hw/net/mipsnet.c

   1 #include "qemu/osdep.h"
   2 #include "hw/irq.h"
   3 #include "hw/qdev-properties.h"
   4 #include "net/net.h"
   5 #include "qemu/module.h"
   6 #include "trace.h"
   7 #include "hw/sysbus.h"
   8 #include "migration/vmstate.h"
   9 #include "qom/object.h"
  10
  11 /* MIPSnet register offsets */
  12
  13 #define MIPSNET_DEV_ID          0x00
  14 #define MIPSNET_BUSY            0x08
  15 #define MIPSNET_RX_DATA_COUNT   0x0c
  16 #define MIPSNET_TX_DATA_COUNT   0x10
  17 #define MIPSNET_INT_CTL         0x14
  18 # define MIPSNET_INTCTL_TXDONE          0x00000001
  19 # define MIPSNET_INTCTL_RXDONE          0x00000002
  20 # define MIPSNET_INTCTL_TESTBIT         0x80000000
  21 #define MIPSNET_INTERRUPT_INFO  0x18
  22 #define MIPSNET_RX_DATA_BUFFER  0x1c
  23 #define MIPSNET_TX_DATA_BUFFER  0x20
  24
  25 #define MAX_ETH_FRAME_SIZE      1514
  26
  27 #define TYPE_MIPS_NET "mipsnet"
  28 OBJECT_DECLARE_SIMPLE_TYPE(MIPSnetState, MIPS_NET)
  29
  30 struct MIPSnetState {
  31     SysBusDevice parent_obj;
  32
  33     uint32_t busy;
  34     uint32_t rx_count;
  35     uint32_t rx_read;
  36     uint32_t tx_count;
  37     uint32_t tx_written;
  38     uint32_t intctl;
  39     uint8_t rx_buffer[MAX_ETH_FRAME_SIZE];
  40     uint8_t tx_buffer[MAX_ETH_FRAME_SIZE];
  41     MemoryRegion io;
  42     qemu_irq irq;
  43     NICState *nic;
  44     NICConf conf;
  45 };
  46
  47 static void mipsnet_reset(MIPSnetState *s)
  48 {
  49     s->busy = 1;
  50     s->rx_count = 0;
  51     s->rx_read = 0;
  52     s->tx_count = 0;
  53     s->tx_written = 0;
  54     s->intctl = 0;
  55     memset(s->rx_buffer, 0, MAX_ETH_FRAME_SIZE);
  56     memset(s->tx_buffer, 0, MAX_ETH_FRAME_SIZE);
  57 }
  58
  59 static void mipsnet_update_irq(MIPSnetState *s)
  60 {
  61     int isr = !!s->intctl;
  62     trace_mipsnet_irq(isr, s->intctl);
  63     qemu_set_irq(s->irq, isr);
  64 }
  65
  66 static int mipsnet_buffer_full(MIPSnetState *s)
  67 {
  68     if (s->rx_count >= MAX_ETH_FRAME_SIZE) {
  69         return 1;
  70     }
  71     return 0;
  72 }
  73
  74 static int mipsnet_can_receive(NetClientState *nc)
  75 {
  76     MIPSnetState *s = qemu_get_nic_opaque(nc);
  77
  78     if (s->busy) {
  79         return 0;
  80     }
  81     return !mipsnet_buffer_full(s);
  82 }
  83
  84 static ssize_t mipsnet_receive(NetClientState *nc,
  85                                const uint8_t *buf, size_t size)
  86 {
  87     MIPSnetState *s = qemu_get_nic_opaque(nc);
  88
  89     trace_mipsnet_receive(size);
  90     if (!mipsnet_can_receive(nc)) {
  91         return 0;
  92     }
  93
  94     if (size >= sizeof(s->rx_buffer)) {
  95         return 0;
  96     }
  97     s->busy = 1;
  98
  99     /* Just accept everything. */
 100
 101     /* Write packet data. */
 102     memcpy(s->rx_buffer, buf, size);
 103
 104     s->rx_count = size;
 105     s->rx_read = 0;
 106
 107     /* Now we can signal we have received something. */
 108     s->intctl |= MIPSNET_INTCTL_RXDONE;
 109     mipsnet_update_irq(s);
 110
 111     return size;
 112 }
 113
 114 static uint64_t mipsnet_ioport_read(void *opaque, hwaddr addr,
 115                                     unsigned int size)
 116 {
 117     MIPSnetState *s = opaque;
 118     int ret = 0;
 119
 120     addr &= 0x3f;
 121     switch (addr) {
 122     case MIPSNET_DEV_ID:
 123         ret = be32_to_cpu(0x4d495053);          /* MIPS */
 124         break;
 125     case MIPSNET_DEV_ID + 4:
 126         ret = be32_to_cpu(0x4e455430);          /* NET0 */
 127         break;
 128     case MIPSNET_BUSY:
 129         ret = s->busy;
 130         break;
 131     case MIPSNET_RX_DATA_COUNT:
 132         ret = s->rx_count;
 133         break;
 134     case MIPSNET_TX_DATA_COUNT:
 135         ret = s->tx_count;
 136         break;
 137     case MIPSNET_INT_CTL:
 138         ret = s->intctl;
 139         s->intctl &= ~MIPSNET_INTCTL_TESTBIT;
 140         break;
 141     case MIPSNET_INTERRUPT_INFO:
 142         /* XXX: This seems to be a per-VPE interrupt number. */
 143         ret = 0;
 144         break;
 145     case MIPSNET_RX_DATA_BUFFER:
 146         if (s->rx_count) {
 147             s->rx_count--;
 148             ret = s->rx_buffer[s->rx_read++];
 149             if (mipsnet_can_receive(s->nic->ncs)) {
 150                 qemu_flush_queued_packets(qemu_get_queue(s->nic));
 151             }
 152         }
 153         break;
 154     /* Reads as zero. */
 155     case MIPSNET_TX_DATA_BUFFER:
 156     default:
 157         break;
 158     }
 159     trace_mipsnet_read(addr, ret);
 160     return ret;
 161 }
 162
 163 static void mipsnet_ioport_write(void *opaque, hwaddr addr,
 164                                  uint64_t val, unsigned int size)
 165 {
 166     MIPSnetState *s = opaque;
 167
 168     addr &= 0x3f;
 169     trace_mipsnet_write(addr, val);
 170     switch (addr) {
 171     case MIPSNET_TX_DATA_COUNT:
 172         s->tx_count = (val <= MAX_ETH_FRAME_SIZE) ? val : 0;
 173         s->tx_written = 0;
 174         break;
 175     case MIPSNET_INT_CTL:
 176         if (val & MIPSNET_INTCTL_TXDONE) {
 177             s->intctl &= ~MIPSNET_INTCTL_TXDONE;
 178         } else if (val & MIPSNET_INTCTL_RXDONE) {
 179             s->intctl &= ~MIPSNET_INTCTL_RXDONE;
 180         } else if (val & MIPSNET_INTCTL_TESTBIT) {
 181             mipsnet_reset(s);
 182             s->intctl |= MIPSNET_INTCTL_TESTBIT;
 183         } else if (!val) {
 184             /* ACK testbit interrupt, flag was cleared on read. */
 185         }
 186         s->busy = !!s->intctl;
 187         mipsnet_update_irq(s);
 188         if (mipsnet_can_receive(s->nic->ncs)) {
 189             qemu_flush_queued_packets(qemu_get_queue(s->nic));
 190         }
 191         break;
 192     case MIPSNET_TX_DATA_BUFFER:
 193         s->tx_buffer[s->tx_written++] = val;
 194         if ((s->tx_written >= MAX_ETH_FRAME_SIZE)
 195             || (s->tx_written == s->tx_count)) {
 196             /* Send buffer. */
 197             trace_mipsnet_send(s->tx_written);
 198             qemu_send_packet(qemu_get_queue(s->nic),
 199                                 s->tx_buffer, s->tx_written);
 200             s->tx_count = s->tx_written = 0;
 201             s->intctl |= MIPSNET_INTCTL_TXDONE;
 202             s->busy = 1;
 203             mipsnet_update_irq(s);
 204         }
 205         break;
 206     /* Read-only registers */
 207     case MIPSNET_DEV_ID:
 208     case MIPSNET_BUSY:
 209     case MIPSNET_RX_DATA_COUNT:
 210     case MIPSNET_INTERRUPT_INFO:
 211     case MIPSNET_RX_DATA_BUFFER:
 212     default:
 213         break;
 214     }
 215 }
 216
 217 static const VMStateDescription vmstate_mipsnet = {
 218     .name = "mipsnet",
 219     .version_id = 0,
 220     .minimum_version_id = 0,
 221     .fields = (const VMStateField[]) {
 222         VMSTATE_UINT32(busy, MIPSnetState),
 223         VMSTATE_UINT32(rx_count, MIPSnetState),
 224         VMSTATE_UINT32(rx_read, MIPSnetState),
 225         VMSTATE_UINT32(tx_count, MIPSnetState),
 226         VMSTATE_UINT32(tx_written, MIPSnetState),
 227         VMSTATE_UINT32(intctl, MIPSnetState),
 228         VMSTATE_BUFFER(rx_buffer, MIPSnetState),
 229         VMSTATE_BUFFER(tx_buffer, MIPSnetState),
 230         VMSTATE_END_OF_LIST()
 231     }
 232 };
 233
 234 static NetClientInfo net_mipsnet_info = {
 235     .type = NET_CLIENT_DRIVER_NIC,
 236     .size = sizeof(NICState),
 237     .receive = mipsnet_receive,
 238 };
 239
 240 static const MemoryRegionOps mipsnet_ioport_ops = {
 241     .read = mipsnet_ioport_read,
 242     .write = mipsnet_ioport_write,
 243     .impl.min_access_size = 1,
 244     .impl.max_access_size = 4,
 245 };
 246
 247 static void mipsnet_realize(DeviceState *dev, Error **errp)
 248 {
 249     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
 250     MIPSnetState *s = MIPS_NET(dev);
 251
 252     memory_region_init_io(&s->io, OBJECT(dev), &mipsnet_ioport_ops, s,
 253                           "mipsnet-io", 36);
 254     sysbus_init_mmio(sbd, &s->io);
 255     sysbus_init_irq(sbd, &s->irq);
 256
 257     s->nic = qemu_new_nic(&net_mipsnet_info, &s->conf,
 258                           object_get_typename(OBJECT(dev)), dev->id,
 259                           &dev->mem_reentrancy_guard, s);
 260     qemu_format_nic_info_str(qemu_get_queue(s->nic), s->conf.macaddr.a);
 261 }
 262
 263 static void mipsnet_sysbus_reset(DeviceState *dev)
 264 {
 265     MIPSnetState *s = MIPS_NET(dev);
 266     mipsnet_reset(s);
 267 }
 268
 269 static Property mipsnet_properties[] = {
 270     DEFINE_NIC_PROPERTIES(MIPSnetState, conf),
 271     DEFINE_PROP_END_OF_LIST(),
 272 };
 273
 274 static void mipsnet_class_init(ObjectClass *klass, void *data)
 275 {
 276     DeviceClass *dc = DEVICE_CLASS(klass);
 277
 278     dc->realize = mipsnet_realize;
 279     set_bit(DEVICE_CATEGORY_NETWORK, dc->categories);
 280     dc->desc = "MIPS Simulator network device";
 281     dc->reset = mipsnet_sysbus_reset;
 282     dc->vmsd = &vmstate_mipsnet;
 283     device_class_set_props(dc, mipsnet_properties);
 284 }
 285
 286 static const TypeInfo mipsnet_info = {
 287     .name          = TYPE_MIPS_NET,
 288     .parent        = TYPE_SYS_BUS_DEVICE,
 289     .instance_size = sizeof(MIPSnetState),
 290     .class_init    = mipsnet_class_init,
 291 };
 292
 293 static void mipsnet_register_types(void)
 294 {
 295     type_register_static(&mipsnet_info);
 296 }
 297
 298 type_init(mipsnet_register_types)