[PATCH 4.19 18/34] Revert "drm/nouveau/pmu/gm200-: avoid touching PMU outside of DEVINIT/PREOS/ACR"

Greg Kroah-Hartman
2022-02-28T17:34:34Z

From: Karol Herbst <kherbst@redhat.com>

This reverts commit c9ec3d85c0eef7c71cdc68db758e0f0e378132c0.

This commit causes a regression if 4cdd2450bf739bada353e82d27b00db9af8c3001
is not applied as well. This was fixed for 5.16, 5.15 and 5.10.

On older stable branches backporting this commit is complicated as relevant
code changed quite a bit. Furthermore most of the affected hardware barely
works on those and users would want to use the newer kernels anyway.

Cc: stable@vger.kernel.org # 5.4 4.19 and 4.14
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Lyude Paul <lyude@redhat.com>
Link: https://gitlab.freedesktop.org/drm/nouveau/-/issues/149
Signed-off-by: Karol Herbst <kherbst@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/gpu/drm/nouveau/nvkm/subdev/pmu/base.c | 37 ++++++++++---------------
1 file changed, 16 insertions(+), 21 deletions(-)

--- a/drivers/gpu/drm/nouveau/nvkm/subdev/pmu/base.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/pmu/base.c
@@ -70,13 +70,20 @@ nvkm_pmu_fini(struct nvkm_subdev *subdev
return 0;
}

-static void
+static int
nvkm_pmu_reset(struct nvkm_pmu *pmu)
{
struct nvkm_device *device = pmu->subdev.device;

if (!pmu->func->enabled(pmu))
- return;
+ return 0;
+
+ /* Inhibit interrupts, and wait for idle. */
+ nvkm_wr32(device, 0x10a014, 0x0000ffff);
+ nvkm_msec(device, 2000,
+ if (!nvkm_rd32(device, 0x10a04c))
+ break;
+ );

/* Reset. */
if (pmu->func->reset)
@@ -87,37 +94,25 @@ nvkm_pmu_reset(struct nvkm_pmu *pmu)
if (!(nvkm_rd32(device, 0x10a10c) & 0x00000006))
break;
);
+
+ return 0;
}

static int
nvkm_pmu_preinit(struct nvkm_subdev *subdev)
{
struct nvkm_pmu *pmu = nvkm_pmu(subdev);
- nvkm_pmu_reset(pmu);
- return 0;
+ return nvkm_pmu_reset(pmu);
}

static int
nvkm_pmu_init(struct nvkm_subdev *subdev)
{
struct nvkm_pmu *pmu = nvkm_pmu(subdev);
- struct nvkm_device *device = pmu->subdev.device;
-
- if (!pmu->func->init)
- return 0;
-
- if (pmu->func->enabled(pmu)) {
- /* Inhibit interrupts, and wait for idle. */
- nvkm_wr32(device, 0x10a014, 0x0000ffff);
- nvkm_msec(device, 2000,
- if (!nvkm_rd32(device, 0x10a04c))
- break;
- );
-
- nvkm_pmu_reset(pmu);
- }
-
- return pmu->func->init(pmu);
+ int ret = nvkm_pmu_reset(pmu);
+ if (ret == 0 && pmu->func->init)
+ ret = pmu->func->init(pmu);
+ return ret;
}

static int