Commit 56f107d7 authored by Amey Narkhede's avatar Amey Narkhede Committed by Bjorn Helgaas
Browse files

PCI: Add pcie_reset_flr() with 'probe' argument 

Most reset methods are of the form "pci_*_reset(dev, probe)".  pcie_flr()
was an exception because it relied on a separate pcie_has_flr() function
instead of taking a "probe" argument.

Add "pcie_reset_flr(dev, probe)" to follow the convention.  Remove
pcie_has_flr().

Some pcie_flr() callers that did not use pcie_has_flr() remain.

[bhelgaas: commit log, rework pcie_reset_flr() to use dev->devcap directly]
Link: https://lore.kernel.org/r/20210817180500.1253-3-ameynarkhede03@gmail.com


Signed-off-by: default avatarAmey Narkhede <ameynarkhede03@gmail.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: default avatarRaphael Norwitz <raphael.norwitz@nutanix.com>
parent 69139244

drivers/crypto/cavium/nitrox/nitrox_main.c

+1 −3
Original line number Diff line number Diff line
@@ -306,9 +306,7 @@ static int nitrox_device_flr(struct pci_dev *pdev) 
		return -ENOMEM;

	}



	/* check flr support */

	if (pcie_has_flr(pdev))

		pcie_flr(pdev);

	pcie_reset_flr(pdev, 0);



	pci_restore_state(pdev);

drivers/pci/pci.c

+30 −26
Original line number Diff line number Diff line
@@ -4622,29 +4622,12 @@ int pci_wait_for_pending_transaction(struct pci_dev *dev) 
}

EXPORT_SYMBOL(pci_wait_for_pending_transaction);



/**

 * pcie_has_flr - check if a device supports function level resets

 * @dev: device to check

 *

 * Returns true if the device advertises support for PCIe function level

 * resets.

 */

bool pcie_has_flr(struct pci_dev *dev)

{

	if (dev->dev_flags & PCI_DEV_FLAGS_NO_FLR_RESET)

		return false;



	return FIELD_GET(PCI_EXP_DEVCAP_FLR, dev->devcap) == 1;

}

EXPORT_SYMBOL_GPL(pcie_has_flr);



/**

 * pcie_flr - initiate a PCIe function level reset

 * @dev: device to reset

 *

 * Initiate a function level reset on @dev.  The caller should ensure the

 * device supports FLR before calling this function, e.g. by using the

 * pcie_has_flr() helper.

 * Initiate a function level reset unconditionally on @dev without

 * checking any flags and DEVCAP

 */

int pcie_flr(struct pci_dev *dev)

{
@@ -4667,6 +4650,28 @@ int pcie_flr(struct pci_dev *dev) 
}

EXPORT_SYMBOL_GPL(pcie_flr);



/**

 * pcie_reset_flr - initiate a PCIe function level reset

 * @dev: device to reset

 * @probe: If set, only check if the device can be reset this way.

 *

 * Initiate a function level reset on @dev.

 */

int pcie_reset_flr(struct pci_dev *dev, int probe)

{

	if (dev->dev_flags & PCI_DEV_FLAGS_NO_FLR_RESET)

		return -ENOTTY;



	if (!(dev->devcap & PCI_EXP_DEVCAP_FLR))

		return -ENOTTY;



	if (probe)

		return 0;



	return pcie_flr(dev);

}

EXPORT_SYMBOL_GPL(pcie_reset_flr);



static int pci_af_flr(struct pci_dev *dev, int probe)

{

	int pos;
@@ -5149,11 +5154,9 @@ int __pci_reset_function_locked(struct pci_dev *dev) 
	rc = pci_dev_specific_reset(dev, 0);

	if (rc != -ENOTTY)

		return rc;

	if (pcie_has_flr(dev)) {

		rc = pcie_flr(dev);

	rc = pcie_reset_flr(dev, 0);

	if (rc != -ENOTTY)

		return rc;

	}

	rc = pci_af_flr(dev, 0);

	if (rc != -ENOTTY)

		return rc;
@@ -5184,8 +5187,9 @@ int pci_probe_reset_function(struct pci_dev *dev) 
	rc = pci_dev_specific_reset(dev, 1);

	if (rc != -ENOTTY)

		return rc;

	if (pcie_has_flr(dev))

		return 0;

	rc = pcie_reset_flr(dev, 1);

	if (rc != -ENOTTY)

		return rc;

	rc = pci_af_flr(dev, 1);

	if (rc != -ENOTTY)

		return rc;

drivers/pci/pcie/aer.c

+5 −7
Original line number Diff line number Diff line
@@ -1407,13 +1407,11 @@ static pci_ers_result_t aer_root_reset(struct pci_dev *dev) 
	}



	if (type == PCI_EXP_TYPE_RC_EC || type == PCI_EXP_TYPE_RC_END) {

		if (pcie_has_flr(dev)) {

			rc = pcie_flr(dev);

			pci_info(dev, "has been reset (%d)\n", rc);

		} else {

			pci_info(dev, "not reset (no FLR support)\n");

			rc = -ENOTTY;

		}

		rc = pcie_reset_flr(dev, 0);

		if (!rc)

			pci_info(dev, "has been reset\n");

		else

			pci_info(dev, "not reset (no FLR support: %d)\n", rc);

	} else {

		rc = pci_bus_error_reset(dev);

		pci_info(dev, "%s Port link has been reset (%d)\n",

drivers/pci/quirks.c

+3 −6
Original line number Diff line number Diff line
@@ -3852,7 +3852,7 @@ static int nvme_disable_and_flr(struct pci_dev *dev, int probe) 
	u32 cfg;



	if (dev->class != PCI_CLASS_STORAGE_EXPRESS ||

	    !pcie_has_flr(dev) || !pci_resource_start(dev, 0))

	    pcie_reset_flr(dev, 1) || !pci_resource_start(dev, 0))

		return -ENOTTY;



	if (probe)
@@ -3921,13 +3921,10 @@ static int nvme_disable_and_flr(struct pci_dev *dev, int probe) 
 */

static int delay_250ms_after_flr(struct pci_dev *dev, int probe)

{

	if (!pcie_has_flr(dev))

		return -ENOTTY;



	if (probe)

		return 0;

		return pcie_reset_flr(dev, 1);



	pcie_flr(dev);

	pcie_reset_flr(dev, 0);



	msleep(250);

include/linux/pci.h

+1 −1
Original line number Diff line number Diff line
@@ -1229,7 +1229,7 @@ u32 pcie_bandwidth_available(struct pci_dev *dev, struct pci_dev **limiting_dev, 
			     enum pci_bus_speed *speed,

			     enum pcie_link_width *width);

void pcie_print_link_status(struct pci_dev *dev);

bool pcie_has_flr(struct pci_dev *dev);

int pcie_reset_flr(struct pci_dev *dev, int probe);

int pcie_flr(struct pci_dev *dev);

int __pci_reset_function_locked(struct pci_dev *dev);

int pci_reset_function(struct pci_dev *dev);