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 "qemu/osdep.h"
  23 #include "hw/platform-bus.h"
  24 #include "exec/address-spaces.h"
  25 #include "qemu/error-report.h"
  26 #include "sysemu/sysemu.h"
  27
  28
  29 /*
  30  * Returns the PlatformBus IRQ number for a SysBusDevice irq number or -1 if
  31  * the IRQ is not mapped on this Platform bus.
  32  */
  33 int platform_bus_get_irqn(PlatformBusDevice *pbus, SysBusDevice *sbdev,
  34                           int n)
  35 {
  36     qemu_irq sbirq = sysbus_get_connected_irq(sbdev, n);
  37     int i;
  38
  39     for (i = 0; i < pbus->num_irqs; i++) {
  40         if (pbus->irqs[i] == sbirq) {
  41             return i;
  42         }
  43     }
  44
  45     /* IRQ not mapped on platform bus */
  46     return -1;
  47 }
  48
  49 /*
  50  * Returns the PlatformBus MMIO region offset for Region n of a SysBusDevice or
  51  * -1 if the region is not mapped on this Platform bus.
  52  */
  53 hwaddr platform_bus_get_mmio_addr(PlatformBusDevice *pbus, SysBusDevice *sbdev,
  54                                   int n)
  55 {
  56     MemoryRegion *pbus_mr = &pbus->mmio;
  57     MemoryRegion *sbdev_mr = sysbus_mmio_get_region(sbdev, n);
  58     Object *pbus_mr_obj = OBJECT(pbus_mr);
  59     Object *parent_mr;
  60
  61     if (!memory_region_is_mapped(sbdev_mr)) {
  62         /* Region is not mapped? */
  63         return -1;
  64     }
  65
  66     parent_mr = object_property_get_link(OBJECT(sbdev_mr), "container", NULL);
  67
  68     assert(parent_mr);
  69     if (parent_mr != pbus_mr_obj) {
  70         /* MMIO region is not mapped on platform bus */
  71         return -1;
  72     }
  73
  74     return object_property_get_uint(OBJECT(sbdev_mr), "addr", NULL);
  75 }
  76
  77 static void platform_bus_count_irqs(SysBusDevice *sbdev, void *opaque)
  78 {
  79     PlatformBusDevice *pbus = opaque;
  80     qemu_irq sbirq;
  81     int n, i;
  82
  83     for (n = 0; ; n++) {
  84         if (!sysbus_has_irq(sbdev, n)) {
  85             break;
  86         }
  87
  88         sbirq = sysbus_get_connected_irq(sbdev, n);
  89         for (i = 0; i < pbus->num_irqs; i++) {
  90             if (pbus->irqs[i] == sbirq) {
  91                 bitmap_set(pbus->used_irqs, i, 1);
  92                 break;
  93             }
  94         }
  95     }
  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 void 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;
 118     }
 119
 120     irqn = find_first_zero_bit(pbus->used_irqs, max_irqs);
 121     if (irqn >= max_irqs) {
 122         error_report("Platform Bus: Can not fit IRQ line");
 123         exit(1);
 124     }
 125
 126     set_bit(irqn, pbus->used_irqs);
 127     sysbus_connect_irq(sbdev, n, pbus->irqs[irqn]);
 128 }
 129
 130 static void platform_bus_map_mmio(PlatformBusDevice *pbus, SysBusDevice *sbdev,
 131                                   int n)
 132 {
 133     MemoryRegion *sbdev_mr = sysbus_mmio_get_region(sbdev, n);
 134     uint64_t size = memory_region_size(sbdev_mr);
 135     uint64_t alignment = (1ULL << (63 - clz64(size + size - 1)));
 136     uint64_t off;
 137     bool found_region = false;
 138
 139     if (memory_region_is_mapped(sbdev_mr)) {
 140         /* Region is already mapped, nothing to do */
 141         return;
 142     }
 143
 144     /*
 145      * Look for empty space in the MMIO space that is naturally aligned with
 146      * the target device's memory region
 147      */
 148     for (off = 0; off < pbus->mmio_size; off += alignment) {
 149         if (!memory_region_find(&pbus->mmio, off, size).mr) {
 150             found_region = true;
 151             break;
 152         }
 153     }
 154
 155     if (!found_region) {
 156         error_report("Platform Bus: Can not fit MMIO region of size %"PRIx64,
 157                      size);
 158         exit(1);
 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
 165 /*
 166  * For each sysbus device, look for unassigned IRQ lines as well as
 167  * unassociated MMIO regions. Connect them to the platform bus if available.
 168  */
 169 static void link_sysbus_device(SysBusDevice *sbdev, void *opaque)
 170 {
 171     PlatformBusDevice *pbus = opaque;
 172     int i;
 173
 174     for (i = 0; sysbus_has_irq(sbdev, i); i++) {
 175         platform_bus_map_irq(pbus, sbdev, i);
 176     }
 177
 178     for (i = 0; sysbus_has_mmio(sbdev, i); i++) {
 179         platform_bus_map_mmio(pbus, sbdev, i);
 180     }
 181 }
 182
 183 static void platform_bus_init_notify(Notifier *notifier, void *data)
 184 {
 185     PlatformBusDevice *pb = container_of(notifier, PlatformBusDevice, notifier);
 186
 187     /*
 188      * Generate a bitmap of used IRQ lines, as the user might have specified
 189      * them on the command line.
 190      */
 191     plaform_bus_refresh_irqs(pb);
 192
 193     foreach_dynamic_sysbus_device(link_sysbus_device, pb);
 194 }
 195
 196 static void platform_bus_realize(DeviceState *dev, Error **errp)
 197 {
 198     PlatformBusDevice *pbus;
 199     SysBusDevice *d;
 200     int i;
 201
 202     d = SYS_BUS_DEVICE(dev);
 203     pbus = PLATFORM_BUS_DEVICE(dev);
 204
 205     memory_region_init(&pbus->mmio, NULL, "platform bus", pbus->mmio_size);
 206     sysbus_init_mmio(d, &pbus->mmio);
 207
 208     pbus->used_irqs = bitmap_new(pbus->num_irqs);
 209     pbus->irqs = g_new0(qemu_irq, pbus->num_irqs);
 210     for (i = 0; i < pbus->num_irqs; i++) {
 211         sysbus_init_irq(d, &pbus->irqs[i]);
 212     }
 213
 214     /*
 215      * Register notifier that allows us to gather dangling devices once the
 216      * machine is completely assembled
 217      */
 218     pbus->notifier.notify = platform_bus_init_notify;
 219     qemu_add_machine_init_done_notifier(&pbus->notifier);
 220 }
 221
 222 static Property platform_bus_properties[] = {
 223     DEFINE_PROP_UINT32("num_irqs", PlatformBusDevice, num_irqs, 0),
 224     DEFINE_PROP_UINT32("mmio_size", PlatformBusDevice, mmio_size, 0),
 225     DEFINE_PROP_END_OF_LIST()
 226 };
 227
 228 static void platform_bus_class_init(ObjectClass *klass, void *data)
 229 {
 230     DeviceClass *dc = DEVICE_CLASS(klass);
 231
 232     dc->realize = platform_bus_realize;
 233     dc->props = platform_bus_properties;
 234 }
 235
 236 static const TypeInfo platform_bus_info = {
 237     .name          = TYPE_PLATFORM_BUS_DEVICE,
 238     .parent        = TYPE_SYS_BUS_DEVICE,
 239     .instance_size = sizeof(PlatformBusDevice),
 240     .class_init    = platform_bus_class_init,
 241 };
 242
 243 static void platform_bus_register_types(void)
 244 {
 245     type_register_static(&platform_bus_info);
 246 }
 247
 248 type_init(platform_bus_register_types)