hw/net/mipsnet.c

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