gpu: nvgpu: Move deferred interrupt wait code

Move the code that waits for deferred interrupts to nvgpu_common.c and
make it global. Also rename that function to use nvgpu_ as the function
prefix.

Bug 1816516
Bug 1807277

Change-Id: I42c4982ea853af5489051534219bfe8b253c2784
Signed-off-by: Alex Waterman <alexw@nvidia.com>
Reviewed-on: http://git-master/r/1250027
(cherry picked from commit cb6fb03e20b08e5c3606ae8a5a9c237bfdf9e7da)
Reviewed-on: http://git-master/r/1274475
GVS: Gerrit_Virtual_Submit
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>

1 files changed, 39 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/nvgpu_common.c b/drivers/gpu/nvgpu/nvgpu_common.c
index a1f4832b..a2673b26 100644
--- a/drivers/gpu/nvgpu/nvgpu_common.c
+++ b/drivers/gpu/nvgpu/nvgpu_common.c
@@ -231,3 +231,42 @@ const struct firmware *nvgpu_request_firmware(struct gk20a *g,
 
         return fw;
 }
+
+/**
+ * cyclic_delta - Returns delta of cyclic integers a and b.
+ *
+ * @a - First integer
+ * @b - Second integer
+ *
+ * Note: if a is ahead of b, delta is positive.
+ */
+static int cyclic_delta(int a, int b)
+{
+        return a - b;
+}
+
+/**
+ * nvgpu_wait_for_deferred_interrupts - Wait for interrupts to complete
+ *
+ * @g - The GPU to wait on.
+ *
+ * Waits until all interrupt handlers that have been scheduled to run have
+ * completed.
+ */
+void nvgpu_wait_for_deferred_interrupts(struct gk20a *g)
+{
+        int stall_irq_threshold = atomic_read(&g->hw_irq_stall_count);
+        int nonstall_irq_threshold = atomic_read(&g->hw_irq_nonstall_count);
+
+        /* wait until all stalling irqs are handled */
+        wait_event(g->sw_irq_stall_last_handled_wq,
+                   cyclic_delta(stall_irq_threshold,
+                                atomic_read(&g->sw_irq_stall_last_handled))
+                   <= 0);
+
+        /* wait until all non-stalling irqs are handled */
+        wait_event(g->sw_irq_nonstall_last_handled_wq,
+                   cyclic_delta(nonstall_irq_threshold,
+                                atomic_read(&g->sw_irq_nonstall_last_handled))
+                   <= 0);
+}