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	vdev = vfio_alloc_device(vfio_platform_device, vdev, &adev->dev,
74				 &vfio_amba_ops);
75	if (IS_ERR(vdev))
76		return PTR_ERR(vdev);
77
78	ret = vfio_register_group_dev(&vdev->vdev);
79	if (ret)
80		goto out_put_vdev;
81
82	pm_runtime_enable(&adev->dev);
83	dev_set_drvdata(&adev->dev, vdev);
84	return 0;
85
86out_put_vdev:
87	vfio_put_device(&vdev->vdev);
88	return ret;
89}
90
91static void vfio_amba_release_dev(struct vfio_device *core_vdev)
92{
93	struct vfio_platform_device *vdev =
94		container_of(core_vdev, struct vfio_platform_device, vdev);
95
96	vfio_platform_release_common(vdev);
97	kfree(vdev->name);
98}
99
100static void vfio_amba_remove(struct amba_device *adev)
101{
102	struct vfio_platform_device *vdev = dev_get_drvdata(&adev->dev);
103
104	vfio_unregister_group_dev(&vdev->vdev);
105	pm_runtime_disable(vdev->device);
106	vfio_put_device(&vdev->vdev);
107}
108
109static const struct vfio_device_ops vfio_amba_ops = {
110	.name		= "vfio-amba",
111	.init		= vfio_amba_init_dev,
112	.release	= vfio_amba_release_dev,
113	.open_device	= vfio_platform_open_device,
114	.close_device	= vfio_platform_close_device,
115	.ioctl		= vfio_platform_ioctl,
116	.read		= vfio_platform_read,
117	.write		= vfio_platform_write,
118	.mmap		= vfio_platform_mmap,
119	.bind_iommufd	= vfio_iommufd_physical_bind,
120	.unbind_iommufd	= vfio_iommufd_physical_unbind,
121	.attach_ioas	= vfio_iommufd_physical_attach_ioas,
122	.detach_ioas	= vfio_iommufd_physical_detach_ioas,
123};
124
125static const struct amba_id vfio_amba_ids[] = {
126	{ 0, 0 },
127};
128
129MODULE_DEVICE_TABLE(amba, vfio_amba_ids);
130
131static struct amba_driver vfio_amba_driver = {
132	.probe = vfio_amba_probe,
133	.remove = vfio_amba_remove,
134	.id_table = vfio_amba_ids,
135	.drv = {
136		.name = "vfio-amba",
137		.owner = THIS_MODULE,
138	},
139	.driver_managed_dma = true,
140};
141
142module_amba_driver(vfio_amba_driver);
143
144MODULE_VERSION(DRIVER_VERSION);
145MODULE_LICENSE("GPL v2");
146MODULE_AUTHOR(DRIVER_AUTHOR);
147MODULE_DESCRIPTION(DRIVER_DESC);
148