gpu: nvgpu: refactor interrupt handling

JIRA: EVLR-1004

(*) Refactor the non-stalling interrupt path to execute clear on the
top half, so on dGPU case processing of stalling interrupts does not
block non-stalling one.
(*) Use a worker thread to do semaphore wakeups and allow batching of
the non-stalling operations.
(*) Fix a bug where some gpus will not properly track the completion
of interrupts, preventing safe driver unloads

Change-Id: Icc90a3acba544c97ec6a9285ab235d337ab9eefa
Signed-off-by: David Nieto <dmartineznie@nvidia.com>
Reviewed-on: http://git-master/r/1312796
Reviewed-by: svccoveritychecker <svccoveritychecker@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Lakshmanan M <lm@nvidia.com>
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-by: Navneet Kumar <navneetk@nvidia.com>

1 files changed, 5 insertions, 6 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/ce2_gk20a.c b/drivers/gpu/nvgpu/gk20a/ce2_gk20a.c
index db1ac539..3fed937e 100644
--- a/drivers/gpu/nvgpu/gk20a/ce2_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/ce2_gk20a.c
@@ -76,8 +76,9 @@ void gk20a_ce2_isr(struct gk20a *g, u32 inst_id, u32 pri_base)
         return;
 }
 
-void gk20a_ce2_nonstall_isr(struct gk20a *g, u32 inst_id, u32 pri_base)
+int gk20a_ce2_nonstall_isr(struct gk20a *g, u32 inst_id, u32 pri_base)
 {
+        int ops = 0;
         u32 ce2_intr = gk20a_readl(g, ce2_intr_status_r());
 
         gk20a_dbg(gpu_dbg_intr, "ce2 nonstall isr %08x\n", ce2_intr);
@@ -85,12 +86,10 @@ void gk20a_ce2_nonstall_isr(struct gk20a *g, u32 inst_id, u32 pri_base)
         if (ce2_intr & ce2_intr_status_nonblockpipe_pending_f()) {
                 gk20a_writel(g, ce2_intr_status_r(),
                         ce2_nonblockpipe_isr(g, ce2_intr));
-
-                /* wake threads waiting in this channel */
-                gk20a_channel_semaphore_wakeup(g, true);
+                ops |= (gk20a_nonstall_ops_wakeup_semaphore |
+                        gk20a_nonstall_ops_post_events);
         }
-
-        return;
+        return ops;
 }
 void gk20a_init_ce2(struct gpu_ops *gops)
 {