/*
*
* 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/pci.h>
#include <linux/sched.h>
#include <linux/wait.h>
#include <linux/delay.h>
#include <linux/mei.h>
#include "mei_dev.h"
#include "interface.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(RESETING);
MEI_DEV_STATE(DISABLED);
MEI_DEV_STATE(RECOVERING_FROM_RESET);
MEI_DEV_STATE(POWER_DOWN);
MEI_DEV_STATE(POWER_UP);
default:
return "unkown";
}
#undef MEI_DEV_STATE
}
/**
* init_mei_device - allocates and initializes the mei device structure
*
* @pdev: The pci device structure
*
* returns The mei_device_device pointer on success, NULL on failure.
*/
struct mei_device *mei_device_init(struct pci_dev *pdev)
{
struct mei_device *dev;
dev = kzalloc(sizeof(struct mei_device), GFP_KERNEL);
if (!dev)
return NULL;
/* setup our list array */
INIT_LIST_HEAD(&dev->file_list);
INIT_LIST_HEAD(&dev->wd_cl.link);
INIT_LIST_HEAD(&dev->iamthif_cl.link);
mutex_init(&dev->device_lock);
init_waitqueue_head(&dev->wait_recvd_msg);
init_waitqueue_head(&dev->wait_stop_wd);
dev->dev_state = MEI_DEV_INITIALIZING;
dev->iamthif_state = MEI_IAMTHIF_IDLE;
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);
mei_io_list_init(&dev->amthif_cmd_list);
mei_io_list_init(&dev->amthif_rd_complete_list);
dev->pdev = pdev;
return dev;
}
/**
* mei_hw_init - initializes host and fw to start work.
*
* @dev: the device structure
*
* returns 0 on success, <0 on failure.
*/
int mei_hw_init(struct mei_device *dev)
{
int err = 0;
int ret;
mutex_lock(&dev->device_lock);
dev->host_hw_state = mei_hcsr_read(dev);
dev->me_hw_state = mei_mecsr_read(dev);
dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, mestate = 0x%08x.\n",
dev->host_hw_state, dev->me_hw_state);
/* acknowledge interrupt and stop interupts */
mei_clear_interrupts(dev);
/* Doesn't change in runtime */
dev->hbuf_depth = (dev->host_hw_state & H_CBD) >> 24;
dev->recvd_msg = false;
dev_dbg(&dev->pdev->dev, "reset in start the mei device.\n");
mei_reset(dev, 1);
dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
dev->host_hw_state, dev->me_hw_state);
/* wait for ME to turn on ME_RDY */
if (!dev->recvd_msg) {
mutex_unlock(&dev->device_lock);
err = wait_event_interruptible_timeout(dev->wait_recvd_msg,
dev->recvd_msg,
mei_secs_to_jiffies(MEI_INTEROP_TIMEOUT));
mutex_lock(&dev->device_lock);
}
if (err <= 0 && !dev->recvd_msg) {
dev->dev_state = MEI_DEV_DISABLED;
dev_dbg(&dev->pdev->dev,
"wait_event_interruptible_timeout failed"
"on wait for ME to turn on ME_RDY.\n");
ret = -ENODEV;
goto out;
}
if (!(((dev->host_hw_state & H_RDY) == H_RDY) &&
((dev->me_hw_state & ME_RDY_HRA) == ME_RDY_HRA))) {
dev->dev_state = MEI_DEV_DISABLED;
dev_dbg(&dev->pdev->dev,
"host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
dev->host_hw_state, dev->me_hw_state);
if (!(dev->host_hw_state & H_RDY))
dev_dbg(&dev->pdev->dev, "host turn off H_RDY.\n");
if (!(dev->me_hw_state & ME_RDY_HRA))
dev_dbg(&dev->pdev->dev, "ME turn off ME_RDY.\n");
dev_err(&dev->pdev->dev, "link layer initialization failed.\n");
ret = -ENODEV;
goto out;
}
if (dev->version.major_version != HBM_MAJOR_VERSION ||
dev->version.minor_version != HBM_MINOR_VERSION) {
dev_dbg(&dev->pdev->dev, "MEI start failed.\n");
ret = -ENODEV;
goto out;
}
dev->recvd_msg = false;
dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
dev->host_hw_state, dev->me_hw_state);
dev_dbg(&dev->pdev->dev, "ME turn on ME_RDY and host turn on H_RDY.\n");
dev_dbg(&dev->pdev->dev, "link layer has been established.\n");
dev_dbg(&dev->pdev->dev, "MEI start success.\n");
ret = 0;
out:
mutex_unlock(&dev->device_lock);
return ret;
}
/**
* mei_hw_reset - resets fw via mei csr register.
*
* @dev: the device structure
* @interrupts_enabled: if interrupt should be enabled after reset.
*/
static void mei_hw_reset(struct mei_device *dev, int interrupts_enabled)
{
dev->host_hw_state |= (H_RST | H_IG);
if (interrupts_enabled)
mei_enable_interrupts(dev);
else
mei_disable_interrupts(dev);
}
/**
* mei_reset - resets host and fw.
*
* @dev: the device structure
* @interrupts_enabled: if interrupt should be enabled after reset.
*/
void mei_reset(struct mei_device *dev, int interrupts_enabled)
{
struct mei_cl *cl_pos = NULL;
struct mei_cl *cl_next = NULL;
struct mei_cl_cb *cb_pos = NULL;
struct mei_cl_cb *cb_next = NULL;
bool unexpected;
if (dev->dev_state == MEI_DEV_RECOVERING_FROM_RESET) {
dev->need_reset = true;
return;
}
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);
dev->host_hw_state = mei_hcsr_read(dev);
dev_dbg(&dev->pdev->dev, "before reset host_hw_state = 0x%08x.\n",
dev->host_hw_state);
mei_hw_reset(dev, interrupts_enabled);
dev->host_hw_state &= ~H_RST;
dev->host_hw_state |= H_IG;
mei_hcsr_set(dev);
dev_dbg(&dev->pdev->dev, "currently saved host_hw_state = 0x%08x.\n",
dev->host_hw_state);
dev->need_reset = false;
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_RESETING;
list_for_each_entry_safe(cl_pos,
cl_next, &dev->file_list, link) {
cl_pos->state = MEI_FILE_DISCONNECTED;
cl_pos->mei_flow_ctrl_creds = 0;
cl_pos->read_cb = NULL;
cl_pos->timer_count = 0;
}
/* remove entry if already in list */
dev_dbg(&dev->pdev->dev, "remove iamthif and wd from the file list.\n");
mei_me_cl_unlink(dev, &dev->wd_cl);
mei_me_cl_unlink(dev, &dev->iamthif_cl);
mei_amthif_reset_params(dev);
memset(&dev->wr_ext_msg, 0, sizeof(dev->wr_ext_msg));
}
dev->me_clients_num = 0;
dev->rd_msg_hdr = 0;
dev->wd_pending = false;
/* update the state of the registers after reset */
dev->host_hw_state = mei_hcsr_read(dev);
dev->me_hw_state = mei_mecsr_read(dev);
dev_dbg(&dev->pdev->dev, "after reset host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
dev->host_hw_state, dev->me_hw_state);
if (unexpected)
dev_warn(&dev->pdev->dev, "unexpected reset: dev_state = %s\n",
mei_dev_state_str(dev->dev_state));
/* Wake up all readings so they can be interrupted */
list_for_each_entry_safe(cl_pos, cl_next, &dev->file_list, link) {
if (waitqueue_active(&cl_pos->rx_wait)) {
dev_dbg(&dev->pdev->dev, "Waking up client!\n");
wake_up_interruptible(&cl_pos->rx_wait);
}
}
/* remove all waiting requests */
list_for_each_entry_safe(cb_pos, cb_next, &dev->write_list.list, list) {
list_del(&cb_pos->list);
mei_io_cb_free(cb_pos);
}
}
/**
* allocate_me_clients_storage - allocates storage for me clients
*
* @dev: the device structure
*
* returns none.
*/
void mei_allocate_me_clients_storage(struct mei_device *dev)
{
struct mei_me_client *clients;
int b;
/* count how many ME clients we have */
for_each_set_bit(b, dev->me_clients_map, MEI_CLIENTS_MAX)
dev->me_clients_num++;
if (dev->me_clients_num <= 0)
return ;
if (dev->me_clients != NULL) {
kfree(dev->me_clients);
dev->me_clients = NULL;
}
dev_dbg(&dev->pdev->dev, "memory allocation for ME clients size=%zd.\n",
dev->me_clients_num * sizeof(struct mei_me_client));
/* allocate storage for ME clients representation */
clients = kcalloc(dev->me_clients_num,
sizeof(struct mei_me_client), GFP_KERNEL);
if (!clients) {
dev_dbg(&dev->pdev->dev, "memory allocation for ME clients failed.\n");
dev->dev_state = MEI_DEV_RESETING;
mei_reset(dev, 1);
return ;
}
dev->me_clients = clients;
return ;
}
