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