arch/ppc64/kernel/pSeries_vio.c

   1 /*
   2  * IBM PowerPC pSeries 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/module.h>
  18 #include <linux/mm.h>
  19 #include <linux/kobject.h>
  20 #include <asm/iommu.h>
  21 #include <asm/dma.h>
  22 #include <asm/prom.h>
  23 #include <asm/vio.h>
  24 #include <asm/hvcall.h>
  25
  26 extern struct subsystem devices_subsys; /* needed for vio_find_name() */
  27
  28 static void probe_bus_pseries(void)
  29 {
  30         struct device_node *node_vroot, *of_node;
  31
  32         node_vroot = find_devices("vdevice");
  33         if ((node_vroot == NULL) || (node_vroot->child == NULL))
  34                 /* this machine doesn't do virtual IO, and that's ok */
  35                 return;
  36
  37         /*
  38          * Create struct vio_devices for each virtual device in the device tree.
  39          * Drivers will associate with them later.
  40          */
  41         for (of_node = node_vroot->child; of_node != NULL;
  42                         of_node = of_node->sibling) {
  43                 printk(KERN_DEBUG "%s: processing %p\n", __FUNCTION__, of_node);
  44                 vio_register_device_node(of_node);
  45         }
  46 }
  47
  48 /**
  49  * vio_match_device_pseries: - Tell if a pSeries VIO device matches a
  50  *      vio_device_id
  51  */
  52 static int vio_match_device_pseries(const struct vio_device_id *id,
  53                 const struct vio_dev *dev)
  54 {
  55         return (strncmp(dev->type, id->type, strlen(id->type)) == 0) &&
  56                         device_is_compatible(dev->dev.platform_data, id->compat);
  57 }
  58
  59 static void vio_release_device_pseries(struct device *dev)
  60 {
  61         /* XXX free TCE table */
  62         of_node_put(dev->platform_data);
  63 }
  64
  65 static ssize_t viodev_show_devspec(struct device *dev,
  66                 struct device_attribute *attr, char *buf)
  67 {
  68         struct device_node *of_node = dev->platform_data;
  69
  70         return sprintf(buf, "%s\n", of_node->full_name);
  71 }
  72 DEVICE_ATTR(devspec, S_IRUSR | S_IRGRP | S_IROTH, viodev_show_devspec, NULL);
  73
  74 static void vio_unregister_device_pseries(struct vio_dev *viodev)
  75 {
  76         device_remove_file(&viodev->dev, &dev_attr_devspec);
  77 }
  78
  79 static struct vio_bus_ops vio_bus_ops_pseries = {
  80         .match = vio_match_device_pseries,
  81         .unregister_device = vio_unregister_device_pseries,
  82         .release_device = vio_release_device_pseries,
  83 };
  84
  85 /**
  86  * vio_bus_init_pseries: - Initialize the pSeries virtual IO bus
  87  */
  88 static int __init vio_bus_init_pseries(void)
  89 {
  90         int err;
  91
  92         err = vio_bus_init(&vio_bus_ops_pseries);
  93         if (err == 0)
  94                 probe_bus_pseries();
  95         return err;
  96 }
  97
  98 __initcall(vio_bus_init_pseries);
  99
 100 /**
 101  * vio_build_iommu_table: - gets the dma information from OF and
 102  *      builds the TCE tree.
 103  * @dev: the virtual device.
 104  *
 105  * Returns a pointer to the built tce tree, or NULL if it can't
 106  * find property.
 107 */
 108 static struct iommu_table *vio_build_iommu_table(struct vio_dev *dev)
 109 {
 110         unsigned int *dma_window;
 111         struct iommu_table *newTceTable;
 112         unsigned long offset;
 113         int dma_window_property_size;
 114
 115         dma_window = (unsigned int *) get_property(dev->dev.platform_data, "ibm,my-dma-window", &dma_window_property_size);
 116         if(!dma_window) {
 117                 return NULL;
 118         }
 119
 120         newTceTable = (struct iommu_table *) kmalloc(sizeof(struct iommu_table), GFP_KERNEL);
 121
 122         /*  There should be some code to extract the phys-encoded offset
 123                 using prom_n_addr_cells(). However, according to a comment
 124                 on earlier versions, it's always zero, so we don't bother */
 125         offset = dma_window[1] >>  PAGE_SHIFT;
 126
 127         /* TCE table size - measured in tce entries */
 128         newTceTable->it_size            = dma_window[4] >> PAGE_SHIFT;
 129         /* offset for VIO should always be 0 */
 130         newTceTable->it_offset          = offset;
 131         newTceTable->it_busno           = 0;
 132         newTceTable->it_index           = (unsigned long)dma_window[0];
 133         newTceTable->it_type            = TCE_VB;
 134
 135         return iommu_init_table(newTceTable);
 136 }
 137
 138 /**
 139  * vio_register_device_node: - Register a new vio device.
 140  * @of_node:    The OF node for this device.
 141  *
 142  * Creates and initializes a vio_dev structure from the data in
 143  * of_node (dev.platform_data) and adds it to the list of virtual devices.
 144  * Returns a pointer to the created vio_dev or NULL if node has
 145  * NULL device_type or compatible fields.
 146  */
 147 struct vio_dev * __devinit vio_register_device_node(struct device_node *of_node)
 148 {
 149         struct vio_dev *viodev;
 150         unsigned int *unit_address;
 151         unsigned int *irq_p;
 152
 153         /* we need the 'device_type' property, in order to match with drivers */
 154         if ((NULL == of_node->type)) {
 155                 printk(KERN_WARNING
 156                         "%s: node %s missing 'device_type'\n", __FUNCTION__,
 157                         of_node->name ? of_node->name : "<unknown>");
 158                 return NULL;
 159         }
 160
 161         unit_address = (unsigned int *)get_property(of_node, "reg", NULL);
 162         if (!unit_address) {
 163                 printk(KERN_WARNING "%s: node %s missing 'reg'\n", __FUNCTION__,
 164                         of_node->name ? of_node->name : "<unknown>");
 165                 return NULL;
 166         }
 167
 168         /* allocate a vio_dev for this node */
 169         viodev = kmalloc(sizeof(struct vio_dev), GFP_KERNEL);
 170         if (!viodev) {
 171                 return NULL;
 172         }
 173         memset(viodev, 0, sizeof(struct vio_dev));
 174
 175         viodev->dev.platform_data = of_node_get(of_node);
 176
 177         viodev->irq = NO_IRQ;
 178         irq_p = (unsigned int *)get_property(of_node, "interrupts", NULL);
 179         if (irq_p) {
 180                 int virq = virt_irq_create_mapping(*irq_p);
 181                 if (virq == NO_IRQ) {
 182                         printk(KERN_ERR "Unable to allocate interrupt "
 183                                "number for %s\n", of_node->full_name);
 184                 } else
 185                         viodev->irq = irq_offset_up(virq);
 186         }
 187
 188         snprintf(viodev->dev.bus_id, BUS_ID_SIZE, "%x", *unit_address);
 189         viodev->name = of_node->name;
 190         viodev->type = of_node->type;
 191         viodev->unit_address = *unit_address;
 192         viodev->iommu_table = vio_build_iommu_table(viodev);
 193
 194         /* register with generic device framework */
 195         if (vio_register_device(viodev) == NULL) {
 196                 /* XXX free TCE table */
 197                 kfree(viodev);
 198                 return NULL;
 199         }
 200         device_create_file(&viodev->dev, &dev_attr_devspec);
 201
 202         return viodev;
 203 }
 204 EXPORT_SYMBOL(vio_register_device_node);
 205
 206 /**
 207  * vio_get_attribute: - get attribute for virtual device
 208  * @vdev:       The vio device to get property.
 209  * @which:      The property/attribute to be extracted.
 210  * @length:     Pointer to length of returned data size (unused if NULL).
 211  *
 212  * Calls prom.c's get_property() to return the value of the
 213  * attribute specified by the preprocessor constant @which
 214 */
 215 const void * vio_get_attribute(struct vio_dev *vdev, void* which, int* length)
 216 {
 217         return get_property(vdev->dev.platform_data, (char*)which, length);
 218 }
 219 EXPORT_SYMBOL(vio_get_attribute);
 220
 221 /* vio_find_name() - internal because only vio.c knows how we formatted the
 222  * kobject name
 223  * XXX once vio_bus_type.devices is actually used as a kset in
 224  * drivers/base/bus.c, this function should be removed in favor of
 225  * "device_find(kobj_name, &vio_bus_type)"
 226  */
 227 static struct vio_dev *vio_find_name(const char *kobj_name)
 228 {
 229         struct kobject *found;
 230
 231         found = kset_find_obj(&devices_subsys.kset, kobj_name);
 232         if (!found)
 233                 return NULL;
 234
 235         return to_vio_dev(container_of(found, struct device, kobj));
 236 }
 237
 238 /**
 239  * vio_find_node - find an already-registered vio_dev
 240  * @vnode: device_node of the virtual device we're looking for
 241  */
 242 struct vio_dev *vio_find_node(struct device_node *vnode)
 243 {
 244         uint32_t *unit_address;
 245         char kobj_name[BUS_ID_SIZE];
 246
 247         /* construct the kobject name from the device node */
 248         unit_address = (uint32_t *)get_property(vnode, "reg", NULL);
 249         if (!unit_address)
 250                 return NULL;
 251         snprintf(kobj_name, BUS_ID_SIZE, "%x", *unit_address);
 252
 253         return vio_find_name(kobj_name);
 254 }
 255 EXPORT_SYMBOL(vio_find_node);
 256
 257 int vio_enable_interrupts(struct vio_dev *dev)
 258 {
 259         int rc = h_vio_signal(dev->unit_address, VIO_IRQ_ENABLE);
 260         if (rc != H_Success)
 261                 printk(KERN_ERR "vio: Error 0x%x enabling interrupts\n", rc);
 262         return rc;
 263 }
 264 EXPORT_SYMBOL(vio_enable_interrupts);
 265
 266 int vio_disable_interrupts(struct vio_dev *dev)
 267 {
 268         int rc = h_vio_signal(dev->unit_address, VIO_IRQ_DISABLE);
 269         if (rc != H_Success)
 270                 printk(KERN_ERR "vio: Error 0x%x disabling interrupts\n", rc);
 271         return rc;
 272 }
 273 EXPORT_SYMBOL(vio_disable_interrupts);