gpu: nvgpu: Add sysfs nodes for timeslice min/max

The timeslice values that can be selected for a particular channel/tsg
are bounded by a static min/max. This change introduces two sysfs
nodes that allow these bounds to be configured from userspace.

min_timeslice_us
max_timeslice_us

Bug 200251974
Bug 1854791

Change-Id: I5d5a14225eee4090e418c7e43629324114f60768
Signed-off-by: Peter Boonstoppel <pboonstoppel@nvidia.com>
Reviewed-on: http://git-master/r/1280372
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

5 files changed, 75 insertions, 13 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/channel_gk20a.c b/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
index 40d6d91c..6cbbdeb0 100644
--- a/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
@@ -44,9 +44,6 @@
 
 #define NVMAP_HANDLE_PARAM_SIZE 1
 
-#define NVGPU_CHANNEL_MIN_TIMESLICE_US 1000
-#define NVGPU_CHANNEL_MAX_TIMESLICE_US 50000
-
 /*
  * Although channels do have pointers back to the gk20a struct that they were
  * created under in cases where the driver is killed that pointer can be bad.
@@ -3345,14 +3342,16 @@ int gk20a_channel_set_priority(struct channel_gk20a *ch, u32 priority)
 
 int gk20a_channel_set_timeslice(struct channel_gk20a *ch, u32 timeslice)
 {
+        struct gk20a *g = ch->g;
+
         if (gk20a_is_channel_marked_as_tsg(ch)) {
                 gk20a_err(dev_from_gk20a(ch->g),
                         "invalid operation for TSG!\n");
                 return -EINVAL;
         }
 
-        if (timeslice < NVGPU_CHANNEL_MIN_TIMESLICE_US ||
-                timeslice > NVGPU_CHANNEL_MAX_TIMESLICE_US)
+        if (timeslice < g->min_timeslice_us ||
+                timeslice > g->max_timeslice_us)
                 return -EINVAL;
 
         ch->timeslice_us = timeslice;
diff --git a/drivers/gpu/nvgpu/gk20a/gk20a.h b/drivers/gpu/nvgpu/gk20a/gk20a.h
index cf147ae8..ff8ffc4f 100644
--- a/drivers/gpu/nvgpu/gk20a/gk20a.h
+++ b/drivers/gpu/nvgpu/gk20a/gk20a.h
@@ -840,6 +840,8 @@ struct gk20a {
         u32 timeslice_low_priority_us;
         u32 timeslice_medium_priority_us;
         u32 timeslice_high_priority_us;
+        u32 min_timeslice_us;
+        u32 max_timeslice_us;
 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,4,0)
         u32 runlist_interleave;
 #else
diff --git a/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c b/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c
index a2980354..307fb681 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) 2011-2016, 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,
@@ -756,6 +756,63 @@ static ssize_t tpc_fs_mask_read(struct device *dev,
 
 static DEVICE_ATTR(tpc_fs_mask, ROOTRW, tpc_fs_mask_read, tpc_fs_mask_store);
 
+static ssize_t min_timeslice_us_read(struct device *dev,
+        struct device_attribute *attr, char *buf)
+{
+        struct gk20a *g = get_gk20a(dev);
+
+        return snprintf(buf, PAGE_SIZE, "%u\n", g->min_timeslice_us);
+}
+
+static ssize_t min_timeslice_us_store(struct device *dev,
+        struct device_attribute *attr, const char *buf, size_t count)
+{
+        struct gk20a *g = get_gk20a(dev);
+        unsigned long val;
+
+        if (kstrtoul(buf, 10, &val) < 0)
+                return -EINVAL;
+
+        if (val > g->max_timeslice_us)
+                return -EINVAL;
+
+        g->min_timeslice_us = val;
+
+        return count;
+}
+
+static DEVICE_ATTR(min_timeslice_us, ROOTRW, min_timeslice_us_read,
+                   min_timeslice_us_store);
+
+static ssize_t max_timeslice_us_read(struct device *dev,
+        struct device_attribute *attr, char *buf)
+{
+        struct gk20a *g = get_gk20a(dev);
+
+        return snprintf(buf, PAGE_SIZE, "%u\n", g->max_timeslice_us);
+}
+
+static ssize_t max_timeslice_us_store(struct device *dev,
+        struct device_attribute *attr, const char *buf, size_t count)
+{
+        struct gk20a *g = get_gk20a(dev);
+        unsigned long val;
+
+        if (kstrtoul(buf, 10, &val) < 0)
+                return -EINVAL;
+
+        if (val < g->min_timeslice_us)
+                return -EINVAL;
+
+        g->max_timeslice_us = val;
+
+        return count;
+}
+
+static DEVICE_ATTR(max_timeslice_us, ROOTRW, max_timeslice_us_read,
+                   max_timeslice_us_store);
+
+
 void gk20a_remove_sysfs(struct device *dev)
 {
         struct gk20a *g = get_gk20a(dev);
@@ -782,6 +839,8 @@ void gk20a_remove_sysfs(struct device *dev)
         device_remove_file(dev, &dev_attr_aelpg_enable);
         device_remove_file(dev, &dev_attr_allow_all);
         device_remove_file(dev, &dev_attr_tpc_fs_mask);
+        device_remove_file(dev, &dev_attr_min_timeslice_us);
+        device_remove_file(dev, &dev_attr_max_timeslice_us);
 
         if (g->host1x_dev && (dev->parent != &g->host1x_dev->dev)) {
                 sysfs_remove_link(&g->host1x_dev->dev.kobj, dev_name(dev));
@@ -822,6 +881,8 @@ void gk20a_create_sysfs(struct device *dev)
         error |= device_create_file(dev, &dev_attr_aelpg_enable);
         error |= device_create_file(dev, &dev_attr_allow_all);
         error |= device_create_file(dev, &dev_attr_tpc_fs_mask);
+        error |= device_create_file(dev, &dev_attr_min_timeslice_us);
+        error |= device_create_file(dev, &dev_attr_max_timeslice_us);
 
         if (g->host1x_dev && (dev->parent != &g->host1x_dev->dev)) {
                 error |= sysfs_create_link(&g->host1x_dev->dev.kobj,
diff --git a/drivers/gpu/nvgpu/gk20a/tsg_gk20a.c b/drivers/gpu/nvgpu/gk20a/tsg_gk20a.c
index 3b2cca0d..81a4b78e 100644
--- a/drivers/gpu/nvgpu/gk20a/tsg_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/tsg_gk20a.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014-2016, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2014-2017, 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,
@@ -26,9 +26,6 @@
 
 #include <nvgpu/hw/gk20a/hw_ccsr_gk20a.h>
 
-#define NVGPU_TSG_MIN_TIMESLICE_US 1000
-#define NVGPU_TSG_MAX_TIMESLICE_US 50000
-
 struct tsg_private {
         struct gk20a *g;
         struct tsg_gk20a *tsg;
@@ -367,8 +364,8 @@ int gk20a_tsg_set_timeslice(struct tsg_gk20a *tsg, u32 timeslice)
 {
         struct gk20a *g = tsg->g;
 
-        if (timeslice < NVGPU_TSG_MIN_TIMESLICE_US ||
-                timeslice > NVGPU_TSG_MAX_TIMESLICE_US)
+        if (timeslice < g->min_timeslice_us ||
+                timeslice > g->max_timeslice_us)
                 return -EINVAL;
 
         gk20a_channel_get_timescale_from_timeslice(g, timeslice,
diff --git a/drivers/gpu/nvgpu/nvgpu_common.c b/drivers/gpu/nvgpu/nvgpu_common.c
index a2673b26..7c12616f 100644
--- a/drivers/gpu/nvgpu/nvgpu_common.c
+++ b/drivers/gpu/nvgpu/nvgpu_common.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2016-2017, 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,
@@ -69,6 +69,9 @@ static void nvgpu_init_timeslice(struct gk20a *g)
         g->timeslice_low_priority_us = 1300;
         g->timeslice_medium_priority_us = 2600;
         g->timeslice_high_priority_us = 5200;
+
+        g->min_timeslice_us = 1000;
+        g->max_timeslice_us = 50000;
 }
 
 static void nvgpu_init_pm_vars(struct gk20a *g)