// SPDX-License-Identifier: GPL-2.0
/*
 * PCI Message Signaled Interrupt (MSI).
 *
 * Legacy architecture specific setup and teardown mechanism.
 */
#include "msi.h"

/* Arch hooks */
int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
{
        return -EINVAL;
}

void __weak arch_teardown_msi_irq(unsigned int irq)
{
}

int __weak arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
{
        struct msi_desc *desc;
        int ret;

        /*
         * If an architecture wants to support multiple MSI, it needs to
         * override arch_setup_msi_irqs()
         */
        if (type == PCI_CAP_ID_MSI && nvec > 1)
                return 1;

        msi_for_each_desc(desc, &dev->dev, MSI_DESC_NOTASSOCIATED) {
                ret = arch_setup_msi_irq(dev, desc);
                if (ret)
                        return ret < 0 ? ret : -ENOSPC;
        }

        return 0;
}

void __weak arch_teardown_msi_irqs(struct pci_dev *dev)
{
        struct msi_desc *desc;
        int i;

        msi_for_each_desc(desc, &dev->dev, MSI_DESC_ASSOCIATED) {
                for (i = 0; i < desc->nvec_used; i++)
                        arch_teardown_msi_irq(desc->irq + i);
        }
}

static int pci_msi_setup_check_result(struct pci_dev *dev, int type, int ret)
{
        struct msi_desc *desc;
        int avail = 0;

        if (type != PCI_CAP_ID_MSIX || ret >= 0)
                return ret;

        /* Scan the MSI descriptors for successfully allocated ones. */
        msi_for_each_desc(desc, &dev->dev, MSI_DESC_ASSOCIATED)
                avail++;

        return avail ? avail : ret;
}

int pci_msi_legacy_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
{
        int ret = arch_setup_msi_irqs(dev, nvec, type);

        ret = pci_msi_setup_check_result(dev, type, ret);
        if (!ret)
                ret = msi_device_populate_sysfs(&dev->dev);
        return ret;
}

void pci_msi_legacy_teardown_msi_irqs(struct pci_dev *dev)
{
        msi_device_destroy_sysfs(&dev->dev);
        arch_teardown_msi_irqs(dev);
}