drivers/misc/mei/pci-txe.c - linux - Git at Google

 // 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 = pci_set_dma_mask(pdev, DMA_BIT_MASK(36));
 	if (err) {
 		err = pci_set_dma_mask(pdev, 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_remove - 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;

 	dev = pci_get_drvdata(pdev);
 	if (!dev)
 		return;

 	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;

 	dev = pci_get_drvdata(pdev);
 	if (!dev) {
 		dev_err(&pdev->dev, "mei: dev == NULL\n");
 		return;
 	}

 	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);

 	if (!dev)
 		return -ENODEV;

 	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;
 	int err;

 	dev = pci_get_drvdata(pdev);
 	if (!dev)
 		return -ENODEV;

 	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_dbg(device, "rpm: txe: runtime_idle\n");

 	dev = dev_get_drvdata(device);
 	if (!dev)
 		return -ENODEV;
 	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;
 	int ret;

 	dev_dbg(device, "rpm: txe: runtime suspend\n");

 	dev = dev_get_drvdata(device);
 	if (!dev)
 		return -ENODEV;

 	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;
 	int ret;

 	dev_dbg(device, "rpm: txe: runtime resume\n");

 	dev = dev_get_drvdata(device);
 	if (!dev)
 		return -ENODEV;

 	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");
	// 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 = pci_set_dma_mask(pdev, DMA_BIT_MASK(36));
	if (err) {
	err = pci_set_dma_mask(pdev, 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_remove - 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;

	dev = pci_get_drvdata(pdev);
	if (!dev)
	return;

	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;

	dev = pci_get_drvdata(pdev);
	if (!dev) {
	dev_err(&pdev->dev, "mei: dev == NULL\n");
	return;
	}

	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);

	if (!dev)
	return -ENODEV;

	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;
	int err;

	dev = pci_get_drvdata(pdev);
	if (!dev)
	return -ENODEV;

	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_dbg(device, "rpm: txe: runtime_idle\n");

	dev = dev_get_drvdata(device);
	if (!dev)
	return -ENODEV;
	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;
	int ret;

	dev_dbg(device, "rpm: txe: runtime suspend\n");

	dev = dev_get_drvdata(device);
	if (!dev)
	return -ENODEV;

	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;
	int ret;

	dev_dbg(device, "rpm: txe: runtime resume\n");

	dev = dev_get_drvdata(device);
	if (!dev)
	return -ENODEV;

	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");