Re: [PATCH v2 00/10] drm: Add driver for PowerPC OF displays
Hello, On Thu, Jul 28, 2022 at 09:13:59PM +1000, Michael Ellerman wrote: > Thomas Zimmermann writes: > > (was: drm: Add driverof PowerPC OF displays) > > > > PowerPC's Open Firmware offers a simple display buffer for graphics > > output. Add ofdrm, a DRM driver for the device. As with the existing > > simpledrm driver, the graphics hardware is pre-initialized by the > > firmware. The driver only provides blitting, no actual DRM modesetting > > is possible. > > Hi Thomas, > > I tried to test this on a 32-bit ppc Mac Mini but didn't have much luck. > But I'm probably doing something wrong because I'm a graphics noob. > > The machine normally uses CONFIG_DRM_RADEON, so I turned that off, and > turned DRM_OFDRM on. > > When I boot I get boot messages but only one screen worth, the messages > don't scroll at all, which is unusual. But I'm not sure if that's > related to ofdrm or something else. A somewhat interesting datapoint might be how this works with offb. > The machine does come up, I can login via SSH. Is there some way to > start X to exercise the driver from an SSH login? The startx script provided by distribution usually works. It's basically a very convoluted way to do something like X :0& DISPLAY=:0 xterm& Thanks Michal
Re: [PATCH v2 00/10] drm: Add driver for PowerPC OF displays
Thomas Zimmermann writes: > (was: drm: Add driverof PowerPC OF displays) > > PowerPC's Open Firmware offers a simple display buffer for graphics > output. Add ofdrm, a DRM driver for the device. As with the existing > simpledrm driver, the graphics hardware is pre-initialized by the > firmware. The driver only provides blitting, no actual DRM modesetting > is possible. Hi Thomas, I tried to test this on a 32-bit ppc Mac Mini but didn't have much luck. But I'm probably doing something wrong because I'm a graphics noob. The machine normally uses CONFIG_DRM_RADEON, so I turned that off, and turned DRM_OFDRM on. When I boot I get boot messages but only one screen worth, the messages don't scroll at all, which is unusual. But I'm not sure if that's related to ofdrm or something else. The machine does come up, I can login via SSH. Is there some way to start X to exercise the driver from an SSH login? cheers
[PATCH v2 00/10] drm: Add driver for PowerPC OF displays
(was: drm: Add driverof PowerPC OF displays) PowerPC's Open Firmware offers a simple display buffer for graphics output. Add ofdrm, a DRM driver for the device. As with the existing simpledrm driver, the graphics hardware is pre-initialized by the firmware. The driver only provides blitting, no actual DRM modesetting is possible. Version 2 of this patchset starts by cleaning up and refactoring simpledrm, and moving some of the code in a helper library. These functions are useful for ofdrm as well. Patch 7 adds ofdrm, which has been significantly reworked since v1. PCI is now optional and COMPILE_TEST is supported. Patches 8 to 10 add support for color management. The code has been taken from fbdev's offb. I have no hardware available for testing the functionality. Qemu's stdvga apparently does not support gamma tables in RGB modes. I verified that the color management code is executed by running Gnome's night-mode settings, but the display's color tone does not change. Thomas Zimmermann (10): drm/simpledrm: Remove mem field from device structure drm/simpledrm: Inline device-init helpers drm/simpledrm: Remove pdev field from device structure drm/simpledrm: Compute framebuffer stride if not set drm/simpledrm: Convert to atomic helpers drm/simpledrm: Move some functionality into fwfb helper library drm/ofdrm: Add ofdrm for Open Firmware framebuffers drm/ofdrm: Add CRTC state drm/ofdrm: Add per-model device function drm/ofdrm: Support color management Documentation/gpu/drm-kms-helpers.rst | 12 + MAINTAINERS |3 + drivers/gpu/drm/Kconfig |6 + drivers/gpu/drm/Makefile |3 +- drivers/gpu/drm/drm_fwfb_helper.c | 301 ++ drivers/gpu/drm/tiny/Kconfig | 15 + drivers/gpu/drm/tiny/Makefile |1 + drivers/gpu/drm/tiny/ofdrm.c | 1301 + drivers/gpu/drm/tiny/simpledrm.c | 588 +-- drivers/video/fbdev/Kconfig |1 + include/drm/drm_fwfb_helper.h | 51 + 11 files changed, 1949 insertions(+), 333 deletions(-) create mode 100644 drivers/gpu/drm/drm_fwfb_helper.c create mode 100644 drivers/gpu/drm/tiny/ofdrm.c create mode 100644 include/drm/drm_fwfb_helper.h -- 2.36.1
