gpu: nvgpu: disable IRQs before preparing powering down

Disable IRQs and wait for completion before preparing powering
down. This avoids concurrency with threaded interrupts.

JIRA EVLR-1852

Change-Id: Iab4cfb0e796b5748430d38daa2a3be8c03b10fff
Signed-off-by: Thomas Fleury <tfleury@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1563896
GVS: Gerrit_Virtual_Submit
Reviewed-by: Deepak Nibade <dnibade@nvidia.com>
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 18 insertions, 11 deletions

diff --git a/drivers/gpu/nvgpu/common/linux/module.c b/drivers/gpu/nvgpu/common/linux/module.c
index e7e79949..68ae1a66 100644
--- a/drivers/gpu/nvgpu/common/linux/module.c
+++ b/drivers/gpu/nvgpu/common/linux/module.c
@@ -268,6 +268,7 @@ static int gk20a_pm_prepare_poweroff(struct device *dev)
         struct nvgpu_os_linux *l = nvgpu_os_linux_from_gk20a(g);
         int ret = 0;
         struct gk20a_platform *platform = gk20a_get_platform(dev);
+        bool irqs_enabled;
 
         gk20a_dbg_fn("");
 
@@ -276,6 +277,15 @@ static int gk20a_pm_prepare_poweroff(struct device *dev)
         if (!g->power_on)
                 goto done;
 
+        /* disable IRQs and wait for completion */
+        irqs_enabled = g->irqs_enabled;
+        if (irqs_enabled) {
+                disable_irq(g->irq_stall);
+                if (g->irq_stall != g->irq_nonstall)
+                        disable_irq(g->irq_nonstall);
+                g->irqs_enabled = 0;
+        }
+
         gk20a_scale_suspend(dev);
 
         gk20a_cde_suspend(l);
@@ -284,17 +294,6 @@ static int gk20a_pm_prepare_poweroff(struct device *dev)
         if (ret)
                 goto error;
 
-        /*
-         * After this point, gk20a interrupts should not get
-         * serviced.
-         */
-        if (g->irqs_enabled) {
-                disable_irq(g->irq_stall);
-                if (g->irq_stall != g->irq_nonstall)
-                        disable_irq(g->irq_nonstall);
-                g->irqs_enabled = 0;
-        }
-
         /* Decrement platform power refcount */
         if (platform->idle)
                 platform->idle(dev);
@@ -306,6 +305,14 @@ static int gk20a_pm_prepare_poweroff(struct device *dev)
         return 0;
 
 error:
+        /* re-enabled IRQs if previously enabled */
+        if (irqs_enabled) {
+                enable_irq(g->irq_stall);
+                if (g->irq_stall != g->irq_nonstall)
+                        enable_irq(g->irq_nonstall);
+                g->irqs_enabled = 1;
+        }
+
         gk20a_scale_resume(dev);
 done:
         nvgpu_mutex_release(&g->poweroff_lock);