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mcf_fec.c (18825B)


      1 /*
      2  * ColdFire Fast Ethernet Controller emulation.
      3  *
      4  * Copyright (c) 2007 CodeSourcery.
      5  *
      6  * This code is licensed under the GPL
      7  */
      8 
      9 #include "qemu/osdep.h"
     10 #include "qemu/log.h"
     11 #include "hw/irq.h"
     12 #include "net/net.h"
     13 #include "qemu/module.h"
     14 #include "hw/m68k/mcf.h"
     15 #include "hw/m68k/mcf_fec.h"
     16 #include "hw/net/mii.h"
     17 #include "hw/qdev-properties.h"
     18 #include "hw/sysbus.h"
     19 /* For crc32 */
     20 #include <zlib.h>
     21 
     22 //#define DEBUG_FEC 1
     23 
     24 #ifdef DEBUG_FEC
     25 #define DPRINTF(fmt, ...) \
     26 do { printf("mcf_fec: " fmt , ## __VA_ARGS__); } while (0)
     27 #else
     28 #define DPRINTF(fmt, ...) do {} while(0)
     29 #endif
     30 
     31 #define FEC_MAX_DESC 1024
     32 #define FEC_MAX_FRAME_SIZE 2032
     33 #define FEC_MIB_SIZE 64
     34 
     35 struct mcf_fec_state {
     36     SysBusDevice parent_obj;
     37 
     38     MemoryRegion iomem;
     39     qemu_irq irq[FEC_NUM_IRQ];
     40     NICState *nic;
     41     NICConf conf;
     42     uint32_t irq_state;
     43     uint32_t eir;
     44     uint32_t eimr;
     45     int rx_enabled;
     46     uint32_t rx_descriptor;
     47     uint32_t tx_descriptor;
     48     uint32_t ecr;
     49     uint32_t mmfr;
     50     uint32_t mscr;
     51     uint32_t rcr;
     52     uint32_t tcr;
     53     uint32_t tfwr;
     54     uint32_t rfsr;
     55     uint32_t erdsr;
     56     uint32_t etdsr;
     57     uint32_t emrbr;
     58     uint32_t mib[FEC_MIB_SIZE];
     59 };
     60 
     61 #define FEC_INT_HB   0x80000000
     62 #define FEC_INT_BABR 0x40000000
     63 #define FEC_INT_BABT 0x20000000
     64 #define FEC_INT_GRA  0x10000000
     65 #define FEC_INT_TXF  0x08000000
     66 #define FEC_INT_TXB  0x04000000
     67 #define FEC_INT_RXF  0x02000000
     68 #define FEC_INT_RXB  0x01000000
     69 #define FEC_INT_MII  0x00800000
     70 #define FEC_INT_EB   0x00400000
     71 #define FEC_INT_LC   0x00200000
     72 #define FEC_INT_RL   0x00100000
     73 #define FEC_INT_UN   0x00080000
     74 
     75 #define FEC_EN      2
     76 #define FEC_RESET   1
     77 
     78 /* Map interrupt flags onto IRQ lines.  */
     79 static const uint32_t mcf_fec_irq_map[FEC_NUM_IRQ] = {
     80     FEC_INT_TXF,
     81     FEC_INT_TXB,
     82     FEC_INT_UN,
     83     FEC_INT_RL,
     84     FEC_INT_RXF,
     85     FEC_INT_RXB,
     86     FEC_INT_MII,
     87     FEC_INT_LC,
     88     FEC_INT_HB,
     89     FEC_INT_GRA,
     90     FEC_INT_EB,
     91     FEC_INT_BABT,
     92     FEC_INT_BABR
     93 };
     94 
     95 /* Buffer Descriptor.  */
     96 typedef struct {
     97     uint16_t flags;
     98     uint16_t length;
     99     uint32_t data;
    100 } mcf_fec_bd;
    101 
    102 #define FEC_BD_R    0x8000
    103 #define FEC_BD_E    0x8000
    104 #define FEC_BD_O1   0x4000
    105 #define FEC_BD_W    0x2000
    106 #define FEC_BD_O2   0x1000
    107 #define FEC_BD_L    0x0800
    108 #define FEC_BD_TC   0x0400
    109 #define FEC_BD_ABC  0x0200
    110 #define FEC_BD_M    0x0100
    111 #define FEC_BD_BC   0x0080
    112 #define FEC_BD_MC   0x0040
    113 #define FEC_BD_LG   0x0020
    114 #define FEC_BD_NO   0x0010
    115 #define FEC_BD_CR   0x0004
    116 #define FEC_BD_OV   0x0002
    117 #define FEC_BD_TR   0x0001
    118 
    119 #define MIB_RMON_T_DROP         0
    120 #define MIB_RMON_T_PACKETS      1
    121 #define MIB_RMON_T_BC_PKT       2
    122 #define MIB_RMON_T_MC_PKT       3
    123 #define MIB_RMON_T_CRC_ALIGN    4
    124 #define MIB_RMON_T_UNDERSIZE    5
    125 #define MIB_RMON_T_OVERSIZE     6
    126 #define MIB_RMON_T_FRAG         7
    127 #define MIB_RMON_T_JAB          8
    128 #define MIB_RMON_T_COL          9
    129 #define MIB_RMON_T_P64          10
    130 #define MIB_RMON_T_P65TO127     11
    131 #define MIB_RMON_T_P128TO255    12
    132 #define MIB_RMON_T_P256TO511    13
    133 #define MIB_RMON_T_P512TO1023   14
    134 #define MIB_RMON_T_P1024TO2047  15
    135 #define MIB_RMON_T_P_GTE2048    16
    136 #define MIB_RMON_T_OCTETS       17
    137 #define MIB_IEEE_T_DROP         18
    138 #define MIB_IEEE_T_FRAME_OK     19
    139 #define MIB_IEEE_T_1COL         20
    140 #define MIB_IEEE_T_MCOL         21
    141 #define MIB_IEEE_T_DEF          22
    142 #define MIB_IEEE_T_LCOL         23
    143 #define MIB_IEEE_T_EXCOL        24
    144 #define MIB_IEEE_T_MACERR       25
    145 #define MIB_IEEE_T_CSERR        26
    146 #define MIB_IEEE_T_SQE          27
    147 #define MIB_IEEE_T_FDXFC        28
    148 #define MIB_IEEE_T_OCTETS_OK    29
    149 
    150 #define MIB_RMON_R_DROP         32
    151 #define MIB_RMON_R_PACKETS      33
    152 #define MIB_RMON_R_BC_PKT       34
    153 #define MIB_RMON_R_MC_PKT       35
    154 #define MIB_RMON_R_CRC_ALIGN    36
    155 #define MIB_RMON_R_UNDERSIZE    37
    156 #define MIB_RMON_R_OVERSIZE     38
    157 #define MIB_RMON_R_FRAG         39
    158 #define MIB_RMON_R_JAB          40
    159 #define MIB_RMON_R_RESVD_0      41
    160 #define MIB_RMON_R_P64          42
    161 #define MIB_RMON_R_P65TO127     43
    162 #define MIB_RMON_R_P128TO255    44
    163 #define MIB_RMON_R_P256TO511    45
    164 #define MIB_RMON_R_P512TO1023   46
    165 #define MIB_RMON_R_P1024TO2047  47
    166 #define MIB_RMON_R_P_GTE2048    48
    167 #define MIB_RMON_R_OCTETS       49
    168 #define MIB_IEEE_R_DROP         50
    169 #define MIB_IEEE_R_FRAME_OK     51
    170 #define MIB_IEEE_R_CRC          52
    171 #define MIB_IEEE_R_ALIGN        53
    172 #define MIB_IEEE_R_MACERR       54
    173 #define MIB_IEEE_R_FDXFC        55
    174 #define MIB_IEEE_R_OCTETS_OK    56
    175 
    176 static void mcf_fec_read_bd(mcf_fec_bd *bd, uint32_t addr)
    177 {
    178     cpu_physical_memory_read(addr, bd, sizeof(*bd));
    179     be16_to_cpus(&bd->flags);
    180     be16_to_cpus(&bd->length);
    181     be32_to_cpus(&bd->data);
    182 }
    183 
    184 static void mcf_fec_write_bd(mcf_fec_bd *bd, uint32_t addr)
    185 {
    186     mcf_fec_bd tmp;
    187     tmp.flags = cpu_to_be16(bd->flags);
    188     tmp.length = cpu_to_be16(bd->length);
    189     tmp.data = cpu_to_be32(bd->data);
    190     cpu_physical_memory_write(addr, &tmp, sizeof(tmp));
    191 }
    192 
    193 static void mcf_fec_update(mcf_fec_state *s)
    194 {
    195     uint32_t active;
    196     uint32_t changed;
    197     uint32_t mask;
    198     int i;
    199 
    200     active = s->eir & s->eimr;
    201     changed = active ^s->irq_state;
    202     for (i = 0; i < FEC_NUM_IRQ; i++) {
    203         mask = mcf_fec_irq_map[i];
    204         if (changed & mask) {
    205             DPRINTF("IRQ %d = %d\n", i, (active & mask) != 0);
    206             qemu_set_irq(s->irq[i], (active & mask) != 0);
    207         }
    208     }
    209     s->irq_state = active;
    210 }
    211 
    212 static void mcf_fec_tx_stats(mcf_fec_state *s, int size)
    213 {
    214     s->mib[MIB_RMON_T_PACKETS]++;
    215     s->mib[MIB_RMON_T_OCTETS] += size;
    216     if (size < 64) {
    217         s->mib[MIB_RMON_T_FRAG]++;
    218     } else if (size == 64) {
    219         s->mib[MIB_RMON_T_P64]++;
    220     } else if (size < 128) {
    221         s->mib[MIB_RMON_T_P65TO127]++;
    222     } else if (size < 256) {
    223         s->mib[MIB_RMON_T_P128TO255]++;
    224     } else if (size < 512) {
    225         s->mib[MIB_RMON_T_P256TO511]++;
    226     } else if (size < 1024) {
    227         s->mib[MIB_RMON_T_P512TO1023]++;
    228     } else if (size < 2048) {
    229         s->mib[MIB_RMON_T_P1024TO2047]++;
    230     } else {
    231         s->mib[MIB_RMON_T_P_GTE2048]++;
    232     }
    233     s->mib[MIB_IEEE_T_FRAME_OK]++;
    234     s->mib[MIB_IEEE_T_OCTETS_OK] += size;
    235 }
    236 
    237 static void mcf_fec_do_tx(mcf_fec_state *s)
    238 {
    239     uint32_t addr;
    240     mcf_fec_bd bd;
    241     int frame_size;
    242     int len, descnt = 0;
    243     uint8_t frame[FEC_MAX_FRAME_SIZE];
    244     uint8_t *ptr;
    245 
    246     DPRINTF("do_tx\n");
    247     ptr = frame;
    248     frame_size = 0;
    249     addr = s->tx_descriptor;
    250     while (descnt++ < FEC_MAX_DESC) {
    251         mcf_fec_read_bd(&bd, addr);
    252         DPRINTF("tx_bd %x flags %04x len %d data %08x\n",
    253                 addr, bd.flags, bd.length, bd.data);
    254         if ((bd.flags & FEC_BD_R) == 0) {
    255             /* Run out of descriptors to transmit.  */
    256             break;
    257         }
    258         len = bd.length;
    259         if (frame_size + len > FEC_MAX_FRAME_SIZE) {
    260             len = FEC_MAX_FRAME_SIZE - frame_size;
    261             s->eir |= FEC_INT_BABT;
    262         }
    263         cpu_physical_memory_read(bd.data, ptr, len);
    264         ptr += len;
    265         frame_size += len;
    266         if (bd.flags & FEC_BD_L) {
    267             /* Last buffer in frame.  */
    268             DPRINTF("Sending packet\n");
    269             qemu_send_packet(qemu_get_queue(s->nic), frame, frame_size);
    270             mcf_fec_tx_stats(s, frame_size);
    271             ptr = frame;
    272             frame_size = 0;
    273             s->eir |= FEC_INT_TXF;
    274         }
    275         s->eir |= FEC_INT_TXB;
    276         bd.flags &= ~FEC_BD_R;
    277         /* Write back the modified descriptor.  */
    278         mcf_fec_write_bd(&bd, addr);
    279         /* Advance to the next descriptor.  */
    280         if ((bd.flags & FEC_BD_W) != 0) {
    281             addr = s->etdsr;
    282         } else {
    283             addr += 8;
    284         }
    285     }
    286     s->tx_descriptor = addr;
    287 }
    288 
    289 static void mcf_fec_enable_rx(mcf_fec_state *s)
    290 {
    291     NetClientState *nc = qemu_get_queue(s->nic);
    292     mcf_fec_bd bd;
    293 
    294     mcf_fec_read_bd(&bd, s->rx_descriptor);
    295     s->rx_enabled = ((bd.flags & FEC_BD_E) != 0);
    296     if (s->rx_enabled) {
    297         qemu_flush_queued_packets(nc);
    298     }
    299 }
    300 
    301 static void mcf_fec_reset(DeviceState *dev)
    302 {
    303     mcf_fec_state *s = MCF_FEC_NET(dev);
    304 
    305     s->eir = 0;
    306     s->eimr = 0;
    307     s->rx_enabled = 0;
    308     s->ecr = 0;
    309     s->mscr = 0;
    310     s->rcr = 0x05ee0001;
    311     s->tcr = 0;
    312     s->tfwr = 0;
    313     s->rfsr = 0x500;
    314 }
    315 
    316 #define MMFR_WRITE_OP   (1 << 28)
    317 #define MMFR_READ_OP    (2 << 28)
    318 #define MMFR_PHYADDR(v) (((v) >> 23) & 0x1f)
    319 #define MMFR_REGNUM(v)  (((v) >> 18) & 0x1f)
    320 
    321 static uint64_t mcf_fec_read_mdio(mcf_fec_state *s)
    322 {
    323     uint64_t v;
    324 
    325     if (s->mmfr & MMFR_WRITE_OP)
    326         return s->mmfr;
    327     if (MMFR_PHYADDR(s->mmfr) != 1)
    328         return s->mmfr |= 0xffff;
    329 
    330     switch (MMFR_REGNUM(s->mmfr)) {
    331     case MII_BMCR:
    332         v = MII_BMCR_SPEED | MII_BMCR_AUTOEN | MII_BMCR_FD;
    333         break;
    334     case MII_BMSR:
    335         v = MII_BMSR_100TX_FD | MII_BMSR_100TX_HD | MII_BMSR_10T_FD |
    336             MII_BMSR_10T_HD | MII_BMSR_MFPS | MII_BMSR_AN_COMP |
    337             MII_BMSR_AUTONEG | MII_BMSR_LINK_ST;
    338         break;
    339     case MII_PHYID1:
    340         v = DP83848_PHYID1;
    341         break;
    342     case MII_PHYID2:
    343         v = DP83848_PHYID2;
    344         break;
    345     case MII_ANAR:
    346         v = MII_ANAR_TXFD | MII_ANAR_TX | MII_ANAR_10FD |
    347             MII_ANAR_10 | MII_ANAR_CSMACD;
    348         break;
    349     case MII_ANLPAR:
    350         v = MII_ANLPAR_ACK | MII_ANLPAR_TXFD | MII_ANLPAR_TX |
    351             MII_ANLPAR_10FD | MII_ANLPAR_10 | MII_ANLPAR_CSMACD;
    352         break;
    353     default:
    354         v = 0xffff;
    355         break;
    356     }
    357     s->mmfr = (s->mmfr & ~0xffff) | v;
    358     return s->mmfr;
    359 }
    360 
    361 static uint64_t mcf_fec_read(void *opaque, hwaddr addr,
    362                              unsigned size)
    363 {
    364     mcf_fec_state *s = (mcf_fec_state *)opaque;
    365     switch (addr & 0x3ff) {
    366     case 0x004: return s->eir;
    367     case 0x008: return s->eimr;
    368     case 0x010: return s->rx_enabled ? (1 << 24) : 0; /* RDAR */
    369     case 0x014: return 0; /* TDAR */
    370     case 0x024: return s->ecr;
    371     case 0x040: return mcf_fec_read_mdio(s);
    372     case 0x044: return s->mscr;
    373     case 0x064: return 0; /* MIBC */
    374     case 0x084: return s->rcr;
    375     case 0x0c4: return s->tcr;
    376     case 0x0e4: /* PALR */
    377         return (s->conf.macaddr.a[0] << 24) | (s->conf.macaddr.a[1] << 16)
    378               | (s->conf.macaddr.a[2] << 8) | s->conf.macaddr.a[3];
    379         break;
    380     case 0x0e8: /* PAUR */
    381         return (s->conf.macaddr.a[4] << 24) | (s->conf.macaddr.a[5] << 16) | 0x8808;
    382     case 0x0ec: return 0x10000; /* OPD */
    383     case 0x118: return 0;
    384     case 0x11c: return 0;
    385     case 0x120: return 0;
    386     case 0x124: return 0;
    387     case 0x144: return s->tfwr;
    388     case 0x14c: return 0x600;
    389     case 0x150: return s->rfsr;
    390     case 0x180: return s->erdsr;
    391     case 0x184: return s->etdsr;
    392     case 0x188: return s->emrbr;
    393     case 0x200 ... 0x2e0: return s->mib[(addr & 0x1ff) / 4];
    394     default:
    395         qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad address 0x%" HWADDR_PRIX "\n",
    396                       __func__, addr);
    397         return 0;
    398     }
    399 }
    400 
    401 static void mcf_fec_write(void *opaque, hwaddr addr,
    402                           uint64_t value, unsigned size)
    403 {
    404     mcf_fec_state *s = (mcf_fec_state *)opaque;
    405     switch (addr & 0x3ff) {
    406     case 0x004:
    407         s->eir &= ~value;
    408         break;
    409     case 0x008:
    410         s->eimr = value;
    411         break;
    412     case 0x010: /* RDAR */
    413         if ((s->ecr & FEC_EN) && !s->rx_enabled) {
    414             DPRINTF("RX enable\n");
    415             mcf_fec_enable_rx(s);
    416         }
    417         break;
    418     case 0x014: /* TDAR */
    419         if (s->ecr & FEC_EN) {
    420             mcf_fec_do_tx(s);
    421         }
    422         break;
    423     case 0x024:
    424         s->ecr = value;
    425         if (value & FEC_RESET) {
    426             DPRINTF("Reset\n");
    427             mcf_fec_reset(opaque);
    428         }
    429         if ((s->ecr & FEC_EN) == 0) {
    430             s->rx_enabled = 0;
    431         }
    432         break;
    433     case 0x040:
    434         s->mmfr = value;
    435         s->eir |= FEC_INT_MII;
    436         break;
    437     case 0x044:
    438         s->mscr = value & 0xfe;
    439         break;
    440     case 0x064:
    441         /* TODO: Implement MIB.  */
    442         break;
    443     case 0x084:
    444         s->rcr = value & 0x07ff003f;
    445         /* TODO: Implement LOOP mode.  */
    446         break;
    447     case 0x0c4: /* TCR */
    448         /* We transmit immediately, so raise GRA immediately.  */
    449         s->tcr = value;
    450         if (value & 1)
    451             s->eir |= FEC_INT_GRA;
    452         break;
    453     case 0x0e4: /* PALR */
    454         s->conf.macaddr.a[0] = value >> 24;
    455         s->conf.macaddr.a[1] = value >> 16;
    456         s->conf.macaddr.a[2] = value >> 8;
    457         s->conf.macaddr.a[3] = value;
    458         break;
    459     case 0x0e8: /* PAUR */
    460         s->conf.macaddr.a[4] = value >> 24;
    461         s->conf.macaddr.a[5] = value >> 16;
    462         break;
    463     case 0x0ec:
    464         /* OPD */
    465         break;
    466     case 0x118:
    467     case 0x11c:
    468     case 0x120:
    469     case 0x124:
    470         /* TODO: implement MAC hash filtering.  */
    471         break;
    472     case 0x144:
    473         s->tfwr = value & 3;
    474         break;
    475     case 0x14c:
    476         /* FRBR writes ignored.  */
    477         break;
    478     case 0x150:
    479         s->rfsr = (value & 0x3fc) | 0x400;
    480         break;
    481     case 0x180:
    482         s->erdsr = value & ~3;
    483         s->rx_descriptor = s->erdsr;
    484         break;
    485     case 0x184:
    486         s->etdsr = value & ~3;
    487         s->tx_descriptor = s->etdsr;
    488         break;
    489     case 0x188:
    490         s->emrbr = value > 0 ? value & 0x7F0 : 0x7F0;
    491         break;
    492     case 0x200 ... 0x2e0:
    493         s->mib[(addr & 0x1ff) / 4] = value;
    494         break;
    495     default:
    496         qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad address 0x%" HWADDR_PRIX "\n",
    497                       __func__, addr);
    498         return;
    499     }
    500     mcf_fec_update(s);
    501 }
    502 
    503 static void mcf_fec_rx_stats(mcf_fec_state *s, int size)
    504 {
    505     s->mib[MIB_RMON_R_PACKETS]++;
    506     s->mib[MIB_RMON_R_OCTETS] += size;
    507     if (size < 64) {
    508         s->mib[MIB_RMON_R_FRAG]++;
    509     } else if (size == 64) {
    510         s->mib[MIB_RMON_R_P64]++;
    511     } else if (size < 128) {
    512         s->mib[MIB_RMON_R_P65TO127]++;
    513     } else if (size < 256) {
    514         s->mib[MIB_RMON_R_P128TO255]++;
    515     } else if (size < 512) {
    516         s->mib[MIB_RMON_R_P256TO511]++;
    517     } else if (size < 1024) {
    518         s->mib[MIB_RMON_R_P512TO1023]++;
    519     } else if (size < 2048) {
    520         s->mib[MIB_RMON_R_P1024TO2047]++;
    521     } else {
    522         s->mib[MIB_RMON_R_P_GTE2048]++;
    523     }
    524     s->mib[MIB_IEEE_R_FRAME_OK]++;
    525     s->mib[MIB_IEEE_R_OCTETS_OK] += size;
    526 }
    527 
    528 static int mcf_fec_have_receive_space(mcf_fec_state *s, size_t want)
    529 {
    530     mcf_fec_bd bd;
    531     uint32_t addr;
    532 
    533     /* Walk descriptor list to determine if we have enough buffer */
    534     addr = s->rx_descriptor;
    535     while (want > 0) {
    536         mcf_fec_read_bd(&bd, addr);
    537         if ((bd.flags & FEC_BD_E) == 0) {
    538             return 0;
    539         }
    540         if (want < s->emrbr) {
    541             return 1;
    542         }
    543         want -= s->emrbr;
    544         /* Advance to the next descriptor.  */
    545         if ((bd.flags & FEC_BD_W) != 0) {
    546             addr = s->erdsr;
    547         } else {
    548             addr += 8;
    549         }
    550     }
    551     return 0;
    552 }
    553 
    554 static ssize_t mcf_fec_receive(NetClientState *nc, const uint8_t *buf, size_t size)
    555 {
    556     mcf_fec_state *s = qemu_get_nic_opaque(nc);
    557     mcf_fec_bd bd;
    558     uint32_t flags = 0;
    559     uint32_t addr;
    560     uint32_t crc;
    561     uint32_t buf_addr;
    562     uint8_t *crc_ptr;
    563     unsigned int buf_len;
    564     size_t retsize;
    565 
    566     DPRINTF("do_rx len %d\n", size);
    567     if (!s->rx_enabled) {
    568         return -1;
    569     }
    570     /* 4 bytes for the CRC.  */
    571     size += 4;
    572     crc = cpu_to_be32(crc32(~0, buf, size));
    573     crc_ptr = (uint8_t *)&crc;
    574     /* Huge frames are truncted.  */
    575     if (size > FEC_MAX_FRAME_SIZE) {
    576         size = FEC_MAX_FRAME_SIZE;
    577         flags |= FEC_BD_TR | FEC_BD_LG;
    578     }
    579     /* Frames larger than the user limit just set error flags.  */
    580     if (size > (s->rcr >> 16)) {
    581         flags |= FEC_BD_LG;
    582     }
    583     /* Check if we have enough space in current descriptors */
    584     if (!mcf_fec_have_receive_space(s, size)) {
    585         return 0;
    586     }
    587     addr = s->rx_descriptor;
    588     retsize = size;
    589     while (size > 0) {
    590         mcf_fec_read_bd(&bd, addr);
    591         buf_len = (size <= s->emrbr) ? size: s->emrbr;
    592         bd.length = buf_len;
    593         size -= buf_len;
    594         DPRINTF("rx_bd %x length %d\n", addr, bd.length);
    595         /* The last 4 bytes are the CRC.  */
    596         if (size < 4)
    597             buf_len += size - 4;
    598         buf_addr = bd.data;
    599         cpu_physical_memory_write(buf_addr, buf, buf_len);
    600         buf += buf_len;
    601         if (size < 4) {
    602             cpu_physical_memory_write(buf_addr + buf_len, crc_ptr, 4 - size);
    603             crc_ptr += 4 - size;
    604         }
    605         bd.flags &= ~FEC_BD_E;
    606         if (size == 0) {
    607             /* Last buffer in frame.  */
    608             bd.flags |= flags | FEC_BD_L;
    609             DPRINTF("rx frame flags %04x\n", bd.flags);
    610             s->eir |= FEC_INT_RXF;
    611         } else {
    612             s->eir |= FEC_INT_RXB;
    613         }
    614         mcf_fec_write_bd(&bd, addr);
    615         /* Advance to the next descriptor.  */
    616         if ((bd.flags & FEC_BD_W) != 0) {
    617             addr = s->erdsr;
    618         } else {
    619             addr += 8;
    620         }
    621     }
    622     s->rx_descriptor = addr;
    623     mcf_fec_rx_stats(s, retsize);
    624     mcf_fec_enable_rx(s);
    625     mcf_fec_update(s);
    626     return retsize;
    627 }
    628 
    629 static const MemoryRegionOps mcf_fec_ops = {
    630     .read = mcf_fec_read,
    631     .write = mcf_fec_write,
    632     .endianness = DEVICE_NATIVE_ENDIAN,
    633 };
    634 
    635 static NetClientInfo net_mcf_fec_info = {
    636     .type = NET_CLIENT_DRIVER_NIC,
    637     .size = sizeof(NICState),
    638     .receive = mcf_fec_receive,
    639 };
    640 
    641 static void mcf_fec_realize(DeviceState *dev, Error **errp)
    642 {
    643     mcf_fec_state *s = MCF_FEC_NET(dev);
    644 
    645     s->nic = qemu_new_nic(&net_mcf_fec_info, &s->conf,
    646                           object_get_typename(OBJECT(dev)), dev->id, s);
    647     qemu_format_nic_info_str(qemu_get_queue(s->nic), s->conf.macaddr.a);
    648 }
    649 
    650 static void mcf_fec_instance_init(Object *obj)
    651 {
    652     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
    653     mcf_fec_state *s = MCF_FEC_NET(obj);
    654     int i;
    655 
    656     memory_region_init_io(&s->iomem, obj, &mcf_fec_ops, s, "fec", 0x400);
    657     sysbus_init_mmio(sbd, &s->iomem);
    658     for (i = 0; i < FEC_NUM_IRQ; i++) {
    659         sysbus_init_irq(sbd, &s->irq[i]);
    660     }
    661 }
    662 
    663 static Property mcf_fec_properties[] = {
    664     DEFINE_NIC_PROPERTIES(mcf_fec_state, conf),
    665     DEFINE_PROP_END_OF_LIST(),
    666 };
    667 
    668 static void mcf_fec_class_init(ObjectClass *oc, void *data)
    669 {
    670     DeviceClass *dc = DEVICE_CLASS(oc);
    671 
    672     set_bit(DEVICE_CATEGORY_NETWORK, dc->categories);
    673     dc->realize = mcf_fec_realize;
    674     dc->desc = "MCF Fast Ethernet Controller network device";
    675     dc->reset = mcf_fec_reset;
    676     device_class_set_props(dc, mcf_fec_properties);
    677 }
    678 
    679 static const TypeInfo mcf_fec_info = {
    680     .name          = TYPE_MCF_FEC_NET,
    681     .parent        = TYPE_SYS_BUS_DEVICE,
    682     .instance_size = sizeof(mcf_fec_state),
    683     .instance_init = mcf_fec_instance_init,
    684     .class_init    = mcf_fec_class_init,
    685 };
    686 
    687 static void mcf_fec_register_types(void)
    688 {
    689     type_register_static(&mcf_fec_info);
    690 }
    691 
    692 type_init(mcf_fec_register_types)