4.19-stable review patch. If anyone has any objections, please let me know.
------------------ From: Ben Skeggs <bske...@redhat.com> commit 970a5ee41c72df46e3b0f307528c7d8ef7734a2e upstream. Should hopefully fix a regression some people have been seeing since EVO push buffers were moved to VRAM by default on Pascal GPUs. Fixes: d00ddd9da ("drm/nouveau/kms/nv50-: allocate push buffers in vidmem on pascal") Signed-off-by: Ben Skeggs <bske...@redhat.com> Cc: <sta...@vger.kernel.org> # 4.19+ Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- drivers/gpu/drm/nouveau/dispnv50/disp.c | 29 ++++++++++++++++++----------- 1 file changed, 18 insertions(+), 11 deletions(-) --- a/drivers/gpu/drm/nouveau/dispnv50/disp.c +++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c @@ -197,6 +197,22 @@ nv50_dmac_create(struct nvif_device *dev /****************************************************************************** * EVO channel helpers *****************************************************************************/ +static void +evo_flush(struct nv50_dmac *dmac) +{ + /* Push buffer fetches are not coherent with BAR1, we need to ensure + * writes have been flushed right through to VRAM before writing PUT. + */ + if (dmac->push.type & NVIF_MEM_VRAM) { + struct nvif_device *device = dmac->base.device; + nvif_wr32(&device->object, 0x070000, 0x00000001); + nvif_msec(device, 2000, + if (!(nvif_rd32(&device->object, 0x070000) & 0x00000002)) + break; + ); + } +} + u32 * evo_wait(struct nv50_dmac *evoc, int nr) { @@ -207,6 +223,7 @@ evo_wait(struct nv50_dmac *evoc, int nr) mutex_lock(&dmac->lock); if (put + nr >= (PAGE_SIZE / 4) - 8) { dmac->ptr[put] = 0x20000000; + evo_flush(dmac); nvif_wr32(&dmac->base.user, 0x0000, 0x00000000); if (nvif_msec(device, 2000, @@ -229,17 +246,7 @@ evo_kick(u32 *push, struct nv50_dmac *ev { struct nv50_dmac *dmac = evoc; - /* Push buffer fetches are not coherent with BAR1, we need to ensure - * writes have been flushed right through to VRAM before writing PUT. - */ - if (dmac->push.type & NVIF_MEM_VRAM) { - struct nvif_device *device = dmac->base.device; - nvif_wr32(&device->object, 0x070000, 0x00000001); - nvif_msec(device, 2000, - if (!(nvif_rd32(&device->object, 0x070000) & 0x00000002)) - break; - ); - } + evo_flush(dmac); nvif_wr32(&dmac->base.user, 0x0000, (push - dmac->ptr) << 2); mutex_unlock(&dmac->lock);