From 71893eb2f68d8dd59d462be73e9832ccb4ccfe9d Mon Sep 17 00:00:00 2001 From: "Justin M. Forbes" Date: Tue, 21 Apr 2020 08:43:50 -0500 Subject: Linux v5.6.6 rebase --- ...-gr-gp107-gp108-implement-workaround-for-.patch | 68 ++++++++++++++++++++++ 1 file changed, 68 insertions(+) create mode 100644 0002-drm-nouveau-gr-gp107-gp108-implement-workaround-for-.patch (limited to '0002-drm-nouveau-gr-gp107-gp108-implement-workaround-for-.patch') diff --git a/0002-drm-nouveau-gr-gp107-gp108-implement-workaround-for-.patch b/0002-drm-nouveau-gr-gp107-gp108-implement-workaround-for-.patch new file mode 100644 index 000000000..554800010 --- /dev/null +++ b/0002-drm-nouveau-gr-gp107-gp108-implement-workaround-for-.patch @@ -0,0 +1,68 @@ +From 37b556606d1217b4367e622d88cef11c65764386 Mon Sep 17 00:00:00 2001 +From: Ben Skeggs +Date: Tue, 31 Mar 2020 16:08:44 +1000 +Subject: [PATCH 2/2] drm/nouveau/gr/gp107,gp108: implement workaround for HW + hanging during init + +Certain boards with GP107/GP108 chipsets hang (often, but randomly) for +unknown reasons during GR initialisation. + +The first tell-tale symptom of this issue is: + +nouveau 0000:01:00.0: bus: MMIO read of 00000000 FAULT at 409800 [ TIMEOUT ] + +appearing in dmesg, likely followed by many other failures being logged. + +Karol found this WAR for the issue a while back, but efforts to isolate +the root cause and proper fix have not yielded success so far. I've +modified the original patch to include a few more details, limit it to +GP107/GP108 by default, and added a config option to override this choice. + +Signed-off-by: Ben Skeggs +Reviewed-by: Karol Herbst +--- + .../gpu/drm/nouveau/nvkm/engine/gr/gf100.c | 26 +++++++++++++++++++ + 1 file changed, 26 insertions(+) + +diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/gr/gf100.c b/drivers/gpu/drm/nouveau/nvkm/engine/gr/gf100.c +index dd8f85b8b3a7..f2f5636efac4 100644 +--- a/drivers/gpu/drm/nouveau/nvkm/engine/gr/gf100.c ++++ b/drivers/gpu/drm/nouveau/nvkm/engine/gr/gf100.c +@@ -1981,8 +1981,34 @@ gf100_gr_init_(struct nvkm_gr *base) + { + struct gf100_gr *gr = gf100_gr(base); + struct nvkm_subdev *subdev = &base->engine.subdev; ++ struct nvkm_device *device = subdev->device; ++ bool reset = device->chipset == 0x137 || device->chipset == 0x138; + u32 ret; + ++ /* On certain GP107/GP108 boards, we trigger a weird issue where ++ * GR will stop responding to PRI accesses after we've asked the ++ * SEC2 RTOS to boot the GR falcons. This happens with far more ++ * frequency when cold-booting a board (ie. returning from D3). ++ * ++ * The root cause for this is not known and has proven difficult ++ * to isolate, with many avenues being dead-ends. ++ * ++ * A workaround was discovered by Karol, whereby putting GR into ++ * reset for an extended period right before initialisation ++ * prevents the problem from occuring. ++ * ++ * XXX: As RM does not require any such workaround, this is more ++ * of a hack than a true fix. ++ */ ++ reset = nvkm_boolopt(device->cfgopt, "NvGrResetWar", reset); ++ if (reset) { ++ nvkm_mask(device, 0x000200, 0x00001000, 0x00000000); ++ nvkm_rd32(device, 0x000200); ++ msleep(50); ++ nvkm_mask(device, 0x000200, 0x00001000, 0x00001000); ++ nvkm_rd32(device, 0x000200); ++ } ++ + nvkm_pmu_pgob(gr->base.engine.subdev.device->pmu, false); + + ret = nvkm_falcon_get(&gr->fecs.falcon, subdev); +-- +2.25.1 + -- cgit