diff --git a/drivers/gpu/nvgpu/include/nvgpu/gk20a.h b/drivers/gpu/nvgpu/include/nvgpu/gk20a.h
index ac03a6980..36c18cd6b 100644
--- a/drivers/gpu/nvgpu/include/nvgpu/gk20a.h
+++ b/drivers/gpu/nvgpu/include/nvgpu/gk20a.h
@@ -40,6 +40,7 @@
  *   - @ref unit-sdl
  *   - @ref unit-init
  *   - @ref unit-falcon
+ *   - @ref unit-os_utils
  *   - Etc, etc.
  *
  * NVGPU Software Unit Design Documentation
diff --git a/drivers/gpu/nvgpu/include/nvgpu/io.h b/drivers/gpu/nvgpu/include/nvgpu/io.h
index d0dcaa6e4..161e665e6 100644
--- a/drivers/gpu/nvgpu/include/nvgpu/io.h
+++ b/drivers/gpu/nvgpu/include/nvgpu/io.h
@@ -35,9 +35,36 @@
 
 struct gk20a;
 
+/**
+ * @brief Write a value to an already mapped io-region.
+ *
+ * @param g[in]		GPU super structure.
+ * @param r[in]		Register offset in io-region.
+ * @param v[in]		Value to write at the offset.
+ *
+ * @return None.
+ */
 void nvgpu_writel(struct gk20a *g, u32 r, u32 v);
 void nvgpu_writel_relaxed(struct gk20a *g, u32 r, u32 v);
+
+/**
+ * @brief Read a value from an already mapped io-region.
+ *
+ * @param g[in]		GPU super structure.
+ * @param r[in]		Register offset in io-region.
+ *
+ * @return Value at the given offset of the io-region.
+ */
 u32 nvgpu_readl(struct gk20a *g, u32 r);
+
+/**
+ * @brief Read a value from an already mapped io-region.
+ *
+ * @param g[in]		GPU super structure.
+ * @param r[in]		Register offset in io-region.
+ *
+ * @return Value at the given offset of the io-region.
+ */
 u32 nvgpu_readl_impl(struct gk20a *g, u32 r);
 void nvgpu_writel_check(struct gk20a *g, u32 r, u32 v);
 void nvgpu_writel_loop(struct gk20a *g, u32 r, u32 v);
diff --git a/drivers/gpu/nvgpu/include/nvgpu/soc.h b/drivers/gpu/nvgpu/include/nvgpu/soc.h
index e4a040f23..9abe93fe6 100644
--- a/drivers/gpu/nvgpu/include/nvgpu/soc.h
+++ b/drivers/gpu/nvgpu/include/nvgpu/soc.h
@@ -26,13 +26,76 @@
 
 struct gk20a;
 
+/**
+ * @brief Check whether running on silicon or not.
+ *
+ * @param g[in]		GPU super structure.
+ *
+ * @return Returns true if it's silicon else return false.
+ */
 bool nvgpu_platform_is_silicon(struct gk20a *g);
+
+/**
+ * @brief Check whether running simulation or not.
+ *
+ * @param g[in]		GPU super structure.
+ *
+ * @return Returns true if it's simulation else returns false.
+ */
 bool nvgpu_platform_is_simulation(struct gk20a *g);
+
+/**
+ * @brief Check whether running fpga or not.
+ *
+ * @param g[in]		GPU super structure.
+ *
+ * @return Returns true if it's fpga else returns false.
+ */
 bool nvgpu_platform_is_fpga(struct gk20a *g);
+
+/**
+ * @brief Check whether running in virtualized environment.
+ *
+ * @param g[in]		GPU super structure.
+ *
+ * @return Returns true if it's virtualized environment else returns false.
+ */
 bool nvgpu_is_hypervisor_mode(struct gk20a *g);
+
+/**
+ * @brief Check whether bpmp server is runing.
+ *
+ * @param g[in]		GPU super structure.
+ *
+ * @return Returns true if bpmp server is running else returns false.
+ */
 bool nvgpu_is_bpmp_running(struct gk20a *g);
+
+/**
+ * @brief Check whether soc is t194 and revision a01.
+ *
+ * @param g[in]		GPU super structure.
+ *
+ * @return Returns true if soc is t194-a01 else returns false.
+ */
 bool nvgpu_is_soc_t194_a01(struct gk20a *g);
+
+/**
+ * @brief Do soc related init
+ *
+ * @param g[in]		GPU super structure.
+ *
+ * @return Returns 0 on success or in case of failure, a suitable error code.
+ */
 int nvgpu_init_soc_vars(struct gk20a *g);
+
+/**
+ * @brief OS specific implementation to provide precise microsecond delay
+ *
+ * @param usecs[in]		Delay in microseconds.
+ *
+ * @return None.
+ */
 void nvgpu_delay_usecs(unsigned int usecs);
 u64 nvgpu_us_counter(void);
 u64 nvgpu_get_cycles(void);