1 files changed, 323 insertions, 122 deletions

diff --git a/drivers/misc/mei/init.c b/drivers/misc/mei/init.c
index ed1d75203af6..b789c4d9c709 100644
--- a/drivers/misc/mei/init.c
+++ b/drivers/misc/mei/init.c
@@ -1,21 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
- *
+ * Copyright (c) 2012-2022, Intel Corporation. All rights reserved.
  * Intel Management Engine Interface (Intel MEI) Linux driver
- * Copyright (c) 2003-2012, Intel Corporation.
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms and conditions of the GNU General Public License,
- * version 2, as published by the Free Software Foundation.
- *
- * This program is distributed in the hope it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
- * more details.
- *
  */
 
 #include <linux/export.h>
-#include <linux/pci.h>
 #include <linux/sched.h>
 #include <linux/wait.h>
 #include <linux/delay.h>
@@ -35,6 +24,7 @@ const char *mei_dev_state_str(int state)
 	MEI_DEV_STATE(ENABLED);
 	MEI_DEV_STATE(RESETTING);
 	MEI_DEV_STATE(DISABLED);
+	MEI_DEV_STATE(POWERING_DOWN);
 	MEI_DEV_STATE(POWER_DOWN);
 	MEI_DEV_STATE(POWER_UP);
 	default:
@@ -43,188 +33,399 @@ const char *mei_dev_state_str(int state)
 #undef MEI_DEV_STATE
 }
 
-void mei_device_init(struct mei_device *dev)
+const char *mei_pg_state_str(enum mei_pg_state state)
 {
-	/* setup our list array */
-	INIT_LIST_HEAD(&dev->file_list);
-	INIT_LIST_HEAD(&dev->device_list);
-	mutex_init(&dev->device_lock);
-	init_waitqueue_head(&dev->wait_hw_ready);
-	init_waitqueue_head(&dev->wait_recvd_msg);
-	init_waitqueue_head(&dev->wait_stop_wd);
-	dev->dev_state = MEI_DEV_INITIALIZING;
+#define MEI_PG_STATE(state) case MEI_PG_##state: return #state
+	switch (state) {
+	MEI_PG_STATE(OFF);
+	MEI_PG_STATE(ON);
+	default:
+		return "unknown";
+	}
+#undef MEI_PG_STATE
+}
+
+/**
+ * mei_fw_status2str - convert fw status registers to printable string
+ *
+ * @fw_status:  firmware status
+ * @buf: string buffer at minimal size MEI_FW_STATUS_STR_SZ
+ * @len: buffer len must be >= MEI_FW_STATUS_STR_SZ
+ *
+ * Return: number of bytes written or -EINVAL if buffer is to small
+ */
+ssize_t mei_fw_status2str(struct mei_fw_status *fw_status,
+			  char *buf, size_t len)
+{
+	ssize_t cnt = 0;
+	int i;
 
-	mei_io_list_init(&dev->read_list);
-	mei_io_list_init(&dev->write_list);
-	mei_io_list_init(&dev->write_waiting_list);
-	mei_io_list_init(&dev->ctrl_wr_list);
-	mei_io_list_init(&dev->ctrl_rd_list);
+	buf[0] = '\0';
 
-	INIT_DELAYED_WORK(&dev->timer_work, mei_timer);
-	INIT_WORK(&dev->init_work, mei_host_client_init);
+	if (len < MEI_FW_STATUS_STR_SZ)
+		return -EINVAL;
 
-	INIT_LIST_HEAD(&dev->wd_cl.link);
-	INIT_LIST_HEAD(&dev->iamthif_cl.link);
-	mei_io_list_init(&dev->amthif_cmd_list);
-	mei_io_list_init(&dev->amthif_rd_complete_list);
+	for (i = 0; i < fw_status->count; i++)
+		cnt += scnprintf(buf + cnt, len - cnt, "%08X ",
+				fw_status->status[i]);
 
+	/* drop last space */
+	buf[cnt] = '\0';
+	return cnt;
 }
-EXPORT_SYMBOL_GPL(mei_device_init);
+EXPORT_SYMBOL_GPL(mei_fw_status2str);
 
 /**
- * mei_start - initializes host and fw to start work.
+ * mei_cancel_work - Cancel mei background jobs
  *
  * @dev: the device structure
+ */
+void mei_cancel_work(struct mei_device *dev)
+{
+	cancel_work_sync(&dev->reset_work);
+	cancel_work_sync(&dev->bus_rescan_work);
+
+	cancel_delayed_work_sync(&dev->timer_work);
+}
+EXPORT_SYMBOL_GPL(mei_cancel_work);
+
+/**
+ * mei_reset - resets host and fw.
  *
- * returns 0 on success, <0 on failure.
+ * @dev: the device structure
+ *
+ * Return: 0 on success or < 0 if the reset hasn't succeeded
  */
-int mei_start(struct mei_device *dev)
+int mei_reset(struct mei_device *dev)
 {
-	mutex_lock(&dev->device_lock);
+	enum mei_dev_state state = dev->dev_state;
+	bool interrupts_enabled;
+	int ret;
+
+	if (state != MEI_DEV_INITIALIZING &&
+	    state != MEI_DEV_DISABLED &&
+	    state != MEI_DEV_POWER_DOWN &&
+	    state != MEI_DEV_POWER_UP) {
+		char fw_sts_str[MEI_FW_STATUS_STR_SZ];
+
+		mei_fw_status_str(dev, fw_sts_str, MEI_FW_STATUS_STR_SZ);
+		if (kind_is_gsc(dev) || kind_is_gscfi(dev)) {
+			dev_dbg(&dev->dev, "unexpected reset: dev_state = %s fw status = %s\n",
+				mei_dev_state_str(state), fw_sts_str);
+		} else {
+			dev_warn(&dev->dev, "unexpected reset: dev_state = %s fw status = %s\n",
+				 mei_dev_state_str(state), fw_sts_str);
+		}
+	}
 
-	/* acknowledge interrupt and stop interupts */
 	mei_clear_interrupts(dev);
 
-	mei_hw_config(dev);
+	/* we're already in reset, cancel the init timer
+	 * if the reset was called due the hbm protocol error
+	 * we need to call it before hw start
+	 * so the hbm watchdog won't kick in
+	 */
+	mei_hbm_idle(dev);
+
+	/* enter reset flow */
+	interrupts_enabled = state != MEI_DEV_POWER_DOWN;
+	mei_set_devstate(dev, MEI_DEV_RESETTING);
+
+	dev->reset_count++;
+	if (dev->reset_count > MEI_MAX_CONSEC_RESET) {
+		dev_err(&dev->dev, "reset: reached maximal consecutive resets: disabling the device\n");
+		mei_set_devstate(dev, MEI_DEV_DISABLED);
+		return -ENODEV;
+	}
 
-	dev_dbg(&dev->pdev->dev, "reset in start the mei device.\n");
+	ret = mei_hw_reset(dev, interrupts_enabled);
+	/* fall through and remove the sw state even if hw reset has failed */
 
-	mei_reset(dev, 1);
+	/* no need to clean up software state in case of power up */
+	if (state != MEI_DEV_INITIALIZING && state != MEI_DEV_POWER_UP)
+		mei_cl_all_disconnect(dev);
 
-	if (mei_hbm_start_wait(dev)) {
-		dev_err(&dev->pdev->dev, "HBM haven't started");
-		goto err;
+	mei_hbm_reset(dev);
+
+	/* clean stale FW version */
+	dev->fw_ver_received = 0;
+
+	memset(dev->rd_msg_hdr, 0, sizeof(dev->rd_msg_hdr));
+
+	if (ret) {
+		dev_err(&dev->dev, "hw_reset failed ret = %d\n", ret);
+		return ret;
 	}
 
-	if (!mei_host_is_ready(dev)) {
-		dev_err(&dev->pdev->dev, "host is not ready.\n");
-		goto err;
+	if (state == MEI_DEV_POWER_DOWN) {
+		dev_dbg(&dev->dev, "powering down: end of reset\n");
+		mei_set_devstate(dev, MEI_DEV_DISABLED);
+		return 0;
+	}
+
+	ret = mei_hw_start(dev);
+	if (ret) {
+		char fw_sts_str[MEI_FW_STATUS_STR_SZ];
+
+		mei_fw_status_str(dev, fw_sts_str, MEI_FW_STATUS_STR_SZ);
+		dev_err(&dev->dev, "hw_start failed ret = %d fw status = %s\n", ret, fw_sts_str);
+		return ret;
+	}
+
+	if (dev->dev_state != MEI_DEV_RESETTING) {
+		dev_dbg(&dev->dev, "wrong state = %d on link start\n", dev->dev_state);
+		return 0;
 	}
 
-	if (!mei_hw_is_ready(dev)) {
-		dev_err(&dev->pdev->dev, "ME is not ready.\n");
+	dev_dbg(&dev->dev, "link is established start sending messages.\n");
+
+	mei_set_devstate(dev, MEI_DEV_INIT_CLIENTS);
+	ret = mei_hbm_start_req(dev);
+	if (ret) {
+		dev_err(&dev->dev, "hbm_start failed ret = %d\n", ret);
+		mei_set_devstate(dev, MEI_DEV_RESETTING);
+		return ret;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(mei_reset);
+
+/**
+ * mei_start - initializes host and fw to start work.
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+int mei_start(struct mei_device *dev)
+{
+	int ret;
+
+	mutex_lock(&dev->device_lock);
+
+	/* acknowledge interrupt and stop interrupts */
+	mei_clear_interrupts(dev);
+
+	ret = mei_hw_config(dev);
+	if (ret)
+		goto err;
+
+	dev_dbg(&dev->dev, "reset in start the mei device.\n");
+
+	dev->reset_count = 0;
+	do {
+		mei_set_devstate(dev, MEI_DEV_INITIALIZING);
+		ret = mei_reset(dev);
+
+		if (ret == -ENODEV || dev->dev_state == MEI_DEV_DISABLED) {
+			dev_err(&dev->dev, "reset failed ret = %d", ret);
+			goto err;
+		}
+	} while (ret);
+
+	if (mei_hbm_start_wait(dev)) {
+		dev_err(&dev->dev, "HBM haven't started");
 		goto err;
 	}
 
 	if (!mei_hbm_version_is_supported(dev)) {
-		dev_dbg(&dev->pdev->dev, "MEI start failed.\n");
+		dev_dbg(&dev->dev, "MEI start failed.\n");
 		goto err;
 	}
 
-	dev_dbg(&dev->pdev->dev, "link layer has been established.\n");
+	dev_dbg(&dev->dev, "link layer has been established.\n");
 
 	mutex_unlock(&dev->device_lock);
 	return 0;
 err:
-	dev_err(&dev->pdev->dev, "link layer initialization failed.\n");
-	dev->dev_state = MEI_DEV_DISABLED;
+	dev_err(&dev->dev, "link layer initialization failed.\n");
+	mei_set_devstate(dev, MEI_DEV_DISABLED);
 	mutex_unlock(&dev->device_lock);
 	return -ENODEV;
 }
 EXPORT_SYMBOL_GPL(mei_start);
 
 /**
- * mei_reset - resets host and fw.
+ * mei_restart - restart device after suspend
  *
  * @dev: the device structure
- * @interrupts_enabled: if interrupt should be enabled after reset.
+ *
+ * Return: 0 on success or -ENODEV if the restart hasn't succeeded
  */
-void mei_reset(struct mei_device *dev, int interrupts_enabled)
+int mei_restart(struct mei_device *dev)
 {
-	bool unexpected;
-	int ret;
+	int err;
 
-	unexpected = (dev->dev_state != MEI_DEV_INITIALIZING &&
-			dev->dev_state != MEI_DEV_DISABLED &&
-			dev->dev_state != MEI_DEV_POWER_DOWN &&
-			dev->dev_state != MEI_DEV_POWER_UP);
-
-	ret = mei_hw_reset(dev, interrupts_enabled);
-	if (ret) {
-		dev_err(&dev->pdev->dev, "hw reset failed disabling the device\n");
-		interrupts_enabled = false;
-		dev->dev_state = MEI_DEV_DISABLED;
-	}
+	mutex_lock(&dev->device_lock);
 
-	dev->hbm_state = MEI_HBM_IDLE;
+	mei_set_devstate(dev, MEI_DEV_POWER_UP);
+	dev->reset_count = 0;
 
-	if (dev->dev_state != MEI_DEV_INITIALIZING) {
-		if (dev->dev_state != MEI_DEV_DISABLED &&
-		    dev->dev_state != MEI_DEV_POWER_DOWN)
-			dev->dev_state = MEI_DEV_RESETTING;
+	err = mei_reset(dev);
 
-		mei_cl_all_disconnect(dev);
+	mutex_unlock(&dev->device_lock);
 
-		/* remove entry if already in list */
-		dev_dbg(&dev->pdev->dev, "remove iamthif and wd from the file list.\n");
-		mei_cl_unlink(&dev->wd_cl);
-		if (dev->open_handle_count > 0)
-			dev->open_handle_count--;
-		mei_cl_unlink(&dev->iamthif_cl);
-		if (dev->open_handle_count > 0)
-			dev->open_handle_count--;
-
-		mei_amthif_reset_params(dev);
-		memset(&dev->wr_ext_msg, 0, sizeof(dev->wr_ext_msg));
+	if (err == -ENODEV || dev->dev_state == MEI_DEV_DISABLED) {
+		dev_err(&dev->dev, "device disabled = %d\n", err);
+		return -ENODEV;
 	}
 
-	dev->me_clients_num = 0;
-	dev->rd_msg_hdr = 0;
-	dev->wd_pending = false;
+	/* try to start again */
+	if (err)
+		schedule_work(&dev->reset_work);
 
-	if (unexpected)
-		dev_warn(&dev->pdev->dev, "unexpected reset: dev_state = %s\n",
-			 mei_dev_state_str(dev->dev_state));
 
-	if (!interrupts_enabled) {
-		dev_dbg(&dev->pdev->dev, "intr not enabled end of reset\n");
-		return;
-	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(mei_restart);
 
-	ret = mei_hw_start(dev);
-	if (ret) {
-		dev_err(&dev->pdev->dev, "hw_start failed disabling the device\n");
-		dev->dev_state = MEI_DEV_DISABLED;
-		return;
-	}
+static void mei_reset_work(struct work_struct *work)
+{
+	struct mei_device *dev =
+		container_of(work, struct mei_device,  reset_work);
+	int ret;
 
-	dev_dbg(&dev->pdev->dev, "link is established start sending messages.\n");
-	/* link is established * start sending messages.  */
+	mei_clear_interrupts(dev);
+	mei_synchronize_irq(dev);
 
-	dev->dev_state = MEI_DEV_INIT_CLIENTS;
+	mutex_lock(&dev->device_lock);
 
-	mei_hbm_start_req(dev);
+	ret = mei_reset(dev);
 
-	/* wake up all readings so they can be interrupted */
-	mei_cl_all_read_wakeup(dev);
+	mutex_unlock(&dev->device_lock);
 
-	/* remove all waiting requests */
-	mei_cl_all_write_clear(dev);
+	if (dev->dev_state == MEI_DEV_DISABLED) {
+		dev_err(&dev->dev, "device disabled = %d\n", ret);
+		return;
+	}
+
+	/* retry reset in case of failure */
+	if (ret)
+		schedule_work(&dev->reset_work);
 }
-EXPORT_SYMBOL_GPL(mei_reset);
 
 void mei_stop(struct mei_device *dev)
 {
-	dev_dbg(&dev->pdev->dev, "stopping the device.\n");
-
-	flush_scheduled_work();
+	dev_dbg(&dev->dev, "stopping the device.\n");
 
 	mutex_lock(&dev->device_lock);
+	mei_set_devstate(dev, MEI_DEV_POWERING_DOWN);
+	mutex_unlock(&dev->device_lock);
+	mei_cl_bus_remove_devices(dev);
+	mutex_lock(&dev->device_lock);
+	mei_set_devstate(dev, MEI_DEV_POWER_DOWN);
+	mutex_unlock(&dev->device_lock);
 
-	cancel_delayed_work(&dev->timer_work);
+	mei_cancel_work(dev);
 
-	mei_wd_stop(dev);
+	mei_clear_interrupts(dev);
+	mei_synchronize_irq(dev);
+	/* to catch HW-initiated reset */
+	mei_cancel_work(dev);
 
-	mei_nfc_host_exit();
+	mutex_lock(&dev->device_lock);
 
-	dev->dev_state = MEI_DEV_POWER_DOWN;
-	mei_reset(dev, 0);
+	mei_reset(dev);
+	/* move device to disabled state unconditionally */
+	mei_set_devstate(dev, MEI_DEV_DISABLED);
 
 	mutex_unlock(&dev->device_lock);
-
-	mei_watchdog_unregister(dev);
 }
 EXPORT_SYMBOL_GPL(mei_stop);
 
+/**
+ * mei_write_is_idle - check if the write queues are idle
+ *
+ * @dev: the device structure
+ *
+ * Return: true of there is no pending write
+ */
+bool mei_write_is_idle(struct mei_device *dev)
+{
+	bool idle = (dev->dev_state == MEI_DEV_ENABLED &&
+		list_empty(&dev->ctrl_wr_list) &&
+		list_empty(&dev->write_list)   &&
+		list_empty(&dev->write_waiting_list));
+
+	dev_dbg(&dev->dev, "write pg: is idle[%d] state=%s ctrl=%01d write=%01d wwait=%01d\n",
+		idle,
+		mei_dev_state_str(dev->dev_state),
+		list_empty(&dev->ctrl_wr_list),
+		list_empty(&dev->write_list),
+		list_empty(&dev->write_waiting_list));
+
+	return idle;
+}
+EXPORT_SYMBOL_GPL(mei_write_is_idle);
 
+/**
+ * mei_device_init - initialize mei_device structure
+ *
+ * @dev: the mei device
+ * @parent: the parent device
+ * @slow_fw: configure longer timeouts as FW is slow
+ * @hw_ops: hw operations
+ */
+void mei_device_init(struct mei_device *dev,
+		     struct device *parent,
+		     bool slow_fw,
+		     const struct mei_hw_ops *hw_ops)
+{
+	/* setup our list array */
+	INIT_LIST_HEAD(&dev->file_list);
+	INIT_LIST_HEAD(&dev->device_list);
+	INIT_LIST_HEAD(&dev->me_clients);
+	mutex_init(&dev->device_lock);
+	init_rwsem(&dev->me_clients_rwsem);
+	mutex_init(&dev->cl_bus_lock);
+	init_waitqueue_head(&dev->wait_hw_ready);
+	init_waitqueue_head(&dev->wait_pg);
+	init_waitqueue_head(&dev->wait_hbm_start);
+	dev->dev_state = MEI_DEV_UNINITIALIZED;
+	init_waitqueue_head(&dev->wait_dev_state);
+	dev->reset_count = 0;
+
+	INIT_LIST_HEAD(&dev->write_list);
+	INIT_LIST_HEAD(&dev->write_waiting_list);
+	INIT_LIST_HEAD(&dev->ctrl_wr_list);
+	INIT_LIST_HEAD(&dev->ctrl_rd_list);
+	dev->tx_queue_limit = MEI_TX_QUEUE_LIMIT_DEFAULT;
 
+	INIT_DELAYED_WORK(&dev->timer_work, mei_timer);
+	INIT_WORK(&dev->reset_work, mei_reset_work);
+	INIT_WORK(&dev->bus_rescan_work, mei_cl_bus_rescan_work);
+
+	bitmap_zero(dev->host_clients_map, MEI_CLIENTS_MAX);
+	dev->open_handle_count = 0;
+
+	dev->pxp_mode = MEI_DEV_PXP_DEFAULT;
+	dev->gsc_reset_to_pxp = MEI_DEV_RESET_TO_PXP_DEFAULT;
+
+	/*
+	 * Reserving the first client ID
+	 * 0: Reserved for MEI Bus Message communications
+	 */
+	bitmap_set(dev->host_clients_map, 0, 1);
+
+	dev->pg_event = MEI_PG_EVENT_IDLE;
+	dev->ops      = hw_ops;
+	dev->parent   = parent;
+
+	dev->timeouts.hw_ready = mei_secs_to_jiffies(MEI_HW_READY_TIMEOUT);
+	dev->timeouts.connect = MEI_CONNECT_TIMEOUT;
+	dev->timeouts.client_init = MEI_CLIENTS_INIT_TIMEOUT;
+	dev->timeouts.pgi = mei_secs_to_jiffies(MEI_PGI_TIMEOUT);
+	dev->timeouts.d0i3 = mei_secs_to_jiffies(MEI_D0I3_TIMEOUT);
+	if (slow_fw) {
+		dev->timeouts.cl_connect = mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT_SLOW);
+		dev->timeouts.hbm = mei_secs_to_jiffies(MEI_HBM_TIMEOUT_SLOW);
+		dev->timeouts.mkhi_recv = msecs_to_jiffies(MKHI_RCV_TIMEOUT_SLOW);
+	} else {
+		dev->timeouts.cl_connect = mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT);
+		dev->timeouts.hbm = mei_secs_to_jiffies(MEI_HBM_TIMEOUT);
+		dev->timeouts.mkhi_recv = msecs_to_jiffies(MKHI_RCV_TIMEOUT);
+	}
+	dev->timeouts.link_reset_wait = msecs_to_jiffies(MEI_LINK_RESET_WAIT_TIMEOUT_MSEC);
+}
+EXPORT_SYMBOL_GPL(mei_device_init);