On 18 April 2018 at 00:14, Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx> wrote: > Quoting Jani Nikula (2018-04-17 12:02:52) >> On Mon, 16 Apr 2018, "Srivatsa, Anusha" <anusha.srivatsa@xxxxxxxxx> wrote: >> >>-----Original Message----- >> >>From: Jani Nikula [mailto:jani.nikula@xxxxxxxxxxxxxxx] >> >>Sent: Wednesday, April 11, 2018 5:27 AM >> >>To: Ian W MORRISON <ianwmorrison@xxxxxxxxx> >> >>Cc: Vivi, Rodrigo <rodrigo.vivi@xxxxxxxxx>; Srivatsa, Anusha >> >><anusha.srivatsa@xxxxxxxxx>; Wajdeczko, Michal >> >><Michal.Wajdeczko@xxxxxxxxx>; Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>; >> >>airlied@xxxxxxxx; joonas.lahtinen@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; >> >>stable@xxxxxxxxxxxxxxx; intel-gfx@xxxxxxxxxxxxxxxxxxxxx; dri- >> >>devel@xxxxxxxxxxxxxxxxxxxxx >> >>Subject: Re: [RESEND PATCH 1/1] drm/i915/glk: Add MODULE_FIRMWARE for >> >>Geminilake <snip> In summary so far: Jani: > NAK on indiscriminate Cc: stable. There are zero guarantees that > older kernels will work with whatever firmware you throw at them. > Who tested the firmware with v4.12 and later? We only have the CI > results against *current* drm-tip. We don't even know about v4.16. > I'm not going to ack and take responsibility for the stable backports > unless someone actually comes forward with credible Tested-bys. Anusha: > The stable kernel version is 4.12 and beyond. > It is appropriate to add the CC: stable in my opinion Joonas: > And even then, some distros will be surprised of the new MODULE_FIRMWARE > and will need to update the linux-firmware package, too. I've performed backport testing and some additional analysis as follows: The DMC firmware for GLK was initially included in 4.11 (commit: dbb28b5c3d3cb945a63030fab8d3894cf335ce19). Then the firmware version was upgraded to 1.03 in 4.12 (commit: f4a791819ed00a749a90387aa139706a507aa690). However MODULE_FIRMWARE for the GLK DMC firmware was also removed in 4.12 (commit: d9321a03efcda867b3a8c6327e01808516f0acd7) together with the firmware version being bumped to 1.04 (commit: aebfd1d37194e00d4c417e7be97efeb736cd9c04). The patch below effectively reverts commit d9321a03 because the GLK firmware is now available in the linux-firmware repository. To test stable backports I've used Ubuntu 18.04 (Beta 2) userspace with both Ubuntu (generic) and self-compiled mainline (patched) kernels. The conclusion was that the patch works across 4.12 to 4.17-rc1 kernels additionally displaying a 'Possible missing firmware' message when installing a kernel with the expected firmware missing. The following are abridged backport test results: Scenario: No DMC (glk_dmc_ver1_04.bin) firmware installed in '/lib/firmware/i915' Test:Kernel installation ('grep -i dmc' output from 'apt install'): 4.12-generic and 4.15-generic: No output # as expected 4.12 to 4.17-rc1-patched: W: Possible missing firmware /lib/firmware/i915/glk_dmc_ver1_04.bin for module i915 Result: The effect of the patch is to add a 'Possible missing firmware' message. Test: Booting ('grep -i dmc' output from 'dmesg'): 4.12-generic: No output # as expected 4.15-generic: i915 0000:00:02.0: Direct firmware load for i915/glk_dmc_ver1_04.bin failed with error -2 i915 0000:00:02.0: Failed to load DMC firmware i915/glk_dmc_ver1_04.bin. Disabling runtime power management. i915 0000:00:02.0: DMC firmware homepage: https://01.org/linuxgraphics/downloads/firmware 4.12-patched: No output # as expected 4.13 to 4.14-patched: i915 0000:00:02.0: Direct firmware load for i915/glk_dmc_ver1_04.bin failed with error -2 i915 0000:00:02.0: Failed to load DMC firmware [https://01.org/linuxgraphics/downloads/firmware], disabling runtime power management. 4.15 to 4.17-rc1-patched: i915 0000:00:02.0: Direct firmware load for i915/glk_dmc_ver1_04.bin failed with error -2 i915 0000:00:02.0: Failed to load DMC firmware i915/glk_dmc_ver1_04.bin. Disabling runtime power management. i915 0000:00:02.0: DMC firmware homepage: https://01.org/linuxgraphics/downloads/firmware Result: The effect of the patch does not change existing (non-patched kernel) messages. Scenario: DMC (glk_dmc_ver1_04.bin) firmware installed in '/lib/firmware/i915' Test:Kernel installation ('grep -i dmc' output from 'apt install') All kernels: No messages # as expected Result: The effect of the patch does not change existing messages. Test" Booting ('grep -i dmc' output from 'dmesg'): 4.12-generic: No output # as expected 4.15-generic: i915 0000:00:02.0: Direct firmware load for i915/glk_dmc_ver1_04.bin failed with error -2 i915 0000:00:02.0: Failed to load DMC firmware i915/glk_dmc_ver1_04.bin. Disabling runtime power management. i915 0000:00:02.0: DMC firmware homepage: https://01.org/linuxgraphics/downloads/firmware 4.12-patched: No output # as expected 4.13 to 4.17-rc1-patched: [drm] Finished loading DMC firmware i915/glk_dmc_ver1_04.bin (v1.4) Result: The effect of the patch is to remove the 'Failed to load' message. Regards, Ian _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
