gpu: nvgpu: Deal with invalid MMU id

If gk20a_engine_id_to_mmu_id() fails, it returns ~0. Deal with this
by checking the results in each call to it.

Change-Id: I6fb9f7151f21a6c4694bfb2ea3c960d344fe629f
Signed-off-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-on: http://git-master/r/1249965
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

2 files changed, 19 insertions, 13 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/fifo_gk20a.c b/drivers/gpu/nvgpu/gk20a/fifo_gk20a.c
index b4850ee3..9887b68f 100644
--- a/drivers/gpu/nvgpu/gk20a/fifo_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/fifo_gk20a.c
@@ -1557,15 +1557,18 @@ static void gk20a_fifo_trigger_mmu_fault(struct gk20a *g,
 
         /* trigger faults for all bad engines */
         for_each_set_bit(engine_id, &engine_ids, 32) {
+                u32 mmu_id;
+
                 if (!gk20a_fifo_is_valid_engine_id(g, engine_id)) {
                         WARN_ON(true);
                         break;
                 }
 
-                gk20a_writel(g, fifo_trigger_mmu_fault_r(engine_id),
-                             fifo_trigger_mmu_fault_id_f(
-                             gk20a_engine_id_to_mmu_id(g, engine_id)) |
-                             fifo_trigger_mmu_fault_enable_f(1));
+                mmu_id = gk20a_engine_id_to_mmu_id(g, engine_id);
+                if (mmu_id != ~0)
+                        gk20a_writel(g, fifo_trigger_mmu_fault_r(engine_id),
+                                     fifo_trigger_mmu_fault_id_f(mmu_id) |
+                                     fifo_trigger_mmu_fault_enable_f(1));
         }
 
         /* Wait for MMU fault to trigger */
@@ -1707,8 +1710,10 @@ void gk20a_fifo_recover(struct gk20a *g, u32 __engine_ids,
                 /* atleast one engine will get passed during sched err*/
                 engine_ids |= __engine_ids;
                 for_each_set_bit(engine_id, &engine_ids, 32) {
-                        mmu_fault_engines |=
-                                BIT(gk20a_engine_id_to_mmu_id(g, engine_id));
+                        u32 mmu_id = gk20a_engine_id_to_mmu_id(g, engine_id);
+
+                        if (mmu_id != ~0)
+                                mmu_fault_engines |= BIT(mmu_id);
                 }
         } else {
                 /* store faulted engines in advance */
@@ -1728,9 +1733,11 @@ void gk20a_fifo_recover(struct gk20a *g, u32 __engine_ids,
 
                                 gk20a_fifo_get_faulty_id_type(g, active_engine_id, &id, &type);
                                 if (ref_type == type && ref_id == id) {
+                                        u32 mmu_id = gk20a_engine_id_to_mmu_id(g, active_engine_id);
+
                                         engine_ids |= BIT(active_engine_id);
-                                        mmu_fault_engines |=
-                                        BIT(gk20a_engine_id_to_mmu_id(g, active_engine_id));
+                                        if (mmu_id != ~0)
+                                                mmu_fault_engines |= BIT(mmu_id);
                                 }
                         }
                 }
diff --git a/drivers/gpu/nvgpu/gm20b/fifo_gm20b.c b/drivers/gpu/nvgpu/gm20b/fifo_gm20b.c
index a8934035..3b877db1 100644
--- a/drivers/gpu/nvgpu/gm20b/fifo_gm20b.c
+++ b/drivers/gpu/nvgpu/gm20b/fifo_gm20b.c
@@ -74,16 +74,15 @@ static void gm20b_fifo_trigger_mmu_fault(struct gk20a *g,
 
         /* trigger faults for all bad engines */
         for_each_set_bit(engine_id, &engine_ids, 32) {
-                u32 engine_mmu_fault_id;
-
                 if (!gk20a_fifo_is_valid_engine_id(g, engine_id)) {
                         gk20a_err(dev_from_gk20a(g),
                                   "faulting unknown engine %ld", engine_id);
                 } else {
-                        engine_mmu_fault_id = gm20b_engine_id_to_mmu_id(g,
+                        u32 mmu_id = gm20b_engine_id_to_mmu_id(g,
                                                                 engine_id);
-                        gk20a_writel(g, fifo_trigger_mmu_fault_r(engine_id),
-                                     fifo_trigger_mmu_fault_enable_f(1));
+                        if (mmu_id != ~0)
+                                gk20a_writel(g, fifo_trigger_mmu_fault_r(mmu_id),
+                                             fifo_trigger_mmu_fault_enable_f(1));
                 }
         }