gpu: nvgpu: gv11b: fix fb flush issue

membar.sys does synchronization with the whole system (GPU and CPU),
membar.gl does synchronization within the GPU.
In gv11b, fb flush is generating membar.gl instead of membar.sys, which
is an issue. To fix this issue. following WAR is used:
1. Use bar1 engine id and bind it to a particular pdb,
2. Then instead of a fb_flush, issue a tlb invalidate of the bar1 pdb.

Now allocation of vm for bar1 instance block and bar1 binding is done
without check for bar1 support. Only bar1 register mapping is done
based on bar1 support enabled.

Bug 2112790

Change-Id: I76f43f1178a68f10823d48bc9da55d2bd686dd52
Signed-off-by: seshendra Gadagottu <sgadagottu@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1750257
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 5 insertions, 1 deletions

diff --git a/drivers/gpu/nvgpu/gv11b/mm_gv11b.c b/drivers/gpu/nvgpu/gv11b/mm_gv11b.c
index e1d90829..0cf08d4a 100644
--- a/drivers/gpu/nvgpu/gv11b/mm_gv11b.c
+++ b/drivers/gpu/nvgpu/gv11b/mm_gv11b.c
@@ -249,7 +249,11 @@ void gv11b_mm_l2_flush(struct gk20a *g, bool invalidate)
 
         g->ops.mm.fb_flush(g);
         gk20a_mm_l2_flush(g, invalidate);
-        g->ops.mm.fb_flush(g);
+        if (g->ops.bus.bar1_bind)
+                g->ops.fb.tlb_invalidate(g,
+                                g->mm.bar1.vm->pdb.mem);
+        else
+                g->ops.mm.fb_flush(g);
 }
 
 /*