hw/core/platform-bus.c

   1 /*
   2  *  Platform Bus device to support dynamic Sysbus devices
   3  *
   4  * Copyright (C) 2014 Freescale Semiconductor, Inc. All rights reserved.
   5  *
   6  * Author: Alexander Graf, <agraf@suse.de>
   7  *
   8  * This library is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2 of the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  20  */
  21
  22 #include "hw/platform-bus.h"
  23 #include "exec/address-spaces.h"
  24 #include "sysemu/sysemu.h"
  25
  26
  27 /*
  28  * Returns the PlatformBus IRQ number for a SysBusDevice irq number or -1 if
  29  * the IRQ is not mapped on this Platform bus.
  30  */
  31 int platform_bus_get_irqn(PlatformBusDevice *pbus, SysBusDevice *sbdev,
  32                           int n)
  33 {
  34     qemu_irq sbirq = sysbus_get_connected_irq(sbdev, n);
  35     int i;
  36
  37     for (i = 0; i < pbus->num_irqs; i++) {
  38         if (pbus->irqs[i] == sbirq) {
  39             return i;
  40         }
  41     }
  42
  43     /* IRQ not mapped on platform bus */
  44     return -1;
  45 }
  46
  47 /*
  48  * Returns the PlatformBus MMIO region offset for Region n of a SysBusDevice or
  49  * -1 if the region is not mapped on this Platform bus.
  50  */
  51 hwaddr platform_bus_get_mmio_addr(PlatformBusDevice *pbus, SysBusDevice *sbdev,
  52                                   int n)
  53 {
  54     MemoryRegion *pbus_mr = &pbus->mmio;
  55     MemoryRegion *sbdev_mr = sysbus_mmio_get_region(sbdev, n);
  56     Object *pbus_mr_obj = OBJECT(pbus_mr);
  57     Object *parent_mr;
  58
  59     if (!memory_region_is_mapped(sbdev_mr)) {
  60         /* Region is not mapped? */
  61         return -1;
  62     }
  63
  64     parent_mr = object_property_get_link(OBJECT(sbdev_mr), "container", NULL);
  65
  66     assert(parent_mr);
  67     if (parent_mr != pbus_mr_obj) {
  68         /* MMIO region is not mapped on platform bus */
  69         return -1;
  70     }
  71
  72     return object_property_get_int(OBJECT(sbdev_mr), "addr", NULL);
  73 }
  74
  75 static int platform_bus_count_irqs(SysBusDevice *sbdev, void *opaque)
  76 {
  77     PlatformBusDevice *pbus = opaque;
  78     qemu_irq sbirq;
  79     int n, i;
  80
  81     for (n = 0; ; n++) {
  82         if (!sysbus_has_irq(sbdev, n)) {
  83             break;
  84         }
  85
  86         sbirq = sysbus_get_connected_irq(sbdev, n);
  87         for (i = 0; i < pbus->num_irqs; i++) {
  88             if (pbus->irqs[i] == sbirq) {
  89                 bitmap_set(pbus->used_irqs, i, 1);
  90                 break;
  91             }
  92         }
  93     }
  94
  95     return 0;
  96 }
  97
  98 /*
  99  * Loop through all sysbus devices and look for unassigned IRQ lines as well as
 100  * unassociated MMIO regions. Connect them to the platform bus if available.
 101  */
 102 static void plaform_bus_refresh_irqs(PlatformBusDevice *pbus)
 103 {
 104     bitmap_zero(pbus->used_irqs, pbus->num_irqs);
 105     foreach_dynamic_sysbus_device(platform_bus_count_irqs, pbus);
 106     pbus->done_gathering = true;
 107 }
 108
 109 static int platform_bus_map_irq(PlatformBusDevice *pbus, SysBusDevice *sbdev,
 110                                 int n)
 111 {
 112     int max_irqs = pbus->num_irqs;
 113     int irqn;
 114
 115     if (sysbus_is_irq_connected(sbdev, n)) {
 116         /* IRQ is already mapped, nothing to do */
 117         return 0;
 118     }
 119
 120     irqn = find_first_zero_bit(pbus->used_irqs, max_irqs);
 121     if (irqn >= max_irqs) {
 122         hw_error("Platform Bus: Can not fit IRQ line");
 123         return -1;
 124     }
 125
 126     set_bit(irqn, pbus->used_irqs);
 127     sysbus_connect_irq(sbdev, n, pbus->irqs[irqn]);
 128
 129     return 0;
 130 }
 131
 132 static int platform_bus_map_mmio(PlatformBusDevice *pbus, SysBusDevice *sbdev,
 133                                  int n)
 134 {
 135     MemoryRegion *sbdev_mr = sysbus_mmio_get_region(sbdev, n);
 136     uint64_t size = memory_region_size(sbdev_mr);
 137     uint64_t alignment = (1ULL << (63 - clz64(size + size - 1)));
 138     uint64_t off;
 139     bool found_region = false;
 140
 141     if (memory_region_is_mapped(sbdev_mr)) {
 142         /* Region is already mapped, nothing to do */
 143         return 0;
 144     }
 145
 146     /*
 147      * Look for empty space in the MMIO space that is naturally aligned with
 148      * the target device's memory region
 149      */
 150     for (off = 0; off < pbus->mmio_size; off += alignment) {
 151         if (!memory_region_find(&pbus->mmio, off, size).mr) {
 152             found_region = true;
 153             break;
 154         }
 155     }
 156
 157     if (!found_region) {
 158         hw_error("Platform Bus: Can not fit MMIO region of size %"PRIx64, size);
 159     }
 160
 161     /* Map the device's region into our Platform Bus MMIO space */
 162     memory_region_add_subregion(&pbus->mmio, off, sbdev_mr);
 163
 164     return 0;
 165 }
 166
 167 /*
 168  * For each sysbus device, look for unassigned IRQ lines as well as
 169  * unassociated MMIO regions. Connect them to the platform bus if available.
 170  */
 171 static int link_sysbus_device(SysBusDevice *sbdev, void *opaque)
 172 {
 173     PlatformBusDevice *pbus = opaque;
 174     int i;
 175
 176     for (i = 0; sysbus_has_irq(sbdev, i); i++) {
 177         platform_bus_map_irq(pbus, sbdev, i);
 178     }
 179
 180     for (i = 0; sysbus_has_mmio(sbdev, i); i++) {
 181         platform_bus_map_mmio(pbus, sbdev, i);
 182     }
 183
 184     return 0;
 185 }
 186
 187 static void platform_bus_init_notify(Notifier *notifier, void *data)
 188 {
 189     PlatformBusDevice *pb = container_of(notifier, PlatformBusDevice, notifier);
 190
 191     /*
 192      * Generate a bitmap of used IRQ lines, as the user might have specified
 193      * them on the command line.
 194      */
 195     plaform_bus_refresh_irqs(pb);
 196
 197     foreach_dynamic_sysbus_device(link_sysbus_device, pb);
 198 }
 199
 200 static void platform_bus_realize(DeviceState *dev, Error **errp)
 201 {
 202     PlatformBusDevice *pbus;
 203     SysBusDevice *d;
 204     int i;
 205
 206     d = SYS_BUS_DEVICE(dev);
 207     pbus = PLATFORM_BUS_DEVICE(dev);
 208
 209     memory_region_init(&pbus->mmio, NULL, "platform bus", pbus->mmio_size);
 210     sysbus_init_mmio(d, &pbus->mmio);
 211
 212     pbus->used_irqs = bitmap_new(pbus->num_irqs);
 213     pbus->irqs = g_new0(qemu_irq, pbus->num_irqs);
 214     for (i = 0; i < pbus->num_irqs; i++) {
 215         sysbus_init_irq(d, &pbus->irqs[i]);
 216     }
 217
 218     /*
 219      * Register notifier that allows us to gather dangling devices once the
 220      * machine is completely assembled
 221      */
 222     pbus->notifier.notify = platform_bus_init_notify;
 223     qemu_add_machine_init_done_notifier(&pbus->notifier);
 224 }
 225
 226 static Property platform_bus_properties[] = {
 227     DEFINE_PROP_UINT32("num_irqs", PlatformBusDevice, num_irqs, 0),
 228     DEFINE_PROP_UINT32("mmio_size", PlatformBusDevice, mmio_size, 0),
 229     DEFINE_PROP_END_OF_LIST()
 230 };
 231
 232 static void platform_bus_class_init(ObjectClass *klass, void *data)
 233 {
 234     DeviceClass *dc = DEVICE_CLASS(klass);
 235
 236     dc->realize = platform_bus_realize;
 237     dc->props = platform_bus_properties;
 238 }
 239
 240 static const TypeInfo platform_bus_info = {
 241     .name          = TYPE_PLATFORM_BUS_DEVICE,
 242     .parent        = TYPE_SYS_BUS_DEVICE,
 243     .instance_size = sizeof(PlatformBusDevice),
 244     .class_init    = platform_bus_class_init,
 245 };
 246
 247 static void platform_bus_register_types(void)
 248 {
 249     type_register_static(&platform_bus_info);
 250 }
 251
 252 type_init(platform_bus_register_types)