hw/mipsnet.c

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