diff options
Diffstat (limited to 'drivers/misc/mei/wd.c')
| -rw-r--r-- | drivers/misc/mei/wd.c | 379 |
1 files changed, 379 insertions, 0 deletions
diff --git a/drivers/misc/mei/wd.c b/drivers/misc/mei/wd.c new file mode 100644 index 000000000000..6be5605707b4 --- /dev/null +++ b/drivers/misc/mei/wd.c @@ -0,0 +1,379 @@ +/* + * + * 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/kernel.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/device.h> +#include <linux/pci.h> +#include <linux/sched.h> +#include <linux/watchdog.h> + +#include "mei_dev.h" +#include "hw.h" +#include "interface.h" +#include <linux/mei.h> + +static const u8 mei_start_wd_params[] = { 0x02, 0x12, 0x13, 0x10 }; +static const u8 mei_stop_wd_params[] = { 0x02, 0x02, 0x14, 0x10 }; + +const u8 mei_wd_state_independence_msg[3][4] = { + {0x05, 0x02, 0x51, 0x10}, + {0x05, 0x02, 0x52, 0x10}, + {0x07, 0x02, 0x01, 0x10} +}; + +/* + * AMT Watchdog Device + */ +#define INTEL_AMT_WATCHDOG_ID "INTCAMT" + +/* UUIDs for AMT F/W clients */ +const uuid_le mei_wd_guid = UUID_LE(0x05B79A6F, 0x4628, 0x4D7F, 0x89, + 0x9D, 0xA9, 0x15, 0x14, 0xCB, + 0x32, 0xAB); + +static void mei_wd_set_start_timeout(struct mei_device *dev, u16 timeout) +{ + dev_dbg(&dev->pdev->dev, "wd: set timeout=%d.\n", timeout); + memcpy(dev->wd_data, mei_start_wd_params, MEI_WD_PARAMS_SIZE); + memcpy(dev->wd_data + MEI_WD_PARAMS_SIZE, &timeout, sizeof(u16)); +} + +/** + * host_init_wd - mei initialization wd. + * + * @dev: the device structure + * returns -ENENT if wd client cannot be found + * -EIO if write has failed + */ +int mei_wd_host_init(struct mei_device *dev) +{ + mei_cl_init(&dev->wd_cl, dev); + + /* look for WD client and connect to it */ + dev->wd_cl.state = MEI_FILE_DISCONNECTED; + dev->wd_timeout = AMT_WD_DEFAULT_TIMEOUT; + + /* find ME WD client */ + mei_find_me_client_update_filext(dev, &dev->wd_cl, + &mei_wd_guid, MEI_WD_HOST_CLIENT_ID); + + dev_dbg(&dev->pdev->dev, "wd: check client\n"); + if (MEI_FILE_CONNECTING != dev->wd_cl.state) { + dev_info(&dev->pdev->dev, "wd: failed to find the client\n"); + return -ENOENT; + } + + if (mei_connect(dev, &dev->wd_cl)) { + dev_err(&dev->pdev->dev, "wd: failed to connect to the client\n"); + dev->wd_cl.state = MEI_FILE_DISCONNECTED; + dev->wd_cl.host_client_id = 0; + return -EIO; + } + dev->wd_cl.timer_count = CONNECT_TIMEOUT; + + return 0; +} + +/** + * mei_wd_send - sends watch dog message to fw. + * + * @dev: the device structure + * + * returns 0 if success, + * -EIO when message send fails + * -EINVAL when invalid message is to be sent + */ +int mei_wd_send(struct mei_device *dev) +{ + struct mei_msg_hdr *mei_hdr; + + mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0]; + mei_hdr->host_addr = dev->wd_cl.host_client_id; + mei_hdr->me_addr = dev->wd_cl.me_client_id; + mei_hdr->msg_complete = 1; + mei_hdr->reserved = 0; + + if (!memcmp(dev->wd_data, mei_start_wd_params, MEI_WD_PARAMS_SIZE)) + mei_hdr->length = MEI_START_WD_DATA_SIZE; + else if (!memcmp(dev->wd_data, mei_stop_wd_params, MEI_WD_PARAMS_SIZE)) + mei_hdr->length = MEI_WD_PARAMS_SIZE; + else + return -EINVAL; + + return mei_write_message(dev, mei_hdr, dev->wd_data, mei_hdr->length); +} + +/** + * mei_wd_stop - sends watchdog stop message to fw. + * + * @dev: the device structure + * @preserve: indicate if to keep the timeout value + * + * returns 0 if success, + * -EIO when message send fails + * -EINVAL when invalid message is to be sent + */ +int mei_wd_stop(struct mei_device *dev, bool preserve) +{ + int ret; + u16 wd_timeout = dev->wd_timeout; + + cancel_delayed_work(&dev->timer_work); + if (dev->wd_cl.state != MEI_FILE_CONNECTED || !dev->wd_timeout) + return 0; + + dev->wd_timeout = 0; + dev->wd_due_counter = 0; + memcpy(dev->wd_data, mei_stop_wd_params, MEI_WD_PARAMS_SIZE); + dev->stop = true; + + ret = mei_flow_ctrl_creds(dev, &dev->wd_cl); + if (ret < 0) + goto out; + + if (ret && dev->mei_host_buffer_is_empty) { + ret = 0; + dev->mei_host_buffer_is_empty = false; + + if (!mei_wd_send(dev)) { + ret = mei_flow_ctrl_reduce(dev, &dev->wd_cl); + if (ret) + goto out; + } else { + dev_err(&dev->pdev->dev, "wd: send stop failed\n"); + } + + dev->wd_pending = false; + } else { + dev->wd_pending = true; + } + dev->wd_stopped = false; + mutex_unlock(&dev->device_lock); + + ret = wait_event_interruptible_timeout(dev->wait_stop_wd, + dev->wd_stopped, 10 * HZ); + mutex_lock(&dev->device_lock); + if (dev->wd_stopped) { + dev_dbg(&dev->pdev->dev, "wd: stop completed ret=%d.\n", ret); + ret = 0; + } else { + if (!ret) + ret = -ETIMEDOUT; + dev_warn(&dev->pdev->dev, + "wd: stop failed to complete ret=%d.\n", ret); + } + + if (preserve) + dev->wd_timeout = wd_timeout; + +out: + return ret; +} + +/* + * mei_wd_ops_start - wd start command from the watchdog core. + * + * @wd_dev - watchdog device struct + * + * returns 0 if success, negative errno code for failure + */ +static int mei_wd_ops_start(struct watchdog_device *wd_dev) +{ + int err = -ENODEV; + struct mei_device *dev; + + dev = pci_get_drvdata(mei_device); + if (!dev) + return -ENODEV; + + mutex_lock(&dev->device_lock); + + if (dev->mei_state != MEI_ENABLED) { + dev_dbg(&dev->pdev->dev, + "wd: mei_state != MEI_ENABLED mei_state = %d\n", + dev->mei_state); + goto end_unlock; + } + + if (dev->wd_cl.state != MEI_FILE_CONNECTED) { + dev_dbg(&dev->pdev->dev, + "MEI Driver is not connected to Watchdog Client\n"); + goto end_unlock; + } + + mei_wd_set_start_timeout(dev, dev->wd_timeout); + + err = 0; +end_unlock: + mutex_unlock(&dev->device_lock); + return err; +} + +/* + * mei_wd_ops_stop - wd stop command from the watchdog core. + * + * @wd_dev - watchdog device struct + * + * returns 0 if success, negative errno code for failure + */ +static int mei_wd_ops_stop(struct watchdog_device *wd_dev) +{ + struct mei_device *dev; + dev = pci_get_drvdata(mei_device); + + if (!dev) + return -ENODEV; + + mutex_lock(&dev->device_lock); + mei_wd_stop(dev, false); + mutex_unlock(&dev->device_lock); + + return 0; +} + +/* + * mei_wd_ops_ping - wd ping command from the watchdog core. + * + * @wd_dev - watchdog device struct + * + * returns 0 if success, negative errno code for failure + */ +static int mei_wd_ops_ping(struct watchdog_device *wd_dev) +{ + int ret = 0; + struct mei_device *dev; + dev = pci_get_drvdata(mei_device); + + if (!dev) + return -ENODEV; + + mutex_lock(&dev->device_lock); + + if (dev->wd_cl.state != MEI_FILE_CONNECTED) { + dev_err(&dev->pdev->dev, "wd: not connected.\n"); + ret = -ENODEV; + goto end; + } + + /* Check if we can send the ping to HW*/ + if (dev->mei_host_buffer_is_empty && + mei_flow_ctrl_creds(dev, &dev->wd_cl) > 0) { + + dev->mei_host_buffer_is_empty = false; + dev_dbg(&dev->pdev->dev, "wd: sending ping\n"); + + if (mei_wd_send(dev)) { + dev_err(&dev->pdev->dev, "wd: send failed.\n"); + ret = -EIO; + goto end; + } + + if (mei_flow_ctrl_reduce(dev, &dev->wd_cl)) { + dev_err(&dev->pdev->dev, + "wd: mei_flow_ctrl_reduce() failed.\n"); + ret = -EIO; + goto end; + } + + } else { + dev->wd_pending = true; + } + +end: + mutex_unlock(&dev->device_lock); + return ret; +} + +/* + * mei_wd_ops_set_timeout - wd set timeout command from the watchdog core. + * + * @wd_dev - watchdog device struct + * @timeout - timeout value to set + * + * returns 0 if success, negative errno code for failure + */ +static int mei_wd_ops_set_timeout(struct watchdog_device *wd_dev, unsigned int timeout) +{ + struct mei_device *dev; + dev = pci_get_drvdata(mei_device); + + if (!dev) + return -ENODEV; + + /* Check Timeout value */ + if (timeout < AMT_WD_MIN_TIMEOUT || timeout > AMT_WD_MAX_TIMEOUT) + return -EINVAL; + + mutex_lock(&dev->device_lock); + + dev->wd_timeout = timeout; + wd_dev->timeout = timeout; + mei_wd_set_start_timeout(dev, dev->wd_timeout); + + mutex_unlock(&dev->device_lock); + + return 0; +} + +/* + * Watchdog Device structs + */ +static const struct watchdog_ops wd_ops = { + .owner = THIS_MODULE, + .start = mei_wd_ops_start, + .stop = mei_wd_ops_stop, + .ping = mei_wd_ops_ping, + .set_timeout = mei_wd_ops_set_timeout, +}; +static const struct watchdog_info wd_info = { + .identity = INTEL_AMT_WATCHDOG_ID, + .options = WDIOF_KEEPALIVEPING, +}; + +static struct watchdog_device amt_wd_dev = { + .info = &wd_info, + .ops = &wd_ops, + .timeout = AMT_WD_DEFAULT_TIMEOUT, + .min_timeout = AMT_WD_MIN_TIMEOUT, + .max_timeout = AMT_WD_MAX_TIMEOUT, +}; + + +void mei_watchdog_register(struct mei_device *dev) +{ + dev_dbg(&dev->pdev->dev, "dev->wd_timeout =%d.\n", dev->wd_timeout); + + dev->wd_due_counter = !!dev->wd_timeout; + + if (watchdog_register_device(&amt_wd_dev)) { + dev_err(&dev->pdev->dev, + "wd: unable to register watchdog device.\n"); + dev->wd_interface_reg = false; + } else { + dev_dbg(&dev->pdev->dev, + "wd: successfully register watchdog interface.\n"); + dev->wd_interface_reg = true; + } +} + +void mei_watchdog_unregister(struct mei_device *dev) +{ + if (dev->wd_interface_reg) + watchdog_unregister_device(&amt_wd_dev); + dev->wd_interface_reg = false; +} + |