vfio_amba.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (C) 2013 - Virtual Open Systems
  4 * Author: Antonios Motakis <a.motakis@virtualopensystems.com>
  5 */
  6
  7#include <linux/module.h>
  8#include <linux/slab.h>
  9#include <linux/vfio.h>
 10#include <linux/pm_runtime.h>
 11#include <linux/amba/bus.h>
 12
 13#include "vfio_platform_private.h"
 14
 15#define DRIVER_VERSION  "0.10"
 16#define DRIVER_AUTHOR   "Antonios Motakis <a.motakis@virtualopensystems.com>"
 17#define DRIVER_DESC     "VFIO for AMBA devices - User Level meta-driver"
 18
 19/* probing devices from the AMBA bus */
 20
 21static struct resource *get_amba_resource(struct vfio_platform_device *vdev,
 22					  int i)
 23{
 24	struct amba_device *adev = (struct amba_device *) vdev->opaque;
 25
 26	if (i == 0)
 27		return &adev->res;
 28
 29	return NULL;
 30}
 31
 32static int get_amba_irq(struct vfio_platform_device *vdev, int i)
 33{
 34	struct amba_device *adev = (struct amba_device *) vdev->opaque;
 35	int ret = 0;
 36
 37	if (i < AMBA_NR_IRQS)
 38		ret = adev->irq[i];
 39
 40	/* zero is an unset IRQ for AMBA devices */
 41	return ret ? ret : -ENXIO;
 42}
 43
 44static int vfio_amba_init_dev(struct vfio_device *core_vdev)
 45{
 46	struct vfio_platform_device *vdev =
 47		container_of(core_vdev, struct vfio_platform_device, vdev);
 48	struct amba_device *adev = to_amba_device(core_vdev->dev);
 49	int ret;
 50
 51	vdev->name = kasprintf(GFP_KERNEL, "vfio-amba-%08x", adev->periphid);
 52	if (!vdev->name)
 53		return -ENOMEM;
 54
 55	vdev->opaque = (void *) adev;
 56	vdev->flags = VFIO_DEVICE_FLAGS_AMBA;
 57	vdev->get_resource = get_amba_resource;
 58	vdev->get_irq = get_amba_irq;
 59	vdev->reset_required = false;
 60
 61	ret = vfio_platform_init_common(vdev);
 62	if (ret)
 63		kfree(vdev->name);
 64	return ret;
 65}
 66
 67static const struct vfio_device_ops vfio_amba_ops;
 68static int vfio_amba_probe(struct amba_device *adev, const struct amba_id *id)
 69{
 70	struct vfio_platform_device *vdev;
 71	int ret;
 72
 73	dev_err_once(&adev->dev, "DEPRECATION: vfio-amba is deprecated and will be removed in a future kernel release\n");
 74
 75	vdev = vfio_alloc_device(vfio_platform_device, vdev, &adev->dev,
 76				 &vfio_amba_ops);
 77	if (IS_ERR(vdev))
 78		return PTR_ERR(vdev);
 79
 80	ret = vfio_register_group_dev(&vdev->vdev);
 81	if (ret)
 82		goto out_put_vdev;
 83
 84	pm_runtime_enable(&adev->dev);
 85	dev_set_drvdata(&adev->dev, vdev);
 86	return 0;
 87
 88out_put_vdev:
 89	vfio_put_device(&vdev->vdev);
 90	return ret;
 91}
 92
 93static void vfio_amba_release_dev(struct vfio_device *core_vdev)
 94{
 95	struct vfio_platform_device *vdev =
 96		container_of(core_vdev, struct vfio_platform_device, vdev);
 97
 98	vfio_platform_release_common(vdev);
 99	kfree(vdev->name);
100}
101
102static void vfio_amba_remove(struct amba_device *adev)
103{
104	struct vfio_platform_device *vdev = dev_get_drvdata(&adev->dev);
105
106	vfio_unregister_group_dev(&vdev->vdev);
107	pm_runtime_disable(vdev->device);
108	vfio_put_device(&vdev->vdev);
109}
110
111static const struct vfio_device_ops vfio_amba_ops = {
112	.name		= "vfio-amba",
113	.init		= vfio_amba_init_dev,
114	.release	= vfio_amba_release_dev,
115	.open_device	= vfio_platform_open_device,
116	.close_device	= vfio_platform_close_device,
117	.ioctl		= vfio_platform_ioctl,
118	.get_region_info_caps = vfio_platform_ioctl_get_region_info,
119	.read		= vfio_platform_read,
120	.write		= vfio_platform_write,
121	.mmap		= vfio_platform_mmap,
122	.bind_iommufd	= vfio_iommufd_physical_bind,
123	.unbind_iommufd	= vfio_iommufd_physical_unbind,
124	.attach_ioas	= vfio_iommufd_physical_attach_ioas,
125	.detach_ioas	= vfio_iommufd_physical_detach_ioas,
126};
127
128static const struct amba_id vfio_amba_ids[] = {
129	{ 0, 0 },
130};
131
132MODULE_DEVICE_TABLE(amba, vfio_amba_ids);
133
134static struct amba_driver vfio_amba_driver = {
135	.probe = vfio_amba_probe,
136	.remove = vfio_amba_remove,
137	.id_table = vfio_amba_ids,
138	.drv = {
139		.name = "vfio-amba",
140	},
141	.driver_managed_dma = true,
142};
143
144module_amba_driver(vfio_amba_driver);
145
146MODULE_VERSION(DRIVER_VERSION);
147MODULE_LICENSE("GPL v2");
148MODULE_AUTHOR(DRIVER_AUTHOR);
149MODULE_DESCRIPTION(DRIVER_DESC);