Nouveau - Aug 2023 - Patch "drm/nouveau/gr: enable memory loads on helper invocation on all channels" has been added to the 4.19-stable tree

This is a note to let you know that I've just added the patch titled

    drm/nouveau/gr: enable memory loads on helper invocation on all channels

to the 4.19-stable tree which can be found at:
   
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
    
drm-nouveau-gr-enable-memory-loads-on-helper-invocation-on-all-channels.patch
and it can be found in the queue-4.19 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable at vger.kernel.org> know about it.

>From 1cb9e2ef66d53b020842b18762e30d0eb4384de8 Mon Sep 17 00:00:00 2001
From: Karol Herbst <kherbst at redhat.com>
Date: Thu, 22 Jun 2023 17:20:17 +0200
Subject: drm/nouveau/gr: enable memory loads on helper invocation on all
channels

From: Karol Herbst <kherbst at redhat.com>

commit 1cb9e2ef66d53b020842b18762e30d0eb4384de8 upstream.

We have a lurking bug where Fragment Shader Helper Invocations can't load
from memory. But this is actually required in OpenGL and is causing random
hangs or failures in random shaders.

It is unknown how widespread this issue is, but shaders hitting this can
end up with infinite loops.

We enable those only on all Kepler and newer GPUs where we use our own
Firmware.

Nvidia's firmware provides a way to set a kernelspace controlled list of
mmio registers in the gr space from push buffers via MME macros.

v2: drop code for gm200 and newer.

Cc: Ben Skeggs <bskeggs at redhat.com>
Cc: David Airlie <airlied at gmail.com>
Cc: nouveau at lists.freedesktop.org
Cc: stable at vger.kernel.org # 4.19+
Signed-off-by: Karol Herbst <kherbst at redhat.com>
Reviewed-by: Dave Airlie <airlied at redhat.com>
Link:
https://patchwork.freedesktop.org/patch/msgid/20230622152017.2512101-1-kherbst
at redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
---
 drivers/gpu/drm/nouveau/nvkm/engine/gr/ctxgf100.h  |    1 +
 drivers/gpu/drm/nouveau/nvkm/engine/gr/ctxgk104.c  |    4 +++-
 drivers/gpu/drm/nouveau/nvkm/engine/gr/ctxgk110.c  |   10 ++++++++++
 drivers/gpu/drm/nouveau/nvkm/engine/gr/ctxgk110b.c |    1 +
 drivers/gpu/drm/nouveau/nvkm/engine/gr/ctxgk208.c  |    1 +
 drivers/gpu/drm/nouveau/nvkm/engine/gr/ctxgm107.c  |    1 +
 6 files changed, 17 insertions(+), 1 deletion(-)

--- a/drivers/gpu/drm/nouveau/nvkm/engine/gr/ctxgf100.h
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/gr/ctxgf100.h
@@ -121,6 +121,7 @@ void gk104_grctx_generate_r418800(struct
 
 extern const struct gf100_grctx_func gk110_grctx;
 void gk110_grctx_generate_r419eb0(struct gf100_gr *);
+void gk110_grctx_generate_r419f78(struct gf100_gr *);
 
 extern const struct gf100_grctx_func gk110b_grctx;
 extern const struct gf100_grctx_func gk208_grctx;
--- a/drivers/gpu/drm/nouveau/nvkm/engine/gr/ctxgk104.c
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/gr/ctxgk104.c
@@ -916,7 +916,9 @@ static void
 gk104_grctx_generate_r419f78(struct gf100_gr *gr)
 {
 	struct nvkm_device *device = gr->base.engine.subdev.device;
-	nvkm_mask(device, 0x419f78, 0x00000001, 0x00000000);
+
+	/* bit 3 set disables loads in fp helper invocations, we need it enabled */
+	nvkm_mask(device, 0x419f78, 0x00000009, 0x00000000);
 }
 
 void
--- a/drivers/gpu/drm/nouveau/nvkm/engine/gr/ctxgk110.c
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/gr/ctxgk110.c
@@ -820,6 +820,15 @@ gk110_grctx_generate_r419eb0(struct gf10
 	nvkm_mask(device, 0x419eb0, 0x00001000, 0x00001000);
 }
 
+void
+gk110_grctx_generate_r419f78(struct gf100_gr *gr)
+{
+	struct nvkm_device *device = gr->base.engine.subdev.device;
+
+	/* bit 3 set disables loads in fp helper invocations, we need it enabled */
+	nvkm_mask(device, 0x419f78, 0x00000008, 0x00000000);
+}
+
 const struct gf100_grctx_func
 gk110_grctx = {
 	.main  = gf100_grctx_generate_main,
@@ -852,4 +861,5 @@ gk110_grctx = {
 	.gpc_tpc_nr = gk104_grctx_generate_gpc_tpc_nr,
 	.r418800 = gk104_grctx_generate_r418800,
 	.r419eb0 = gk110_grctx_generate_r419eb0,
+	.r419f78 = gk110_grctx_generate_r419f78,
 };
--- a/drivers/gpu/drm/nouveau/nvkm/engine/gr/ctxgk110b.c
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/gr/ctxgk110b.c
@@ -101,4 +101,5 @@ gk110b_grctx = {
 	.gpc_tpc_nr = gk104_grctx_generate_gpc_tpc_nr,
 	.r418800 = gk104_grctx_generate_r418800,
 	.r419eb0 = gk110_grctx_generate_r419eb0,
+	.r419f78 = gk110_grctx_generate_r419f78,
 };
--- a/drivers/gpu/drm/nouveau/nvkm/engine/gr/ctxgk208.c
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/gr/ctxgk208.c
@@ -566,4 +566,5 @@ gk208_grctx = {
 	.dist_skip_table = gf117_grctx_generate_dist_skip_table,
 	.gpc_tpc_nr = gk104_grctx_generate_gpc_tpc_nr,
 	.r418800 = gk104_grctx_generate_r418800,
+	.r419f78 = gk110_grctx_generate_r419f78,
 };
--- a/drivers/gpu/drm/nouveau/nvkm/engine/gr/ctxgm107.c
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/gr/ctxgm107.c
@@ -991,4 +991,5 @@ gm107_grctx = {
 	.r406500 = gm107_grctx_generate_r406500,
 	.gpc_tpc_nr = gk104_grctx_generate_gpc_tpc_nr,
 	.r419e00 = gm107_grctx_generate_r419e00,
+	.r419f78 = gk110_grctx_generate_r419f78,
 };


Patches currently in stable-queue which might be from kherbst at redhat.com are

queue-4.19/drm-nouveau-gr-enable-memory-loads-on-helper-invocation-on-all-channels.patch