diff options
Diffstat (limited to 'drivers/misc/mei/init.c')
| -rw-r--r-- | drivers/misc/mei/init.c | 395 | 
1 files changed, 395 insertions, 0 deletions
diff --git a/drivers/misc/mei/init.c b/drivers/misc/mei/init.c new file mode 100644 index 00000000000..00692922248 --- /dev/null +++ b/drivers/misc/mei/init.c @@ -0,0 +1,395 @@ +/* + * + * 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> + +#include <linux/mei.h> + +#include "mei_dev.h" +#include "hbm.h" +#include "client.h" + +const char *mei_dev_state_str(int state) +{ +#define MEI_DEV_STATE(state) case MEI_DEV_##state: return #state +	switch (state) { +	MEI_DEV_STATE(INITIALIZING); +	MEI_DEV_STATE(INIT_CLIENTS); +	MEI_DEV_STATE(ENABLED); +	MEI_DEV_STATE(RESETTING); +	MEI_DEV_STATE(DISABLED); +	MEI_DEV_STATE(POWER_DOWN); +	MEI_DEV_STATE(POWER_UP); +	default: +		return "unknown"; +	} +#undef MEI_DEV_STATE +} + + +/** + * mei_cancel_work. Cancel mei background jobs + * + * @dev: the device structure + * + * returns 0 on success or < 0 if the reset hasn't succeeded + */ +void mei_cancel_work(struct mei_device *dev) +{ +	cancel_work_sync(&dev->init_work); +	cancel_work_sync(&dev->reset_work); + +	cancel_delayed_work(&dev->timer_work); +} +EXPORT_SYMBOL_GPL(mei_cancel_work); + +/** + * mei_reset - resets host and fw. + * + * @dev: the device structure + */ +int mei_reset(struct mei_device *dev) +{ +	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) { +		struct mei_fw_status fw_status; +		mei_fw_status(dev, &fw_status); +		dev_warn(&dev->pdev->dev, +			"unexpected reset: dev_state = %s " FW_STS_FMT "\n", +			mei_dev_state_str(state), FW_STS_PRM(fw_status)); +	} + +	/* 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; +	dev->dev_state = MEI_DEV_RESETTING; + +	dev->reset_count++; +	if (dev->reset_count > MEI_MAX_CONSEC_RESET) { +		dev_err(&dev->pdev->dev, "reset: reached maximal consecutive resets: disabling the device\n"); +		dev->dev_state = MEI_DEV_DISABLED; +		return -ENODEV; +	} + +	ret = mei_hw_reset(dev, interrupts_enabled); +	/* fall through and remove the sw state even if hw reset has failed */ + +	/* no need to clean up software state in case of power up */ +	if (state != MEI_DEV_INITIALIZING && +	    state != MEI_DEV_POWER_UP) { + +		/* remove all waiting requests */ +		mei_cl_all_write_clear(dev); + +		mei_cl_all_disconnect(dev); + +		/* wake up all readers and writers so they can be interrupted */ +		mei_cl_all_wakeup(dev); + +		/* 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); +		mei_cl_unlink(&dev->iamthif_cl); +		mei_amthif_reset_params(dev); +	} + +	mei_hbm_reset(dev); + +	dev->rd_msg_hdr = 0; +	dev->wd_pending = false; + +	if (ret) { +		dev_err(&dev->pdev->dev, "hw_reset failed ret = %d\n", ret); +		return ret; +	} + +	if (state == MEI_DEV_POWER_DOWN) { +		dev_dbg(&dev->pdev->dev, "powering down: end of reset\n"); +		dev->dev_state = MEI_DEV_DISABLED; +		return 0; +	} + +	ret = mei_hw_start(dev); +	if (ret) { +		dev_err(&dev->pdev->dev, "hw_start failed ret = %d\n", ret); +		return ret; +	} + +	dev_dbg(&dev->pdev->dev, "link is established start sending messages.\n"); + +	dev->dev_state = MEI_DEV_INIT_CLIENTS; +	ret = mei_hbm_start_req(dev); +	if (ret) { +		dev_err(&dev->pdev->dev, "hbm_start failed ret = %d\n", ret); +		dev->dev_state = 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 + * + * returns 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); + +	mei_hw_config(dev); + +	dev_dbg(&dev->pdev->dev, "reset in start the mei device.\n"); + +	dev->reset_count = 0; +	do { +		dev->dev_state = MEI_DEV_INITIALIZING; +		ret = mei_reset(dev); + +		if (ret == -ENODEV || dev->dev_state == MEI_DEV_DISABLED) { +			dev_err(&dev->pdev->dev, "reset failed ret = %d", ret); +			goto err; +		} +	} while (ret); + +	/* we cannot start the device w/o hbm start message completed */ +	if (dev->dev_state == MEI_DEV_DISABLED) { +		dev_err(&dev->pdev->dev, "reset failed"); +		goto err; +	} + +	if (mei_hbm_start_wait(dev)) { +		dev_err(&dev->pdev->dev, "HBM haven't started"); +		goto err; +	} + +	if (!mei_host_is_ready(dev)) { +		dev_err(&dev->pdev->dev, "host is not ready.\n"); +		goto err; +	} + +	if (!mei_hw_is_ready(dev)) { +		dev_err(&dev->pdev->dev, "ME is not ready.\n"); +		goto err; +	} + +	if (!mei_hbm_version_is_supported(dev)) { +		dev_dbg(&dev->pdev->dev, "MEI start failed.\n"); +		goto err; +	} + +	dev_dbg(&dev->pdev->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; +	mutex_unlock(&dev->device_lock); +	return -ENODEV; +} +EXPORT_SYMBOL_GPL(mei_start); + +/** + * mei_restart - restart device after suspend + * + * @dev: the device structure + * + * returns 0 on success or -ENODEV if the restart hasn't succeeded + */ +int mei_restart(struct mei_device *dev) +{ +	int err; + +	mutex_lock(&dev->device_lock); + +	mei_clear_interrupts(dev); + +	dev->dev_state = MEI_DEV_POWER_UP; +	dev->reset_count = 0; + +	err = mei_reset(dev); + +	mutex_unlock(&dev->device_lock); + +	if (err == -ENODEV || dev->dev_state == MEI_DEV_DISABLED) { +		dev_err(&dev->pdev->dev, "device disabled = %d\n", err); +		return -ENODEV; +	} + +	/* try to start again */ +	if (err) +		schedule_work(&dev->reset_work); + + +	return 0; +} +EXPORT_SYMBOL_GPL(mei_restart); + +static void mei_reset_work(struct work_struct *work) +{ +	struct mei_device *dev = +		container_of(work, struct mei_device,  reset_work); +	int ret; + +	mutex_lock(&dev->device_lock); + +	ret = mei_reset(dev); + +	mutex_unlock(&dev->device_lock); + +	if (dev->dev_state == MEI_DEV_DISABLED) { +		dev_err(&dev->pdev->dev, "device disabled = %d\n", ret); +		return; +	} + +	/* retry reset in case of failure */ +	if (ret) +		schedule_work(&dev->reset_work); +} + +void mei_stop(struct mei_device *dev) +{ +	dev_dbg(&dev->pdev->dev, "stopping the device.\n"); + +	mei_cancel_work(dev); + +	mei_nfc_host_exit(dev); + +	mei_cl_bus_remove_devices(dev); + +	mutex_lock(&dev->device_lock); + +	mei_wd_stop(dev); + +	dev->dev_state = MEI_DEV_POWER_DOWN; +	mei_reset(dev); + +	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 + * + * returns 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) && +		list_empty(&dev->write_list.list)); + +	dev_dbg(&dev->pdev->dev, "write pg: is idle[%d] state=%s ctrl=%d write=%d\n", +		idle, +		mei_dev_state_str(dev->dev_state), +		list_empty(&dev->ctrl_wr_list.list), +		list_empty(&dev->write_list.list)); + +	return idle; +} +EXPORT_SYMBOL_GPL(mei_write_is_idle); + +int mei_fw_status(struct mei_device *dev, struct mei_fw_status *fw_status) +{ +	int i; +	const struct mei_fw_status *fw_src = &dev->cfg->fw_status; + +	if (!fw_status) +		return -EINVAL; + +	fw_status->count = fw_src->count; +	for (i = 0; i < fw_src->count && i < MEI_FW_STATUS_MAX; i++) { +		int ret; +		ret = pci_read_config_dword(dev->pdev, +			fw_src->status[i], &fw_status->status[i]); +		if (ret) +			return ret; +	} + +	return 0; +} +EXPORT_SYMBOL_GPL(mei_fw_status); + +void mei_device_init(struct mei_device *dev, const struct mei_cfg *cfg) +{ +	/* 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_pg); +	init_waitqueue_head(&dev->wait_recvd_msg); +	init_waitqueue_head(&dev->wait_stop_wd); +	dev->dev_state = MEI_DEV_INITIALIZING; +	dev->reset_count = 0; + +	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); + +	INIT_DELAYED_WORK(&dev->timer_work, mei_timer); +	INIT_WORK(&dev->init_work, mei_host_client_init); +	INIT_WORK(&dev->reset_work, mei_reset_work); + +	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); + +	bitmap_zero(dev->host_clients_map, MEI_CLIENTS_MAX); +	dev->open_handle_count = 0; + +	/* +	 * 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->cfg      = cfg; +} +EXPORT_SYMBOL_GPL(mei_device_init); +  | 
