| /* |
| * |
| * 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 |
| } |
| |
| const char *mei_pg_state_str(enum mei_pg_state state) |
| { |
| #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_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) |
| { |
| const struct mei_fw_status *fw_src = &dev->cfg->fw_status; |
| int ret; |
| int i; |
| |
| if (!fw_status) |
| return -EINVAL; |
| |
| fw_status->count = fw_src->count; |
| for (i = 0; i < fw_src->count && i < MEI_FW_STATUS_MAX; i++) { |
| 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); |
| INIT_LIST_HEAD(&dev->me_clients); |
| mutex_init(&dev->device_lock); |
| init_waitqueue_head(&dev->wait_hw_ready); |
| init_waitqueue_head(&dev->wait_pg); |
| init_waitqueue_head(&dev->wait_hbm_start); |
| 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); |
| |