pcnet.c

xen 3.2.2 源码

    if (CSR_DRX(s) || CSR_STOP(s) || CSR_SPND(s) || !size)
        return;

#ifdef PCNET_DEBUG
    printf("pcnet_receive size=%d\n", size);
#endif

    /* if too small buffer, then expand it */
    if (size < MIN_BUF_SIZE) {
        memcpy(buf1, buf, size);
        memset(buf1 + size, 0, MIN_BUF_SIZE - size);
        buf = buf1;
        size = MIN_BUF_SIZE;
    }

    if (CSR_PROM(s) 
        || (is_padr=padr_match(s, buf, size)) 
        || (is_bcast=padr_bcast(s, buf, size))
        || (is_ladr=ladr_match(s, buf, size))) {

        pcnet_rdte_poll(s);

        if (!(CSR_CRST(s) & 0x8000) && s->rdra) {
            struct pcnet_RMD rmd;
            int rcvrc = CSR_RCVRC(s)-1,i;
            target_phys_addr_t nrda;
            for (i = CSR_RCVRL(s)-1; i > 0; i--, rcvrc--) {
                if (rcvrc <= 1)
                    rcvrc = CSR_RCVRL(s);
                nrda = s->rdra +
                    (CSR_RCVRL(s) - rcvrc) *
                    (BCR_SWSTYLE(s) ? 16 : 8 );
                RMDLOAD(&rmd, PHYSADDR(s,nrda));                  
                if (rmd.rmd1.own) {                
#ifdef PCNET_DEBUG_RMD
                    printf("pcnet - scan buffer: RCVRC=%d PREV_RCVRC=%d\n", 
                                rcvrc, CSR_RCVRC(s));
#endif
                    CSR_RCVRC(s) = rcvrc;
                    pcnet_rdte_poll(s);
                    break;
                }
            }
        }

        if (!(CSR_CRST(s) & 0x8000)) {
#ifdef PCNET_DEBUG_RMD
            printf("pcnet - no buffer: RCVRC=%d\n", CSR_RCVRC(s));
#endif
            s->csr[0] |= 0x1000; /* Set MISS flag */
            CSR_MISSC(s)++;
        } else {
            uint8_t *src = &s->buffer[8];
            target_phys_addr_t crda = CSR_CRDA(s);
            struct pcnet_RMD rmd;
            int pktcount = 0;

            memcpy(src, buf, size);
            
#if 1
            /* no need to compute the CRC */
            src[size] = 0;
            src[size + 1] = 0;
            src[size + 2] = 0;
            src[size + 3] = 0;
            size += 4;
#else
            /* XXX: avoid CRC generation */
            if (!CSR_ASTRP_RCV(s)) {
                uint32_t fcs = ~0;
                uint8_t *p = src;

                while (size < 46) {
                    src[size++] = 0;
                }
                
                while (p != &src[size]) {
                    CRC(fcs, *p++);
                }
                ((uint32_t *)&src[size])[0] = htonl(fcs);
                size += 4; /* FCS at end of packet */
            } else size += 4;
#endif

#ifdef PCNET_DEBUG_MATCH
            PRINT_PKTHDR(buf);
#endif

            RMDLOAD(&rmd, PHYSADDR(s,crda));
            /*if (!CSR_LAPPEN(s))*/
                rmd.rmd1.stp = 1;

#define PCNET_RECV_STORE() do {                                 \
    int count = MIN(4096 - rmd.rmd1.bcnt,size);                 \
    target_phys_addr_t rbadr = PHYSADDR(s, rmd.rmd0.rbadr);     \
    s->phys_mem_write(s->dma_opaque, rbadr, src, count, CSR_BSWP(s));  \
    src += count; size -= count;                                \
    rmd.rmd2.mcnt = count; rmd.rmd1.own = 0;                    \
    RMDSTORE(&rmd, PHYSADDR(s,crda));                           \
    pktcount++;                                                 \
} while (0)

            PCNET_RECV_STORE();
            if ((size > 0) && CSR_NRDA(s)) {
                target_phys_addr_t nrda = CSR_NRDA(s);
                RMDLOAD(&rmd, PHYSADDR(s,nrda));
                if (rmd.rmd1.own) {
                    crda = nrda;
                    PCNET_RECV_STORE();
                    if ((size > 0) && (nrda=CSR_NNRD(s))) {
                        RMDLOAD(&rmd, PHYSADDR(s,nrda));
                        if (rmd.rmd1.own) {
                            crda = nrda;
                            PCNET_RECV_STORE();
                        }
                    }
                }                
            }

#undef PCNET_RECV_STORE

            RMDLOAD(&rmd, PHYSADDR(s,crda));
            if (size == 0) {
                rmd.rmd1.enp = 1;
                rmd.rmd1.pam = !CSR_PROM(s) && is_padr;
                rmd.rmd1.lafm = !CSR_PROM(s) && is_ladr;
                rmd.rmd1.bam = !CSR_PROM(s) && is_bcast;
            } else {
                rmd.rmd1.oflo = 1;
                rmd.rmd1.buff = 1;
                rmd.rmd1.err = 1;
            }
            RMDSTORE(&rmd, PHYSADDR(s,crda));
            s->csr[0] |= 0x0400;

#ifdef PCNET_DEBUG
            printf("RCVRC=%d CRDA=0x%08x BLKS=%d\n", 
                CSR_RCVRC(s), PHYSADDR(s,CSR_CRDA(s)), pktcount);
#endif
#ifdef PCNET_DEBUG_RMD
            PRINT_RMD(&rmd);
#endif        

            while (pktcount--) {
                if (CSR_RCVRC(s) <= 1)
                    CSR_RCVRC(s) = CSR_RCVRL(s);
                else
                    CSR_RCVRC(s)--;            
            }
            
            pcnet_rdte_poll(s);

        }        
    }

    pcnet_poll(s);
    pcnet_update_irq(s);    
}

static void pcnet_transmit(PCNetState *s)
{
    target_phys_addr_t xmit_cxda = 0;
    int count = CSR_XMTRL(s)-1;
    s->xmit_pos = -1;
    
    if (!CSR_TXON(s)) {
        s->csr[0] &= ~0x0008;
        return;
    }

    s->tx_busy = 1;

    txagain:
    if (pcnet_tdte_poll(s)) {
        struct pcnet_TMD tmd;

        TMDLOAD(&tmd, PHYSADDR(s,CSR_CXDA(s)));                

#ifdef PCNET_DEBUG_TMD
        printf("  TMDLOAD 0x%08x\n", PHYSADDR(s,CSR_CXDA(s)));
        PRINT_TMD(&tmd);
#endif
        if (tmd.tmd1.stp) {
            s->xmit_pos = 0;                
            if (!tmd.tmd1.enp) {
                s->phys_mem_read(s->dma_opaque, PHYSADDR(s, tmd.tmd0.tbadr),
                                 s->buffer, 4096 - tmd.tmd1.bcnt, 
                                 CSR_BSWP(s));
                s->xmit_pos += 4096 - tmd.tmd1.bcnt;
            } 
            xmit_cxda = PHYSADDR(s,CSR_CXDA(s));
        }
        if (tmd.tmd1.enp && (s->xmit_pos >= 0)) {
            s->phys_mem_read(s->dma_opaque, PHYSADDR(s, tmd.tmd0.tbadr),
                             s->buffer + s->xmit_pos, 4096 - tmd.tmd1.bcnt, 
                             CSR_BSWP(s));
            s->xmit_pos += 4096 - tmd.tmd1.bcnt;
#ifdef PCNET_DEBUG
            printf("pcnet_transmit size=%d\n", s->xmit_pos);
#endif            
            if (CSR_LOOP(s))
                pcnet_receive(s, s->buffer, s->xmit_pos);
            else
                qemu_send_packet(s->vc, s->buffer, s->xmit_pos);

            s->csr[0] &= ~0x0008;   /* clear TDMD */
            s->csr[4] |= 0x0004;    /* set TXSTRT */
            s->xmit_pos = -1;
        }

        tmd.tmd1.own = 0;
        TMDSTORE(&tmd, PHYSADDR(s,CSR_CXDA(s)));
        if (!CSR_TOKINTD(s) || (CSR_LTINTEN(s) && tmd.tmd1.ltint))
            s->csr[0] |= 0x0200;    /* set TINT */

        if (CSR_XMTRC(s)<=1)
            CSR_XMTRC(s) = CSR_XMTRL(s);
        else
            CSR_XMTRC(s)--;
        if (count--)
            goto txagain;

    } else 
    if (s->xmit_pos >= 0) {
        struct pcnet_TMD tmd;
        TMDLOAD(&tmd, PHYSADDR(s,xmit_cxda));                
        tmd.tmd2.buff = tmd.tmd2.uflo = tmd.tmd1.err = 1;
        tmd.tmd1.own = 0;
        TMDSTORE(&tmd, PHYSADDR(s,xmit_cxda));
        s->csr[0] |= 0x0200;    /* set TINT */
        if (!CSR_DXSUFLO(s)) {
            s->csr[0] &= ~0x0010;
        } else
        if (count--)
          goto txagain;
    }

    s->tx_busy = 0;
}

static void pcnet_poll(PCNetState *s)
{
    if (CSR_RXON(s)) {
        pcnet_rdte_poll(s);
    }

    if (CSR_TDMD(s) || 
        (CSR_TXON(s) && !CSR_DPOLL(s) && pcnet_tdte_poll(s)))
    {
        /* prevent recursion */
        if (s->tx_busy)
            return;

        pcnet_transmit(s);
    }
}

static void pcnet_poll_timer(void *opaque)
{
    PCNetState *s = opaque;

    qemu_del_timer(s->poll_timer);

    if (CSR_TDMD(s)) {
        pcnet_transmit(s);
    }

    pcnet_update_irq(s);    

    if (!CSR_STOP(s) && !CSR_SPND(s) && !CSR_DPOLL(s)) {
        uint64_t now = qemu_get_clock(vm_clock) * 33;
        if (!s->timer || !now)
            s->timer = now;
        else {
            uint64_t t = now - s->timer + CSR_POLL(s);
            if (t > 0xffffLL) {
                pcnet_poll(s);
                CSR_POLL(s) = CSR_PINT(s);
            } else
                CSR_POLL(s) = t;
        }
        qemu_mod_timer(s->poll_timer, 
            pcnet_get_next_poll_time(s,qemu_get_clock(vm_clock)));
    }
}


static void pcnet_csr_writew(PCNetState *s, uint32_t rap, uint32_t new_value)
{
    uint16_t val = new_value;
#ifdef PCNET_DEBUG_CSR
    printf("pcnet_csr_writew rap=%d val=0x%04x\n", rap, val);
#endif
    switch (rap) {
    case 0:
        s->csr[0] &= ~(val & 0x7f00); /* Clear any interrupt flags */

        s->csr[0] = (s->csr[0] & ~0x0040) | (val & 0x0048);

        val = (val & 0x007f) | (s->csr[0] & 0x7f00);

        /* IFF STOP, STRT and INIT are set, clear STRT and INIT */
        if ((val&7) == 7)
          val &= ~3;

        if (!CSR_STOP(s) && (val & 4))
            pcnet_stop(s);

        if (!CSR_INIT(s) && (val & 1))
            pcnet_init(s);

        if (!CSR_STRT(s) && (val & 2))
            pcnet_start(s);

        if (CSR_TDMD(s)) 
            pcnet_transmit(s);

        return;
    case 1:
    case 2:
    case 8:
    case 9:
    case 10:
    case 11:
    case 12:
    case 13:
    case 14:
    case 15:
    case 18: /* CRBAL */
    case 19: /* CRBAU */
    case 20: /* CXBAL */
    case 21: /* CXBAU */
    case 22: /* NRBAU */
    case 23: /* NRBAU */
    case 24:
    case 25:
    case 26:
    case 27:
    case 28:
    case 29:
    case 30:
    case 31:
    case 32:
    case 33:
    case 34:
    case 35:
    case 36:
    case 37:
    case 38:
    case 39:
    case 40: /* CRBC */
    case 41:
    case 42: /* CXBC */
    case 43:
    case 44:
    case 45:
    case 46: /* POLL */
    case 47: /* POLLINT */
    case 72:
    case 74:
    case 76: /* RCVRL */
    case 78: /* XMTRL */
    case 112:
       if (CSR_STOP(s) || CSR_SPND(s))
           break;
       return;
    case 3:
        break;
    case 4:
        s->csr[4] &= ~(val & 0x026a); 
        val &= ~0x026a; val |= s->csr[4] & 0x026a;
        break;
    case 5:
        s->csr[5] &= ~(val & 0x0a90); 
        val &= ~0x0a90; val |= s->csr[5] & 0x0a90;
        break;
    case 16:
        pcnet_csr_writew(s,1,val);
        return;
    case 17:
        pcnet_csr_writew(s,2,val);
        return;
    case 58:
        pcnet_bcr_writew(s,BCR_SWS,val);
        break;
    default:
        return;
    }
    s->csr[rap] = val;
}

static uint32_t pcnet_csr_readw(PCNetState *s, uint32_t rap)
{
    uint32_t val;
    switch (rap) {
    case 0:
        pcnet_update_irq(s);
        val = s->csr[0];
        val |= (val & 0x7800) ? 0x8000 : 0;
        break;
    case 16:
        return pcnet_csr_readw(s,1);
    case 17:
        return pcnet_csr_readw(s,2);
    case 58:
        return pcnet_bcr_readw(s,BCR_SWS);
    case 88:
        val = s->csr[89];
        val <<= 16;
        val |= s->csr[88];
        break;
    default:
        val = s->csr[rap];
    }
#ifdef PCNET_DEBUG_CSR
    printf("pcnet_csr_readw rap=%d val=0x%04x\n", rap, val);
#endif
    return val;
}

static void pcnet_bcr_writew(PCNetState *s, uint32_t rap, uint32_t val)
{
    rap &= 127;
#ifdef PCNET_DEBUG_BCR
    printf("pcnet_bcr_writew rap=%d val=0x%04x\n", rap, val);
#endif
    switch (rap) {
    case BCR_SWS:
        if (!(CSR_STOP(s) || CSR_SPND(s)))
            return;
        val &= ~0x0300;
        switch (val & 0x00ff) {
        case 0:
            val |= 0x0200;
            break;
        case 1:
            val |= 0x0100;
            break;
        case 2:
        case 3:
            val |= 0x0300;
            break;
        default:
            printf("Bad SWSTYLE=0x%02x\n", val & 0xff);
            val = 0x0200;
            break;
        }
#ifdef PCNET_DEBUG
       printf("BCR_SWS=0x%04x\n", val);
#endif
    case BCR_LNKST:
    case BCR_LED1:
    case BCR_LED2:
    case BCR_LED3:
    case BCR_MC:
    case BCR_FDC:
    case BCR_BSBC:
    case BCR_EECAS:
    case BCR_PLAT:
        s->bcr[rap] = val;
        break;
    default:
        break;
    }
}

static uint32_t pcnet_bcr_readw(PCNetState *s, uint32_t rap)
{
    uint32_t val;
    rap &= 127;
    switch (rap) {
    case BCR_LNKST:
    case BCR_LED1:
    case BCR_LED2:
    case BCR_LED3:
        val = s->bcr[rap] & ~0x8000;
        val |= (val & 0x017f & s->lnkst) ? 0x8000 : 0;
        break;
    default:
        val = rap < 32 ? s->bcr[rap] : 0;
        break;
    }
#ifdef PCNET_DEBUG_BCR
    printf("pcnet_bcr_readw rap=%d val=0x%04x\n", rap, val);
#endif
    return val;
}

void pcnet_h_reset(void *opaque)
{
    PCNetState *s = opaque;
    int i;
    uint16_t checksum;

    /* Initialize the PROM */

    memcpy(s->prom, s->nd->macaddr, 6);
    s->prom[12] = s->prom[13] = 0x00;
    s->prom[14] = s->prom[15] = 0x57;