gpu: nvgpu: Reset priv ring properly on error

We did not follow the proper sequence to reset priv ring on error.
Instead we just re-enabled priv ring, which does not reset anything.

Rename the gk20a_reset_priv_ring() to gk20a_enable_priv_ring() to
indicate its proper use. Add another gk20a_reset_priv_ring() which
actually resets priv ring properly.

Change-Id: Ied74465b1215daa447a565b7e9cafef7fbe67d1b
Signed-off-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-on: http://git-master/r/1294681
Reviewed-by: Seema Khowala <seemaj@nvidia.com>
Reviewed-by: svccoveritychecker <svccoveritychecker@nvidia.com>
GVS: Gerrit_Virtual_Submit

3 files changed, 26 insertions, 7 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/gk20a.c b/drivers/gpu/nvgpu/gk20a/gk20a.c
index 16acc1c9..a2fb8dc8 100644
--- a/drivers/gpu/nvgpu/gk20a/gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/gk20a.c
@@ -933,7 +933,7 @@ int gk20a_pm_finalize_poweron(struct device *dev)
         if (g->ops.clk.disable_slowboot)
                 g->ops.clk.disable_slowboot(g);
 
-        gk20a_reset_priv_ring(g);
+        gk20a_enable_priv_ring(g);
 
         /* TBD: move this after graphics init in which blcg/slcg is enabled.
            This function removes SlowdownOnBoot which applies 32x divider
diff --git a/drivers/gpu/nvgpu/gk20a/priv_ring_gk20a.c b/drivers/gpu/nvgpu/gk20a/priv_ring_gk20a.c
index d16c5fd1..420b65f1 100644
--- a/drivers/gpu/nvgpu/gk20a/priv_ring_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/priv_ring_gk20a.c
@@ -1,7 +1,7 @@
 /*
  * GK20A priv ring
  *
- * Copyright (c) 2011-2016, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2011-2017, 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,
@@ -24,7 +24,7 @@
 #include <nvgpu/hw/gk20a/hw_pri_ringmaster_gk20a.h>
 #include <nvgpu/hw/gk20a/hw_pri_ringstation_sys_gk20a.h>
 
-void gk20a_reset_priv_ring(struct gk20a *g)
+void gk20a_enable_priv_ring(struct gk20a *g)
 {
         struct gk20a_platform *platform = dev_get_drvdata(g->dev);
 
@@ -45,6 +45,27 @@ void gk20a_reset_priv_ring(struct gk20a *g)
 
 }
 
+static void gk20a_reset_priv_ring(struct gk20a *g)
+{
+        u32 val;
+
+        gk20a_reset(g, mc_enable_priv_ring_enabled_f());
+
+        val = gk20a_readl(g, pri_ringstation_sys_decode_config_r());
+        val = set_field(val,
+                        pri_ringstation_sys_decode_config_ring_m(),
+                        pri_ringstation_sys_decode_config_ring_drop_on_ring_not_started_f());
+        gk20a_writel(g, pri_ringstation_sys_decode_config_r(), val);
+
+        gk20a_writel(g, pri_ringmaster_global_ctl_r(),
+                        pri_ringmaster_global_ctl_ring_reset_asserted_f());
+        udelay(20);
+        gk20a_writel(g, pri_ringmaster_global_ctl_r(),
+                        pri_ringmaster_global_ctl_ring_reset_deasserted_f());
+
+        gk20a_enable_priv_ring(g);
+}
+
 void gk20a_priv_ring_isr(struct gk20a *g)
 {
         u32 status0, status1;
diff --git a/drivers/gpu/nvgpu/gk20a/priv_ring_gk20a.h b/drivers/gpu/nvgpu/gk20a/priv_ring_gk20a.h
index cb9d49c7..8a6320d7 100644
--- a/drivers/gpu/nvgpu/gk20a/priv_ring_gk20a.h
+++ b/drivers/gpu/nvgpu/gk20a/priv_ring_gk20a.h
@@ -1,9 +1,7 @@
 /*
- * drivers/video/tegra/host/gk20a/priv_ring_gk20a.h
- *
  * GK20A PRIV ringmaster
  *
- * Copyright (c) 2011-2012, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2011-2017, 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,
@@ -21,7 +19,7 @@
 #ifndef __PRIV_RING_GK20A_H__
 #define __PRIV_RING_GK20A_H__
 
-void gk20a_reset_priv_ring(struct gk20a *g);
+void gk20a_enable_priv_ring(struct gk20a *g);
 void gk20a_priv_ring_isr(struct gk20a *g);
 
 #endif /*__PRIV_RING_GK20A_H__*/