// 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(sizeof(*vdpa_aux), GFP_KERNEL);
	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);
	vp_modern_remove(&vdpa_aux->vd_mdev);
	pci_free_irq_vectors(vdpa_aux->padev->vf_pdev);

	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");