[PATCH v2] drm/nouveau: bring back blit subchannel for pre nv50 GPUs

Karol Herbst posted 1 patch 2 days, 11 hours ago
drivers/gpu/drm/nouveau/nouveau_chan.c |  1 +
drivers/gpu/drm/nouveau/nouveau_chan.h |  1 +
drivers/gpu/drm/nouveau/nouveau_drm.c  | 20 +++++++++++++++++---
3 files changed, 19 insertions(+), 3 deletions(-)
[PATCH v2] drm/nouveau: bring back blit subchannel for pre nv50 GPUs
Posted by Karol Herbst 2 days, 11 hours ago
1ba6113a90a0 removed a lot of the kernel GPU channel, but method 0x128
was important as otherwise the GPU spams us with `CACHE_ERROR` messages.

We use the blit subchannel inside our vblank handling, so we should keep
at least this part.

v2: Only do it for NV11+ GPUs

Closes: https://gitlab.freedesktop.org/drm/nouveau/-/issues/201
Fixes: 4a16dd9d18a0 ("drm/nouveau/kms: switch to drm fbdev helpers")
Signed-off-by: Karol Herbst <kherbst@redhat.com>
---
 drivers/gpu/drm/nouveau/nouveau_chan.c |  1 +
 drivers/gpu/drm/nouveau/nouveau_chan.h |  1 +
 drivers/gpu/drm/nouveau/nouveau_drm.c  | 20 +++++++++++++++++---
 3 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_chan.c b/drivers/gpu/drm/nouveau/nouveau_chan.c
index e648ecd0c1a0..3dfbc374478e 100644
--- a/drivers/gpu/drm/nouveau/nouveau_chan.c
+++ b/drivers/gpu/drm/nouveau/nouveau_chan.c
@@ -90,6 +90,7 @@ nouveau_channel_del(struct nouveau_channel **pchan)
 		if (cli)
 			nouveau_svmm_part(chan->vmm->svmm, chan->inst);
 
+		nvif_object_dtor(&chan->blit);
 		nvif_object_dtor(&chan->nvsw);
 		nvif_object_dtor(&chan->gart);
 		nvif_object_dtor(&chan->vram);
diff --git a/drivers/gpu/drm/nouveau/nouveau_chan.h b/drivers/gpu/drm/nouveau/nouveau_chan.h
index e06a8ffed31a..bad7466bd0d5 100644
--- a/drivers/gpu/drm/nouveau/nouveau_chan.h
+++ b/drivers/gpu/drm/nouveau/nouveau_chan.h
@@ -53,6 +53,7 @@ struct nouveau_channel {
 	u32 user_put;
 
 	struct nvif_object user;
+	struct nvif_object blit;
 
 	struct nvif_event kill;
 	atomic_t killed;
diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c b/drivers/gpu/drm/nouveau/nouveau_drm.c
index cc7c5b4a05fd..9512f1c2f871 100644
--- a/drivers/gpu/drm/nouveau/nouveau_drm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_drm.c
@@ -369,15 +369,29 @@ nouveau_accel_gr_init(struct nouveau_drm *drm)
 		ret = nvif_object_ctor(&drm->channel->user, "drmNvsw",
 				       NVDRM_NVSW, nouveau_abi16_swclass(drm),
 				       NULL, 0, &drm->channel->nvsw);
+
+		if (ret == 0 && device->info.chipset >= 0x11) {
+			ret = nvif_object_ctor(&drm->channel->user, "drmBlit",
+					       0x005f, 0x009f,
+					       NULL, 0, &drm->channel->blit);
+		}
+
 		if (ret == 0) {
 			struct nvif_push *push = drm->channel->chan.push;
-			ret = PUSH_WAIT(push, 2);
-			if (ret == 0)
+			ret = PUSH_WAIT(push, 8);
+			if (ret == 0) {
+				if (device->info.chipset >= 0x11) {
+					PUSH_NVSQ(push, NV05F, 0x0000, drm->channel->blit.handle);
+					PUSH_NVSQ(push, NV09F, 0x0120, 0,
+							       0x0124, 1,
+							       0x0128, 2);
+				}
 				PUSH_NVSQ(push, NV_SW, 0x0000, drm->channel->nvsw.handle);
+			}
 		}
 
 		if (ret) {
-			NV_ERROR(drm, "failed to allocate sw class, %d\n", ret);
+			NV_ERROR(drm, "failed to allocate sw or blit class, %d\n", ret);
 			nouveau_accel_gr_fini(drm);
 			return;
 		}
-- 
2.40.1
Re: [Nouveau] [PATCH v2] drm/nouveau: bring back blit subchannel for pre nv50 GPUs
Posted by Ilia Mirkin 2 days, 5 hours ago
On Fri, May 26, 2023 at 5:11 AM Karol Herbst <kherbst@redhat.com> wrote:
>
> 1ba6113a90a0 removed a lot of the kernel GPU channel, but method 0x128
> was important as otherwise the GPU spams us with `CACHE_ERROR` messages.
>
> We use the blit subchannel inside our vblank handling, so we should keep
> at least this part.
>
> v2: Only do it for NV11+ GPUs
>
> Closes: https://gitlab.freedesktop.org/drm/nouveau/-/issues/201
> Fixes: 4a16dd9d18a0 ("drm/nouveau/kms: switch to drm fbdev helpers")
> Signed-off-by: Karol Herbst <kherbst@redhat.com>
> ---
>  drivers/gpu/drm/nouveau/nouveau_chan.c |  1 +
>  drivers/gpu/drm/nouveau/nouveau_chan.h |  1 +
>  drivers/gpu/drm/nouveau/nouveau_drm.c  | 20 +++++++++++++++++---
>  3 files changed, 19 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/nouveau/nouveau_chan.c b/drivers/gpu/drm/nouveau/nouveau_chan.c
> index e648ecd0c1a0..3dfbc374478e 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_chan.c
> +++ b/drivers/gpu/drm/nouveau/nouveau_chan.c
> @@ -90,6 +90,7 @@ nouveau_channel_del(struct nouveau_channel **pchan)
>                 if (cli)
>                         nouveau_svmm_part(chan->vmm->svmm, chan->inst);
>
> +               nvif_object_dtor(&chan->blit);
>                 nvif_object_dtor(&chan->nvsw);
>                 nvif_object_dtor(&chan->gart);
>                 nvif_object_dtor(&chan->vram);
> diff --git a/drivers/gpu/drm/nouveau/nouveau_chan.h b/drivers/gpu/drm/nouveau/nouveau_chan.h
> index e06a8ffed31a..bad7466bd0d5 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_chan.h
> +++ b/drivers/gpu/drm/nouveau/nouveau_chan.h
> @@ -53,6 +53,7 @@ struct nouveau_channel {
>         u32 user_put;
>
>         struct nvif_object user;
> +       struct nvif_object blit;
>
>         struct nvif_event kill;
>         atomic_t killed;
> diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c b/drivers/gpu/drm/nouveau/nouveau_drm.c
> index cc7c5b4a05fd..9512f1c2f871 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_drm.c
> +++ b/drivers/gpu/drm/nouveau/nouveau_drm.c
> @@ -369,15 +369,29 @@ nouveau_accel_gr_init(struct nouveau_drm *drm)
>                 ret = nvif_object_ctor(&drm->channel->user, "drmNvsw",
>                                        NVDRM_NVSW, nouveau_abi16_swclass(drm),
>                                        NULL, 0, &drm->channel->nvsw);
> +
> +               if (ret == 0 && device->info.chipset >= 0x11) {

Can you double-check that this is needed on NV15? IIRC there's some
non-linearity of chipsets here which is why we had (some long time
ago, not sure if it's still there), a chip class which would simplify
such checks.

Cheers,

  -ilia