// SPDX-License-Identifier: GPL-2.0-only
/* Copyright(c) 2023 Advanced Micro Devices, Inc */

#include <linux/auxiliary_bus.h>
#include <linux/pci.h>
#include <linux/vdpa.h>
#include <linux/virtio_pci_modern.h>

#include <linux/pds/pds_common.h>
#include <linux/pds/pds_core_if.h>
#include <linux/pds/pds_adminq.h>
#include <linux/pds/pds_auxbus.h>

#include "aux_drv.h"
#include "debugfs.h"
#include "vdpa_dev.h"

static const struct auxiliary_device_id pds_vdpa_id_table[] = {
        { .name = PDS_VDPA_DEV_NAME, },
        {},
};

static int pds_vdpa_device_id_check(struct pci_dev *pdev)
{
        if (pdev->device != PCI_DEVICE_ID_PENSANDO_VDPA_VF ||
            pdev->vendor != PCI_VENDOR_ID_PENSANDO)
                return -ENODEV;

        return PCI_DEVICE_ID_PENSANDO_VDPA_VF;
}

static int pds_vdpa_probe(struct auxiliary_device *aux_dev,
                          const struct auxiliary_device_id *id)

{
        struct pds_auxiliary_dev *padev =
                container_of(aux_dev, struct pds_auxiliary_dev, aux_dev);
        struct device *dev = &aux_dev->dev;
        struct pds_vdpa_aux *vdpa_aux;
        int err;

        vdpa_aux = kzalloc_obj(*vdpa_aux);
        if (!vdpa_aux)
                return -ENOMEM;

        vdpa_aux->padev = padev;
        vdpa_aux->vf_id = pci_iov_vf_id(padev->vf_pdev);
        auxiliary_set_drvdata(aux_dev, vdpa_aux);

        /* Get device ident info and set up the vdpa_mgmt_dev */
        err = pds_vdpa_get_mgmt_info(vdpa_aux);
        if (err)
                goto err_free_mem;

        /* Find the virtio configuration */
        vdpa_aux->vd_mdev.pci_dev = padev->vf_pdev;
        vdpa_aux->vd_mdev.device_id_check = pds_vdpa_device_id_check;
        vdpa_aux->vd_mdev.dma_mask = DMA_BIT_MASK(PDS_CORE_ADDR_LEN);
        err = vp_modern_probe(&vdpa_aux->vd_mdev);
        if (err) {
                dev_err(dev, "Unable to probe for virtio configuration: %pe\n",
                        ERR_PTR(err));
                goto err_free_mgmt_info;
        }

        /* Let vdpa know that we can provide devices */
        err = vdpa_mgmtdev_register(&vdpa_aux->vdpa_mdev);
        if (err) {
                dev_err(dev, "%s: Failed to initialize vdpa_mgmt interface: %pe\n",
                        __func__, ERR_PTR(err));
                goto err_free_virtio;
        }

        pds_vdpa_debugfs_add_pcidev(vdpa_aux);
        pds_vdpa_debugfs_add_ident(vdpa_aux);

        return 0;

err_free_virtio:
        vp_modern_remove(&vdpa_aux->vd_mdev);
err_free_mgmt_info:
        pci_free_irq_vectors(padev->vf_pdev);
err_free_mem:
        kfree(vdpa_aux);
        auxiliary_set_drvdata(aux_dev, NULL);

        return err;
}

static void pds_vdpa_remove(struct auxiliary_device *aux_dev)
{
        struct pds_vdpa_aux *vdpa_aux = auxiliary_get_drvdata(aux_dev);
        struct device *dev = &aux_dev->dev;

        vdpa_mgmtdev_unregister(&vdpa_aux->vdpa_mdev);
        pds_vdpa_release_irqs(vdpa_aux->pdsv);
        vp_modern_remove(&vdpa_aux->vd_mdev);

        pds_vdpa_debugfs_del_vdpadev(vdpa_aux);
        kfree(vdpa_aux);
        auxiliary_set_drvdata(aux_dev, NULL);

        dev_info(dev, "Removed\n");
}

static struct auxiliary_driver pds_vdpa_driver = {
        .name = PDS_DEV_TYPE_VDPA_STR,
        .probe = pds_vdpa_probe,
        .remove = pds_vdpa_remove,
        .id_table = pds_vdpa_id_table,
};

static void __exit pds_vdpa_cleanup(void)
{
        auxiliary_driver_unregister(&pds_vdpa_driver);

        pds_vdpa_debugfs_destroy();
}
module_exit(pds_vdpa_cleanup);

static int __init pds_vdpa_init(void)
{
        int err;

        pds_vdpa_debugfs_create();

        err = auxiliary_driver_register(&pds_vdpa_driver);
        if (err) {
                pr_err("%s: aux driver register failed: %pe\n",
                       PDS_VDPA_DRV_NAME, ERR_PTR(err));
                pds_vdpa_debugfs_destroy();
        }

        return err;
}
module_init(pds_vdpa_init);

MODULE_DESCRIPTION(PDS_VDPA_DRV_DESCRIPTION);
MODULE_AUTHOR("Advanced Micro Devices, Inc");
MODULE_LICENSE("GPL");