Previously, it looked as if we were able to fix suspend/resume on some
desktops by setting Gcoff based on whether or not we were entering runtime
PM. This was a mistake though - the only time suspend/resume would end up
actually working was if Gcoff = 0.

It seems like it's likely the main reason for this is the FBSR GcOff
argument actually controls GSP's behavior with regards to which buffers it
decides to save across suspend/resume. When GcOff = 1, RM reserved regions
are saved unless they are marked as LOST_ON_SUSPEND, and RM channel-context
and kernel-client buffers are also saved -including- when they are
LOST_ON_SUSPEND. This means with GcOff = 1, we end up having GSP save and
restore buffers that actually need to be reinitialized on resume - causing
the failures we're setting.

Thanks to John Hubbard from Nvidia for providing some background on what
these options do in the GSP firmware do!

Signed-off-by: Lyude Paul <[email protected]>
Fixes: 53dac0623853 ("drm/nouveau/gsp: add support for 570.144")
Cc: <[email protected]> # v6.16+

---
V5:
* Fix commit title, GcOff should be 0 not 1

 drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r570/fbsr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r570/fbsr.c 
b/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r570/fbsr.c
index 2945d5b4e5707..af5aa5065c3dd 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r570/fbsr.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r570/fbsr.c
@@ -81,7 +81,7 @@ r570_fbsr_init(struct nvkm_gsp *gsp, struct sg_table *sgt, 
u64 size)
        ctrl->hClient = gsp->internal.client.object.handle;
        ctrl->hSysMem = memlist.handle;
        ctrl->sysmemAddrOfSuspendResumeData = gsp->sr.meta.addr;
-       ctrl->bEnteringGcoffState = 1;
+       ctrl->bEnteringGcoffState = 0;
 
        ret = nvkm_gsp_rm_ctrl_wr(&gsp->internal.device.subdevice, ctrl);
        if (ret)
-- 
2.55.0

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