/*
* Intel MIC Platform Software Stack (MPSS)
*
* Copyright(c) 2013 Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License, version 2, as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that 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.
*
* The full GNU General Public License is included in this distribution in
* the file called "COPYING".
*
* Intel MIC Host driver.
*
*/
#include <linux/delay.h>
#include <linux/firmware.h>
#include <linux/mic_common.h>
#include "../common/mic_device.h"
#include "mic_device.h"
#include "mic_smpt.h"
#include "mic_virtio.h"
/**
* mic_reset - Reset the MIC device.
* @mdev: pointer to mic_device instance
*/
static void mic_reset(struct mic_device *mdev)
{
int i;
#define MIC_RESET_TO (45)
mdev->ops->reset_fw_ready(mdev);
mdev->ops->reset(mdev);
for (i = 0; i < MIC_RESET_TO; i++) {
if (mdev->ops->is_fw_ready(mdev))
return;
/*
* Resets typically take 10s of seconds to complete.
* Since an MMIO read is required to check if the
* firmware is ready or not, a 1 second delay works nicely.
*/
msleep(1000);
}
mic_set_state(mdev, MIC_RESET_FAILED);
}
/* Initialize the MIC bootparams */
void mic_bootparam_init(struct mic_device *mdev)
{
struct mic_bootparam *bootparam = mdev->dp;
bootparam->magic = MIC_MAGIC;
bootparam->c2h_shutdown_db = mdev->shutdown_db;
bootparam->h2c_shutdown_db = -1;
bootparam->h2c_config_db = -1;
bootparam->shutdown_status = 0;
bootparam->shutdown_card = 0;
}
/**
* mic_start - Start the MIC.
* @mdev: pointer to mic_device instance
* @buf: buffer containing boot string including firmware/ramdisk path.
*
* This function prepares an MIC for boot and initiates boot.
* RETURNS: An appropriate -ERRNO error value on error, or zero for success.
*/
int mic_start(struct mic_device *mdev, const char *buf)
{
int rc;
mutex_lock(&mdev->mic_mutex);
retry:
if (MIC_OFFLINE != mdev->state) {
rc = -EINVAL;
goto unlock_ret;
}
if (!mdev->ops->is_fw_ready(mdev)) {
mic_reset(mdev);
/*
* The state will either be MIC_OFFLINE if the reset succeeded
* or MIC_RESET_FAILED if the firmware reset failed.
*/
goto retry;
}
rc = mdev->ops->load_mic_fw(mdev, buf);
if (rc)
goto unlock_ret;
mic_smpt_restore(mdev);
mic_intr_restore(mdev);
mdev->intr_ops->enable_interrupts(mdev);
mdev->ops->write_spad(mdev, MIC_DPLO_SPAD, mdev->dp_dma_addr);
mdev->ops->write_spad(mdev, MIC_DPHI_SPAD, mdev->dp_dma_addr >> 32);
mdev->ops->send_firmware_intr(mdev);
mic_set_state(mdev, MIC_ONLINE);
unlock_ret:
mutex_unlock(&mdev->mic_mutex);
return rc;
}
/**
* mic_stop - Prepare the MIC for reset and trigger reset.
* @mdev: pointer to mic_device instance
* @force: force a MIC to reset even if it is already offline.
*
* RETURNS: None.
*/
void mic_stop(struct mic_device *mdev, bool force)
{
mutex_lock(&mdev->mic_mutex);
if (MIC_OFFLINE != mdev->state || force) {
mic_virtio_reset_devices(mdev);
mic_bootparam_init(mdev);
mic_reset(mdev);
if (MIC_RESET_FAILED == mdev->state)
goto unlock;
mic_set_shutdown_status(mdev, MIC_NOP);
mic_set_state(mdev, MIC_OFFLINE);
}
unlock:
mutex_unlock(&mdev->mic_mutex);
}
/**
* mic_shutdown - Initiate MIC shutdown.
* @mdev: pointer to mic_device instance
*
* RETURNS: None.
*/
void mic_shutdown(struct mic_device *mdev)
{
struct mic_bootparam *bootparam = mdev->dp;
s8 db = bootparam->h2c_shutdown_db;
mutex_lock(&mdev->mic_mutex);
if (MIC_ONLINE == mdev->state && db != -1) {
bootparam->shutdown_card = 1;
mdev->ops->send_intr(mdev, db);
mic_set_state(mdev, MIC_SHUTTING_DOWN);
}
mutex_unlock(&mdev->mic_mutex);
}
/**
* mic_shutdown_work - Handle shutdown interrupt from MIC.
* @work: The work structure.
*
* This work is scheduled whenever the host has received a shutdown
* interrupt from the MIC.
*/
void mic_shutdown_work(struct work_struct *work)
{
struct mic_device *mdev = container_of(work, struct mic_device,
shutdown_work);
struct mic_bootparam *bootparam = mdev->dp;
mutex_lock(&mdev->mic_mutex);
mic_set_shutdown_status(mdev, bootparam->shutdown_status);
bootparam->shutdown_status = 0;
if (MIC_SHUTTING_DOWN != mdev->state)
mic_set_state(mdev, MIC_SHUTTING_DOWN);
mutex_unlock(&mdev->mic_mutex);
}
/**
* mic_reset_trigger_work - Trigger MIC reset.
* @work: The work structure.
*
* This work is scheduled whenever the host wants to reset the MIC.
*/
void mic_reset_trigger_work(struct work_struct *work)
{
struct mic_device *mdev = container_of(work, struct mic_device,
reset_trigger_work);
mic_stop(mdev, false);
}
