arch/powerpc/kernel/vio.c

   1 /*
   2  * IBM PowerPC Virtual I/O Infrastructure Support.
   3  *
   4  *    Copyright (c) 2003-2005 IBM Corp.
   5  *     Dave Engebretsen engebret@us.ibm.com
   6  *     Santiago Leon santil@us.ibm.com
   7  *     Hollis Blanchard <hollisb@us.ibm.com>
   8  *     Stephen Rothwell
   9  *
  10  *      This program is free software; you can redistribute it and/or
  11  *      modify it under the terms of the GNU General Public License
  12  *      as published by the Free Software Foundation; either version
  13  *      2 of the License, or (at your option) any later version.
  14  */
  15
  16 #include <linux/init.h>
  17 #include <linux/console.h>
  18 #include <linux/module.h>
  19 #include <linux/mm.h>
  20 #include <linux/dma-mapping.h>
  21 #include <asm/iommu.h>
  22 #include <asm/dma.h>
  23 #include <asm/vio.h>
  24 #include <asm/prom.h>
  25
  26 static const struct vio_device_id *vio_match_device(
  27                 const struct vio_device_id *, const struct vio_dev *);
  28
  29 struct vio_dev vio_bus_device  = { /* fake "parent" device */
  30         .name = vio_bus_device.dev.bus_id,
  31         .type = "",
  32         .dev.bus_id = "vio",
  33         .dev.bus = &vio_bus_type,
  34 };
  35
  36 static struct vio_bus_ops vio_bus_ops;
  37
  38 /*
  39  * Convert from struct device to struct vio_dev and pass to driver.
  40  * dev->driver has already been set by generic code because vio_bus_match
  41  * succeeded.
  42  */
  43 static int vio_bus_probe(struct device *dev)
  44 {
  45         struct vio_dev *viodev = to_vio_dev(dev);
  46         struct vio_driver *viodrv = to_vio_driver(dev->driver);
  47         const struct vio_device_id *id;
  48         int error = -ENODEV;
  49
  50         if (!viodrv->probe)
  51                 return error;
  52
  53         id = vio_match_device(viodrv->id_table, viodev);
  54         if (id)
  55                 error = viodrv->probe(viodev, id);
  56
  57         return error;
  58 }
  59
  60 /* convert from struct device to struct vio_dev and pass to driver. */
  61 static int vio_bus_remove(struct device *dev)
  62 {
  63         struct vio_dev *viodev = to_vio_dev(dev);
  64         struct vio_driver *viodrv = to_vio_driver(dev->driver);
  65
  66         if (viodrv->remove)
  67                 return viodrv->remove(viodev);
  68
  69         /* driver can't remove */
  70         return 1;
  71 }
  72
  73 /* convert from struct device to struct vio_dev and pass to driver. */
  74 static void vio_bus_shutdown(struct device *dev)
  75 {
  76         struct vio_dev *viodev = to_vio_dev(dev);
  77         struct vio_driver *viodrv = to_vio_driver(dev->driver);
  78
  79         if (dev->driver && viodrv->shutdown)
  80                 viodrv->shutdown(viodev);
  81 }
  82
  83 /**
  84  * vio_register_driver: - Register a new vio driver
  85  * @drv:        The vio_driver structure to be registered.
  86  */
  87 int vio_register_driver(struct vio_driver *viodrv)
  88 {
  89         printk(KERN_DEBUG "%s: driver %s registering\n", __FUNCTION__,
  90                 viodrv->driver.name);
  91
  92         /* fill in 'struct driver' fields */
  93         viodrv->driver.bus = &vio_bus_type;
  94
  95         return driver_register(&viodrv->driver);
  96 }
  97 EXPORT_SYMBOL(vio_register_driver);
  98
  99 /**
 100  * vio_unregister_driver - Remove registration of vio driver.
 101  * @driver:     The vio_driver struct to be removed form registration
 102  */
 103 void vio_unregister_driver(struct vio_driver *viodrv)
 104 {
 105         driver_unregister(&viodrv->driver);
 106 }
 107 EXPORT_SYMBOL(vio_unregister_driver);
 108
 109 /**
 110  * vio_match_device: - Tell if a VIO device has a matching
 111  *                      VIO device id structure.
 112  * @ids:        array of VIO device id structures to search in
 113  * @dev:        the VIO device structure to match against
 114  *
 115  * Used by a driver to check whether a VIO device present in the
 116  * system is in its list of supported devices. Returns the matching
 117  * vio_device_id structure or NULL if there is no match.
 118  */
 119 static const struct vio_device_id *vio_match_device(
 120                 const struct vio_device_id *ids, const struct vio_dev *dev)
 121 {
 122         while (ids->type[0] != '\0') {
 123                 if (vio_bus_ops.match(ids, dev))
 124                         return ids;
 125                 ids++;
 126         }
 127         return NULL;
 128 }
 129
 130 /**
 131  * vio_bus_init: - Initialize the virtual IO bus
 132  */
 133 int __init vio_bus_init(struct vio_bus_ops *ops)
 134 {
 135         int err;
 136
 137         vio_bus_ops = *ops;
 138
 139         err = bus_register(&vio_bus_type);
 140         if (err) {
 141                 printk(KERN_ERR "failed to register VIO bus\n");
 142                 return err;
 143         }
 144
 145         /*
 146          * The fake parent of all vio devices, just to give us
 147          * a nice directory
 148          */
 149         err = device_register(&vio_bus_device.dev);
 150         if (err) {
 151                 printk(KERN_WARNING "%s: device_register returned %i\n",
 152                                 __FUNCTION__, err);
 153                 return err;
 154         }
 155
 156         return 0;
 157 }
 158
 159 /* vio_dev refcount hit 0 */
 160 static void __devinit vio_dev_release(struct device *dev)
 161 {
 162         if (vio_bus_ops.release_device)
 163                 vio_bus_ops.release_device(dev);
 164         kfree(to_vio_dev(dev));
 165 }
 166
 167 static ssize_t viodev_show_name(struct device *dev,
 168                 struct device_attribute *attr, char *buf)
 169 {
 170         return sprintf(buf, "%s\n", to_vio_dev(dev)->name);
 171 }
 172 DEVICE_ATTR(name, S_IRUSR | S_IRGRP | S_IROTH, viodev_show_name, NULL);
 173
 174 struct vio_dev * __devinit vio_register_device(struct vio_dev *viodev)
 175 {
 176         /* init generic 'struct device' fields: */
 177         viodev->dev.parent = &vio_bus_device.dev;
 178         viodev->dev.bus = &vio_bus_type;
 179         viodev->dev.release = vio_dev_release;
 180
 181         /* register with generic device framework */
 182         if (device_register(&viodev->dev)) {
 183                 printk(KERN_ERR "%s: failed to register device %s\n",
 184                                 __FUNCTION__, viodev->dev.bus_id);
 185                 return NULL;
 186         }
 187         device_create_file(&viodev->dev, &dev_attr_name);
 188
 189         return viodev;
 190 }
 191
 192 void __devinit vio_unregister_device(struct vio_dev *viodev)
 193 {
 194         if (vio_bus_ops.unregister_device)
 195                 vio_bus_ops.unregister_device(viodev);
 196         device_remove_file(&viodev->dev, &dev_attr_name);
 197         device_unregister(&viodev->dev);
 198 }
 199 EXPORT_SYMBOL(vio_unregister_device);
 200
 201 static dma_addr_t vio_map_single(struct device *dev, void *vaddr,
 202                           size_t size, enum dma_data_direction direction)
 203 {
 204         return iommu_map_single(to_vio_dev(dev)->iommu_table, vaddr, size,
 205                         direction);
 206 }
 207
 208 static void vio_unmap_single(struct device *dev, dma_addr_t dma_handle,
 209                       size_t size, enum dma_data_direction direction)
 210 {
 211         iommu_unmap_single(to_vio_dev(dev)->iommu_table, dma_handle, size,
 212                         direction);
 213 }
 214
 215 static int vio_map_sg(struct device *dev, struct scatterlist *sglist,
 216                 int nelems, enum dma_data_direction direction)
 217 {
 218         return iommu_map_sg(dev, to_vio_dev(dev)->iommu_table, sglist,
 219                         nelems, direction);
 220 }
 221
 222 static void vio_unmap_sg(struct device *dev, struct scatterlist *sglist,
 223                 int nelems, enum dma_data_direction direction)
 224 {
 225         iommu_unmap_sg(to_vio_dev(dev)->iommu_table, sglist, nelems, direction);
 226 }
 227
 228 static void *vio_alloc_coherent(struct device *dev, size_t size,
 229                            dma_addr_t *dma_handle, gfp_t flag)
 230 {
 231         return iommu_alloc_coherent(to_vio_dev(dev)->iommu_table, size,
 232                         dma_handle, flag);
 233 }
 234
 235 static void vio_free_coherent(struct device *dev, size_t size,
 236                          void *vaddr, dma_addr_t dma_handle)
 237 {
 238         iommu_free_coherent(to_vio_dev(dev)->iommu_table, size, vaddr,
 239                         dma_handle);
 240 }
 241
 242 static int vio_dma_supported(struct device *dev, u64 mask)
 243 {
 244         return 1;
 245 }
 246
 247 struct dma_mapping_ops vio_dma_ops = {
 248         .alloc_coherent = vio_alloc_coherent,
 249         .free_coherent = vio_free_coherent,
 250         .map_single = vio_map_single,
 251         .unmap_single = vio_unmap_single,
 252         .map_sg = vio_map_sg,
 253         .unmap_sg = vio_unmap_sg,
 254         .dma_supported = vio_dma_supported,
 255 };
 256
 257 static int vio_bus_match(struct device *dev, struct device_driver *drv)
 258 {
 259         const struct vio_dev *vio_dev = to_vio_dev(dev);
 260         struct vio_driver *vio_drv = to_vio_driver(drv);
 261         const struct vio_device_id *ids = vio_drv->id_table;
 262
 263         return (ids != NULL) && (vio_match_device(ids, vio_dev) != NULL);
 264 }
 265
 266 static int vio_hotplug(struct device *dev, char **envp, int num_envp,
 267                         char *buffer, int buffer_size)
 268 {
 269         const struct vio_dev *vio_dev = to_vio_dev(dev);
 270         char *cp;
 271         int length;
 272
 273         if (!num_envp)
 274                 return -ENOMEM;
 275
 276         if (!vio_dev->dev.platform_data)
 277                 return -ENODEV;
 278         cp = (char *)get_property(vio_dev->dev.platform_data, "compatible", &length);
 279         if (!cp)
 280                 return -ENODEV;
 281
 282         envp[0] = buffer;
 283         length = scnprintf(buffer, buffer_size, "MODALIAS=vio:T%sS%s",
 284                                 vio_dev->type, cp);
 285         if (buffer_size - length <= 0)
 286                 return -ENOMEM;
 287         envp[1] = NULL;
 288         return 0;
 289 }
 290
 291 struct bus_type vio_bus_type = {
 292         .name = "vio",
 293         .uevent = vio_hotplug,
 294         .match = vio_bus_match,
 295         .probe = vio_bus_probe,
 296         .remove = vio_bus_remove,
 297         .shutdown = vio_bus_shutdown,
 298 };