drivers/hid/intel-ish-hid/ishtp/loader.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * ISHTP firmware loader function
  *
  * Copyright (c) 2024, Intel Corporation.
  *
  * This module implements the functionality to load the main ISH firmware from the host, starting
  * with the Lunar Lake generation. It leverages a new method that enhances space optimization and
  * flexibility by dividing the ISH firmware into a bootloader and main firmware.
  *
  * Please refer to the [Documentation](Documentation/hid/intel-ish-hid.rst) for the details on
  * flows.
  *
  * Additionally, address potential error scenarios to ensure graceful failure handling.
  * - Firmware Image Not Found:
  *   Occurs when `request_firmware()` cannot locate the firmware image. The ISH firmware will
  *   remain in a state awaiting firmware loading from the host, with no further action from
  *   the ISHTP driver.
  *   Recovery: Re-insmod the ISH drivers allows for a retry of the firmware loading from the host.
  *
  * - DMA Buffer Allocation Failure:
  *   This happens if allocating a DMA buffer during `prepare_dma_bufs()` fails. The ISH firmware
  *   will stay in a waiting state, and the ISHTP driver will release any allocated DMA buffers and
  *   firmware without further actions.
  *   Recovery: Re-insmod the ISH drivers allows for a retry of the firmware loading from the host.
  *
  * - Incorrect Firmware Image:
  *   Using an incorrect firmware image will initiate the firmware loading process but will
  *   eventually be refused by the ISH firmware after three unsuccessful attempts, indicated by
  *   returning an error code. The ISHTP driver will stop attempting after three tries.
  *   Recovery: A platform reset is required to retry firmware loading from the host.
  */

 #define dev_fmt(fmt) "ISH loader: " fmt

 #include <linux/cacheflush.h>
 #include <linux/container_of.h>
 #include <linux/dev_printk.h>
 #include <linux/dma-mapping.h>
 #include <linux/errno.h>
 #include <linux/firmware.h>
 #include <linux/gfp_types.h>
 #include <linux/math.h>
 #include <linux/module.h>
 #include <linux/pfn.h>
 #include <linux/string.h>
 #include <linux/types.h>
 #include <linux/wait.h>

 #include "hbm.h"
 #include "loader.h"

 /**
  * loader_write_message() - Write a message to the ISHTP device
  * @dev: The ISHTP device
  * @buf: The buffer containing the message
  * @len: The length of the message
  *
  * Return: 0 on success, negative error code on failure
  */
 static int loader_write_message(struct ishtp_device *dev, void *buf, int len)
 {
 	struct ishtp_msg_hdr ishtp_hdr = {
 		.fw_addr = ISHTP_LOADER_CLIENT_ADDR,
 		.length = len,
 		.msg_complete = 1,
 	};

 	dev->fw_loader_received = false;

 	return ishtp_write_message(dev, &ishtp_hdr, buf);
 }

 /**
  * loader_xfer_cmd() - Transfer a command to the ISHTP device
  * @dev: The ISHTP device
  * @req: The request buffer
  * @req_len: The length of the request
  * @resp: The response buffer
  * @resp_len: The length of the response
  *
  * Return: 0 on success, negative error code on failure
  */
 static int loader_xfer_cmd(struct ishtp_device *dev, void *req, int req_len,
 			   void *resp, int resp_len)
 {
 	struct loader_msg_header *req_hdr = req;
 	struct loader_msg_header *resp_hdr = resp;
 	struct device *devc = dev->devc;
 	int rv;

 	dev->fw_loader_rx_buf = resp;
 	dev->fw_loader_rx_size = resp_len;

 	rv = loader_write_message(dev, req, req_len);
 	if (rv < 0) {
 		dev_err(devc, "write cmd %u failed:%d\n", req_hdr->command, rv);
 		return rv;
 	}

 	/* Wait the ACK */
 	wait_event_interruptible_timeout(dev->wait_loader_recvd_msg, dev->fw_loader_received,
 					 ISHTP_LOADER_TIMEOUT);
 	dev->fw_loader_rx_size = 0;
 	dev->fw_loader_rx_buf = NULL;
 	if (!dev->fw_loader_received) {
 		dev_err(devc, "wait response of cmd %u timeout\n", req_hdr->command);
 		return -ETIMEDOUT;
 	}

 	if (!resp_hdr->is_response) {
 		dev_err(devc, "not a response for %u\n", req_hdr->command);
 		return -EBADMSG;
 	}

 	if (req_hdr->command != resp_hdr->command) {
 		dev_err(devc, "unexpected cmd response %u:%u\n", req_hdr->command,
 			resp_hdr->command);
 		return -EBADMSG;
 	}

 	if (resp_hdr->status) {
 		dev_err(devc, "cmd %u failed %u\n", req_hdr->command, resp_hdr->status);
 		return -EIO;
 	}

 	return 0;
 }

 /**
  * release_dma_bufs() - Release the DMA buffer for transferring firmware fragments
  * @dev: The ISHTP device
  * @fragment: The ISHTP firmware fragment descriptor
  * @dma_bufs: The array of DMA fragment buffers
  * @fragment_size: The size of a single DMA fragment
  */
 static void release_dma_bufs(struct ishtp_device *dev,
 			     struct loader_xfer_dma_fragment *fragment,
 			     void **dma_bufs, u32 fragment_size)
 {
 	int i;

 	for (i = 0; i < FRAGMENT_MAX_NUM; i++) {
 		if (dma_bufs[i]) {
 			dma_free_coherent(dev->devc, fragment_size, dma_bufs[i],
 					  fragment->fragment_tbl[i].ddr_adrs);
 			dma_bufs[i] = NULL;
 		}
 	}
 }

 /**
  * prepare_dma_bufs() - Prepare the DMA buffer for transferring firmware fragments
  * @dev: The ISHTP device
  * @ish_fw: The ISH firmware
  * @fragment: The ISHTP firmware fragment descriptor
  * @dma_bufs: The array of DMA fragment buffers
  * @fragment_size: The size of a single DMA fragment
  *
  * Return: 0 on success, negative error code on failure
  */
 static int prepare_dma_bufs(struct ishtp_device *dev,
 			    const struct firmware *ish_fw,
 			    struct loader_xfer_dma_fragment *fragment,
 			    void **dma_bufs, u32 fragment_size)
 {
 	u32 offset = 0;
 	int i;

 	for (i = 0; i < fragment->fragment_cnt && offset < ish_fw->size; i++) {
 		dma_bufs[i] = dma_alloc_coherent(dev->devc, fragment_size,
 						 &fragment->fragment_tbl[i].ddr_adrs, GFP_KERNEL);
 		if (!dma_bufs[i])
 			return -ENOMEM;

 		fragment->fragment_tbl[i].length = clamp(ish_fw->size - offset, 0, fragment_size);
 		fragment->fragment_tbl[i].fw_off = offset;
 		memcpy(dma_bufs[i], ish_fw->data + offset, fragment->fragment_tbl[i].length);
 		clflush_cache_range(dma_bufs[i], fragment_size);

 		offset += fragment->fragment_tbl[i].length;
 	}

 	return 0;
 }

 /**
  * ishtp_loader_work() - Load the ISHTP firmware
  * @work: The work structure
  *
  * The ISH Loader attempts to load firmware by sending a series of commands
  * to the ISH device. If a command fails to be acknowledged by the ISH device,
  * the loader will retry sending the command, up to a maximum of
  * ISHTP_LOADER_RETRY_TIMES.
  *
  * After the maximum number of retries has been reached without success, the
  * ISH bootloader will return an error status code and will no longer respond
  * to the driver's commands. This behavior indicates that the ISH Loader has
  * encountered a critical error during the firmware loading process.
  *
  * In such a case, where the ISH bootloader is unresponsive after all retries
  * have been exhausted, a platform reset is required to restore communication
  * with the ISH device and to recover from this error state.
  */
 void ishtp_loader_work(struct work_struct *work)
 {
 	DEFINE_RAW_FLEX(struct loader_xfer_dma_fragment, fragment, fragment_tbl, FRAGMENT_MAX_NUM);
 	struct ishtp_device *dev = container_of(work, struct ishtp_device, work_fw_loader);
 	struct loader_xfer_query query = {
 		.header.command = LOADER_CMD_XFER_QUERY,
 	};
 	struct loader_start start = {
 		.header.command = LOADER_CMD_START,
 	};
 	union loader_recv_message recv_msg;
 	char *filename = dev->driver_data->fw_filename;
 	const struct firmware *ish_fw;
 	void *dma_bufs[FRAGMENT_MAX_NUM] = {};
 	u32 fragment_size;
 	int retry = ISHTP_LOADER_RETRY_TIMES;
 	int rv;

 	rv = request_firmware(&ish_fw, filename, dev->devc);
 	if (rv < 0) {
 		dev_err(dev->devc, "request firmware %s failed:%d\n", filename, rv);
 		return;
 	}

 	fragment->fragment.header.command = LOADER_CMD_XFER_FRAGMENT;
 	fragment->fragment.xfer_mode = LOADER_XFER_MODE_DMA;
 	fragment->fragment.is_last = 1;
 	fragment->fragment.size = ish_fw->size;
 	/* Calculate the size of a single DMA fragment */
 	fragment_size = PFN_ALIGN(DIV_ROUND_UP(ish_fw->size, FRAGMENT_MAX_NUM));
 	/* Calculate the count of DMA fragments */
 	fragment->fragment_cnt = DIV_ROUND_UP(ish_fw->size, fragment_size);

 	rv = prepare_dma_bufs(dev, ish_fw, fragment, dma_bufs, fragment_size);
 	if (rv) {
 		dev_err(dev->devc, "prepare DMA buffer failed.\n");
 		goto out;
 	}

 	do {
 		query.image_size = ish_fw->size;
 		rv = loader_xfer_cmd(dev, &query, sizeof(query), recv_msg.raw_data,
 				     sizeof(struct loader_xfer_query_ack));
 		if (rv)
 			continue; /* try again if failed */

 		dev_dbg(dev->devc, "ISH Version %u.%u.%u.%u\n",
 			recv_msg.query_ack.version_major,
 			recv_msg.query_ack.version_minor,
 			recv_msg.query_ack.version_hotfix,
 			recv_msg.query_ack.version_build);

 		rv = loader_xfer_cmd(dev, fragment,
 				     struct_size(fragment, fragment_tbl, fragment->fragment_cnt),
 				     recv_msg.raw_data, sizeof(struct loader_xfer_fragment_ack));
 		if (rv)
 			continue; /* try again if failed */

 		rv = loader_xfer_cmd(dev, &start, sizeof(start), recv_msg.raw_data,
 				     sizeof(struct loader_start_ack));
 		if (rv)
 			continue; /* try again if failed */

 		dev_info(dev->devc, "firmware loaded. size:%zu\n", ish_fw->size);
 		break;
 	} while (--retry);

 out:
 	release_dma_bufs(dev, fragment, dma_bufs, fragment_size);
 	release_firmware(ish_fw);
 }
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* ISHTP firmware loader function
	*
	* Copyright (c) 2024, Intel Corporation.
	*
	* This module implements the functionality to load the main ISH firmware from the host, starting
	* with the Lunar Lake generation. It leverages a new method that enhances space optimization and
	* flexibility by dividing the ISH firmware into a bootloader and main firmware.
	*
	* Please refer to the [Documentation](Documentation/hid/intel-ish-hid.rst) for the details on
	* flows.
	*
	* Additionally, address potential error scenarios to ensure graceful failure handling.
	* - Firmware Image Not Found:
	* Occurs when `request_firmware()` cannot locate the firmware image. The ISH firmware will
	* remain in a state awaiting firmware loading from the host, with no further action from
	* the ISHTP driver.
	* Recovery: Re-insmod the ISH drivers allows for a retry of the firmware loading from the host.
	*
	* - DMA Buffer Allocation Failure:
	* This happens if allocating a DMA buffer during `prepare_dma_bufs()` fails. The ISH firmware
	* will stay in a waiting state, and the ISHTP driver will release any allocated DMA buffers and
	* firmware without further actions.
	* Recovery: Re-insmod the ISH drivers allows for a retry of the firmware loading from the host.
	*
	* - Incorrect Firmware Image:
	* Using an incorrect firmware image will initiate the firmware loading process but will
	* eventually be refused by the ISH firmware after three unsuccessful attempts, indicated by
	* returning an error code. The ISHTP driver will stop attempting after three tries.
	* Recovery: A platform reset is required to retry firmware loading from the host.
	*/

	#define dev_fmt(fmt) "ISH loader: " fmt

	#include <linux/cacheflush.h>
	#include <linux/container_of.h>
	#include <linux/dev_printk.h>
	#include <linux/dma-mapping.h>
	#include <linux/errno.h>
	#include <linux/firmware.h>
	#include <linux/gfp_types.h>
	#include <linux/math.h>
	#include <linux/module.h>
	#include <linux/pfn.h>
	#include <linux/string.h>
	#include <linux/types.h>
	#include <linux/wait.h>

	#include "hbm.h"
	#include "loader.h"

	/**
	* loader_write_message() - Write a message to the ISHTP device
	* @dev: The ISHTP device
	* @buf: The buffer containing the message
	* @len: The length of the message
	*
	* Return: 0 on success, negative error code on failure
	*/
	static int loader_write_message(struct ishtp_device dev, void buf, int len)
	{
	struct ishtp_msg_hdr ishtp_hdr = {
	.fw_addr = ISHTP_LOADER_CLIENT_ADDR,
	.length = len,
	.msg_complete = 1,
	};

	dev->fw_loader_received = false;

	return ishtp_write_message(dev, &ishtp_hdr, buf);
	}

	/**
	* loader_xfer_cmd() - Transfer a command to the ISHTP device
	* @dev: The ISHTP device
	* @req: The request buffer
	* @req_len: The length of the request
	* @resp: The response buffer
	* @resp_len: The length of the response
	*
	* Return: 0 on success, negative error code on failure
	*/
	static int loader_xfer_cmd(struct ishtp_device dev, void req, int req_len,
	void *resp, int resp_len)
	{
	struct loader_msg_header *req_hdr = req;
	struct loader_msg_header *resp_hdr = resp;
	struct device *devc = dev->devc;
	int rv;

	dev->fw_loader_rx_buf = resp;
	dev->fw_loader_rx_size = resp_len;

	rv = loader_write_message(dev, req, req_len);
	if (rv < 0) {
	dev_err(devc, "write cmd %u failed:%d\n", req_hdr->command, rv);
	return rv;
	}

	/* Wait the ACK */
	wait_event_interruptible_timeout(dev->wait_loader_recvd_msg, dev->fw_loader_received,
	ISHTP_LOADER_TIMEOUT);
	dev->fw_loader_rx_size = 0;
	dev->fw_loader_rx_buf = NULL;
	if (!dev->fw_loader_received) {
	dev_err(devc, "wait response of cmd %u timeout\n", req_hdr->command);
	return -ETIMEDOUT;
	}

	if (!resp_hdr->is_response) {
	dev_err(devc, "not a response for %u\n", req_hdr->command);
	return -EBADMSG;
	}

	if (req_hdr->command != resp_hdr->command) {
	dev_err(devc, "unexpected cmd response %u:%u\n", req_hdr->command,
	resp_hdr->command);
	return -EBADMSG;
	}

	if (resp_hdr->status) {
	dev_err(devc, "cmd %u failed %u\n", req_hdr->command, resp_hdr->status);
	return -EIO;
	}

	return 0;
	}

	/**
	* release_dma_bufs() - Release the DMA buffer for transferring firmware fragments
	* @dev: The ISHTP device
	* @fragment: The ISHTP firmware fragment descriptor
	* @dma_bufs: The array of DMA fragment buffers
	* @fragment_size: The size of a single DMA fragment
	*/
	static void release_dma_bufs(struct ishtp_device *dev,
	struct loader_xfer_dma_fragment *fragment,
	void **dma_bufs, u32 fragment_size)
	{
	int i;

	for (i = 0; i < FRAGMENT_MAX_NUM; i++) {
	if (dma_bufs[i]) {
	dma_free_coherent(dev->devc, fragment_size, dma_bufs[i],
	fragment->fragment_tbl[i].ddr_adrs);
	dma_bufs[i] = NULL;
	}
	}
	}

	/**
	* prepare_dma_bufs() - Prepare the DMA buffer for transferring firmware fragments
	* @dev: The ISHTP device
	* @ish_fw: The ISH firmware
	* @fragment: The ISHTP firmware fragment descriptor
	* @dma_bufs: The array of DMA fragment buffers
	* @fragment_size: The size of a single DMA fragment
	*
	* Return: 0 on success, negative error code on failure
	*/
	static int prepare_dma_bufs(struct ishtp_device *dev,
	const struct firmware *ish_fw,
	struct loader_xfer_dma_fragment *fragment,
	void **dma_bufs, u32 fragment_size)
	{
	u32 offset = 0;
	int i;

	for (i = 0; i < fragment->fragment_cnt && offset < ish_fw->size; i++) {
	dma_bufs[i] = dma_alloc_coherent(dev->devc, fragment_size,
	&fragment->fragment_tbl[i].ddr_adrs, GFP_KERNEL);
	if (!dma_bufs[i])
	return -ENOMEM;

	fragment->fragment_tbl[i].length = clamp(ish_fw->size - offset, 0, fragment_size);
	fragment->fragment_tbl[i].fw_off = offset;
	memcpy(dma_bufs[i], ish_fw->data + offset, fragment->fragment_tbl[i].length);
	clflush_cache_range(dma_bufs[i], fragment_size);

	offset += fragment->fragment_tbl[i].length;
	}

	return 0;
	}

	/**
	* ishtp_loader_work() - Load the ISHTP firmware
	* @work: The work structure
	*
	* The ISH Loader attempts to load firmware by sending a series of commands
	* to the ISH device. If a command fails to be acknowledged by the ISH device,
	* the loader will retry sending the command, up to a maximum of
	* ISHTP_LOADER_RETRY_TIMES.
	*
	* After the maximum number of retries has been reached without success, the
	* ISH bootloader will return an error status code and will no longer respond
	* to the driver's commands. This behavior indicates that the ISH Loader has
	* encountered a critical error during the firmware loading process.
	*
	* In such a case, where the ISH bootloader is unresponsive after all retries
	* have been exhausted, a platform reset is required to restore communication
	* with the ISH device and to recover from this error state.
	*/
	void ishtp_loader_work(struct work_struct *work)
	{
	DEFINE_RAW_FLEX(struct loader_xfer_dma_fragment, fragment, fragment_tbl, FRAGMENT_MAX_NUM);
	struct ishtp_device *dev = container_of(work, struct ishtp_device, work_fw_loader);
	struct loader_xfer_query query = {
	.header.command = LOADER_CMD_XFER_QUERY,
	};
	struct loader_start start = {
	.header.command = LOADER_CMD_START,
	};
	union loader_recv_message recv_msg;
	char *filename = dev->driver_data->fw_filename;
	const struct firmware *ish_fw;
	void *dma_bufs[FRAGMENT_MAX_NUM] = {};
	u32 fragment_size;
	int retry = ISHTP_LOADER_RETRY_TIMES;
	int rv;

	rv = request_firmware(&ish_fw, filename, dev->devc);
	if (rv < 0) {
	dev_err(dev->devc, "request firmware %s failed:%d\n", filename, rv);
	return;
	}

	fragment->fragment.header.command = LOADER_CMD_XFER_FRAGMENT;
	fragment->fragment.xfer_mode = LOADER_XFER_MODE_DMA;
	fragment->fragment.is_last = 1;
	fragment->fragment.size = ish_fw->size;
	/* Calculate the size of a single DMA fragment */
	fragment_size = PFN_ALIGN(DIV_ROUND_UP(ish_fw->size, FRAGMENT_MAX_NUM));
	/* Calculate the count of DMA fragments */
	fragment->fragment_cnt = DIV_ROUND_UP(ish_fw->size, fragment_size);

	rv = prepare_dma_bufs(dev, ish_fw, fragment, dma_bufs, fragment_size);
	if (rv) {
	dev_err(dev->devc, "prepare DMA buffer failed.\n");
	goto out;
	}

	do {
	query.image_size = ish_fw->size;
	rv = loader_xfer_cmd(dev, &query, sizeof(query), recv_msg.raw_data,
	sizeof(struct loader_xfer_query_ack));
	if (rv)
	continue; /* try again if failed */

	dev_dbg(dev->devc, "ISH Version %u.%u.%u.%u\n",
	recv_msg.query_ack.version_major,
	recv_msg.query_ack.version_minor,
	recv_msg.query_ack.version_hotfix,
	recv_msg.query_ack.version_build);

	rv = loader_xfer_cmd(dev, fragment,
	struct_size(fragment, fragment_tbl, fragment->fragment_cnt),
	recv_msg.raw_data, sizeof(struct loader_xfer_fragment_ack));
	if (rv)
	continue; /* try again if failed */

	rv = loader_xfer_cmd(dev, &start, sizeof(start), recv_msg.raw_data,
	sizeof(struct loader_start_ack));
	if (rv)
	continue; /* try again if failed */

	dev_info(dev->devc, "firmware loaded. size:%zu\n", ish_fw->size);
	break;
	} while (--retry);

	out:
	release_dma_bufs(dev, fragment, dma_bufs, fragment_size);
	release_firmware(ish_fw);
	}