DCE-KMD: Add support for logging infra

- Allocate DMA mapped buffer from DCE-KMD and pass it to DCE FW through
  admin-cmd calls.
- Add debugfs node to retrieve buffer data and print through seq file.
- Add support to clear log buffer

JIRA TDS-15963

Change-Id: Ied4ffe1df14c8db61cfe15e6442f55e8306530b8
Signed-off-by: jaiyasha <jaiyasha@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nv-oot/+/3117241
GVS: buildbot_gerritrpt <buildbot_gerritrpt@nvidia.com>
Reviewed-by: Mahesh Kumar <mahkumar@nvidia.com>
Tested-by: Mahesh Kumar <mahkumar@nvidia.com>
Reviewed-by: Vinod Gopalakrishnakurup <vinodg@nvidia.com>

drivers/platform/tegra/dce/Makefile

@@ -32,6 +32,7 @@ tegra-dce-$(CONFIG_TEGRA_DCE) += dce-admin.o
 tegra-dce-$(CONFIG_TEGRA_DCE) += dce-ipc.o
 tegra-dce-$(CONFIG_TEGRA_DCE) += dce-ipc-signal.o
 tegra-dce-$(CONFIG_TEGRA_DCE) += dce-client-ipc.o
+tegra-dce-$(CONFIG_TEGRA_DCE) += dce-logging.o
 tegra-dce-$(CONFIG_TEGRA_DCE) += dce-module.o
 tegra-dce-$(CONFIG_TEGRA_DCE) += dce-pm.o
 tegra-dce-$(CONFIG_TEGRA_DCE) += dce-os-work.o
@@ -42,6 +43,7 @@ tegra-dce-$(CONFIG_TEGRA_DCE) += dce-os-ivc.o
 
 ifeq ($(CONFIG_DEBUG_FS),y)
 tegra-dce-$(CONFIG_TEGRA_DCE) += dce-debug.o
+tegra-dce-$(CONFIG_TEGRA_DCE) += dce-debug-logging.o
 tegra-dce-$(CONFIG_TEGRA_DCE) += dce-admin-debug.o
 tegra-dce-$(CONFIG_TEGRA_DCE) += dce-debug-perf.o
 endif

drivers/platform/tegra/dce/dce-admin.c

@@ -25,6 +25,7 @@
 #include <dce.h>
 #include <dce-mailbox.h>
 #include <dce-os-utils.h>
+#include <dce-logging.h>
 #include <dce-client-ipc-internal.h>
 #include <interface/dce-core-interface-errors.h>
 #include <interface/dce-interface.h>
@@ -532,6 +533,12 @@ int dce_admin_init(struct tegra_dce *d)
 		goto err_ipc_reg_alloc;
 	}
 
+	ret = dce_log_buf_mem_init(d);
+	if (ret) {
+		dce_os_err(d, "dce log buf mem init failed");
+		goto err_log_buf_alloc;
+	}
+
 	ret = dce_admin_channel_init(d);
 	if (ret) {
 		dce_os_err(d, "Channel Initialization Failed");
@@ -553,6 +560,7 @@ err_channel_init:
 	dce_os_ipc_deinit_region_info(d);
 err_ipc_reg_alloc:
 	d->boot_status |= DCE_EARLY_INIT_FAILED;
+err_log_buf_alloc:
 	return ret;
 }
 
@@ -901,6 +909,56 @@ out:
 	return ret;
 }
 
+int dce_admin_get_log_info(struct tegra_dce *d, struct dce_ipc_message *msg)
+{
+	int ret = -1;
+	struct dce_admin_ipc_cmd *req_msg;
+	struct dce_admin_ipc_resp *resp_msg;
+
+	if (msg == NULL) {
+		dce_os_err(d, "Invalid params passed in get log call");
+		goto out;
+	}
+
+	req_msg = (struct dce_admin_ipc_cmd *)(msg->tx.data);
+	resp_msg = (struct dce_admin_ipc_resp *)(msg->rx.data);
+
+	req_msg->cmd = (uint32_t)DCE_ADMIN_CMD_GET_LOG_INFO;
+
+	ret = dce_admin_send_msg(d, msg);
+	if (ret) {
+		dce_os_err(d, "Error in sending get log call msg : [%d]", ret);
+		goto out;
+	}
+
+out:
+	return ret;
+}
+
+int dce_admin_set_log_info(struct tegra_dce *d, struct dce_ipc_message *msg)
+{
+	int ret = -1;
+	struct dce_admin_ipc_cmd *req_msg;
+
+	if (msg == NULL) {
+		dce_os_err(d, "Invalid params passed in set log call");
+		goto out;
+	}
+
+	req_msg = (struct dce_admin_ipc_cmd *)(msg->tx.data);
+
+	req_msg->cmd = (uint32_t)DCE_ADMIN_CMD_SET_LOGGING;
+
+	ret = dce_admin_send_msg(d, msg);
+	if (ret) {
+		dce_os_err(d, "Error in sending set log call msg : [%d]", ret);
+		goto out;
+	}
+
+out:
+	return ret;
+}
+
 static int dce_admin_setup_clients_ipc(struct tegra_dce *d,
 		struct dce_ipc_message *msg)
 {
@@ -1013,6 +1071,12 @@ int dce_start_admin_seq(struct tegra_dce *d)
 		goto out;
 	}
 
+	ret = dce_log_init(d, msg);
+	if (ret) {
+		dce_os_err(d, "RPC failed for DCE_ADMIN_CMD_SET_LOGGING");
+		goto out;
+	}
+
 	ret = dce_admin_send_rm_bootstrap(d, msg);
 	if (ret) {
 		dce_os_err(d, "RPC failed for DCE_ADMIN_CMD_RM_BOOTSTRAP");

drivers/platform/tegra/dce/dce-debug-logging.c

@@ -0,0 +1,154 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * SPDX-FileCopyrightText: Copyright (c) 2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+ */
+
+#include <linux/errno.h>
+#include <linux/debugfs.h>
+#include <linux/uaccess.h>
+
+#include <dce-os-utils.h>
+#include <dce-debug-logging.h>
+#include <dce-os-log.h>
+#include <dce-logging.h>
+#include <dce.h>
+
+static int dbg_dce_log_help_fops_show(struct seq_file *s, void *data)
+{
+/**
+ * Writing:
+ * '0' to /sys/kernel/debug/tegra_dce/dce_logs/logs
+ *    - Clear the circular buffer region data.
+ *
+ * Reading:
+ *  cat /sys/kernel/debug/tegra_dce/dce_logs/logs
+ *    - Prints the data stored in the buffer.
+ *    - Current size of buffer is 512KB and on overflow starts overwriting the circular
+ *		portion of the buffer in FIFO manner
+ */
+	seq_printf(s, " DCE logs capture\n"
+				"---------------------------------------------------------------\n"
+				" echo '0' > dce_logs/logs: Clear circular region of buffer\n"
+				"---------------------------------------------------------------\n"
+				" cat dce_logs/logs: Print buffer data\n"
+				"---------------------------------------------------------------\n");
+	return 0;
+}
+
+int dbg_dce_log_help_fops_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, dbg_dce_log_help_fops_show,
+			   inode->i_private);
+}
+
+static int dbg_dce_log_fops_show(struct seq_file *s, void *data)
+{
+	int ret = 0;
+	uint32_t offset;
+	uint64_t bytes_written;
+	uint32_t cur_buf_idx;
+	struct tegra_dce *d				= s->private;
+	char *base_addr					= (char *)d->dce_log_buff.cpu_base;
+	uint32_t log_buf_size			= d->dce_log_buff.size;
+	struct dce_ipc_message *msg		= NULL;
+	struct dce_admin_ipc_resp *resp_msg;
+
+	msg = dce_admin_channel_client_buffer_get(d, DCE_ADMIN_CH_CL_DBG_BUFF,
+		0 /* reserved flags */);
+
+	if (!msg) {
+		ret = -1;
+		dce_os_err(d, "IPC msg allocation failed");
+		goto out;
+	}
+
+	/** Retrieve logging info */
+	ret = dce_admin_get_log_info(d, msg);
+	if (ret) {
+		dce_os_err(d, "Failed to retrieve logging info, ret = 0x%x", ret);
+		goto out;
+	}
+
+	resp_msg = (struct dce_admin_ipc_resp *) (msg->rx.data);
+
+	bytes_written	= resp_msg->args.log.get_log_info.bytes_written;
+	offset			= resp_msg->args.log.get_log_info.offset;
+
+	/** If complete buffer size is zero then buffer is invalid */
+	if (log_buf_size == 0) {
+		seq_printf(s, "%s", "Invalid log buffer\n");
+		goto out;
+	}
+
+	if (bytes_written == 0U || (log_buf_size <= offset)) {
+		seq_printf(s, "%.*s", offset, base_addr);
+		goto out;
+	}
+
+	/** Find total bytes written currently in circular region of buffer */
+	cur_buf_idx = (bytes_written)%(log_buf_size - offset);
+
+	/** If circular buffer is not yet wrapped around */
+	if (bytes_written <= log_buf_size - offset) {
+		seq_printf(s, "%.*s", offset, base_addr);
+		seq_printf(s, "%.*s", cur_buf_idx, base_addr + offset);
+		goto out;
+	}
+
+	/** If circular buffer region has been overwritten */
+	/** Print initial logs till offset */
+	seq_printf(s, "%.*s", offset, base_addr);
+	/** Print logs stored in circular buffer region */
+	seq_printf(s, "%.*s", log_buf_size - cur_buf_idx - offset, base_addr + offset + cur_buf_idx);
+	seq_printf(s, "%.*s", cur_buf_idx, base_addr + offset);
+
+out:
+	if (msg)
+		dce_admin_channel_client_buffer_put(d, msg);
+	return ret;
+}
+
+int dbg_dce_log_fops_open(struct inode *inode, struct file *file)
+{
+	size_t seq_buf_size = 100*PAGE_SIZE;
+
+	return single_open_size(file, &dbg_dce_log_fops_show, inode->i_private, seq_buf_size);
+}
+
+ssize_t dbg_dce_log_fops_write(struct file *file, const char __user *user_buf,
+				size_t count, loff_t *ppos)
+{
+	int ret = 0;
+	char buf[32];
+	uint32_t buf_size;
+	uint32_t log_op;
+	struct dce_ipc_message *msg = NULL;
+	struct tegra_dce *d = ((struct seq_file *)file->private_data)->private;
+
+	buf_size = min(count, (sizeof(buf)-1));
+
+	msg = dce_admin_channel_client_buffer_get(d, DCE_ADMIN_CH_CL_DBG_BUFF,
+		0 /* reserved flags */);
+	if (!msg) {
+		dce_os_err(d, "IPC msg allocation failed");
+		goto out;
+	}
+
+	ret = kstrtou32_from_user(user_buf, buf_size, 10, &log_op);
+	if (ret) {
+		dce_os_err(d, "Invalid format!");
+		goto out;
+	}
+
+	if (log_op == 0U) {
+		dce_os_err(d, "Clearing circular region of log buffer");
+		ret = dce_log_clear_buffer(d, msg);
+		if (ret)
+			dce_os_err(d, "Failed to clear log buffer!");
+	}
+
+out:
+	if (msg)
+		dce_admin_channel_client_buffer_put(d, msg);
+	return count;
+}

drivers/platform/tegra/dce/dce-debug.c

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0-only
 /*
- * SPDX-FileCopyrightText: Copyright (c) 2019-2024 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+ * SPDX-FileCopyrightText: Copyright (c) 2019-2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
  */
 
 #include <linux/errno.h>
@@ -12,6 +12,7 @@
 #include <dce-os-utils.h>
 #include <dce-linux-device.h>
 #include <dce-debug-perf.h>
+#include <dce-debug-logging.h>
 #include <interface/dce-interface.h>
 #include <interface/dce-core-interface-errors.h>
 
@@ -162,6 +163,21 @@ static const struct file_operations load_firmware_fops = {
 	.write =	dbg_dce_load_fw_write,
 };
 
+static const struct file_operations dbg_dce_log_help_fops = {
+	.open		=	dbg_dce_log_help_fops_open,
+	.read		=	seq_read,
+	.llseek		=	seq_lseek,
+	.release	=	single_release,
+};
+
+static const struct file_operations dbg_dce_log_fops = {
+	.open		=	dbg_dce_log_fops_open,
+	.read		=	seq_read,
+	.llseek		=	seq_lseek,
+	.release	=	single_release,
+	.write		=	dbg_dce_log_fops_write,
+};
+
 static ssize_t dbg_dce_config_ast_read(struct file *file,
 			char __user *user_buf, size_t count, loff_t *ppos)
 {
@@ -764,6 +780,7 @@ void dce_init_debug(struct tegra_dce *d)
 	struct dce_linux_device *d_dev = dce_linux_device_from_dce(d);
 	struct dentry *debugfs_dir = NULL;
 	struct dentry *perf_debugfs_dir = NULL;
+	struct dentry *dce_logging_dir = NULL;
 	int ret = 0;
 
 	ret = dce_admin_channel_client_buffers_init(d, DCE_ADMIN_CH_CL_DBG_BUFF);
@@ -781,6 +798,20 @@ void dce_init_debug(struct tegra_dce *d)
 	if (!retval)
 		goto err_handle;
 
+	dce_logging_dir = debugfs_create_dir("dce_logs", d_dev->debugfs);
+	if (!dce_logging_dir)
+		goto err_handle;
+
+	retval = debugfs_create_file("help", 0444,
+					dce_logging_dir, d, &dbg_dce_log_help_fops);
+	if (!retval)
+		goto err_handle;
+
+	retval = debugfs_create_file("logs", 0644,
+					dce_logging_dir, d, &dbg_dce_log_fops);
+	if (!retval)
+		goto err_handle;
+
 	retval = debugfs_create_file("config_ast", 0444,
 				     d_dev->debugfs, d, &config_ast_fops);
 	if (!retval)

drivers/platform/tegra/dce/dce-logging.c

@@ -0,0 +1,113 @@
+// SPDX-License-Identifier: MIT
+/*
+ * SPDX-FileCopyrightText: Copyright (c) 2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#include <dce.h>
+#include <dce-logging.h>
+#include <dce-os-utils.h>
+
+int dce_log_buf_mem_init(struct tegra_dce *d)
+{
+	int ret = 0;
+
+	ret = dce_os_init_log_buffer(d);
+	if (ret) {
+		dce_os_err(d, "Failed to allocate memory for DCE log buffer");
+		goto out;
+	}
+
+out:
+	if (ret)
+		dce_os_deinit_log_buffer(d);
+	return ret;
+}
+
+int dce_log_init(struct tegra_dce *d, struct dce_ipc_message *msg)
+{
+	int ret = -1;
+	struct dce_log_buffer *buffer;
+	struct dce_admin_ipc_cmd		*req_msg;
+	struct dce_admin_set_log_info	*set_info;
+
+	req_msg = (struct dce_admin_ipc_cmd *)(msg->tx.data);
+	set_info = (struct dce_admin_set_log_info *)(&req_msg->args.log.set_log_info);
+
+	buffer				= &d->dce_log_buff;
+	set_info->flags		= DCE_ADMIN_LOG_FL_SET_IOVA_ADDR | DCE_ADMIN_LOG_FL_SET_LOG_LVL;
+	set_info->iova		= buffer->iova_addr;
+	set_info->buff_size	= buffer->size;
+	set_info->log_level	= (uint32_t)DCE_LOG_DEFAULT_LOG_LVL;
+	set_info->stream_id	= dce_os_get_dce_stream_id(d);
+
+	ret = dce_admin_set_log_info(d, msg);
+	if (ret) {
+		dce_os_err(d, "Failed to initialize logging, ret = %d\n", ret);
+		goto out;
+	}
+
+out:
+	return ret;
+}
+
+int dce_log_clear_buffer(struct tegra_dce *d, struct dce_ipc_message *msg)
+{
+	int ret = -1;
+	struct dce_admin_ipc_cmd		*req_msg;
+	struct dce_admin_set_log_info	*ipc_info;
+
+	req_msg = (struct dce_admin_ipc_cmd *)(msg->tx.data);
+	ipc_info = (struct dce_admin_set_log_info *)(&req_msg->args.log.set_log_info);
+
+	ipc_info->flags |= DCE_ADMIN_LOG_FL_CLEAR_BUFFER;
+
+	ret = dce_admin_set_log_info(d, msg);
+	if (ret) {
+		dce_os_err(d, "Failed while making set admin call, ret = %d\n", ret);
+		goto out;
+	}
+
+out:
+	return ret;
+}
+
+int dce_log_set_log_level(struct tegra_dce *d, struct dce_ipc_message *msg,
+						u32 log_lvl)
+{
+	int ret = -1;
+	struct dce_admin_ipc_cmd		*req_msg;
+	struct dce_admin_set_log_info	*ipc_info;
+
+	req_msg = (struct dce_admin_ipc_cmd *)(msg->tx.data);
+	ipc_info = (struct dce_admin_set_log_info *)(&req_msg->args.log.set_log_info);
+
+	ipc_info->flags |= DCE_ADMIN_LOG_FL_SET_LOG_LVL;
+	ipc_info->log_level = log_lvl;
+
+	ret = dce_admin_set_log_info(d, msg);
+	if (ret) {
+		dce_os_err(d, "Failed while making set admin call, ret = %d\n", ret);
+		goto out;
+	}
+
+out:
+	return ret;
+}

drivers/platform/tegra/dce/dce-os-utils.c

@@ -570,3 +570,32 @@ void dce_os_bitmap_clear(unsigned long *map,
 {
 	bitmap_clear(map, start, (int)len);
 }
+
+int dce_os_init_log_buffer(struct tegra_dce *d)
+{
+	struct dce_log_buffer *buffer;
+	struct device *dev = dev_from_dce_linux_device(d);
+
+	buffer = &d->dce_log_buff;
+	buffer->size = SZ_512K; // Allocate 512KB for log buffer
+
+	buffer->cpu_base = dma_alloc_coherent(dev, buffer->size, &buffer->iova_addr,
+								GFP_KERNEL);
+
+	if (!buffer->iova_addr)
+		return -ENOMEM;
+
+	return 0;
+}
+
+void dce_os_deinit_log_buffer(struct tegra_dce *d)
+{
+	struct dce_log_buffer *buffer;
+	struct device *dev = dev_from_dce_linux_device(d);
+
+	buffer = &d->dce_log_buff;
+	if (buffer->iova_addr) {
+		dma_free_coherent(dev, buffer->size, (void *)buffer->cpu_base,
+					buffer->iova_addr);
+	}
+}

drivers/platform/tegra/dce/include/dce-debug-logging.h

@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * SPDX-FileCopyrightText: Copyright (c) 2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+ */
+
+#ifndef DCE_DEBUG_LOGGING_H
+#define DCE_DEBUG_LOGGING_H
+
+#include <dce-os-types.h>
+
+int dbg_dce_log_help_fops_open(struct inode *inode, struct file *file);
+
+int dbg_dce_log_fops_open(struct inode *inode, struct file *file);
+
+ssize_t dbg_dce_log_fops_write(struct file *file,
+			       const char __user *user_buf,
+			       size_t count, loff_t *ppos);
+
+#endif /* DCE_DEBUG_LOGGING_H */

drivers/platform/tegra/dce/include/dce-logging.h

@@ -0,0 +1,62 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * SPDX-FileCopyrightText: Copyright (c) 2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef DCE_LOGGING_H
+#define DCE_LOGGING_H
+
+#include <interface/dce-admin-cmds.h>
+#include <dce.h>
+
+typedef uint8_t         dce_log_set_log_flags_t;
+
+#define DCE_LOG_FL_CLEAR_BUFFER     ((dce_log_set_log_flags_t)1U)
+#define DCE_LOG_FL_SET_IOVA_ADDR    ((dce_log_set_log_flags_t)2U)
+#define DCE_LOG_FL_SET_LOG_LVL      ((dce_log_set_log_flags_t)4U)
+
+typedef uint32_t        dce_log_set_log_lvl_t;
+
+#define DCE_LOG_MAX_LOG_LVL			((dce_log_set_log_lvl_t)7U)
+#define DCE_LOG_DEFAULT_LOG_LVL		((dce_log_set_log_lvl_t)0xFFFFFFFFU)
+
+/**
+ * @brief Allocate memory for DCE logging buffer
+ */
+int dce_log_buf_mem_init(struct tegra_dce *d);
+
+/**
+ * @brief Initialize set log struct while doing log buffer initialization
+ */
+int dce_log_init(struct tegra_dce *d, struct dce_ipc_message *msg);
+
+/**
+ * @brief Clear circular region of log buffer
+ */
+int dce_log_clear_buffer(struct tegra_dce *d, struct dce_ipc_message *msg);
+
+/**
+ * @brief Set log level for logging to log buffer
+ */
+int dce_log_set_log_level(struct tegra_dce *d, struct dce_ipc_message *msg,
+					u32 log_lvl);
+
+#endif /* DCE_LOGGING_H */

drivers/platform/tegra/dce/include/dce.h

@@ -200,6 +200,19 @@ struct dce_firmware {
 	u64 dma_handle;
 };
 
+/**
+ * struct dce_log_buffer - Contains dce log buffer info
+ *
+ * @iova_addr : iova address of the buffer
+ * @size : size of the buffer
+ * @base : cpu base address of the buffer
+ */
+struct dce_log_buffer {
+	dma_addr_t iova_addr;
+	size_t size;
+	void *cpu_base;
+};
+
 /**
  * struct tegra_dce - Primary OS independent tegra dce structure to hold dce
  * cluster's and it's element's runtime info.
@@ -287,6 +300,10 @@ struct tegra_dce {
 	 * @fw_data - Stores info regardign firmware to be used runtime.
 	 */
 	struct dce_firmware *fw_data;
+	/**
+	 * @dce_log_buffer_struct - Stores info regarding DCE log buffer
+	 */
+	struct dce_log_buffer dce_log_buff;
 	/**
 	 * @dce_admin_ch_cl_buff - Stores admin channel client buffers.
 	 */
@@ -424,6 +441,8 @@ int dce_admin_send_cmd_clear_perf_events(struct tegra_dce *d,
 				       struct dce_ipc_message *msg);
 int dce_admin_ipc_wait(struct tegra_dce *d);
 void dce_admin_ipc_handle_signal(struct tegra_dce *d, u32 ch_type);
+int dce_admin_set_log_info(struct tegra_dce *d, struct dce_ipc_message *msg);
+int dce_admin_get_log_info(struct tegra_dce *d, struct dce_ipc_message *msg);
 
 bool dce_fw_boot_complete(struct tegra_dce *d);
 void dce_request_fw_boot_complete(struct tegra_dce *d);

drivers/platform/tegra/dce/os/include/dce-os-utils.h

@@ -64,4 +64,8 @@ void dce_os_bitmap_clear(unsigned long *map,
 
 u8 dce_os_get_dce_stream_id(struct tegra_dce *d);
 
+int dce_os_init_log_buffer(struct tegra_dce *d);
+
+void dce_os_deinit_log_buffer(struct tegra_dce *d);
+
 #endif /* DCE_OS_UTILS_H */