xref: /openbmc/qemu/hw/net/tulip.c (revision 6016b7b4)
1 /*
2  * QEMU TULIP Emulation
3  *
4  * Copyright (c) 2019 Sven Schnelle <svens@stackframe.org>
5  *
6  * This work is licensed under the GNU GPL license version 2 or later.
7  */
8 
9 #include "qemu/osdep.h"
10 #include "qemu/log.h"
11 #include "hw/irq.h"
12 #include "hw/pci/pci.h"
13 #include "hw/qdev-properties.h"
14 #include "hw/nvram/eeprom93xx.h"
15 #include "migration/vmstate.h"
16 #include "sysemu/sysemu.h"
17 #include "tulip.h"
18 #include "trace.h"
19 #include "net/eth.h"
20 
21 struct TULIPState {
22     PCIDevice dev;
23     MemoryRegion io;
24     MemoryRegion memory;
25     NICConf c;
26     qemu_irq irq;
27     NICState *nic;
28     eeprom_t *eeprom;
29     uint32_t csr[16];
30 
31     /* state for MII */
32     uint32_t old_csr9;
33     uint32_t mii_word;
34     uint32_t mii_bitcnt;
35 
36     hwaddr current_rx_desc;
37     hwaddr current_tx_desc;
38 
39     uint8_t rx_frame[2048];
40     uint8_t tx_frame[2048];
41     uint16_t tx_frame_len;
42     uint16_t rx_frame_len;
43     uint16_t rx_frame_size;
44 
45     uint32_t rx_status;
46     uint8_t filter[16][6];
47 };
48 
49 static const VMStateDescription vmstate_pci_tulip = {
50     .name = "tulip",
51     .fields = (VMStateField[]) {
52         VMSTATE_PCI_DEVICE(dev, TULIPState),
53         VMSTATE_UINT32_ARRAY(csr, TULIPState, 16),
54         VMSTATE_UINT32(old_csr9, TULIPState),
55         VMSTATE_UINT32(mii_word, TULIPState),
56         VMSTATE_UINT32(mii_bitcnt, TULIPState),
57         VMSTATE_UINT64(current_rx_desc, TULIPState),
58         VMSTATE_UINT64(current_tx_desc, TULIPState),
59         VMSTATE_BUFFER(rx_frame, TULIPState),
60         VMSTATE_BUFFER(tx_frame, TULIPState),
61         VMSTATE_UINT16(rx_frame_len, TULIPState),
62         VMSTATE_UINT16(tx_frame_len, TULIPState),
63         VMSTATE_UINT16(rx_frame_size, TULIPState),
64         VMSTATE_UINT32(rx_status, TULIPState),
65         VMSTATE_UINT8_2DARRAY(filter, TULIPState, 16, 6),
66         VMSTATE_END_OF_LIST()
67     }
68 };
69 
70 static void tulip_desc_read(TULIPState *s, hwaddr p,
71         struct tulip_descriptor *desc)
72 {
73     if (s->csr[0] & CSR0_DBO) {
74         desc->status = ldl_be_pci_dma(&s->dev, p);
75         desc->control = ldl_be_pci_dma(&s->dev, p + 4);
76         desc->buf_addr1 = ldl_be_pci_dma(&s->dev, p + 8);
77         desc->buf_addr2 = ldl_be_pci_dma(&s->dev, p + 12);
78     } else {
79         desc->status = ldl_le_pci_dma(&s->dev, p);
80         desc->control = ldl_le_pci_dma(&s->dev, p + 4);
81         desc->buf_addr1 = ldl_le_pci_dma(&s->dev, p + 8);
82         desc->buf_addr2 = ldl_le_pci_dma(&s->dev, p + 12);
83     }
84 }
85 
86 static void tulip_desc_write(TULIPState *s, hwaddr p,
87         struct tulip_descriptor *desc)
88 {
89     if (s->csr[0] & CSR0_DBO) {
90         stl_be_pci_dma(&s->dev, p, desc->status);
91         stl_be_pci_dma(&s->dev, p + 4, desc->control);
92         stl_be_pci_dma(&s->dev, p + 8, desc->buf_addr1);
93         stl_be_pci_dma(&s->dev, p + 12, desc->buf_addr2);
94     } else {
95         stl_le_pci_dma(&s->dev, p, desc->status);
96         stl_le_pci_dma(&s->dev, p + 4, desc->control);
97         stl_le_pci_dma(&s->dev, p + 8, desc->buf_addr1);
98         stl_le_pci_dma(&s->dev, p + 12, desc->buf_addr2);
99     }
100 }
101 
102 static void tulip_update_int(TULIPState *s)
103 {
104     uint32_t ie = s->csr[5] & s->csr[7];
105     bool assert = false;
106 
107     s->csr[5] &= ~(CSR5_AIS | CSR5_NIS);
108 
109     if (ie & (CSR5_TI | CSR5_TU | CSR5_RI | CSR5_GTE | CSR5_ERI)) {
110         s->csr[5] |= CSR5_NIS;
111     }
112 
113     if (ie & (CSR5_LC | CSR5_GPI | CSR5_FBE | CSR5_LNF | CSR5_ETI | CSR5_RWT |
114               CSR5_RPS | CSR5_RU | CSR5_UNF | CSR5_LNP_ANC | CSR5_TJT |
115               CSR5_TPS)) {
116         s->csr[5] |= CSR5_AIS;
117     }
118 
119     assert = s->csr[5] & s->csr[7] & (CSR5_AIS | CSR5_NIS);
120     trace_tulip_irq(s->csr[5], s->csr[7], assert ? "assert" : "deassert");
121     qemu_set_irq(s->irq, assert);
122 }
123 
124 static bool tulip_rx_stopped(TULIPState *s)
125 {
126     return ((s->csr[5] >> CSR5_RS_SHIFT) & CSR5_RS_MASK) == CSR5_RS_STOPPED;
127 }
128 
129 static void tulip_dump_tx_descriptor(TULIPState *s,
130         struct tulip_descriptor *desc)
131 {
132     trace_tulip_descriptor("TX ", s->current_tx_desc,
133                 desc->status, desc->control >> 22,
134                 desc->control & 0x7ff, (desc->control >> 11) & 0x7ff,
135                 desc->buf_addr1, desc->buf_addr2);
136 }
137 
138 static void tulip_dump_rx_descriptor(TULIPState *s,
139         struct tulip_descriptor *desc)
140 {
141     trace_tulip_descriptor("RX ", s->current_rx_desc,
142                 desc->status, desc->control >> 22,
143                 desc->control & 0x7ff, (desc->control >> 11) & 0x7ff,
144                 desc->buf_addr1, desc->buf_addr2);
145 }
146 
147 static void tulip_next_rx_descriptor(TULIPState *s,
148     struct tulip_descriptor *desc)
149 {
150     if (desc->control & RDES1_RER) {
151         s->current_rx_desc = s->csr[3];
152     } else if (desc->control & RDES1_RCH) {
153         s->current_rx_desc = desc->buf_addr2;
154     } else {
155         s->current_rx_desc += sizeof(struct tulip_descriptor) +
156                 (((s->csr[0] >> CSR0_DSL_SHIFT) & CSR0_DSL_MASK) << 2);
157     }
158     s->current_rx_desc &= ~3ULL;
159 }
160 
161 static void tulip_copy_rx_bytes(TULIPState *s, struct tulip_descriptor *desc)
162 {
163     int len1 = (desc->control >> RDES1_BUF1_SIZE_SHIFT) & RDES1_BUF1_SIZE_MASK;
164     int len2 = (desc->control >> RDES1_BUF2_SIZE_SHIFT) & RDES1_BUF2_SIZE_MASK;
165     int len;
166 
167     if (s->rx_frame_len && len1) {
168         if (s->rx_frame_len > len1) {
169             len = len1;
170         } else {
171             len = s->rx_frame_len;
172         }
173 
174         pci_dma_write(&s->dev, desc->buf_addr1, s->rx_frame +
175             (s->rx_frame_size - s->rx_frame_len), len);
176         s->rx_frame_len -= len;
177     }
178 
179     if (s->rx_frame_len && len2) {
180         if (s->rx_frame_len > len2) {
181             len = len2;
182         } else {
183             len = s->rx_frame_len;
184         }
185 
186         pci_dma_write(&s->dev, desc->buf_addr2, s->rx_frame +
187             (s->rx_frame_size - s->rx_frame_len), len);
188         s->rx_frame_len -= len;
189     }
190 }
191 
192 static bool tulip_filter_address(TULIPState *s, const uint8_t *addr)
193 {
194     static const char broadcast[] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
195     bool ret = false;
196     int i;
197 
198     for (i = 0; i < 16 && ret == false; i++) {
199         if (!memcmp(&s->filter[i], addr, ETH_ALEN)) {
200             ret = true;
201         }
202     }
203 
204     if (!memcmp(addr, broadcast, ETH_ALEN)) {
205         return true;
206     }
207 
208     if (s->csr[6] & (CSR6_PR | CSR6_RA)) {
209         /* Promiscuous mode enabled */
210         s->rx_status |= RDES0_FF;
211         return true;
212     }
213 
214     if ((s->csr[6] & CSR6_PM) && (addr[0] & 1)) {
215         /* Pass all Multicast enabled */
216         s->rx_status |= RDES0_MF;
217         return true;
218     }
219 
220     if (s->csr[6] & CSR6_IF) {
221         ret ^= true;
222     }
223     return ret;
224 }
225 
226 static ssize_t tulip_receive(TULIPState *s, const uint8_t *buf, size_t size)
227 {
228     struct tulip_descriptor desc;
229 
230     trace_tulip_receive(buf, size);
231 
232     if (size < 14 || size > sizeof(s->rx_frame) - 4
233         || s->rx_frame_len || tulip_rx_stopped(s)) {
234         return 0;
235     }
236 
237     if (!tulip_filter_address(s, buf)) {
238         return size;
239     }
240 
241     do {
242         tulip_desc_read(s, s->current_rx_desc, &desc);
243         tulip_dump_rx_descriptor(s, &desc);
244 
245         if (!(desc.status & RDES0_OWN)) {
246             s->csr[5] |= CSR5_RU;
247             tulip_update_int(s);
248             return s->rx_frame_size - s->rx_frame_len;
249         }
250         desc.status = 0;
251 
252         if (!s->rx_frame_len) {
253             s->rx_frame_size = size + 4;
254             s->rx_status = RDES0_LS |
255                  ((s->rx_frame_size & RDES0_FL_MASK) << RDES0_FL_SHIFT);
256             desc.status |= RDES0_FS;
257             memcpy(s->rx_frame, buf, size);
258             s->rx_frame_len = s->rx_frame_size;
259         }
260 
261         tulip_copy_rx_bytes(s, &desc);
262 
263         if (!s->rx_frame_len) {
264             desc.status |= s->rx_status;
265             s->csr[5] |= CSR5_RI;
266             tulip_update_int(s);
267         }
268         tulip_dump_rx_descriptor(s, &desc);
269         tulip_desc_write(s, s->current_rx_desc, &desc);
270         tulip_next_rx_descriptor(s, &desc);
271     } while (s->rx_frame_len);
272     return size;
273 }
274 
275 static ssize_t tulip_receive_nc(NetClientState *nc,
276                              const uint8_t *buf, size_t size)
277 {
278     return tulip_receive(qemu_get_nic_opaque(nc), buf, size);
279 }
280 
281 static NetClientInfo net_tulip_info = {
282     .type = NET_CLIENT_DRIVER_NIC,
283     .size = sizeof(NICState),
284     .receive = tulip_receive_nc,
285 };
286 
287 static const char *tulip_reg_name(const hwaddr addr)
288 {
289     switch (addr) {
290     case CSR(0):
291         return "CSR0";
292 
293     case CSR(1):
294         return "CSR1";
295 
296     case CSR(2):
297         return "CSR2";
298 
299     case CSR(3):
300         return "CSR3";
301 
302     case CSR(4):
303         return "CSR4";
304 
305     case CSR(5):
306         return "CSR5";
307 
308     case CSR(6):
309         return "CSR6";
310 
311     case CSR(7):
312         return "CSR7";
313 
314     case CSR(8):
315         return "CSR8";
316 
317     case CSR(9):
318         return "CSR9";
319 
320     case CSR(10):
321         return "CSR10";
322 
323     case CSR(11):
324         return "CSR11";
325 
326     case CSR(12):
327         return "CSR12";
328 
329     case CSR(13):
330         return "CSR13";
331 
332     case CSR(14):
333         return "CSR14";
334 
335     case CSR(15):
336         return "CSR15";
337 
338     default:
339         break;
340     }
341     return "";
342 }
343 
344 static const char *tulip_rx_state_name(int state)
345 {
346     switch (state) {
347     case CSR5_RS_STOPPED:
348         return "STOPPED";
349 
350     case CSR5_RS_RUNNING_FETCH:
351         return "RUNNING/FETCH";
352 
353     case CSR5_RS_RUNNING_CHECK_EOR:
354         return "RUNNING/CHECK EOR";
355 
356     case CSR5_RS_RUNNING_WAIT_RECEIVE:
357         return "WAIT RECEIVE";
358 
359     case CSR5_RS_SUSPENDED:
360         return "SUSPENDED";
361 
362     case CSR5_RS_RUNNING_CLOSE:
363         return "RUNNING/CLOSE";
364 
365     case CSR5_RS_RUNNING_FLUSH:
366         return "RUNNING/FLUSH";
367 
368     case CSR5_RS_RUNNING_QUEUE:
369         return "RUNNING/QUEUE";
370 
371     default:
372         break;
373     }
374     return "";
375 }
376 
377 static const char *tulip_tx_state_name(int state)
378 {
379     switch (state) {
380     case CSR5_TS_STOPPED:
381         return "STOPPED";
382 
383     case CSR5_TS_RUNNING_FETCH:
384         return "RUNNING/FETCH";
385 
386     case CSR5_TS_RUNNING_WAIT_EOT:
387         return "RUNNING/WAIT EOT";
388 
389     case CSR5_TS_RUNNING_READ_BUF:
390         return "RUNNING/READ BUF";
391 
392     case CSR5_TS_RUNNING_SETUP:
393         return "RUNNING/SETUP";
394 
395     case CSR5_TS_SUSPENDED:
396         return "SUSPENDED";
397 
398     case CSR5_TS_RUNNING_CLOSE:
399         return "RUNNING/CLOSE";
400 
401     default:
402         break;
403     }
404     return "";
405 }
406 
407 static void tulip_update_rs(TULIPState *s, int state)
408 {
409     s->csr[5] &= ~(CSR5_RS_MASK << CSR5_RS_SHIFT);
410     s->csr[5] |= (state & CSR5_RS_MASK) << CSR5_RS_SHIFT;
411     trace_tulip_rx_state(tulip_rx_state_name(state));
412 }
413 
414 static uint16_t tulip_mdi_default[] = {
415     /* MDI Registers 0 - 6, 7 */
416     0x3100, 0xf02c, 0x7810, 0x0000, 0x0501, 0x4181, 0x0000, 0x0000,
417     /* MDI Registers 8 - 15 */
418     0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
419     /* MDI Registers 16 - 31 */
420     0x0003, 0x0000, 0x0001, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
421     0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
422 };
423 
424 /* Readonly mask for MDI (PHY) registers */
425 static const uint16_t tulip_mdi_mask[] = {
426     0x0000, 0xffff, 0xffff, 0xffff, 0xc01f, 0xffff, 0xffff, 0x0000,
427     0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
428     0x0fff, 0x0000, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
429     0xffff, 0xffff, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
430 };
431 
432 static uint16_t tulip_mii_read(TULIPState *s, int phy, int reg)
433 {
434     uint16_t ret = 0;
435     if (phy == 1) {
436         ret = tulip_mdi_default[reg];
437     }
438     trace_tulip_mii_read(phy, reg, ret);
439     return ret;
440 }
441 
442 static void tulip_mii_write(TULIPState *s, int phy, int reg, uint16_t data)
443 {
444     trace_tulip_mii_write(phy, reg, data);
445 
446     if (phy != 1) {
447         return;
448     }
449 
450     tulip_mdi_default[reg] &= ~tulip_mdi_mask[reg];
451     tulip_mdi_default[reg] |= (data & tulip_mdi_mask[reg]);
452 }
453 
454 static void tulip_mii(TULIPState *s)
455 {
456     uint32_t changed = s->old_csr9 ^ s->csr[9];
457     uint16_t data;
458     int op, phy, reg;
459 
460     if (!(changed & CSR9_MDC)) {
461         return;
462     }
463 
464     if (!(s->csr[9] & CSR9_MDC)) {
465         return;
466     }
467 
468     s->mii_bitcnt++;
469     s->mii_word <<= 1;
470 
471     if (s->csr[9] & CSR9_MDO && (s->mii_bitcnt < 16 ||
472         !(s->csr[9] & CSR9_MII))) {
473         /* write op or address bits */
474         s->mii_word |= 1;
475     }
476 
477     if (s->mii_bitcnt >= 16 && (s->csr[9] & CSR9_MII)) {
478         if (s->mii_word & 0x8000) {
479             s->csr[9] |= CSR9_MDI;
480         } else {
481             s->csr[9] &= ~CSR9_MDI;
482         }
483     }
484 
485     if (s->mii_word == 0xffffffff) {
486         s->mii_bitcnt = 0;
487     } else if (s->mii_bitcnt == 16) {
488         op = (s->mii_word >> 12) & 0x0f;
489         phy = (s->mii_word >> 7) & 0x1f;
490         reg = (s->mii_word >> 2) & 0x1f;
491 
492         if (op == 6) {
493             s->mii_word = tulip_mii_read(s, phy, reg);
494         }
495     } else if (s->mii_bitcnt == 32) {
496             op = (s->mii_word >> 28) & 0x0f;
497             phy = (s->mii_word >> 23) & 0x1f;
498             reg = (s->mii_word >> 18) & 0x1f;
499             data = s->mii_word & 0xffff;
500 
501         if (op == 5) {
502             tulip_mii_write(s, phy, reg, data);
503         }
504     }
505 }
506 
507 static uint32_t tulip_csr9_read(TULIPState *s)
508 {
509     if (s->csr[9] & CSR9_SR) {
510         if (eeprom93xx_read(s->eeprom)) {
511             s->csr[9] |= CSR9_SR_DO;
512         } else {
513             s->csr[9] &= ~CSR9_SR_DO;
514         }
515     }
516 
517     tulip_mii(s);
518     return s->csr[9];
519 }
520 
521 static void tulip_update_ts(TULIPState *s, int state)
522 {
523         s->csr[5] &= ~(CSR5_TS_MASK << CSR5_TS_SHIFT);
524         s->csr[5] |= (state & CSR5_TS_MASK) << CSR5_TS_SHIFT;
525         trace_tulip_tx_state(tulip_tx_state_name(state));
526 }
527 
528 static uint64_t tulip_read(void *opaque, hwaddr addr,
529                               unsigned size)
530 {
531     TULIPState *s = opaque;
532     uint64_t data = 0;
533 
534     switch (addr) {
535     case CSR(9):
536         data = tulip_csr9_read(s);
537         break;
538 
539     case CSR(12):
540         /* Fake autocompletion complete until we have PHY emulation */
541         data = 5 << CSR12_ANS_SHIFT;
542         break;
543 
544     default:
545         if (addr & 7) {
546             qemu_log_mask(LOG_GUEST_ERROR, "%s: read access at unknown address"
547                 " 0x%"PRIx64"\n", __func__, addr);
548         } else {
549             data = s->csr[addr >> 3];
550         }
551         break;
552     }
553     trace_tulip_reg_read(addr, tulip_reg_name(addr), size, data);
554     return data;
555 }
556 
557 static void tulip_tx(TULIPState *s, struct tulip_descriptor *desc)
558 {
559     if (s->tx_frame_len) {
560         if ((s->csr[6] >> CSR6_OM_SHIFT) & CSR6_OM_MASK) {
561             /* Internal or external Loopback */
562             tulip_receive(s, s->tx_frame, s->tx_frame_len);
563         } else if (s->tx_frame_len <= sizeof(s->tx_frame)) {
564             qemu_send_packet(qemu_get_queue(s->nic),
565                 s->tx_frame, s->tx_frame_len);
566         }
567     }
568 
569     if (desc->control & TDES1_IC) {
570         s->csr[5] |= CSR5_TI;
571         tulip_update_int(s);
572     }
573 }
574 
575 static int tulip_copy_tx_buffers(TULIPState *s, struct tulip_descriptor *desc)
576 {
577     int len1 = (desc->control >> TDES1_BUF1_SIZE_SHIFT) & TDES1_BUF1_SIZE_MASK;
578     int len2 = (desc->control >> TDES1_BUF2_SIZE_SHIFT) & TDES1_BUF2_SIZE_MASK;
579 
580     if (s->tx_frame_len + len1 > sizeof(s->tx_frame)) {
581         qemu_log_mask(LOG_GUEST_ERROR,
582                       "%s: descriptor overflow (ofs: %u, len:%d, size:%zu)\n",
583                       __func__, s->tx_frame_len, len1, sizeof(s->tx_frame));
584         return -1;
585     }
586     if (len1) {
587         pci_dma_read(&s->dev, desc->buf_addr1,
588             s->tx_frame + s->tx_frame_len, len1);
589         s->tx_frame_len += len1;
590     }
591 
592     if (s->tx_frame_len + len2 > sizeof(s->tx_frame)) {
593         qemu_log_mask(LOG_GUEST_ERROR,
594                       "%s: descriptor overflow (ofs: %u, len:%d, size:%zu)\n",
595                       __func__, s->tx_frame_len, len2, sizeof(s->tx_frame));
596         return -1;
597     }
598     if (len2) {
599         pci_dma_read(&s->dev, desc->buf_addr2,
600             s->tx_frame + s->tx_frame_len, len2);
601         s->tx_frame_len += len2;
602     }
603     desc->status = (len1 + len2) ? 0 : 0x7fffffff;
604 
605     return 0;
606 }
607 
608 static void tulip_setup_filter_addr(TULIPState *s, uint8_t *buf, int n)
609 {
610     int offset = n * 12;
611 
612     s->filter[n][0] = buf[offset];
613     s->filter[n][1] = buf[offset + 1];
614 
615     s->filter[n][2] = buf[offset + 4];
616     s->filter[n][3] = buf[offset + 5];
617 
618     s->filter[n][4] = buf[offset + 8];
619     s->filter[n][5] = buf[offset + 9];
620 
621     trace_tulip_setup_filter(n, s->filter[n][5], s->filter[n][4],
622             s->filter[n][3], s->filter[n][2], s->filter[n][1], s->filter[n][0]);
623 }
624 
625 static void tulip_setup_frame(TULIPState *s,
626         struct tulip_descriptor *desc)
627 {
628     uint8_t buf[4096];
629     int len = (desc->control >> TDES1_BUF1_SIZE_SHIFT) & TDES1_BUF1_SIZE_MASK;
630     int i;
631 
632     trace_tulip_setup_frame();
633 
634     if (len == 192) {
635         pci_dma_read(&s->dev, desc->buf_addr1, buf, len);
636         for (i = 0; i < 16; i++) {
637             tulip_setup_filter_addr(s, buf, i);
638         }
639     }
640 
641     desc->status = 0x7fffffff;
642 
643     if (desc->control & TDES1_IC) {
644         s->csr[5] |= CSR5_TI;
645         tulip_update_int(s);
646     }
647 }
648 
649 static void tulip_next_tx_descriptor(TULIPState *s,
650     struct tulip_descriptor *desc)
651 {
652     if (desc->control & TDES1_TER) {
653         s->current_tx_desc = s->csr[4];
654     } else if (desc->control & TDES1_TCH) {
655         s->current_tx_desc = desc->buf_addr2;
656     } else {
657         s->current_tx_desc += sizeof(struct tulip_descriptor) +
658                 (((s->csr[0] >> CSR0_DSL_SHIFT) & CSR0_DSL_MASK) << 2);
659     }
660     s->current_tx_desc &= ~3ULL;
661 }
662 
663 static uint32_t tulip_ts(TULIPState *s)
664 {
665     return (s->csr[5] >> CSR5_TS_SHIFT) & CSR5_TS_MASK;
666 }
667 
668 static void tulip_xmit_list_update(TULIPState *s)
669 {
670 #define TULIP_DESC_MAX 128
671     uint8_t i = 0;
672     struct tulip_descriptor desc;
673 
674     if (tulip_ts(s) != CSR5_TS_SUSPENDED) {
675         return;
676     }
677 
678     for (i = 0; i < TULIP_DESC_MAX; i++) {
679         tulip_desc_read(s, s->current_tx_desc, &desc);
680         tulip_dump_tx_descriptor(s, &desc);
681 
682         if (!(desc.status & TDES0_OWN)) {
683             tulip_update_ts(s, CSR5_TS_SUSPENDED);
684             s->csr[5] |= CSR5_TU;
685             tulip_update_int(s);
686             return;
687         }
688 
689         if (desc.control & TDES1_SET) {
690             tulip_setup_frame(s, &desc);
691         } else {
692             if (desc.control & TDES1_FS) {
693                 s->tx_frame_len = 0;
694             }
695 
696             if (!tulip_copy_tx_buffers(s, &desc)) {
697                 if (desc.control & TDES1_LS) {
698                     tulip_tx(s, &desc);
699                 }
700             }
701         }
702         tulip_desc_write(s, s->current_tx_desc, &desc);
703         tulip_next_tx_descriptor(s, &desc);
704     }
705 }
706 
707 static void tulip_csr9_write(TULIPState *s, uint32_t old_val,
708         uint32_t new_val)
709 {
710     if (new_val & CSR9_SR) {
711         eeprom93xx_write(s->eeprom,
712             !!(new_val & CSR9_SR_CS),
713             !!(new_val & CSR9_SR_SK),
714             !!(new_val & CSR9_SR_DI));
715     }
716 }
717 
718 static void tulip_reset(TULIPState *s)
719 {
720     trace_tulip_reset();
721 
722     s->csr[0] = 0xfe000000;
723     s->csr[1] = 0xffffffff;
724     s->csr[2] = 0xffffffff;
725     s->csr[5] = 0xf0000000;
726     s->csr[6] = 0x32000040;
727     s->csr[7] = 0xf3fe0000;
728     s->csr[8] = 0xe0000000;
729     s->csr[9] = 0xfff483ff;
730     s->csr[11] = 0xfffe0000;
731     s->csr[12] = 0x000000c6;
732     s->csr[13] = 0xffff0000;
733     s->csr[14] = 0xffffffff;
734     s->csr[15] = 0x8ff00000;
735 }
736 
737 static void tulip_qdev_reset(DeviceState *dev)
738 {
739     PCIDevice *d = PCI_DEVICE(dev);
740     TULIPState *s = TULIP(d);
741 
742     tulip_reset(s);
743 }
744 
745 static void tulip_write(void *opaque, hwaddr addr,
746                            uint64_t data, unsigned size)
747 {
748     TULIPState *s = opaque;
749     trace_tulip_reg_write(addr, tulip_reg_name(addr), size, data);
750 
751     switch (addr) {
752     case CSR(0):
753         s->csr[0] = data;
754         if (data & CSR0_SWR) {
755             tulip_reset(s);
756             tulip_update_int(s);
757         }
758         break;
759 
760     case CSR(1):
761         tulip_xmit_list_update(s);
762         break;
763 
764     case CSR(2):
765         qemu_flush_queued_packets(qemu_get_queue(s->nic));
766         break;
767 
768     case CSR(3):
769         s->csr[3] = data & ~3ULL;
770         s->current_rx_desc = s->csr[3];
771         qemu_flush_queued_packets(qemu_get_queue(s->nic));
772         break;
773 
774     case CSR(4):
775         s->csr[4] = data & ~3ULL;
776         s->current_tx_desc = s->csr[4];
777         tulip_xmit_list_update(s);
778         break;
779 
780     case CSR(5):
781         /* Status register, write clears bit */
782         s->csr[5] &= ~(data & (CSR5_TI | CSR5_TPS | CSR5_TU | CSR5_TJT |
783                                CSR5_LNP_ANC | CSR5_UNF | CSR5_RI | CSR5_RU |
784                                CSR5_RPS | CSR5_RWT | CSR5_ETI | CSR5_GTE |
785                                CSR5_LNF | CSR5_FBE | CSR5_ERI | CSR5_AIS |
786                                CSR5_NIS | CSR5_GPI | CSR5_LC));
787         tulip_update_int(s);
788         break;
789 
790     case CSR(6):
791         s->csr[6] = data;
792         if (s->csr[6] & CSR6_SR) {
793             tulip_update_rs(s, CSR5_RS_RUNNING_WAIT_RECEIVE);
794             qemu_flush_queued_packets(qemu_get_queue(s->nic));
795         } else {
796             tulip_update_rs(s, CSR5_RS_STOPPED);
797         }
798 
799         if (s->csr[6] & CSR6_ST) {
800             tulip_update_ts(s, CSR5_TS_SUSPENDED);
801             tulip_xmit_list_update(s);
802         } else {
803             tulip_update_ts(s, CSR5_TS_STOPPED);
804         }
805         break;
806 
807     case CSR(7):
808         s->csr[7] = data;
809         tulip_update_int(s);
810         break;
811 
812     case CSR(8):
813         s->csr[9] = data;
814         break;
815 
816     case CSR(9):
817         tulip_csr9_write(s, s->csr[9], data);
818         /* don't clear MII read data */
819         s->csr[9] &= CSR9_MDI;
820         s->csr[9] |= (data & ~CSR9_MDI);
821         tulip_mii(s);
822         s->old_csr9 = s->csr[9];
823         break;
824 
825     case CSR(10):
826         s->csr[10] = data;
827         break;
828 
829     case CSR(11):
830         s->csr[11] = data;
831         break;
832 
833     case CSR(12):
834         /* SIA Status register, some bits are cleared by writing 1 */
835         s->csr[12] &= ~(data & (CSR12_MRA | CSR12_TRA | CSR12_ARA));
836         break;
837 
838     case CSR(13):
839         s->csr[13] = data;
840         break;
841 
842     case CSR(14):
843         s->csr[14] = data;
844         break;
845 
846     case CSR(15):
847         s->csr[15] = data;
848         break;
849 
850     default:
851         qemu_log_mask(LOG_GUEST_ERROR, "%s: write to CSR at unknown address "
852                 "0x%"PRIx64"\n", __func__, addr);
853         break;
854     }
855 }
856 
857 static const MemoryRegionOps tulip_ops = {
858     .read = tulip_read,
859     .write = tulip_write,
860     .endianness = DEVICE_LITTLE_ENDIAN,
861     .impl = {
862         .min_access_size = 4,
863         .max_access_size = 4,
864     },
865 };
866 
867 static void tulip_idblock_crc(TULIPState *s, uint16_t *srom)
868 {
869     int word, n;
870     int bit;
871     unsigned char bitval, crc;
872     const int len = 9;
873     n = 0;
874     crc = -1;
875 
876     for (word = 0; word < len; word++) {
877         for (bit = 15; bit >= 0; bit--) {
878             if ((word == (len - 1)) && (bit == 7)) {
879                 /*
880                  * Insert the correct CRC result into input data stream
881                  * in place.
882                  */
883                 srom[len - 1] = (srom[len - 1] & 0xff00) | (unsigned short)crc;
884                 break;
885             }
886             n++;
887             bitval = ((srom[word] >> bit) & 1) ^ ((crc >> 7) & 1);
888             crc = crc << 1;
889             if (bitval == 1) {
890                 crc ^= 6;
891                 crc |= 0x01;
892             }
893         }
894     }
895 }
896 
897 static uint16_t tulip_srom_crc(TULIPState *s, uint8_t *eeprom, size_t len)
898 {
899     unsigned long crc = 0xffffffff;
900     unsigned long flippedcrc = 0;
901     unsigned char currentbyte;
902     unsigned int msb, bit, i;
903 
904     for (i = 0; i < len; i++) {
905         currentbyte = eeprom[i];
906         for (bit = 0; bit < 8; bit++) {
907             msb = (crc >> 31) & 1;
908             crc <<= 1;
909             if (msb ^ (currentbyte & 1)) {
910                 crc ^= 0x04c11db6;
911                 crc |= 0x00000001;
912             }
913             currentbyte >>= 1;
914         }
915     }
916 
917     for (i = 0; i < 32; i++) {
918         flippedcrc <<= 1;
919         bit = crc & 1;
920         crc >>= 1;
921         flippedcrc += bit;
922     }
923     return (flippedcrc ^ 0xffffffff) & 0xffff;
924 }
925 
926 static const uint8_t eeprom_default[128] = {
927     0x3c, 0x10, 0x4f, 0x10, 0x00, 0x00, 0x00, 0x00,
928     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
929     0x56, 0x08, 0x04, 0x01, 0x00, 0x80, 0x48, 0xb3,
930     0x0e, 0xa7, 0x00, 0x1e, 0x00, 0x00, 0x00, 0x08,
931     0x01, 0x8d, 0x03, 0x00, 0x00, 0x00, 0x00, 0x78,
932     0xe0, 0x01, 0x00, 0x50, 0x00, 0x18, 0x00, 0x00,
933     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
934     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
935     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
936     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
937     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
938     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xe8, 0x6b,
939     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80,
940     0x48, 0xb3, 0x0e, 0xa7, 0x40, 0x00, 0x00, 0x00,
941     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
942     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
943 };
944 
945 static void tulip_fill_eeprom(TULIPState *s)
946 {
947     uint16_t *eeprom = eeprom93xx_data(s->eeprom);
948     memcpy(eeprom, eeprom_default, 128);
949 
950     /* patch in our mac address */
951     eeprom[10] = cpu_to_le16(s->c.macaddr.a[0] | (s->c.macaddr.a[1] << 8));
952     eeprom[11] = cpu_to_le16(s->c.macaddr.a[2] | (s->c.macaddr.a[3] << 8));
953     eeprom[12] = cpu_to_le16(s->c.macaddr.a[4] | (s->c.macaddr.a[5] << 8));
954     tulip_idblock_crc(s, eeprom);
955     eeprom[63] = cpu_to_le16(tulip_srom_crc(s, (uint8_t *)eeprom, 126));
956 }
957 
958 static void pci_tulip_realize(PCIDevice *pci_dev, Error **errp)
959 {
960     TULIPState *s = DO_UPCAST(TULIPState, dev, pci_dev);
961     uint8_t *pci_conf;
962 
963     pci_conf = s->dev.config;
964     pci_conf[PCI_INTERRUPT_PIN] = 1; /* interrupt pin A */
965 
966     s->eeprom = eeprom93xx_new(&pci_dev->qdev, 64);
967     tulip_fill_eeprom(s);
968 
969     memory_region_init_io(&s->io, OBJECT(&s->dev), &tulip_ops, s,
970             "tulip-io", 128);
971 
972     memory_region_init_io(&s->memory, OBJECT(&s->dev), &tulip_ops, s,
973             "tulip-mem", 128);
974 
975     pci_register_bar(&s->dev, 0, PCI_BASE_ADDRESS_SPACE_IO, &s->io);
976     pci_register_bar(&s->dev, 1, PCI_BASE_ADDRESS_SPACE_MEMORY, &s->memory);
977 
978     s->irq = pci_allocate_irq(&s->dev);
979 
980     qemu_macaddr_default_if_unset(&s->c.macaddr);
981 
982     s->nic = qemu_new_nic(&net_tulip_info, &s->c,
983                           object_get_typename(OBJECT(pci_dev)),
984                           pci_dev->qdev.id, s);
985     qemu_format_nic_info_str(qemu_get_queue(s->nic), s->c.macaddr.a);
986 }
987 
988 static void pci_tulip_exit(PCIDevice *pci_dev)
989 {
990     TULIPState *s = DO_UPCAST(TULIPState, dev, pci_dev);
991 
992     qemu_del_nic(s->nic);
993     qemu_free_irq(s->irq);
994     eeprom93xx_free(&pci_dev->qdev, s->eeprom);
995 }
996 
997 static void tulip_instance_init(Object *obj)
998 {
999     PCIDevice *pci_dev = PCI_DEVICE(obj);
1000     TULIPState *d = DO_UPCAST(TULIPState, dev, pci_dev);
1001 
1002     device_add_bootindex_property(obj, &d->c.bootindex,
1003                                   "bootindex", "/ethernet-phy@0",
1004                                   &pci_dev->qdev);
1005 }
1006 
1007 static Property tulip_properties[] = {
1008     DEFINE_NIC_PROPERTIES(TULIPState, c),
1009     DEFINE_PROP_END_OF_LIST(),
1010 };
1011 
1012 static void tulip_class_init(ObjectClass *klass, void *data)
1013 {
1014     DeviceClass *dc = DEVICE_CLASS(klass);
1015     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
1016 
1017     k->realize = pci_tulip_realize;
1018     k->exit = pci_tulip_exit;
1019     k->vendor_id = PCI_VENDOR_ID_DEC;
1020     k->device_id = PCI_DEVICE_ID_DEC_21143;
1021     k->subsystem_vendor_id = 0x103c;
1022     k->subsystem_id = 0x104f;
1023     k->class_id = PCI_CLASS_NETWORK_ETHERNET;
1024     dc->vmsd = &vmstate_pci_tulip;
1025     device_class_set_props(dc, tulip_properties);
1026     dc->reset = tulip_qdev_reset;
1027     set_bit(DEVICE_CATEGORY_NETWORK, dc->categories);
1028 }
1029 
1030 static const TypeInfo tulip_info = {
1031     .name          = TYPE_TULIP,
1032     .parent        = TYPE_PCI_DEVICE,
1033     .instance_size = sizeof(TULIPState),
1034     .class_init    = tulip_class_init,
1035     .instance_init = tulip_instance_init,
1036     .interfaces = (InterfaceInfo[]) {
1037         { INTERFACE_CONVENTIONAL_PCI_DEVICE },
1038         { },
1039     },
1040 };
1041 
1042 static void tulip_register_types(void)
1043 {
1044     type_register_static(&tulip_info);
1045 }
1046 
1047 type_init(tulip_register_types)
1048