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