xref: /qemu/hw/net/ne2000.c (revision 8b7b9c5c)
1 /*
2  * QEMU NE2000 emulation
3  *
4  * Copyright (c) 2003-2004 Fabrice Bellard
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 #include "qemu/osdep.h"
26 #include "net/eth.h"
27 #include "qemu/module.h"
28 #include "exec/memory.h"
29 #include "hw/irq.h"
30 #include "migration/vmstate.h"
31 #include "ne2000.h"
32 #include "trace.h"
33 
34 /* debug NE2000 card */
35 //#define DEBUG_NE2000
36 
37 #define MAX_ETH_FRAME_SIZE 1514
38 
39 #define E8390_CMD       0x00    /* The command register (for all pages) */
40 /* Page 0 register offsets. */
41 #define EN0_CLDALO      0x01    /* Low byte of current local dma addr  RD */
42 #define EN0_STARTPG     0x01    /* Starting page of ring bfr WR */
43 #define EN0_CLDAHI      0x02    /* High byte of current local dma addr  RD */
44 #define EN0_STOPPG      0x02    /* Ending page +1 of ring bfr WR */
45 #define EN0_BOUNDARY    0x03    /* Boundary page of ring bfr RD WR */
46 #define EN0_TSR         0x04    /* Transmit status reg RD */
47 #define EN0_TPSR        0x04    /* Transmit starting page WR */
48 #define EN0_NCR         0x05    /* Number of collision reg RD */
49 #define EN0_TCNTLO      0x05    /* Low  byte of tx byte count WR */
50 #define EN0_FIFO        0x06    /* FIFO RD */
51 #define EN0_TCNTHI      0x06    /* High byte of tx byte count WR */
52 #define EN0_ISR         0x07    /* Interrupt status reg RD WR */
53 #define EN0_CRDALO      0x08    /* low byte of current remote dma address RD */
54 #define EN0_RSARLO      0x08    /* Remote start address reg 0 */
55 #define EN0_CRDAHI      0x09    /* high byte, current remote dma address RD */
56 #define EN0_RSARHI      0x09    /* Remote start address reg 1 */
57 #define EN0_RCNTLO      0x0a    /* Remote byte count reg WR */
58 #define EN0_RTL8029ID0  0x0a    /* Realtek ID byte #1 RD */
59 #define EN0_RCNTHI      0x0b    /* Remote byte count reg WR */
60 #define EN0_RTL8029ID1  0x0b    /* Realtek ID byte #2 RD */
61 #define EN0_RSR         0x0c    /* rx status reg RD */
62 #define EN0_RXCR        0x0c    /* RX configuration reg WR */
63 #define EN0_TXCR        0x0d    /* TX configuration reg WR */
64 #define EN0_COUNTER0    0x0d    /* Rcv alignment error counter RD */
65 #define EN0_DCFG        0x0e    /* Data configuration reg WR */
66 #define EN0_COUNTER1    0x0e    /* Rcv CRC error counter RD */
67 #define EN0_IMR         0x0f    /* Interrupt mask reg WR */
68 #define EN0_COUNTER2    0x0f    /* Rcv missed frame error counter RD */
69 
70 #define EN1_PHYS        0x11
71 #define EN1_CURPAG      0x17
72 #define EN1_MULT        0x18
73 
74 #define EN2_STARTPG     0x21    /* Starting page of ring bfr RD */
75 #define EN2_STOPPG      0x22    /* Ending page +1 of ring bfr RD */
76 
77 #define EN3_CONFIG0     0x33
78 #define EN3_CONFIG1     0x34
79 #define EN3_CONFIG2     0x35
80 #define EN3_CONFIG3     0x36
81 
82 /*  Register accessed at EN_CMD, the 8390 base addr.  */
83 #define E8390_STOP      0x01    /* Stop and reset the chip */
84 #define E8390_START     0x02    /* Start the chip, clear reset */
85 #define E8390_TRANS     0x04    /* Transmit a frame */
86 #define E8390_RREAD     0x08    /* Remote read */
87 #define E8390_RWRITE    0x10    /* Remote write  */
88 #define E8390_NODMA     0x20    /* Remote DMA */
89 #define E8390_PAGE0     0x00    /* Select page chip registers */
90 #define E8390_PAGE1     0x40    /* using the two high-order bits */
91 #define E8390_PAGE2     0x80    /* Page 3 is invalid. */
92 
93 /* Bits in EN0_ISR - Interrupt status register */
94 #define ENISR_RX        0x01    /* Receiver, no error */
95 #define ENISR_TX        0x02    /* Transmitter, no error */
96 #define ENISR_RX_ERR    0x04    /* Receiver, with error */
97 #define ENISR_TX_ERR    0x08    /* Transmitter, with error */
98 #define ENISR_OVER      0x10    /* Receiver overwrote the ring */
99 #define ENISR_COUNTERS  0x20    /* Counters need emptying */
100 #define ENISR_RDC       0x40    /* remote dma complete */
101 #define ENISR_RESET     0x80    /* Reset completed */
102 #define ENISR_ALL       0x3f    /* Interrupts we will enable */
103 
104 /* Bits in received packet status byte and EN0_RSR*/
105 #define ENRSR_RXOK      0x01    /* Received a good packet */
106 #define ENRSR_CRC       0x02    /* CRC error */
107 #define ENRSR_FAE       0x04    /* frame alignment error */
108 #define ENRSR_FO        0x08    /* FIFO overrun */
109 #define ENRSR_MPA       0x10    /* missed pkt */
110 #define ENRSR_PHY       0x20    /* physical/multicast address */
111 #define ENRSR_DIS       0x40    /* receiver disable. set in monitor mode */
112 #define ENRSR_DEF       0x80    /* deferring */
113 
114 /* Transmitted packet status, EN0_TSR. */
115 #define ENTSR_PTX 0x01  /* Packet transmitted without error */
116 #define ENTSR_ND  0x02  /* The transmit wasn't deferred. */
117 #define ENTSR_COL 0x04  /* The transmit collided at least once. */
118 #define ENTSR_ABT 0x08  /* The transmit collided 16 times, and was deferred. */
119 #define ENTSR_CRS 0x10  /* The carrier sense was lost. */
120 #define ENTSR_FU  0x20  /* A "FIFO underrun" occurred during transmit. */
121 #define ENTSR_CDH 0x40  /* The collision detect "heartbeat" signal was lost. */
122 #define ENTSR_OWC 0x80  /* There was an out-of-window collision. */
123 
124 void ne2000_reset(NE2000State *s)
125 {
126     int i;
127 
128     s->isr = ENISR_RESET;
129     memcpy(s->mem, &s->c.macaddr, 6);
130     s->mem[14] = 0x57;
131     s->mem[15] = 0x57;
132 
133     /* duplicate prom data */
134     for(i = 15;i >= 0; i--) {
135         s->mem[2 * i] = s->mem[i];
136         s->mem[2 * i + 1] = s->mem[i];
137     }
138 }
139 
140 static void ne2000_update_irq(NE2000State *s)
141 {
142     int isr;
143     isr = (s->isr & s->imr) & 0x7f;
144 #if defined(DEBUG_NE2000)
145     printf("NE2000: Set IRQ to %d (%02x %02x)\n",
146            isr ? 1 : 0, s->isr, s->imr);
147 #endif
148     qemu_set_irq(s->irq, (isr != 0));
149 }
150 
151 static int ne2000_buffer_full(NE2000State *s)
152 {
153     int avail, index, boundary;
154 
155     if (s->stop <= s->start) {
156         return 1;
157     }
158 
159     index = s->curpag << 8;
160     boundary = s->boundary << 8;
161     if (index < boundary)
162         avail = boundary - index;
163     else
164         avail = (s->stop - s->start) - (index - boundary);
165     if (avail < (MAX_ETH_FRAME_SIZE + 4))
166         return 1;
167     return 0;
168 }
169 
170 ssize_t ne2000_receive(NetClientState *nc, const uint8_t *buf, size_t size_)
171 {
172     NE2000State *s = qemu_get_nic_opaque(nc);
173     size_t size = size_;
174     uint8_t *p;
175     unsigned int total_len, next, avail, len, index, mcast_idx;
176     static const uint8_t broadcast_macaddr[6] =
177         { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
178 
179 #if defined(DEBUG_NE2000)
180     printf("NE2000: received len=%zu\n", size);
181 #endif
182 
183     if (s->cmd & E8390_STOP || ne2000_buffer_full(s))
184         return -1;
185 
186     /* XXX: check this */
187     if (s->rxcr & 0x10) {
188         /* promiscuous: receive all */
189     } else {
190         if (!memcmp(buf,  broadcast_macaddr, 6)) {
191             /* broadcast address */
192             if (!(s->rxcr & 0x04))
193                 return size;
194         } else if (buf[0] & 0x01) {
195             /* multicast */
196             if (!(s->rxcr & 0x08))
197                 return size;
198             mcast_idx = net_crc32(buf, ETH_ALEN) >> 26;
199             if (!(s->mult[mcast_idx >> 3] & (1 << (mcast_idx & 7))))
200                 return size;
201         } else if (s->mem[0] == buf[0] &&
202                    s->mem[2] == buf[1] &&
203                    s->mem[4] == buf[2] &&
204                    s->mem[6] == buf[3] &&
205                    s->mem[8] == buf[4] &&
206                    s->mem[10] == buf[5]) {
207             /* match */
208         } else {
209             return size;
210         }
211     }
212 
213     index = s->curpag << 8;
214     if (index >= NE2000_PMEM_END) {
215         index = s->start;
216     }
217     /* 4 bytes for header */
218     total_len = size + 4;
219     /* address for next packet (4 bytes for CRC) */
220     next = index + ((total_len + 4 + 255) & ~0xff);
221     if (next >= s->stop)
222         next -= (s->stop - s->start);
223     /* prepare packet header */
224     p = s->mem + index;
225     s->rsr = ENRSR_RXOK; /* receive status */
226     /* XXX: check this */
227     if (buf[0] & 0x01)
228         s->rsr |= ENRSR_PHY;
229     p[0] = s->rsr;
230     p[1] = next >> 8;
231     p[2] = total_len;
232     p[3] = total_len >> 8;
233     index += 4;
234 
235     /* write packet data */
236     while (size > 0) {
237         if (index <= s->stop)
238             avail = s->stop - index;
239         else
240             break;
241         len = size;
242         if (len > avail)
243             len = avail;
244         memcpy(s->mem + index, buf, len);
245         buf += len;
246         index += len;
247         if (index == s->stop)
248             index = s->start;
249         size -= len;
250     }
251     s->curpag = next >> 8;
252 
253     /* now we can signal we have received something */
254     s->isr |= ENISR_RX;
255     ne2000_update_irq(s);
256 
257     return size_;
258 }
259 
260 static void ne2000_ioport_write(void *opaque, uint32_t addr, uint32_t val)
261 {
262     NE2000State *s = opaque;
263     int offset, page, index;
264 
265     addr &= 0xf;
266     trace_ne2000_ioport_write(addr, val);
267     if (addr == E8390_CMD) {
268         /* control register */
269         s->cmd = val;
270         if (!(val & E8390_STOP)) { /* START bit makes no sense on RTL8029... */
271             s->isr &= ~ENISR_RESET;
272             /* test specific case: zero length transfer */
273             if ((val & (E8390_RREAD | E8390_RWRITE)) &&
274                 s->rcnt == 0) {
275                 s->isr |= ENISR_RDC;
276                 ne2000_update_irq(s);
277             }
278             if (val & E8390_TRANS) {
279                 index = (s->tpsr << 8);
280                 /* XXX: next 2 lines are a hack to make netware 3.11 work */
281                 if (index >= NE2000_PMEM_END)
282                     index -= NE2000_PMEM_SIZE;
283                 /* fail safe: check range on the transmitted length  */
284                 if (index + s->tcnt <= NE2000_PMEM_END) {
285                     qemu_send_packet(qemu_get_queue(s->nic), s->mem + index,
286                                      s->tcnt);
287                 }
288                 /* signal end of transfer */
289                 s->tsr = ENTSR_PTX;
290                 s->isr |= ENISR_TX;
291                 s->cmd &= ~E8390_TRANS;
292                 ne2000_update_irq(s);
293             }
294         }
295     } else {
296         page = s->cmd >> 6;
297         offset = addr | (page << 4);
298         switch(offset) {
299         case EN0_STARTPG:
300             if (val << 8 <= NE2000_PMEM_END) {
301                 s->start = val << 8;
302             }
303             break;
304         case EN0_STOPPG:
305             if (val << 8 <= NE2000_PMEM_END) {
306                 s->stop = val << 8;
307             }
308             break;
309         case EN0_BOUNDARY:
310             if (val << 8 < NE2000_PMEM_END) {
311                 s->boundary = val;
312             }
313             break;
314         case EN0_IMR:
315             s->imr = val;
316             ne2000_update_irq(s);
317             break;
318         case EN0_TPSR:
319             s->tpsr = val;
320             break;
321         case EN0_TCNTLO:
322             s->tcnt = (s->tcnt & 0xff00) | val;
323             break;
324         case EN0_TCNTHI:
325             s->tcnt = (s->tcnt & 0x00ff) | (val << 8);
326             break;
327         case EN0_RSARLO:
328             s->rsar = (s->rsar & 0xff00) | val;
329             break;
330         case EN0_RSARHI:
331             s->rsar = (s->rsar & 0x00ff) | (val << 8);
332             break;
333         case EN0_RCNTLO:
334             s->rcnt = (s->rcnt & 0xff00) | val;
335             break;
336         case EN0_RCNTHI:
337             s->rcnt = (s->rcnt & 0x00ff) | (val << 8);
338             break;
339         case EN0_RXCR:
340             s->rxcr = val;
341             break;
342         case EN0_DCFG:
343             s->dcfg = val;
344             break;
345         case EN0_ISR:
346             s->isr &= ~(val & 0x7f);
347             ne2000_update_irq(s);
348             break;
349         case EN1_PHYS ... EN1_PHYS + 5:
350             s->phys[offset - EN1_PHYS] = val;
351             break;
352         case EN1_CURPAG:
353             if (val << 8 < NE2000_PMEM_END) {
354                 s->curpag = val;
355             }
356             break;
357         case EN1_MULT ... EN1_MULT + 7:
358             s->mult[offset - EN1_MULT] = val;
359             break;
360         }
361     }
362 }
363 
364 static uint32_t ne2000_ioport_read(void *opaque, uint32_t addr)
365 {
366     NE2000State *s = opaque;
367     int offset, page, ret;
368 
369     addr &= 0xf;
370     if (addr == E8390_CMD) {
371         ret = s->cmd;
372     } else {
373         page = s->cmd >> 6;
374         offset = addr | (page << 4);
375         switch(offset) {
376         case EN0_TSR:
377             ret = s->tsr;
378             break;
379         case EN0_BOUNDARY:
380             ret = s->boundary;
381             break;
382         case EN0_ISR:
383             ret = s->isr;
384             break;
385         case EN0_RSARLO:
386             ret = s->rsar & 0x00ff;
387             break;
388         case EN0_RSARHI:
389             ret = s->rsar >> 8;
390             break;
391         case EN1_PHYS ... EN1_PHYS + 5:
392             ret = s->phys[offset - EN1_PHYS];
393             break;
394         case EN1_CURPAG:
395             ret = s->curpag;
396             break;
397         case EN1_MULT ... EN1_MULT + 7:
398             ret = s->mult[offset - EN1_MULT];
399             break;
400         case EN0_RSR:
401             ret = s->rsr;
402             break;
403         case EN2_STARTPG:
404             ret = s->start >> 8;
405             break;
406         case EN2_STOPPG:
407             ret = s->stop >> 8;
408             break;
409         case EN0_RTL8029ID0:
410             ret = 0x50;
411             break;
412         case EN0_RTL8029ID1:
413             ret = 0x43;
414             break;
415         case EN3_CONFIG0:
416             ret = 0;          /* 10baseT media */
417             break;
418         case EN3_CONFIG2:
419             ret = 0x40;       /* 10baseT active */
420             break;
421         case EN3_CONFIG3:
422             ret = 0x40;       /* Full duplex */
423             break;
424         default:
425             ret = 0x00;
426             break;
427         }
428     }
429     trace_ne2000_ioport_read(addr, ret);
430     return ret;
431 }
432 
433 static inline void ne2000_mem_writeb(NE2000State *s, uint32_t addr,
434                                      uint32_t val)
435 {
436     if (addr < 32 ||
437         (addr >= NE2000_PMEM_START && addr < NE2000_MEM_SIZE)) {
438         s->mem[addr] = val;
439     }
440 }
441 
442 static inline void ne2000_mem_writew(NE2000State *s, uint32_t addr,
443                                      uint32_t val)
444 {
445     addr &= ~1; /* XXX: check exact behaviour if not even */
446     if (addr < 32 ||
447         (addr >= NE2000_PMEM_START && addr < NE2000_MEM_SIZE)) {
448         *(uint16_t *)(s->mem + addr) = cpu_to_le16(val);
449     }
450 }
451 
452 static inline void ne2000_mem_writel(NE2000State *s, uint32_t addr,
453                                      uint32_t val)
454 {
455     addr &= ~1; /* XXX: check exact behaviour if not even */
456     if (addr < 32
457         || (addr >= NE2000_PMEM_START
458             && addr + sizeof(uint32_t) <= NE2000_MEM_SIZE)) {
459         stl_le_p(s->mem + addr, val);
460     }
461 }
462 
463 static inline uint32_t ne2000_mem_readb(NE2000State *s, uint32_t addr)
464 {
465     if (addr < 32 ||
466         (addr >= NE2000_PMEM_START && addr < NE2000_MEM_SIZE)) {
467         return s->mem[addr];
468     } else {
469         return 0xff;
470     }
471 }
472 
473 static inline uint32_t ne2000_mem_readw(NE2000State *s, uint32_t addr)
474 {
475     addr &= ~1; /* XXX: check exact behaviour if not even */
476     if (addr < 32 ||
477         (addr >= NE2000_PMEM_START && addr < NE2000_MEM_SIZE)) {
478         return le16_to_cpu(*(uint16_t *)(s->mem + addr));
479     } else {
480         return 0xffff;
481     }
482 }
483 
484 static inline uint32_t ne2000_mem_readl(NE2000State *s, uint32_t addr)
485 {
486     addr &= ~1; /* XXX: check exact behaviour if not even */
487     if (addr < 32
488         || (addr >= NE2000_PMEM_START
489             && addr + sizeof(uint32_t) <= NE2000_MEM_SIZE)) {
490         return ldl_le_p(s->mem + addr);
491     } else {
492         return 0xffffffff;
493     }
494 }
495 
496 static inline void ne2000_dma_update(NE2000State *s, int len)
497 {
498     s->rsar += len;
499     /* wrap */
500     /* XXX: check what to do if rsar > stop */
501     if (s->rsar == s->stop)
502         s->rsar = s->start;
503 
504     if (s->rcnt <= len) {
505         s->rcnt = 0;
506         /* signal end of transfer */
507         s->isr |= ENISR_RDC;
508         ne2000_update_irq(s);
509     } else {
510         s->rcnt -= len;
511     }
512 }
513 
514 static void ne2000_asic_ioport_write(void *opaque, uint32_t addr, uint32_t val)
515 {
516     NE2000State *s = opaque;
517 
518 #ifdef DEBUG_NE2000
519     printf("NE2000: asic write val=0x%04x\n", val);
520 #endif
521     if (s->rcnt == 0)
522         return;
523     if (s->dcfg & 0x01) {
524         /* 16 bit access */
525         ne2000_mem_writew(s, s->rsar, val);
526         ne2000_dma_update(s, 2);
527     } else {
528         /* 8 bit access */
529         ne2000_mem_writeb(s, s->rsar, val);
530         ne2000_dma_update(s, 1);
531     }
532 }
533 
534 static uint32_t ne2000_asic_ioport_read(void *opaque, uint32_t addr)
535 {
536     NE2000State *s = opaque;
537     int ret;
538 
539     if (s->dcfg & 0x01) {
540         /* 16 bit access */
541         ret = ne2000_mem_readw(s, s->rsar);
542         ne2000_dma_update(s, 2);
543     } else {
544         /* 8 bit access */
545         ret = ne2000_mem_readb(s, s->rsar);
546         ne2000_dma_update(s, 1);
547     }
548 #ifdef DEBUG_NE2000
549     printf("NE2000: asic read val=0x%04x\n", ret);
550 #endif
551     return ret;
552 }
553 
554 static void ne2000_asic_ioport_writel(void *opaque, uint32_t addr, uint32_t val)
555 {
556     NE2000State *s = opaque;
557 
558 #ifdef DEBUG_NE2000
559     printf("NE2000: asic writel val=0x%04x\n", val);
560 #endif
561     if (s->rcnt == 0)
562         return;
563     /* 32 bit access */
564     ne2000_mem_writel(s, s->rsar, val);
565     ne2000_dma_update(s, 4);
566 }
567 
568 static uint32_t ne2000_asic_ioport_readl(void *opaque, uint32_t addr)
569 {
570     NE2000State *s = opaque;
571     int ret;
572 
573     /* 32 bit access */
574     ret = ne2000_mem_readl(s, s->rsar);
575     ne2000_dma_update(s, 4);
576 #ifdef DEBUG_NE2000
577     printf("NE2000: asic readl val=0x%04x\n", ret);
578 #endif
579     return ret;
580 }
581 
582 static void ne2000_reset_ioport_write(void *opaque, uint32_t addr, uint32_t val)
583 {
584     /* nothing to do (end of reset pulse) */
585 }
586 
587 static uint32_t ne2000_reset_ioport_read(void *opaque, uint32_t addr)
588 {
589     NE2000State *s = opaque;
590     ne2000_reset(s);
591     return 0;
592 }
593 
594 static int ne2000_post_load(void* opaque, int version_id)
595 {
596     NE2000State* s = opaque;
597 
598     if (version_id < 2) {
599         s->rxcr = 0x0c;
600     }
601     return 0;
602 }
603 
604 const VMStateDescription vmstate_ne2000 = {
605     .name = "ne2000",
606     .version_id = 2,
607     .minimum_version_id = 0,
608     .post_load = ne2000_post_load,
609     .fields = (VMStateField[]) {
610         VMSTATE_UINT8_V(rxcr, NE2000State, 2),
611         VMSTATE_UINT8(cmd, NE2000State),
612         VMSTATE_UINT32(start, NE2000State),
613         VMSTATE_UINT32(stop, NE2000State),
614         VMSTATE_UINT8(boundary, NE2000State),
615         VMSTATE_UINT8(tsr, NE2000State),
616         VMSTATE_UINT8(tpsr, NE2000State),
617         VMSTATE_UINT16(tcnt, NE2000State),
618         VMSTATE_UINT16(rcnt, NE2000State),
619         VMSTATE_UINT32(rsar, NE2000State),
620         VMSTATE_UINT8(rsr, NE2000State),
621         VMSTATE_UINT8(isr, NE2000State),
622         VMSTATE_UINT8(dcfg, NE2000State),
623         VMSTATE_UINT8(imr, NE2000State),
624         VMSTATE_BUFFER(phys, NE2000State),
625         VMSTATE_UINT8(curpag, NE2000State),
626         VMSTATE_BUFFER(mult, NE2000State),
627         VMSTATE_UNUSED(4), /* was irq */
628         VMSTATE_BUFFER(mem, NE2000State),
629         VMSTATE_END_OF_LIST()
630     }
631 };
632 
633 static uint64_t ne2000_read(void *opaque, hwaddr addr,
634                             unsigned size)
635 {
636     NE2000State *s = opaque;
637     uint64_t val;
638 
639     if (addr < 0x10 && size == 1) {
640         val = ne2000_ioport_read(s, addr);
641     } else if (addr == 0x10) {
642         if (size <= 2) {
643             val = ne2000_asic_ioport_read(s, addr);
644         } else {
645             val = ne2000_asic_ioport_readl(s, addr);
646         }
647     } else if (addr == 0x1f && size == 1) {
648         val = ne2000_reset_ioport_read(s, addr);
649     } else {
650         val = ((uint64_t)1 << (size * 8)) - 1;
651     }
652     trace_ne2000_read(addr, val);
653 
654     return val;
655 }
656 
657 static void ne2000_write(void *opaque, hwaddr addr,
658                          uint64_t data, unsigned size)
659 {
660     NE2000State *s = opaque;
661 
662     trace_ne2000_write(addr, data);
663     if (addr < 0x10 && size == 1) {
664         ne2000_ioport_write(s, addr, data);
665     } else if (addr == 0x10) {
666         if (size <= 2) {
667             ne2000_asic_ioport_write(s, addr, data);
668         } else {
669             ne2000_asic_ioport_writel(s, addr, data);
670         }
671     } else if (addr == 0x1f && size == 1) {
672         ne2000_reset_ioport_write(s, addr, data);
673     }
674 }
675 
676 static const MemoryRegionOps ne2000_ops = {
677     .read = ne2000_read,
678     .write = ne2000_write,
679     .endianness = DEVICE_LITTLE_ENDIAN,
680 };
681 
682 /***********************************************************/
683 /* PCI NE2000 definitions */
684 
685 void ne2000_setup_io(NE2000State *s, DeviceState *dev, unsigned size)
686 {
687     memory_region_init_io(&s->io, OBJECT(dev), &ne2000_ops, s, "ne2000", size);
688 }
689