that "GPU device lost" occurs > > even > > without starting vulkaninfo manually. The vulkaninfo hang may > > therefore > > be a consequence of the GPU already being in the lost state, rather > > than > > the original cause of the failure. > > > > At this point, the following parts appear to work: > > > > - MT8173 GPU device-tree node probing > > - MFGTOP clock registration > > - PowerVR kernel module probing > > - Firmware loading > > - Firmware version reporting > > - DRM device initialization > > - Creation of card1 and renderD128 > > > > The remaining problem is that the GPU becomes lost approximately > > six > > seconds after initialization. > > > > Could this be related to an interrupt not being delivered, firmware > > heartbeat handling, reset sequencing, runtime PM, a missing > > regulator > > consumer relationship, or another MT8173-specific power-domain > > requirement? > > > > Please let me know which additional kernel debug options, DRM debug > > settings, tracepoints, interrupt statistics, register dumps, or > > test > > patches would be useful. I have physical access to the device and > > can > > build and test further kernel changes. > > > > Thank you for working on MT8173 support. > > > > Best regards, > > YoungJoon Lee > > > > 2026年7月27日(月) 18:16 Chen-Yu Tsai <[email protected]>: > > > > > > Hi everyone, > > > > > > This is v3 of my MT8173 PowerVR GPU support series. > > > > > > I got another inquiry on the status of this patch series, so I > > > thought > > > I'd dig it out, fix all the issues and send another version. > > > > > > This time around Mesa was ready for basic testing, using both > > > vulkanmark > > > and glmark2-es2-drm (with Zink). Details below. > > > > > > 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. > > > > > > This version is different from the initial powervr driver > > > submission [1] > > > in that it splits out the GPU glue layer support out of the > > > powervr > > > driver and into a separate clock and power domain driver. The > > > glue code > > > is otherwise the same, and also the same as found in the ChromeOS > > > kernels, with some extra comments and macro names added where > > > possible. > > > > > > Patch 1 adds a binding for the glue layer, called mfgtop. The > > > glue layer > > > contains clock and power controls for the GPU. > > > > > > Patch 2 adds a driver for the glue layer, implemented as a clock > > > driver > > > that also provides power domains. > > > > > > Patch 3 adds an entry for the MT8173 GPU and 6XT series to the > > > PowerVR > > > binding. > > > > > > Patch 4 corrects the clock for the GPU (called MFG) power domain. > > > > > > Patch 5 adds device nodes for the GPU and glue layer to the > > > MT8173 dtsi > > > file. > > > > > > The kernel driver successfully probes the hardware and loads the > > > "rogue_4.40.2.51_v1.fw" firmware provided by Imagination > > > Technologies [2]. > > > The "exp_hw_support" module parameter needs to be set for the > > > driver to > > > probe successfully. > > > > > > This was tested with Mesa 26.1.5 from Debian Forky. With this > > > version > > > vkmark and glmark2-es2 (over Zink) both run fine. Mesa spits out > > > a bunch > > > of warnings since the GX6250 core is not officially supported. > > > > > > # PVR_I_WANT_A_BROKEN_VULKAN_DRIVER=1 vkmark > > > WARNING: powervr is not a conformant Vulkan implementation, > > > testing use only. > > > WARNING: powervr is not a conformant Vulkan implementation, > > > testing use only. > > > MESA: warning: > > > ../src/imagination/vulkan/pvr_arch_job_context.c:73: FINISHME: > > > Missing reset support for brn51764 > > > MESA: warning: > > > ../src/imagination/vulkan/pvr_arch_job_context.c:76: FINISHME: > > > Missing reset support for brn58839 > > > MESA: warning: > > > ../src/imagination/vulkan/pvr_arch_job_context.c:523: FINISHME: > > > Missing support for brn62269 > > > MESA: warning: > > > ../src/imagination/vulkan/pvr_arch_border.c:244: FINISHME: > > > Devices without tpu_border_colour_enhanced require entries for > > > compressed formats to be stored in the table pre-compressed. > > > WARNING: powervr is not a conformant Vulkan implementation, > > > testing use only. > > > ======================================================= > > > vkmark 2025.01 > > > ======================================================= > > > Vendor ID: 0x1010 > > > Device ID: 0x6250 > > > Device Name: PowerVR Rogue GX6250 > > > Driver Version: 109056005 > > > Device UUID: d04cd6f3a25fd4900f89c151bccfdfcf > > > ======================================================= > > > [vertex] device-local=true: FPS: 251 FrameTime: 3.984 ms > > > [vertex] device-local=false: FPS: 220 FrameTime: 4.545 ms > > > [texture] anisotropy=0:^C FPS: 223 FrameTime: 4.484 ms > > > ======================================================= > > > vkmark Score: 231 > > > ======================================================= > > > > > > # PVR_I_WANT_A_BROKEN_VULKAN_DRIVER=1 glmark2-es2-drm > > > WARNING: powervr is not a conformant Vulkan implementation, > > > testing use only. > > > MESA: warning: > > > ../src/imagination/vulkan/pvr_arch_job_context.c:73: FINISHME: > > > Missing reset support for brn51764 > > > MESA: warning: > > > ../src/imagination/vulkan/pvr_arch_job_context.c:76: FINISHME: > > > Missing reset support for brn58839 > > > MESA: warning: > > > ../src/imagination/vulkan/pvr_arch_job_context.c:523: FINISHME: > > > Missing support for brn62269 > > > MESA: warning: > > > ../src/imagination/vulkan/pvr_arch_border.c:244: FINISHME: > > > Devices without tpu_border_colour_enhanced require entries for > > > compressed formats to be stored in the table pre-compressed. > > > Warning: DRM_CAP_ASYNC_PAGE_FLIP not supported, falling back > > > to 'mailbox' mode for SwapInterval(0). > > > ======================================================= > > > glmark2 2023.01 > > > ======================================================= > > > OpenGL Information > > > GL_VENDOR: Mesa > > > GL_RENDERER: zink Vulkan 1.2(PowerVR Rogue GX6250 > > > (IMAGINATION_OPEN_SOURCE_MESA)) > > > GL_VERSION: OpenGL ES 2.0 Mesa 26.1.5-1 > > > Surface Config: buf=32 r=8 g=8 b=8 a=8 depth=24 stencil=0 > > > samples=0 > > > Surface Size: 1366x768 fullscreen > > > ======================================================= > > > [build] use-vbo=false: FPS: 49 FrameTime: 20.473 ms > > > [build] use-vbo=true: FPS: 45 FrameTime: 22.660 ms > > > [texture] texture-filter=nearest: FPS: 45 FrameTime: 22.642 > > > ms > > > [texture] texture-filter=linear:^C FPS: 50 FrameTime: 20.172 > > > ms > > > ======================================================= > > > glmark2 Score: 46 > > > ======================================================= > > > > > > > > > Please have a look. > > > > > > Thanks > > > ChenYu > > > > > > [1] > > > https://lore.kernel.org/dri-devel/[email protected]/ > > > [2] > > > https://gitlab.freedesktop.org/imagination/linux-firmware/-/tree/powervr > > > > > > Chen-Yu Tsai (5): > > > dt-bindings: clock: mediatek: Add mt8173 mfgtop > > > clk: mediatek: Add mt8173-mfgtop driver > > > dt-bindings: gpu: powervr-rogue: Add MediaTek MT8173 GPU > > > arm64: dts: mediatek: mt8173: Fix MFG_ASYNC power domain clock > > > arm64: dts: mediatek: mt8173: Add GPU device nodes > > > > > > .../clock/mediatek,mt8173-mfgtop.yaml | 70 +++++ > > > .../bindings/gpu/img,powervr-rogue.yaml | 1 + > > > arch/arm64/boot/dts/mediatek/mt8173.dtsi | 33 ++- > > > drivers/clk/mediatek/Kconfig | 10 + > > > drivers/clk/mediatek/Makefile | 1 + > > > drivers/clk/mediatek/clk-mt8173-mfgtop.c | 241 > > > ++++++++++++++++++ > > > include/dt-bindings/clock/mt8173-clk.h | 7 + > > > 7 files changed, 362 insertions(+), 1 deletion(-) > > > create mode 100644 > > > Documentation/devicetree/bindings/clock/mediatek,mt8173- > > > mfgtop.yaml > > > create mode 100644 drivers/clk/mediatek/clk-mt8173-mfgtop.c > > > > > > -- > > > 2.55.0.229.g6434b31f56-goog > > >
