[PATCH AUTOSEL for 4.9 12/52] drm/nouveau/pci: do a msi rearm on init

Sasha Levin
2018-02-03T18:29:31Z

From: Karol Herbst <kherbst@redhat.com>

[ Upstream commit a121027d2747168df0aac0c3da35509eea39f61c ]

On my GP107 when I load nouveau after unloading it, for some reason the
GPU stopped sending or the CPU stopped receiving interrupts if MSI was
enabled.

Doing a rearm once before getting any interrupts fixes this.

Signed-off-by: Karol Herbst <kherbst@redhat.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
---
drivers/gpu/drm/nouveau/nvkm/subdev/pci/base.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/base.c b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/base.c
index a4cb82495cee..245c946ea661 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/base.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/base.c
@@ -136,6 +136,13 @@ nvkm_pci_init(struct nvkm_subdev *subdev)
return ret;

pci->irq = pdev->irq;
+
+ /* Ensure MSI interrupts are armed, for the case where there are
+ * already interrupts pending (for whatever reason) at load time.
+ */
+ if (pci->msi)
+ pci->func->msi_rearm(pci);
+
return ret;
}

--
2.11.0