gpu: sysfs mode for allowing access to registers

Through this sysfs entry, the register space becomes accessible.
This is be accessible root-only.

Bug 1523403

Change-Id: Ia46f130a0cfd8324c5b675d19e7cbfba9dcb17ca
Signed-off-by: sujeet baranwal <sbaranwal@nvidia.com>
Reviewed-on: http://git-master/r/454198
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Tested-by: Terje Bergstrom <tbergstrom@nvidia.com>

4 files changed, 43 insertions, 1 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/gk20a.h b/drivers/gpu/nvgpu/gk20a/gk20a.h
index a82ad254..3d93ccde 100644
--- a/drivers/gpu/nvgpu/gk20a/gk20a.h
+++ b/drivers/gpu/nvgpu/gk20a/gk20a.h
@@ -289,6 +289,7 @@ struct gk20a {
         bool aelpg_enabled;
         bool forced_idle;
         bool forced_reset;
+        bool allow_all;
 
 #ifdef CONFIG_DEBUG_FS
         spinlock_t debugfs_lock;
diff --git a/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c b/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c
index 97a0452c..7e0183ca 100644
--- a/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c
+++ b/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c
@@ -439,6 +439,36 @@ static ssize_t aelpg_enable_read(struct device *device,
 static DEVICE_ATTR(aelpg_enable, ROOTRW,
                 aelpg_enable_read, aelpg_enable_store);
 
+
+static ssize_t allow_all_enable_read(struct device *device,
+                struct device_attribute *attr, char *buf)
+{
+        struct platform_device *ndev = to_platform_device(device);
+        struct gk20a *g = get_gk20a(ndev);
+        return sprintf(buf, "%d\n", g->allow_all ? 1 : 0);
+}
+
+static ssize_t allow_all_enable_store(struct device *device,
+                struct device_attribute *attr, const char *buf, size_t count)
+{
+        struct platform_device *ndev = to_platform_device(device);
+        struct gk20a *g = get_gk20a(ndev);
+        unsigned long val = 0;
+        int err;
+
+        if (kstrtoul(buf, 10, &val) < 0)
+                return -EINVAL;
+
+        err = gk20a_busy(g->dev);
+        g->allow_all = (val ? true : false);
+        gk20a_idle(g->dev);
+
+        return count;
+}
+
+static DEVICE_ATTR(allow_all, ROOTRW,
+                allow_all_enable_read, allow_all_enable_store);
+
 #ifdef CONFIG_PM_RUNTIME
 static ssize_t force_idle_store(struct device *device,
         struct device_attribute *attr, const char *buf, size_t count)
@@ -509,6 +539,7 @@ void gk20a_remove_sysfs(struct device *dev)
 #endif
         device_remove_file(dev, &dev_attr_aelpg_param);
         device_remove_file(dev, &dev_attr_aelpg_enable);
+        device_remove_file(dev, &dev_attr_allow_all);
 
         if (g->host1x_dev && (dev->parent != &g->host1x_dev->dev))
                 sysfs_remove_link(&dev->kobj, dev_name(dev));
@@ -534,6 +565,7 @@ void gk20a_create_sysfs(struct platform_device *dev)
 #endif
         error |= device_create_file(&dev->dev, &dev_attr_aelpg_param);
         error |= device_create_file(&dev->dev, &dev_attr_aelpg_enable);
+        error |= device_create_file(&dev->dev, &dev_attr_allow_all);
 
         if (g->host1x_dev && (dev->dev.parent != &g->host1x_dev->dev))
                 error |= sysfs_create_link(&g->host1x_dev->dev.kobj,
diff --git a/drivers/gpu/nvgpu/gk20a/gr_gk20a.c b/drivers/gpu/nvgpu/gk20a/gr_gk20a.c
index d9ab99a4..874b8056 100644
--- a/drivers/gpu/nvgpu/gk20a/gr_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/gr_gk20a.c
@@ -1713,8 +1713,13 @@ int gr_gk20a_load_golden_ctx_image(struct gk20a *g,
         virt_addr_hi =
                  u64_hi32(ch_ctx->global_ctx_buffer_va[PRIV_ACCESS_MAP_VA]);
 
+        if (g->allow_all)
+                data = ctxsw_prog_main_image_priv_access_map_config_mode_allow_all_f();
+        else
+                data = ctxsw_prog_main_image_priv_access_map_config_mode_use_map_f();
+
         gk20a_mem_wr32(ctx_ptr + ctxsw_prog_main_image_priv_access_map_config_o(), 0,
-                 ctxsw_prog_main_image_priv_access_map_config_mode_use_map_f());
+                 data);
         gk20a_mem_wr32(ctx_ptr + ctxsw_prog_main_image_priv_access_map_addr_lo_o(), 0,
                  virt_addr_lo);
         gk20a_mem_wr32(ctx_ptr + ctxsw_prog_main_image_priv_access_map_addr_hi_o(), 0,
diff --git a/drivers/gpu/nvgpu/gk20a/hw_ctxsw_prog_gk20a.h b/drivers/gpu/nvgpu/gk20a/hw_ctxsw_prog_gk20a.h
index 747566f0..3d9095a8 100644
--- a/drivers/gpu/nvgpu/gk20a/hw_ctxsw_prog_gk20a.h
+++ b/drivers/gpu/nvgpu/gk20a/hw_ctxsw_prog_gk20a.h
@@ -214,6 +214,10 @@ static inline u32 ctxsw_prog_main_image_priv_access_map_config_mode_v(u32 r)
 {
         return (r >> 0) & 0x3;
 }
+static inline u32 ctxsw_prog_main_image_priv_access_map_config_mode_allow_all_f(void)
+{
+        return 0x0;
+}
 static inline u32 ctxsw_prog_main_image_priv_access_map_config_mode_use_map_f(void)
 {
         return 0x2;