drivers/net/ethernet/meta/fbnic/fbnic_pci.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /* Copyright (c) Meta Platforms, Inc. and affiliates. */

 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/types.h>

 #include "fbnic.h"
 #include "fbnic_drvinfo.h"

 char fbnic_driver_name[] = DRV_NAME;

 MODULE_DESCRIPTION(DRV_SUMMARY);
 MODULE_LICENSE("GPL");

 static const struct fbnic_info fbnic_asic_info = {
 	.bar_mask = BIT(0) | BIT(4)
 };

 static const struct fbnic_info *fbnic_info_tbl[] = {
 	[fbnic_board_asic] = &fbnic_asic_info,
 };

 static const struct pci_device_id fbnic_pci_tbl[] = {
 	{ PCI_DEVICE_DATA(META, FBNIC_ASIC, fbnic_board_asic) },
 	/* Required last entry */
 	{0, }
 };
 MODULE_DEVICE_TABLE(pci, fbnic_pci_tbl);

 u32 fbnic_rd32(struct fbnic_dev *fbd, u32 reg)
 {
 	u32 __iomem *csr = READ_ONCE(fbd->uc_addr0);
 	u32 value;

 	if (!csr)
 		return ~0U;

 	value = readl(csr + reg);

 	/* If any bits are 0 value should be valid */
 	if (~value)
 		return value;

 	/* All 1's may be valid if ZEROs register still works */
 	if (reg != FBNIC_MASTER_SPARE_0 && ~readl(csr + FBNIC_MASTER_SPARE_0))
 		return value;

 	/* Hardware is giving us all 1's reads, assume it is gone */
 	WRITE_ONCE(fbd->uc_addr0, NULL);
 	WRITE_ONCE(fbd->uc_addr4, NULL);

 	dev_err(fbd->dev,
 		"Failed read (idx 0x%x AKA addr 0x%x), disabled CSR access, awaiting reset\n",
 		reg, reg << 2);

 	return ~0U;
 }

 /**
  * fbnic_probe - Device Initialization Routine
  * @pdev: PCI device information struct
  * @ent: entry in fbnic_pci_tbl
  *
  * Initializes a PCI device identified by a pci_dev structure.
  * The OS initialization, configuring of the adapter private structure,
  * and a hardware reset occur.
  *
  * Return: 0 on success, negative on failure
  **/
 static int fbnic_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 {
 	const struct fbnic_info *info = fbnic_info_tbl[ent->driver_data];
 	struct fbnic_dev *fbd;
 	int err;

 	if (pdev->error_state != pci_channel_io_normal) {
 		dev_err(&pdev->dev,
 			"PCI device still in an error state. Unable to load...\n");
 		return -EIO;
 	}

 	err = pcim_enable_device(pdev);
 	if (err) {
 		dev_err(&pdev->dev, "PCI enable device failed: %d\n", err);
 		return err;
 	}

 	err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(46));
 	if (err)
 		err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 	if (err) {
 		dev_err(&pdev->dev, "DMA configuration failed: %d\n", err);
 		return err;
 	}

 	err = pcim_iomap_regions(pdev, info->bar_mask, fbnic_driver_name);
 	if (err) {
 		dev_err(&pdev->dev,
 			"pci_request_selected_regions failed: %d\n", err);
 		return err;
 	}

 	fbd = fbnic_devlink_alloc(pdev);
 	if (!fbd) {
 		dev_err(&pdev->dev, "Devlink allocation failed\n");
 		return -ENOMEM;
 	}

 	pci_set_master(pdev);
 	pci_save_state(pdev);

 	err = fbnic_alloc_irqs(fbd);
 	if (err)
 		goto free_fbd;

 	err = fbnic_mac_init(fbd);
 	if (err) {
 		dev_err(&pdev->dev, "Failed to initialize MAC: %d\n", err);
 		goto free_irqs;
 	}

 	fbnic_devlink_register(fbd);

 	if (!fbd->dsn) {
 		dev_warn(&pdev->dev, "Reading serial number failed\n");
 		goto init_failure_mode;
 	}

 	return 0;

 init_failure_mode:
 	dev_warn(&pdev->dev, "Probe error encountered, entering init failure mode. Normal networking functionality will not be available.\n");
 	 /* Always return 0 even on error so devlink is registered to allow
 	  * firmware updates for fixes.
 	  */
 	return 0;
 free_irqs:
 	fbnic_free_irqs(fbd);
 free_fbd:
 	pci_disable_device(pdev);
 	fbnic_devlink_free(fbd);

 	return err;
 }

 /**
  * fbnic_remove - Device Removal Routine
  * @pdev: PCI device information struct
  *
  * Called by the PCI subsystem to alert the driver that it should release
  * a PCI device.  The could be caused by a Hot-Plug event, or because the
  * driver is going to be removed from memory.
  **/
 static void fbnic_remove(struct pci_dev *pdev)
 {
 	struct fbnic_dev *fbd = pci_get_drvdata(pdev);

 	fbnic_devlink_unregister(fbd);
 	fbnic_free_irqs(fbd);

 	pci_disable_device(pdev);
 	fbnic_devlink_free(fbd);
 }

 static int fbnic_pm_suspend(struct device *dev)
 {
 	struct fbnic_dev *fbd = dev_get_drvdata(dev);

 	/* Free the IRQs so they aren't trying to occupy sleeping CPUs */
 	fbnic_free_irqs(fbd);

 	/* Hardware is about to go away, so switch off MMIO access internally */
 	WRITE_ONCE(fbd->uc_addr0, NULL);
 	WRITE_ONCE(fbd->uc_addr4, NULL);

 	return 0;
 }

 static int __fbnic_pm_resume(struct device *dev)
 {
 	struct fbnic_dev *fbd = dev_get_drvdata(dev);
 	void __iomem * const *iomap_table;
 	int err;

 	/* Restore MMIO access */
 	iomap_table = pcim_iomap_table(to_pci_dev(dev));
 	fbd->uc_addr0 = iomap_table[0];
 	fbd->uc_addr4 = iomap_table[4];

 	/* Rerequest the IRQs */
 	err = fbnic_alloc_irqs(fbd);
 	if (err)
 		goto err_invalidate_uc_addr;

 	fbd->mac->init_regs(fbd);

 	return 0;
 err_invalidate_uc_addr:
 	WRITE_ONCE(fbd->uc_addr0, NULL);
 	WRITE_ONCE(fbd->uc_addr4, NULL);
 	return err;
 }

 static int __maybe_unused fbnic_pm_resume(struct device *dev)
 {
 	int err;

 	err = __fbnic_pm_resume(dev);

 	return err;
 }

 static const struct dev_pm_ops fbnic_pm_ops = {
 	SET_SYSTEM_SLEEP_PM_OPS(fbnic_pm_suspend, fbnic_pm_resume)
 };

 static void fbnic_shutdown(struct pci_dev *pdev)
 {
 	fbnic_pm_suspend(&pdev->dev);
 }

 static pci_ers_result_t fbnic_err_error_detected(struct pci_dev *pdev,
 						 pci_channel_state_t state)
 {
 	/* Disconnect device if failure is not recoverable via reset */
 	if (state == pci_channel_io_perm_failure)
 		return PCI_ERS_RESULT_DISCONNECT;

 	fbnic_pm_suspend(&pdev->dev);

 	/* Request a slot reset */
 	return PCI_ERS_RESULT_NEED_RESET;
 }

 static pci_ers_result_t fbnic_err_slot_reset(struct pci_dev *pdev)
 {
 	int err;

 	pci_set_power_state(pdev, PCI_D0);
 	pci_restore_state(pdev);
 	pci_save_state(pdev);

 	if (pci_enable_device_mem(pdev)) {
 		dev_err(&pdev->dev,
 			"Cannot re-enable PCI device after reset.\n");
 		return PCI_ERS_RESULT_DISCONNECT;
 	}

 	/* Restore device to previous state */
 	err = __fbnic_pm_resume(&pdev->dev);

 	return err ? PCI_ERS_RESULT_DISCONNECT : PCI_ERS_RESULT_RECOVERED;
 }

 static void fbnic_err_resume(struct pci_dev *pdev)
 {
 }

 static const struct pci_error_handlers fbnic_err_handler = {
 	.error_detected	= fbnic_err_error_detected,
 	.slot_reset	= fbnic_err_slot_reset,
 	.resume		= fbnic_err_resume,
 };

 static struct pci_driver fbnic_driver = {
 	.name		= fbnic_driver_name,
 	.id_table	= fbnic_pci_tbl,
 	.probe		= fbnic_probe,
 	.remove		= fbnic_remove,
 	.driver.pm	= &fbnic_pm_ops,
 	.shutdown	= fbnic_shutdown,
 	.err_handler	= &fbnic_err_handler,
 };

 /**
  * fbnic_init_module - Driver Registration Routine
  *
  * The first routine called when the driver is loaded.  All it does is
  * register with the PCI subsystem.
  *
  * Return: 0 on success, negative on failure
  **/
 static int __init fbnic_init_module(void)
 {
 	int err;

 	err = pci_register_driver(&fbnic_driver);
 	if (err)
 		goto out;

 	pr_info(DRV_SUMMARY " (%s)", fbnic_driver.name);
 out:
 	return err;
 }
 module_init(fbnic_init_module);

 /**
  * fbnic_exit_module - Driver Exit Cleanup Routine
  *
  * Called just before the driver is removed from memory.
  **/
 static void __exit fbnic_exit_module(void)
 {
 	pci_unregister_driver(&fbnic_driver);
 }
 module_exit(fbnic_exit_module);
	// SPDX-License-Identifier: GPL-2.0
	/* Copyright (c) Meta Platforms, Inc. and affiliates. */

	#include <linux/init.h>
	#include <linux/module.h>
	#include <linux/pci.h>
	#include <linux/types.h>

	#include "fbnic.h"
	#include "fbnic_drvinfo.h"

	char fbnic_driver_name[] = DRV_NAME;

	MODULE_DESCRIPTION(DRV_SUMMARY);
	MODULE_LICENSE("GPL");

	static const struct fbnic_info fbnic_asic_info = {
	.bar_mask = BIT(0) \| BIT(4)
	};

	static const struct fbnic_info *fbnic_info_tbl[] = {
	[fbnic_board_asic] = &fbnic_asic_info,
	};

	static const struct pci_device_id fbnic_pci_tbl[] = {
	{ PCI_DEVICE_DATA(META, FBNIC_ASIC, fbnic_board_asic) },
	/* Required last entry */
	{0, }
	};
	MODULE_DEVICE_TABLE(pci, fbnic_pci_tbl);

	u32 fbnic_rd32(struct fbnic_dev *fbd, u32 reg)
	{
	u32 __iomem *csr = READ_ONCE(fbd->uc_addr0);
	u32 value;

	if (!csr)
	return ~0U;

	value = readl(csr + reg);

	/* If any bits are 0 value should be valid */
	if (~value)
	return value;

	/* All 1's may be valid if ZEROs register still works */
	if (reg != FBNIC_MASTER_SPARE_0 && ~readl(csr + FBNIC_MASTER_SPARE_0))
	return value;

	/* Hardware is giving us all 1's reads, assume it is gone */
	WRITE_ONCE(fbd->uc_addr0, NULL);
	WRITE_ONCE(fbd->uc_addr4, NULL);

	dev_err(fbd->dev,
	"Failed read (idx 0x%x AKA addr 0x%x), disabled CSR access, awaiting reset\n",
	reg, reg << 2);

	return ~0U;
	}

	/**
	* fbnic_probe - Device Initialization Routine
	* @pdev: PCI device information struct
	* @ent: entry in fbnic_pci_tbl
	*
	* Initializes a PCI device identified by a pci_dev structure.
	* The OS initialization, configuring of the adapter private structure,
	* and a hardware reset occur.
	*
	* Return: 0 on success, negative on failure
	**/
	static int fbnic_probe(struct pci_dev pdev, const struct pci_device_id ent)
	{
	const struct fbnic_info *info = fbnic_info_tbl[ent->driver_data];
	struct fbnic_dev *fbd;
	int err;

	if (pdev->error_state != pci_channel_io_normal) {
	dev_err(&pdev->dev,
	"PCI device still in an error state. Unable to load...\n");
	return -EIO;
	}

	err = pcim_enable_device(pdev);
	if (err) {
	dev_err(&pdev->dev, "PCI enable device failed: %d\n", err);
	return err;
	}

	err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(46));
	if (err)
	err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
	if (err) {
	dev_err(&pdev->dev, "DMA configuration failed: %d\n", err);
	return err;
	}

	err = pcim_iomap_regions(pdev, info->bar_mask, fbnic_driver_name);
	if (err) {
	dev_err(&pdev->dev,
	"pci_request_selected_regions failed: %d\n", err);
	return err;
	}

	fbd = fbnic_devlink_alloc(pdev);
	if (!fbd) {
	dev_err(&pdev->dev, "Devlink allocation failed\n");
	return -ENOMEM;
	}

	pci_set_master(pdev);
	pci_save_state(pdev);

	err = fbnic_alloc_irqs(fbd);
	if (err)
	goto free_fbd;

	err = fbnic_mac_init(fbd);
	if (err) {
	dev_err(&pdev->dev, "Failed to initialize MAC: %d\n", err);
	goto free_irqs;
	}

	fbnic_devlink_register(fbd);

	if (!fbd->dsn) {
	dev_warn(&pdev->dev, "Reading serial number failed\n");
	goto init_failure_mode;
	}

	return 0;

	init_failure_mode:
	dev_warn(&pdev->dev, "Probe error encountered, entering init failure mode. Normal networking functionality will not be available.\n");
	/* Always return 0 even on error so devlink is registered to allow
	* firmware updates for fixes.
	*/
	return 0;
	free_irqs:
	fbnic_free_irqs(fbd);
	free_fbd:
	pci_disable_device(pdev);
	fbnic_devlink_free(fbd);

	return err;
	}

	/**
	* fbnic_remove - Device Removal Routine
	* @pdev: PCI device information struct
	*
	* Called by the PCI subsystem to alert the driver that it should release
	* a PCI device. The could be caused by a Hot-Plug event, or because the
	* driver is going to be removed from memory.
	**/
	static void fbnic_remove(struct pci_dev *pdev)
	{
	struct fbnic_dev *fbd = pci_get_drvdata(pdev);

	fbnic_devlink_unregister(fbd);
	fbnic_free_irqs(fbd);

	pci_disable_device(pdev);
	fbnic_devlink_free(fbd);
	}

	static int fbnic_pm_suspend(struct device *dev)
	{
	struct fbnic_dev *fbd = dev_get_drvdata(dev);

	/* Free the IRQs so they aren't trying to occupy sleeping CPUs */
	fbnic_free_irqs(fbd);

	/* Hardware is about to go away, so switch off MMIO access internally */
	WRITE_ONCE(fbd->uc_addr0, NULL);
	WRITE_ONCE(fbd->uc_addr4, NULL);

	return 0;
	}

	static int __fbnic_pm_resume(struct device *dev)
	{
	struct fbnic_dev *fbd = dev_get_drvdata(dev);
	void __iomem * const *iomap_table;
	int err;

	/* Restore MMIO access */
	iomap_table = pcim_iomap_table(to_pci_dev(dev));
	fbd->uc_addr0 = iomap_table[0];
	fbd->uc_addr4 = iomap_table[4];

	/* Rerequest the IRQs */
	err = fbnic_alloc_irqs(fbd);
	if (err)
	goto err_invalidate_uc_addr;

	fbd->mac->init_regs(fbd);

	return 0;
	err_invalidate_uc_addr:
	WRITE_ONCE(fbd->uc_addr0, NULL);
	WRITE_ONCE(fbd->uc_addr4, NULL);
	return err;
	}

	static int __maybe_unused fbnic_pm_resume(struct device *dev)
	{
	int err;

	err = __fbnic_pm_resume(dev);

	return err;
	}

	static const struct dev_pm_ops fbnic_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(fbnic_pm_suspend, fbnic_pm_resume)
	};

	static void fbnic_shutdown(struct pci_dev *pdev)
	{
	fbnic_pm_suspend(&pdev->dev);
	}

	static pci_ers_result_t fbnic_err_error_detected(struct pci_dev *pdev,
	pci_channel_state_t state)
	{
	/* Disconnect device if failure is not recoverable via reset */
	if (state == pci_channel_io_perm_failure)
	return PCI_ERS_RESULT_DISCONNECT;

	fbnic_pm_suspend(&pdev->dev);

	/* Request a slot reset */
	return PCI_ERS_RESULT_NEED_RESET;
	}

	static pci_ers_result_t fbnic_err_slot_reset(struct pci_dev *pdev)
	{
	int err;

	pci_set_power_state(pdev, PCI_D0);
	pci_restore_state(pdev);
	pci_save_state(pdev);

	if (pci_enable_device_mem(pdev)) {
	dev_err(&pdev->dev,
	"Cannot re-enable PCI device after reset.\n");
	return PCI_ERS_RESULT_DISCONNECT;
	}

	/* Restore device to previous state */
	err = __fbnic_pm_resume(&pdev->dev);

	return err ? PCI_ERS_RESULT_DISCONNECT : PCI_ERS_RESULT_RECOVERED;
	}

	static void fbnic_err_resume(struct pci_dev *pdev)
	{
	}

	static const struct pci_error_handlers fbnic_err_handler = {
	.error_detected = fbnic_err_error_detected,
	.slot_reset = fbnic_err_slot_reset,
	.resume = fbnic_err_resume,
	};

	static struct pci_driver fbnic_driver = {
	.name = fbnic_driver_name,
	.id_table = fbnic_pci_tbl,
	.probe = fbnic_probe,
	.remove = fbnic_remove,
	.driver.pm = &fbnic_pm_ops,
	.shutdown = fbnic_shutdown,
	.err_handler = &fbnic_err_handler,
	};

	/**
	* fbnic_init_module - Driver Registration Routine
	*
	* The first routine called when the driver is loaded. All it does is
	* register with the PCI subsystem.
	*
	* Return: 0 on success, negative on failure
	**/
	static int __init fbnic_init_module(void)
	{
	int err;

	err = pci_register_driver(&fbnic_driver);
	if (err)
	goto out;

	pr_info(DRV_SUMMARY " (%s)", fbnic_driver.name);
	out:
	return err;
	}
	module_init(fbnic_init_module);

	/**
	* fbnic_exit_module - Driver Exit Cleanup Routine
	*
	* Called just before the driver is removed from memory.
	**/
	static void __exit fbnic_exit_module(void)
	{
	pci_unregister_driver(&fbnic_driver);
	}
	module_exit(fbnic_exit_module);