gpu: nvgpu: add flag for CAR reset in do_idle()

Add "force_reset" flag to __gk20a_do_idle()

For real world use cases like VPR resizing, we cannot wait
for railgate_delay (which is 500 mS). Hence use CAR reset
for this use case. (this is done via gk20a_do_idle() API
with force_reset = true)

Some of the test cases make use of sysfs "force_idle" and
they expect GPU to be into really railgated state and
not in CAR reset.
Hence when called from sysfs, set force_reset = false.

When global flag "force_reset_in_do_idle" is set, it will
override local flags and force CAR reset case.
This is desired in cases where railgating is not enabled

Also, set force_reset_in_do_idle = false for GM20B since
railgating has been enabled for GM20B

Bug 1592997

Change-Id: I6c5af2977c7211ef82551a86a7c1eb51b8ccee60
Signed-off-by: Deepak Nibade <dnibade@nvidia.com>
Reviewed-on: http://git-master/r/711615
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Tested-by: Terje Bergstrom <tbergstrom@nvidia.com>

4 files changed, 11 insertions, 8 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/gk20a.c b/drivers/gpu/nvgpu/gk20a/gk20a.c
index 76237fae..b7357c6b 100644
--- a/drivers/gpu/nvgpu/gk20a/gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/gk20a.c
@@ -1629,7 +1629,7 @@ void gk20a_reset(struct gk20a *g, u32 units)
  *
  * In success, this call MUST be balanced by caller with __gk20a_do_unidle()
  */
-int __gk20a_do_idle(struct platform_device *pdev)
+int __gk20a_do_idle(struct platform_device *pdev, bool force_reset)
 {
         struct gk20a *g = get_gk20a(pdev);
         struct gk20a_platform *platform = dev_get_drvdata(&pdev->dev);
@@ -1648,6 +1648,9 @@ int __gk20a_do_idle(struct platform_device *pdev)
         if (platform->is_railgated(pdev))
                 return 0;
 
+        /* check if global force_reset flag is set */
+        force_reset |= platform->force_reset_in_do_idle;
+
         /* prevent suspend by incrementing usage counter */
         pm_runtime_get_noresume(&pdev->dev);
 
@@ -1674,7 +1677,7 @@ int __gk20a_do_idle(struct platform_device *pdev)
          */
         pm_runtime_put_sync(&pdev->dev);
 
-        if (platform->can_railgate && !platform->force_reset_in_do_idle) {
+        if (platform->can_railgate && !force_reset) {
                 /* add sufficient delay to allow GPU to rail gate */
                 msleep(platform->railgate_delay);
 
@@ -1727,7 +1730,7 @@ int gk20a_do_idle(void)
                         of_find_matching_node(NULL, tegra_gk20a_of_match);
         struct platform_device *pdev = of_find_device_by_node(node);
 
-        int ret =  __gk20a_do_idle(pdev);
+        int ret =  __gk20a_do_idle(pdev, true);
 
         of_node_put(node);
 
diff --git a/drivers/gpu/nvgpu/gk20a/gk20a.h b/drivers/gpu/nvgpu/gk20a/gk20a.h
index ba7c7e97..acee2e48 100644
--- a/drivers/gpu/nvgpu/gk20a/gk20a.h
+++ b/drivers/gpu/nvgpu/gk20a/gk20a.h
@@ -776,7 +776,7 @@ void gk20a_idle(struct platform_device *pdev);
 void gk20a_disable(struct gk20a *g, u32 units);
 void gk20a_enable(struct gk20a *g, u32 units);
 void gk20a_reset(struct gk20a *g, u32 units);
-int __gk20a_do_idle(struct platform_device *pdev);
+int __gk20a_do_idle(struct platform_device *pdev, bool force_reset);
 int __gk20a_do_unidle(struct platform_device *pdev);
 
 const struct firmware *
diff --git a/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c b/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c
index 7baadf2e..a70ce4b2 100644
--- a/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c
+++ b/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c
@@ -3,7 +3,7 @@
  *
  * GK20A Graphics
  *
- * Copyright (c) 2011-2014, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2011-2015, NVIDIA CORPORATION.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -562,7 +562,7 @@ static ssize_t force_idle_store(struct device *device,
                 if (g->forced_idle)
                         return count; /* do nothing */
                 else {
-                        err = __gk20a_do_idle(ndev);
+                        err = __gk20a_do_idle(ndev, false);
                         if (!err) {
                                 g->forced_idle = 1;
                                 dev_info(device, "gpu is idle : %d\n",
diff --git a/drivers/gpu/nvgpu/gk20a/platform_gk20a_tegra.c b/drivers/gpu/nvgpu/gk20a/platform_gk20a_tegra.c
index 28b7ff7b..0d5f32dd 100644
--- a/drivers/gpu/nvgpu/gk20a/platform_gk20a_tegra.c
+++ b/drivers/gpu/nvgpu/gk20a/platform_gk20a_tegra.c
@@ -3,7 +3,7 @@
  *
  * GK20A Tegra Platform Interface
  *
- * Copyright (c) 2014, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2014-2015, NVIDIA CORPORATION.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -597,7 +597,7 @@ struct gk20a_platform gm20b_tegra_platform = {
         .enable_elpg            = true,
         .enable_aelpg           = true,
 
-        .force_reset_in_do_idle = true,
+        .force_reset_in_do_idle = false,
 
         .default_big_page_size  = SZ_128K,