drivers/vfio/platform/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/amba/bus.h>
  11
  12 #include "vfio_platform_private.h"
  13
  14 #define DRIVER_VERSION  "0.10"
  15 #define DRIVER_AUTHOR   "Antonios Motakis <a.motakis@virtualopensystems.com>"
  16 #define DRIVER_DESC     "VFIO for AMBA devices - User Level meta-driver"
  17
  18 /* probing devices from the AMBA bus */
  19
  20 static struct resource *get_amba_resource(struct vfio_platform_device *vdev,
  21                                           int i)
  22 {
  23         struct amba_device *adev = (struct amba_device *) vdev->opaque;
  24
  25         if (i == 0)
  26                 return &adev->res;
  27
  28         return NULL;
  29 }
  30
  31 static int get_amba_irq(struct vfio_platform_device *vdev, int i)
  32 {
  33         struct amba_device *adev = (struct amba_device *) vdev->opaque;
  34         int ret = 0;
  35
  36         if (i < AMBA_NR_IRQS)
  37                 ret = adev->irq[i];
  38
  39         /* zero is an unset IRQ for AMBA devices */
  40         return ret ? ret : -ENXIO;
  41 }
  42
  43 static int vfio_amba_probe(struct amba_device *adev, const struct amba_id *id)
  44 {
  45         struct vfio_platform_device *vdev;
  46         int ret;
  47
  48         vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
  49         if (!vdev)
  50                 return -ENOMEM;
  51
  52         vdev->name = kasprintf(GFP_KERNEL, "vfio-amba-%08x", adev->periphid);
  53         if (!vdev->name) {
  54                 kfree(vdev);
  55                 return -ENOMEM;
  56         }
  57
  58         vdev->opaque = (void *) adev;
  59         vdev->flags = VFIO_DEVICE_FLAGS_AMBA;
  60         vdev->get_resource = get_amba_resource;
  61         vdev->get_irq = get_amba_irq;
  62         vdev->parent_module = THIS_MODULE;
  63         vdev->reset_required = false;
  64
  65         ret = vfio_platform_probe_common(vdev, &adev->dev);
  66         if (ret) {
  67                 kfree(vdev->name);
  68                 kfree(vdev);
  69         }
  70
  71         return ret;
  72 }
  73
  74 static int vfio_amba_remove(struct amba_device *adev)
  75 {
  76         struct vfio_platform_device *vdev;
  77
  78         vdev = vfio_platform_remove_common(&adev->dev);
  79         if (vdev) {
  80                 kfree(vdev->name);
  81                 kfree(vdev);
  82                 return 0;
  83         }
  84
  85         return -EINVAL;
  86 }
  87
  88 static const struct amba_id pl330_ids[] = {
  89         { 0, 0 },
  90 };
  91
  92 MODULE_DEVICE_TABLE(amba, pl330_ids);
  93
  94 static struct amba_driver vfio_amba_driver = {
  95         .probe = vfio_amba_probe,
  96         .remove = vfio_amba_remove,
  97         .id_table = pl330_ids,
  98         .drv = {
  99                 .name = "vfio-amba",
 100                 .owner = THIS_MODULE,
 101         },
 102 };
 103
 104 module_amba_driver(vfio_amba_driver);
 105
 106 MODULE_VERSION(DRIVER_VERSION);
 107 MODULE_LICENSE("GPL v2");
 108 MODULE_AUTHOR(DRIVER_AUTHOR);
 109 MODULE_DESCRIPTION(DRIVER_DESC);