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1// SPDX-License-Identifier: GPL-2.02/*3 * PCI Message Signaled Interrupt (MSI).4 *5 * Legacy architecture specific setup and teardown mechanism.6 */7#include "msi.h"8 9/* Arch hooks */10int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)11{12 return -EINVAL;13}14 15void __weak arch_teardown_msi_irq(unsigned int irq)16{17}18 19int __weak arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)20{21 struct msi_desc *desc;22 int ret;23 24 /*25 * If an architecture wants to support multiple MSI, it needs to26 * override arch_setup_msi_irqs()27 */28 if (type == PCI_CAP_ID_MSI && nvec > 1)29 return 1;30 31 msi_for_each_desc(desc, &dev->dev, MSI_DESC_NOTASSOCIATED) {32 ret = arch_setup_msi_irq(dev, desc);33 if (ret)34 return ret < 0 ? ret : -ENOSPC;35 }36 37 return 0;38}39 40void __weak arch_teardown_msi_irqs(struct pci_dev *dev)41{42 struct msi_desc *desc;43 int i;44 45 msi_for_each_desc(desc, &dev->dev, MSI_DESC_ASSOCIATED) {46 for (i = 0; i < desc->nvec_used; i++)47 arch_teardown_msi_irq(desc->irq + i);48 }49}50 51static int pci_msi_setup_check_result(struct pci_dev *dev, int type, int ret)52{53 struct msi_desc *desc;54 int avail = 0;55 56 if (type != PCI_CAP_ID_MSIX || ret >= 0)57 return ret;58 59 /* Scan the MSI descriptors for successfully allocated ones. */60 msi_for_each_desc(desc, &dev->dev, MSI_DESC_ASSOCIATED)61 avail++;62 63 return avail ? avail : ret;64}65 66int pci_msi_legacy_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)67{68 int ret = arch_setup_msi_irqs(dev, nvec, type);69 70 ret = pci_msi_setup_check_result(dev, type, ret);71 if (!ret)72 ret = msi_device_populate_sysfs(&dev->dev);73 return ret;74}75 76void pci_msi_legacy_teardown_msi_irqs(struct pci_dev *dev)77{78 msi_device_destroy_sysfs(&dev->dev);79 arch_teardown_msi_irqs(dev);80}81