drm/nouveau/bar/gk20a: Avoid bar teardown during init

Commit bbb163e18960 ("drm/nouveau/bar: implement bar1 teardown")
introduced add a teardown helper function for BAR1. During
initialisation of the Nouveau, initially all the teardown helpers are
called once, before calling their init counterparts. For gk20a, after
the BAR1 teardown function is called, the device is hanging during the
initialisation of the FB sub-device. At this point it is unclear why
this is happening and this is still under investigation. However, this
change is preventing Tegra124 devices from booting when Nouveau is
enabled. To allow Tegra124 to boot, remove the teardown helper for
gk20a.

This is based upon a previous patch by Guillaume Tucker but limits
the workaround to only gk20a GPUs.

Fixes: bbb163e18960 ("drm/nouveau/bar: implement bar1 teardown")
Reported-by: Guillaume Tucker <guillaume.tucker@collabora.com>
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/bar/base.c b/drivers/gpu/drm/nouveau/nvkm/subdev/bar/base.c
index 9646adec57cbc169cff79363a8d1e4be6ec4accf..243f0a5c8a62530007c7815d226d46b3fb7f0fbd 100644 (file)
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/bar/base.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/bar/base.c
@@ -73,7 +73,8 @@ static int
 nvkm_bar_fini(struct nvkm_subdev *subdev, bool suspend)
 {
        struct nvkm_bar *bar = nvkm_bar(subdev);
-       bar->func->bar1.fini(bar);
+       if (bar->func->bar1.fini)
+               bar->func->bar1.fini(bar);
        return 0;
 }
 

diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/bar/gk20a.c b/drivers/gpu/drm/nouveau/nvkm/subdev/bar/gk20a.c
index b10077d38839b6ce314edfa64bb9692c2a3ba61c..35878fb538f2c58fb1116c367c2314b3a391e7bd 100644 (file)
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/bar/gk20a.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/bar/gk20a.c
@@ -26,7 +26,6 @@ gk20a_bar_func = {
        .dtor = gf100_bar_dtor,
        .oneinit = gf100_bar_oneinit,
        .bar1.init = gf100_bar_bar1_init,
-       .bar1.fini = gf100_bar_bar1_fini,
        .bar1.wait = gf100_bar_bar1_wait,
        .bar1.vmm = gf100_bar_bar1_vmm,
        .flush = g84_bar_flush,