pci-txe.c
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2013-2020, Intel Corporation. All rights reserved.
* Intel Management Engine Interface (Intel MEI) Linux driver
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/workqueue.h>
#include <linux/pm_domain.h>
#include <linux/pm_runtime.h>
#include <linux/mei.h>
#include "mei_dev.h"
#include "hw-txe.h"
static const struct pci_device_id mei_txe_pci_tbl[] = {
{PCI_VDEVICE(INTEL, 0x0F18)}, /* Baytrail */
{PCI_VDEVICE(INTEL, 0x2298)}, /* Cherrytrail */
{0, }
};
MODULE_DEVICE_TABLE(pci, mei_txe_pci_tbl);
#ifdef CONFIG_PM
static inline void mei_txe_set_pm_domain(struct mei_device *dev);
static inline void mei_txe_unset_pm_domain(struct mei_device *dev);
#else
static inline void mei_txe_set_pm_domain(struct mei_device *dev) {}
static inline void mei_txe_unset_pm_domain(struct mei_device *dev) {}
#endif /* CONFIG_PM */
/**
* mei_txe_probe - Device Initialization Routine
*
* @pdev: PCI device structure
* @ent: entry in mei_txe_pci_tbl
*
* Return: 0 on success, <0 on failure.
*/
static int mei_txe_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
{
struct mei_device *dev;
struct mei_txe_hw *hw;
const int mask = BIT(SEC_BAR) | BIT(BRIDGE_BAR);
int err;
/* enable pci dev */
err = pcim_enable_device(pdev);
if (err) {
dev_err(&pdev->dev, "failed to enable pci device.\n");
goto end;
}
/* set PCI host mastering */
pci_set_master(pdev);
/* pci request regions and mapping IO device memory for mei driver */
err = pcim_iomap_regions(pdev, mask, KBUILD_MODNAME);
if (err) {
dev_err(&pdev->dev, "failed to get pci regions.\n");
goto end;
}
err = dma_set_mask(&pdev->dev, DMA_BIT_MASK(36));
if (err) {
err = dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));
if (err) {
dev_err(&pdev->dev, "No suitable DMA available.\n");
goto end;
}
}
/* allocates and initializes the mei dev structure */
dev = mei_txe_dev_init(pdev);
if (!dev) {
err = -ENOMEM;
goto end;
}
hw = to_txe_hw(dev);
hw->mem_addr = pcim_iomap_table(pdev);
pci_enable_msi(pdev);
/* clear spurious interrupts */
mei_clear_interrupts(dev);
/* request and enable interrupt */
if (pci_dev_msi_enabled(pdev))
err = request_threaded_irq(pdev->irq,
NULL,
mei_txe_irq_thread_handler,
IRQF_ONESHOT, KBUILD_MODNAME, dev);
else
err = request_threaded_irq(pdev->irq,
mei_txe_irq_quick_handler,
mei_txe_irq_thread_handler,
IRQF_SHARED, KBUILD_MODNAME, dev);
if (err) {
dev_err(&pdev->dev, "mei: request_threaded_irq failure. irq = %d\n",
pdev->irq);
goto end;
}
if (mei_start(dev)) {
dev_err(&pdev->dev, "init hw failure.\n");
err = -ENODEV;
goto release_irq;
}
pm_runtime_set_autosuspend_delay(&pdev->dev, MEI_TXI_RPM_TIMEOUT);
pm_runtime_use_autosuspend(&pdev->dev);
err = mei_register(dev, &pdev->dev);
if (err)
goto stop;
pci_set_drvdata(pdev, dev);
/*
* MEI requires to resume from runtime suspend mode
* in order to perform link reset flow upon system suspend.
*/
dev_pm_set_driver_flags(&pdev->dev, DPM_FLAG_NO_DIRECT_COMPLETE);
/*
* TXE maps runtime suspend/resume to own power gating states,
* hence we need to go around native PCI runtime service which
* eventually brings the device into D3cold/hot state.
* But the TXE device cannot wake up from D3 unlike from own
* power gating. To get around PCI device native runtime pm,
* TXE uses runtime pm domain handlers which take precedence.
*/
mei_txe_set_pm_domain(dev);
pm_runtime_put_noidle(&pdev->dev);
return 0;
stop:
mei_stop(dev);
release_irq:
mei_cancel_work(dev);
mei_disable_interrupts(dev);
free_irq(pdev->irq, dev);
end:
dev_err(&pdev->dev, "initialization failed.\n");
return err;
}
/**
* mei_txe_shutdown- Device Shutdown Routine
*
* @pdev: PCI device structure
*
* mei_txe_shutdown is called from the reboot notifier
* it's a simplified version of remove so we go down
* faster.
*/
static void mei_txe_shutdown(struct pci_dev *pdev)
{
struct mei_device *dev = pci_get_drvdata(pdev);
dev_dbg(&pdev->dev, "shutdown\n");
mei_stop(dev);
mei_txe_unset_pm_domain(dev);
mei_disable_interrupts(dev);
free_irq(pdev->irq, dev);
}
/**
* mei_txe_remove - Device Removal Routine
*
* @pdev: PCI device structure
*
* mei_remove is called by the PCI subsystem to alert the driver
* that it should release a PCI device.
*/
static void mei_txe_remove(struct pci_dev *pdev)
{
struct mei_device *dev = pci_get_drvdata(pdev);
pm_runtime_get_noresume(&pdev->dev);
mei_stop(dev);
mei_txe_unset_pm_domain(dev);
mei_disable_interrupts(dev);
free_irq(pdev->irq, dev);
mei_deregister(dev);
}
#ifdef CONFIG_PM_SLEEP
static int mei_txe_pci_suspend(struct device *device)
{
struct pci_dev *pdev = to_pci_dev(device);
struct mei_device *dev = pci_get_drvdata(pdev);
dev_dbg(&pdev->dev, "suspend\n");
mei_stop(dev);
mei_disable_interrupts(dev);
free_irq(pdev->irq, dev);
pci_disable_msi(pdev);
return 0;
}
static int mei_txe_pci_resume(struct device *device)
{
struct pci_dev *pdev = to_pci_dev(device);
struct mei_device *dev = pci_get_drvdata(pdev);
int err;
pci_enable_msi(pdev);
mei_clear_interrupts(dev);
/* request and enable interrupt */
if (pci_dev_msi_enabled(pdev))
err = request_threaded_irq(pdev->irq,
NULL,
mei_txe_irq_thread_handler,
IRQF_ONESHOT, KBUILD_MODNAME, dev);
else
err = request_threaded_irq(pdev->irq,
mei_txe_irq_quick_handler,
mei_txe_irq_thread_handler,
IRQF_SHARED, KBUILD_MODNAME, dev);
if (err) {
dev_err(&pdev->dev, "request_threaded_irq failed: irq = %d.\n",
pdev->irq);
return err;
}
err = mei_restart(dev);
return err;
}
#endif /* CONFIG_PM_SLEEP */
#ifdef CONFIG_PM
static int mei_txe_pm_runtime_idle(struct device *device)
{
struct mei_device *dev = dev_get_drvdata(device);
dev_dbg(device, "rpm: txe: runtime_idle\n");
if (mei_write_is_idle(dev))
pm_runtime_autosuspend(device);
return -EBUSY;
}
static int mei_txe_pm_runtime_suspend(struct device *device)
{
struct mei_device *dev = dev_get_drvdata(device);
int ret;
dev_dbg(device, "rpm: txe: runtime suspend\n");
mutex_lock(&dev->device_lock);
if (mei_write_is_idle(dev))
ret = mei_txe_aliveness_set_sync(dev, 0);
else
ret = -EAGAIN;
/* keep irq on we are staying in D0 */
dev_dbg(device, "rpm: txe: runtime suspend ret=%d\n", ret);
mutex_unlock(&dev->device_lock);
if (ret && ret != -EAGAIN)
schedule_work(&dev->reset_work);
return ret;
}
static int mei_txe_pm_runtime_resume(struct device *device)
{
struct mei_device *dev = dev_get_drvdata(device);
int ret;
dev_dbg(device, "rpm: txe: runtime resume\n");
mutex_lock(&dev->device_lock);
mei_enable_interrupts(dev);
ret = mei_txe_aliveness_set_sync(dev, 1);
mutex_unlock(&dev->device_lock);
dev_dbg(device, "rpm: txe: runtime resume ret = %d\n", ret);
if (ret)
schedule_work(&dev->reset_work);
return ret;
}
/**
* mei_txe_set_pm_domain - fill and set pm domain structure for device
*
* @dev: mei_device
*/
static inline void mei_txe_set_pm_domain(struct mei_device *dev)
{
struct pci_dev *pdev = to_pci_dev(dev->dev);
if (pdev->dev.bus && pdev->dev.bus->pm) {
dev->pg_domain.ops = *pdev->dev.bus->pm;
dev->pg_domain.ops.runtime_suspend = mei_txe_pm_runtime_suspend;
dev->pg_domain.ops.runtime_resume = mei_txe_pm_runtime_resume;
dev->pg_domain.ops.runtime_idle = mei_txe_pm_runtime_idle;
dev_pm_domain_set(&pdev->dev, &dev->pg_domain);
}
}
/**
* mei_txe_unset_pm_domain - clean pm domain structure for device
*
* @dev: mei_device
*/
static inline void mei_txe_unset_pm_domain(struct mei_device *dev)
{
/* stop using pm callbacks if any */
dev_pm_domain_set(dev->dev, NULL);
}
static const struct dev_pm_ops mei_txe_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(mei_txe_pci_suspend,
mei_txe_pci_resume)
SET_RUNTIME_PM_OPS(
mei_txe_pm_runtime_suspend,
mei_txe_pm_runtime_resume,
mei_txe_pm_runtime_idle)
};
#define MEI_TXE_PM_OPS (&mei_txe_pm_ops)
#else
#define MEI_TXE_PM_OPS NULL
#endif /* CONFIG_PM */
/*
* PCI driver structure
*/
static struct pci_driver mei_txe_driver = {
.name = KBUILD_MODNAME,
.id_table = mei_txe_pci_tbl,
.probe = mei_txe_probe,
.remove = mei_txe_remove,
.shutdown = mei_txe_shutdown,
.driver.pm = MEI_TXE_PM_OPS,
};
module_pci_driver(mei_txe_driver);
MODULE_AUTHOR("Intel Corporation");
MODULE_DESCRIPTION("Intel(R) Trusted Execution Environment Interface");
MODULE_LICENSE("GPL v2");