xref: /qemu/hw/net/dp8393x.c (revision 67b38ddfe58cbfb7c9c4a8d8b7efdc3fe7def41f)
1 /*
2  * QEMU NS SONIC DP8393x netcard
3  *
4  * Copyright (c) 2008-2009 Herve Poussineau
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License as
8  * published by the Free Software Foundation; either version 2 of
9  * the License, or (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License along
17  * with this program; if not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include "qemu/osdep.h"
21 #include "hw/irq.h"
22 #include "hw/qdev-properties.h"
23 #include "hw/sysbus.h"
24 #include "migration/vmstate.h"
25 #include "net/net.h"
26 #include "qapi/error.h"
27 #include "qemu/module.h"
28 #include "qemu/timer.h"
29 #include <zlib.h>
30 #include "qom/object.h"
31 #include "trace.h"
32 
33 static const char *reg_names[] = {
34     "CR", "DCR", "RCR", "TCR", "IMR", "ISR", "UTDA", "CTDA",
35     "TPS", "TFC", "TSA0", "TSA1", "TFS", "URDA", "CRDA", "CRBA0",
36     "CRBA1", "RBWC0", "RBWC1", "EOBC", "URRA", "RSA", "REA", "RRP",
37     "RWP", "TRBA0", "TRBA1", "0x1b", "0x1c", "0x1d", "0x1e", "LLFA",
38     "TTDA", "CEP", "CAP2", "CAP1", "CAP0", "CE", "CDP", "CDC",
39     "SR", "WT0", "WT1", "RSC", "CRCT", "FAET", "MPT", "MDT",
40     "0x30", "0x31", "0x32", "0x33", "0x34", "0x35", "0x36", "0x37",
41     "0x38", "0x39", "0x3a", "0x3b", "0x3c", "0x3d", "0x3e", "DCR2" };
42 
43 #define SONIC_CR     0x00
44 #define SONIC_DCR    0x01
45 #define SONIC_RCR    0x02
46 #define SONIC_TCR    0x03
47 #define SONIC_IMR    0x04
48 #define SONIC_ISR    0x05
49 #define SONIC_UTDA   0x06
50 #define SONIC_CTDA   0x07
51 #define SONIC_TPS    0x08
52 #define SONIC_TFC    0x09
53 #define SONIC_TSA0   0x0a
54 #define SONIC_TSA1   0x0b
55 #define SONIC_TFS    0x0c
56 #define SONIC_URDA   0x0d
57 #define SONIC_CRDA   0x0e
58 #define SONIC_CRBA0  0x0f
59 #define SONIC_CRBA1  0x10
60 #define SONIC_RBWC0  0x11
61 #define SONIC_RBWC1  0x12
62 #define SONIC_EOBC   0x13
63 #define SONIC_URRA   0x14
64 #define SONIC_RSA    0x15
65 #define SONIC_REA    0x16
66 #define SONIC_RRP    0x17
67 #define SONIC_RWP    0x18
68 #define SONIC_TRBA0  0x19
69 #define SONIC_TRBA1  0x1a
70 #define SONIC_LLFA   0x1f
71 #define SONIC_TTDA   0x20
72 #define SONIC_CEP    0x21
73 #define SONIC_CAP2   0x22
74 #define SONIC_CAP1   0x23
75 #define SONIC_CAP0   0x24
76 #define SONIC_CE     0x25
77 #define SONIC_CDP    0x26
78 #define SONIC_CDC    0x27
79 #define SONIC_SR     0x28
80 #define SONIC_WT0    0x29
81 #define SONIC_WT1    0x2a
82 #define SONIC_RSC    0x2b
83 #define SONIC_CRCT   0x2c
84 #define SONIC_FAET   0x2d
85 #define SONIC_MPT    0x2e
86 #define SONIC_MDT    0x2f
87 #define SONIC_DCR2   0x3f
88 #define SONIC_REG_COUNT  0x40
89 
90 #define SONIC_CR_HTX     0x0001
91 #define SONIC_CR_TXP     0x0002
92 #define SONIC_CR_RXDIS   0x0004
93 #define SONIC_CR_RXEN    0x0008
94 #define SONIC_CR_STP     0x0010
95 #define SONIC_CR_ST      0x0020
96 #define SONIC_CR_RST     0x0080
97 #define SONIC_CR_RRRA    0x0100
98 #define SONIC_CR_LCAM    0x0200
99 #define SONIC_CR_MASK    0x03bf
100 
101 #define SONIC_DCR_DW     0x0020
102 #define SONIC_DCR_LBR    0x2000
103 #define SONIC_DCR_EXBUS  0x8000
104 
105 #define SONIC_RCR_PRX    0x0001
106 #define SONIC_RCR_LBK    0x0002
107 #define SONIC_RCR_FAER   0x0004
108 #define SONIC_RCR_CRCR   0x0008
109 #define SONIC_RCR_CRS    0x0020
110 #define SONIC_RCR_LPKT   0x0040
111 #define SONIC_RCR_BC     0x0080
112 #define SONIC_RCR_MC     0x0100
113 #define SONIC_RCR_LB0    0x0200
114 #define SONIC_RCR_LB1    0x0400
115 #define SONIC_RCR_AMC    0x0800
116 #define SONIC_RCR_PRO    0x1000
117 #define SONIC_RCR_BRD    0x2000
118 #define SONIC_RCR_RNT    0x4000
119 
120 #define SONIC_TCR_PTX    0x0001
121 #define SONIC_TCR_BCM    0x0002
122 #define SONIC_TCR_FU     0x0004
123 #define SONIC_TCR_EXC    0x0040
124 #define SONIC_TCR_CRSL   0x0080
125 #define SONIC_TCR_NCRS   0x0100
126 #define SONIC_TCR_EXD    0x0400
127 #define SONIC_TCR_CRCI   0x2000
128 #define SONIC_TCR_PINT   0x8000
129 
130 #define SONIC_ISR_RBAE   0x0010
131 #define SONIC_ISR_RBE    0x0020
132 #define SONIC_ISR_RDE    0x0040
133 #define SONIC_ISR_TC     0x0080
134 #define SONIC_ISR_TXDN   0x0200
135 #define SONIC_ISR_PKTRX  0x0400
136 #define SONIC_ISR_PINT   0x0800
137 #define SONIC_ISR_LCD    0x1000
138 
139 #define SONIC_DESC_EOL   0x0001
140 #define SONIC_DESC_ADDR  0xFFFE
141 
142 #define TYPE_DP8393X "dp8393x"
143 OBJECT_DECLARE_SIMPLE_TYPE(dp8393xState, DP8393X)
144 
145 struct dp8393xState {
146     SysBusDevice parent_obj;
147 
148     /* Hardware */
149     uint8_t it_shift;
150     bool big_endian;
151     bool last_rba_is_full;
152     qemu_irq irq;
153     int irq_level;
154     QEMUTimer *watchdog;
155     int64_t wt_last_update;
156     NICConf conf;
157     NICState *nic;
158     MemoryRegion mmio;
159 
160     /* Registers */
161     uint8_t cam[16][6];
162     uint16_t regs[SONIC_REG_COUNT];
163 
164     /* Temporaries */
165     uint8_t tx_buffer[0x10000];
166     uint16_t data[12];
167     int loopback_packet;
168 
169     /* Memory access */
170     MemoryRegion *dma_mr;
171     AddressSpace as;
172 };
173 
174 /*
175  * Accessor functions for values which are formed by
176  * concatenating two 16 bit device registers. By putting these
177  * in their own functions with a uint32_t return type we avoid the
178  * pitfall of implicit sign extension where ((x << 16) | y) is a
179  * signed 32 bit integer that might get sign-extended to a 64 bit integer.
180  */
181 static uint32_t dp8393x_cdp(dp8393xState *s)
182 {
183     return (s->regs[SONIC_URRA] << 16) | s->regs[SONIC_CDP];
184 }
185 
186 static uint32_t dp8393x_crba(dp8393xState *s)
187 {
188     return (s->regs[SONIC_CRBA1] << 16) | s->regs[SONIC_CRBA0];
189 }
190 
191 static uint32_t dp8393x_crda(dp8393xState *s)
192 {
193     return (s->regs[SONIC_URDA] << 16) |
194            (s->regs[SONIC_CRDA] & SONIC_DESC_ADDR);
195 }
196 
197 static uint32_t dp8393x_rbwc(dp8393xState *s)
198 {
199     return (s->regs[SONIC_RBWC1] << 16) | s->regs[SONIC_RBWC0];
200 }
201 
202 static uint32_t dp8393x_rrp(dp8393xState *s)
203 {
204     return (s->regs[SONIC_URRA] << 16) | s->regs[SONIC_RRP];
205 }
206 
207 static uint32_t dp8393x_tsa(dp8393xState *s)
208 {
209     return (s->regs[SONIC_TSA1] << 16) | s->regs[SONIC_TSA0];
210 }
211 
212 static uint32_t dp8393x_ttda(dp8393xState *s)
213 {
214     return (s->regs[SONIC_UTDA] << 16) |
215            (s->regs[SONIC_TTDA] & SONIC_DESC_ADDR);
216 }
217 
218 static uint32_t dp8393x_wt(dp8393xState *s)
219 {
220     return s->regs[SONIC_WT1] << 16 | s->regs[SONIC_WT0];
221 }
222 
223 static uint16_t dp8393x_get(dp8393xState *s, int width, int offset)
224 {
225     uint16_t val;
226 
227     if (s->big_endian) {
228         val = be16_to_cpu(s->data[offset * width + width - 1]);
229     } else {
230         val = le16_to_cpu(s->data[offset * width]);
231     }
232     return val;
233 }
234 
235 static void dp8393x_put(dp8393xState *s, int width, int offset,
236                         uint16_t val)
237 {
238     if (s->big_endian) {
239         if (width == 2) {
240             s->data[offset * 2] = 0;
241             s->data[offset * 2 + 1] = cpu_to_be16(val);
242         } else {
243             s->data[offset] = cpu_to_be16(val);
244         }
245     } else {
246         if (width == 2) {
247             s->data[offset * 2] = cpu_to_le16(val);
248             s->data[offset * 2 + 1] = 0;
249         } else {
250             s->data[offset] = cpu_to_le16(val);
251         }
252     }
253 }
254 
255 static void dp8393x_update_irq(dp8393xState *s)
256 {
257     int level = (s->regs[SONIC_IMR] & s->regs[SONIC_ISR]) ? 1 : 0;
258 
259     if (level != s->irq_level) {
260         s->irq_level = level;
261         if (level) {
262             trace_dp8393x_raise_irq(s->regs[SONIC_ISR]);
263         } else {
264             trace_dp8393x_lower_irq();
265         }
266     }
267 
268     qemu_set_irq(s->irq, level);
269 }
270 
271 static void dp8393x_do_load_cam(dp8393xState *s)
272 {
273     int width, size;
274     uint16_t index;
275 
276     width = (s->regs[SONIC_DCR] & SONIC_DCR_DW) ? 2 : 1;
277     size = sizeof(uint16_t) * 4 * width;
278 
279     while (s->regs[SONIC_CDC] & 0x1f) {
280         /* Fill current entry */
281         address_space_read(&s->as, dp8393x_cdp(s),
282                            MEMTXATTRS_UNSPECIFIED, s->data, size);
283         index = dp8393x_get(s, width, 0) & 0xf;
284         s->cam[index][0] = dp8393x_get(s, width, 1) & 0xff;
285         s->cam[index][1] = dp8393x_get(s, width, 1) >> 8;
286         s->cam[index][2] = dp8393x_get(s, width, 2) & 0xff;
287         s->cam[index][3] = dp8393x_get(s, width, 2) >> 8;
288         s->cam[index][4] = dp8393x_get(s, width, 3) & 0xff;
289         s->cam[index][5] = dp8393x_get(s, width, 3) >> 8;
290         trace_dp8393x_load_cam(index, s->cam[index][0], s->cam[index][1],
291                                s->cam[index][2], s->cam[index][3],
292                                s->cam[index][4], s->cam[index][5]);
293         /* Move to next entry */
294         s->regs[SONIC_CDC]--;
295         s->regs[SONIC_CDP] += size;
296     }
297 
298     /* Read CAM enable */
299     address_space_read(&s->as, dp8393x_cdp(s),
300                        MEMTXATTRS_UNSPECIFIED, s->data, size);
301     s->regs[SONIC_CE] = dp8393x_get(s, width, 0);
302     trace_dp8393x_load_cam_done(s->regs[SONIC_CE]);
303 
304     /* Done */
305     s->regs[SONIC_CR] &= ~SONIC_CR_LCAM;
306     s->regs[SONIC_ISR] |= SONIC_ISR_LCD;
307     dp8393x_update_irq(s);
308 }
309 
310 static void dp8393x_do_read_rra(dp8393xState *s)
311 {
312     int width, size;
313 
314     /* Read memory */
315     width = (s->regs[SONIC_DCR] & SONIC_DCR_DW) ? 2 : 1;
316     size = sizeof(uint16_t) * 4 * width;
317     address_space_read(&s->as, dp8393x_rrp(s),
318                        MEMTXATTRS_UNSPECIFIED, s->data, size);
319 
320     /* Update SONIC registers */
321     s->regs[SONIC_CRBA0] = dp8393x_get(s, width, 0);
322     s->regs[SONIC_CRBA1] = dp8393x_get(s, width, 1);
323     s->regs[SONIC_RBWC0] = dp8393x_get(s, width, 2);
324     s->regs[SONIC_RBWC1] = dp8393x_get(s, width, 3);
325     trace_dp8393x_read_rra_regs(s->regs[SONIC_CRBA0], s->regs[SONIC_CRBA1],
326                                 s->regs[SONIC_RBWC0], s->regs[SONIC_RBWC1]);
327 
328     /* Go to next entry */
329     s->regs[SONIC_RRP] += size;
330 
331     /* Handle wrap */
332     if (s->regs[SONIC_RRP] == s->regs[SONIC_REA]) {
333         s->regs[SONIC_RRP] = s->regs[SONIC_RSA];
334     }
335 
336     /* Warn the host if CRBA now has the last available resource */
337     if (s->regs[SONIC_RRP] == s->regs[SONIC_RWP]) {
338         s->regs[SONIC_ISR] |= SONIC_ISR_RBE;
339         dp8393x_update_irq(s);
340     }
341 
342     /* Allow packet reception */
343     s->last_rba_is_full = false;
344 }
345 
346 static void dp8393x_do_software_reset(dp8393xState *s)
347 {
348     timer_del(s->watchdog);
349 
350     s->regs[SONIC_CR] &= ~(SONIC_CR_LCAM | SONIC_CR_RRRA | SONIC_CR_TXP |
351                            SONIC_CR_HTX);
352     s->regs[SONIC_CR] |= SONIC_CR_RST | SONIC_CR_RXDIS;
353 }
354 
355 static void dp8393x_set_next_tick(dp8393xState *s)
356 {
357     uint32_t ticks;
358     int64_t delay;
359 
360     if (s->regs[SONIC_CR] & SONIC_CR_STP) {
361         timer_del(s->watchdog);
362         return;
363     }
364 
365     ticks = dp8393x_wt(s);
366     s->wt_last_update = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
367     delay = NANOSECONDS_PER_SECOND * ticks / 5000000;
368     timer_mod(s->watchdog, s->wt_last_update + delay);
369 }
370 
371 static void dp8393x_update_wt_regs(dp8393xState *s)
372 {
373     int64_t elapsed;
374     uint32_t val;
375 
376     if (s->regs[SONIC_CR] & SONIC_CR_STP) {
377         timer_del(s->watchdog);
378         return;
379     }
380 
381     elapsed = s->wt_last_update - qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
382     val = dp8393x_wt(s);
383     val -= elapsed / 5000000;
384     s->regs[SONIC_WT1] = (val >> 16) & 0xffff;
385     s->regs[SONIC_WT0] = (val >> 0)  & 0xffff;
386     dp8393x_set_next_tick(s);
387 
388 }
389 
390 static void dp8393x_do_start_timer(dp8393xState *s)
391 {
392     s->regs[SONIC_CR] &= ~SONIC_CR_STP;
393     dp8393x_set_next_tick(s);
394 }
395 
396 static void dp8393x_do_stop_timer(dp8393xState *s)
397 {
398     s->regs[SONIC_CR] &= ~SONIC_CR_ST;
399     dp8393x_update_wt_regs(s);
400 }
401 
402 static bool dp8393x_can_receive(NetClientState *nc);
403 
404 static void dp8393x_do_receiver_enable(dp8393xState *s)
405 {
406     s->regs[SONIC_CR] &= ~SONIC_CR_RXDIS;
407     if (dp8393x_can_receive(s->nic->ncs)) {
408         qemu_flush_queued_packets(qemu_get_queue(s->nic));
409     }
410 }
411 
412 static void dp8393x_do_receiver_disable(dp8393xState *s)
413 {
414     s->regs[SONIC_CR] &= ~SONIC_CR_RXEN;
415 }
416 
417 static void dp8393x_do_transmit_packets(dp8393xState *s)
418 {
419     NetClientState *nc = qemu_get_queue(s->nic);
420     int width, size;
421     int tx_len, len;
422     uint16_t i;
423 
424     width = (s->regs[SONIC_DCR] & SONIC_DCR_DW) ? 2 : 1;
425 
426     while (1) {
427         /* Read memory */
428         size = sizeof(uint16_t) * 6 * width;
429         s->regs[SONIC_TTDA] = s->regs[SONIC_CTDA];
430         trace_dp8393x_transmit_packet(dp8393x_ttda(s));
431         address_space_read(&s->as, dp8393x_ttda(s) + sizeof(uint16_t) * width,
432                            MEMTXATTRS_UNSPECIFIED, s->data, size);
433         tx_len = 0;
434 
435         /* Update registers */
436         s->regs[SONIC_TCR] = dp8393x_get(s, width, 0) & 0xf000;
437         s->regs[SONIC_TPS] = dp8393x_get(s, width, 1);
438         s->regs[SONIC_TFC] = dp8393x_get(s, width, 2);
439         s->regs[SONIC_TSA0] = dp8393x_get(s, width, 3);
440         s->regs[SONIC_TSA1] = dp8393x_get(s, width, 4);
441         s->regs[SONIC_TFS] = dp8393x_get(s, width, 5);
442 
443         /* Handle programmable interrupt */
444         if (s->regs[SONIC_TCR] & SONIC_TCR_PINT) {
445             s->regs[SONIC_ISR] |= SONIC_ISR_PINT;
446         } else {
447             s->regs[SONIC_ISR] &= ~SONIC_ISR_PINT;
448         }
449 
450         for (i = 0; i < s->regs[SONIC_TFC]; ) {
451             /* Append fragment */
452             len = s->regs[SONIC_TFS];
453             if (tx_len + len > sizeof(s->tx_buffer)) {
454                 len = sizeof(s->tx_buffer) - tx_len;
455             }
456             address_space_read(&s->as, dp8393x_tsa(s), MEMTXATTRS_UNSPECIFIED,
457                                &s->tx_buffer[tx_len], len);
458             tx_len += len;
459 
460             i++;
461             if (i != s->regs[SONIC_TFC]) {
462                 /* Read next fragment details */
463                 size = sizeof(uint16_t) * 3 * width;
464                 address_space_read(&s->as,
465                                    dp8393x_ttda(s)
466                                    + sizeof(uint16_t) * width * (4 + 3 * i),
467                                    MEMTXATTRS_UNSPECIFIED, s->data,
468                                    size);
469                 s->regs[SONIC_TSA0] = dp8393x_get(s, width, 0);
470                 s->regs[SONIC_TSA1] = dp8393x_get(s, width, 1);
471                 s->regs[SONIC_TFS] = dp8393x_get(s, width, 2);
472             }
473         }
474 
475         /* Handle Ethernet checksum */
476         if (!(s->regs[SONIC_TCR] & SONIC_TCR_CRCI)) {
477             /*
478              * Don't append FCS there, to look like slirp packets
479              * which don't have one
480              */
481         } else {
482             /* Remove existing FCS */
483             tx_len -= 4;
484             if (tx_len < 0) {
485                 trace_dp8393x_transmit_txlen_error(tx_len);
486                 break;
487             }
488         }
489 
490         if (s->regs[SONIC_RCR] & (SONIC_RCR_LB1 | SONIC_RCR_LB0)) {
491             /* Loopback */
492             s->regs[SONIC_TCR] |= SONIC_TCR_CRSL;
493             if (nc->info->can_receive(nc)) {
494                 s->loopback_packet = 1;
495                 qemu_receive_packet(nc, s->tx_buffer, tx_len);
496             }
497         } else {
498             /* Transmit packet */
499             qemu_send_packet(nc, s->tx_buffer, tx_len);
500         }
501         s->regs[SONIC_TCR] |= SONIC_TCR_PTX;
502 
503         /* Write status */
504         dp8393x_put(s, width, 0,
505                     s->regs[SONIC_TCR] & 0x0fff); /* status */
506         size = sizeof(uint16_t) * width;
507         address_space_write(&s->as, dp8393x_ttda(s),
508                             MEMTXATTRS_UNSPECIFIED, s->data, size);
509 
510         if (!(s->regs[SONIC_CR] & SONIC_CR_HTX)) {
511             /* Read footer of packet */
512             size = sizeof(uint16_t) * width;
513             address_space_read(&s->as,
514                                dp8393x_ttda(s)
515                                + sizeof(uint16_t) * width
516                                  * (4 + 3 * s->regs[SONIC_TFC]),
517                                MEMTXATTRS_UNSPECIFIED, s->data,
518                                size);
519             s->regs[SONIC_CTDA] = dp8393x_get(s, width, 0);
520             if (s->regs[SONIC_CTDA] & SONIC_DESC_EOL) {
521                 /* EOL detected */
522                 break;
523             }
524         }
525     }
526 
527     /* Done */
528     s->regs[SONIC_CR] &= ~SONIC_CR_TXP;
529     s->regs[SONIC_ISR] |= SONIC_ISR_TXDN;
530     dp8393x_update_irq(s);
531 }
532 
533 static void dp8393x_do_halt_transmission(dp8393xState *s)
534 {
535     /* Nothing to do */
536 }
537 
538 static void dp8393x_do_command(dp8393xState *s, uint16_t command)
539 {
540     if ((s->regs[SONIC_CR] & SONIC_CR_RST) && !(command & SONIC_CR_RST)) {
541         s->regs[SONIC_CR] &= ~SONIC_CR_RST;
542         return;
543     }
544 
545     s->regs[SONIC_CR] |= (command & SONIC_CR_MASK);
546 
547     if (command & SONIC_CR_HTX) {
548         dp8393x_do_halt_transmission(s);
549     }
550     if (command & SONIC_CR_TXP) {
551         dp8393x_do_transmit_packets(s);
552     }
553     if (command & SONIC_CR_RXDIS) {
554         dp8393x_do_receiver_disable(s);
555     }
556     if (command & SONIC_CR_RXEN) {
557         dp8393x_do_receiver_enable(s);
558     }
559     if (command & SONIC_CR_STP) {
560         dp8393x_do_stop_timer(s);
561     }
562     if (command & SONIC_CR_ST) {
563         dp8393x_do_start_timer(s);
564     }
565     if (command & SONIC_CR_RST) {
566         dp8393x_do_software_reset(s);
567     }
568     if (command & SONIC_CR_RRRA) {
569         dp8393x_do_read_rra(s);
570         s->regs[SONIC_CR] &= ~SONIC_CR_RRRA;
571     }
572     if (command & SONIC_CR_LCAM) {
573         dp8393x_do_load_cam(s);
574     }
575 }
576 
577 static uint64_t dp8393x_read(void *opaque, hwaddr addr, unsigned int size)
578 {
579     dp8393xState *s = opaque;
580     int reg = addr >> s->it_shift;
581     uint16_t val = 0;
582 
583     switch (reg) {
584     /* Update data before reading it */
585     case SONIC_WT0:
586     case SONIC_WT1:
587         dp8393x_update_wt_regs(s);
588         val = s->regs[reg];
589         break;
590     /* Accept read to some registers only when in reset mode */
591     case SONIC_CAP2:
592     case SONIC_CAP1:
593     case SONIC_CAP0:
594         if (s->regs[SONIC_CR] & SONIC_CR_RST) {
595             val = s->cam[s->regs[SONIC_CEP] & 0xf][2 * (SONIC_CAP0 - reg) + 1] << 8;
596             val |= s->cam[s->regs[SONIC_CEP] & 0xf][2 * (SONIC_CAP0 - reg)];
597         }
598         break;
599     /* All other registers have no special contraints */
600     default:
601         val = s->regs[reg];
602     }
603 
604     trace_dp8393x_read(reg, reg_names[reg], val, size);
605 
606     return s->big_endian ? val << 16 : val;
607 }
608 
609 static void dp8393x_write(void *opaque, hwaddr addr, uint64_t data,
610                           unsigned int size)
611 {
612     dp8393xState *s = opaque;
613     int reg = addr >> s->it_shift;
614     uint32_t val = s->big_endian ? data >> 16 : data;
615 
616     trace_dp8393x_write(reg, reg_names[reg], val, size);
617 
618     switch (reg) {
619     /* Command register */
620     case SONIC_CR:
621         dp8393x_do_command(s, val);
622         break;
623     /* Prevent write to read-only registers */
624     case SONIC_CAP2:
625     case SONIC_CAP1:
626     case SONIC_CAP0:
627     case SONIC_SR:
628     case SONIC_MDT:
629         trace_dp8393x_write_invalid(reg);
630         break;
631     /* Accept write to some registers only when in reset mode */
632     case SONIC_DCR:
633         if (s->regs[SONIC_CR] & SONIC_CR_RST) {
634             s->regs[reg] = val & 0xbfff;
635         } else {
636             trace_dp8393x_write_invalid_dcr("DCR");
637         }
638         break;
639     case SONIC_DCR2:
640         if (s->regs[SONIC_CR] & SONIC_CR_RST) {
641             s->regs[reg] = val & 0xf017;
642         } else {
643             trace_dp8393x_write_invalid_dcr("DCR2");
644         }
645         break;
646     /* 12 lower bytes are Read Only */
647     case SONIC_TCR:
648         s->regs[reg] = val & 0xf000;
649         break;
650     /* 9 lower bytes are Read Only */
651     case SONIC_RCR:
652         s->regs[reg] = val & 0xffe0;
653         break;
654     /* Ignore most significant bit */
655     case SONIC_IMR:
656         s->regs[reg] = val & 0x7fff;
657         dp8393x_update_irq(s);
658         break;
659     /* Clear bits by writing 1 to them */
660     case SONIC_ISR:
661         val &= s->regs[reg];
662         s->regs[reg] &= ~val;
663         if (val & SONIC_ISR_RBE) {
664             dp8393x_do_read_rra(s);
665         }
666         dp8393x_update_irq(s);
667         break;
668     /* The guest is required to store aligned pointers here */
669     case SONIC_RSA:
670     case SONIC_REA:
671     case SONIC_RRP:
672     case SONIC_RWP:
673         if (s->regs[SONIC_DCR] & SONIC_DCR_DW) {
674             s->regs[reg] = val & 0xfffc;
675         } else {
676             s->regs[reg] = val & 0xfffe;
677         }
678         break;
679     /* Invert written value for some registers */
680     case SONIC_CRCT:
681     case SONIC_FAET:
682     case SONIC_MPT:
683         s->regs[reg] = val ^ 0xffff;
684         break;
685     /* All other registers have no special contrainst */
686     default:
687         s->regs[reg] = val;
688     }
689 
690     if (reg == SONIC_WT0 || reg == SONIC_WT1) {
691         dp8393x_set_next_tick(s);
692     }
693 }
694 
695 static const MemoryRegionOps dp8393x_ops = {
696     .read = dp8393x_read,
697     .write = dp8393x_write,
698     .impl.min_access_size = 4,
699     .impl.max_access_size = 4,
700     .endianness = DEVICE_NATIVE_ENDIAN,
701 };
702 
703 static void dp8393x_watchdog(void *opaque)
704 {
705     dp8393xState *s = opaque;
706 
707     if (s->regs[SONIC_CR] & SONIC_CR_STP) {
708         return;
709     }
710 
711     s->regs[SONIC_WT1] = 0xffff;
712     s->regs[SONIC_WT0] = 0xffff;
713     dp8393x_set_next_tick(s);
714 
715     /* Signal underflow */
716     s->regs[SONIC_ISR] |= SONIC_ISR_TC;
717     dp8393x_update_irq(s);
718 }
719 
720 static bool dp8393x_can_receive(NetClientState *nc)
721 {
722     dp8393xState *s = qemu_get_nic_opaque(nc);
723 
724     return !!(s->regs[SONIC_CR] & SONIC_CR_RXEN);
725 }
726 
727 static int dp8393x_receive_filter(dp8393xState *s, const uint8_t * buf,
728                                   int size)
729 {
730     static const uint8_t bcast[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
731     int i;
732 
733     /* Check promiscuous mode */
734     if ((s->regs[SONIC_RCR] & SONIC_RCR_PRO) && (buf[0] & 1) == 0) {
735         return 0;
736     }
737 
738     /* Check multicast packets */
739     if ((s->regs[SONIC_RCR] & SONIC_RCR_AMC) && (buf[0] & 1) == 1) {
740         return SONIC_RCR_MC;
741     }
742 
743     /* Check broadcast */
744     if ((s->regs[SONIC_RCR] & SONIC_RCR_BRD) &&
745          !memcmp(buf, bcast, sizeof(bcast))) {
746         return SONIC_RCR_BC;
747     }
748 
749     /* Check CAM */
750     for (i = 0; i < 16; i++) {
751         if (s->regs[SONIC_CE] & (1 << i)) {
752             /* Entry enabled */
753             if (!memcmp(buf, s->cam[i], sizeof(s->cam[i]))) {
754                 return 0;
755             }
756         }
757     }
758 
759     return -1;
760 }
761 
762 static ssize_t dp8393x_receive(NetClientState *nc, const uint8_t * buf,
763                                size_t pkt_size)
764 {
765     dp8393xState *s = qemu_get_nic_opaque(nc);
766     int packet_type;
767     uint32_t available, address;
768     int width, rx_len, padded_len;
769     uint32_t checksum;
770     int size;
771 
772     s->regs[SONIC_RCR] &= ~(SONIC_RCR_PRX | SONIC_RCR_LBK | SONIC_RCR_FAER |
773         SONIC_RCR_CRCR | SONIC_RCR_LPKT | SONIC_RCR_BC | SONIC_RCR_MC);
774 
775     if (s->last_rba_is_full) {
776         return pkt_size;
777     }
778 
779     rx_len = pkt_size + sizeof(checksum);
780     if (s->regs[SONIC_DCR] & SONIC_DCR_DW) {
781         width = 2;
782         padded_len = ((rx_len - 1) | 3) + 1;
783     } else {
784         width = 1;
785         padded_len = ((rx_len - 1) | 1) + 1;
786     }
787 
788     if (padded_len > dp8393x_rbwc(s) * 2) {
789         trace_dp8393x_receive_oversize(pkt_size);
790         s->regs[SONIC_ISR] |= SONIC_ISR_RBAE;
791         dp8393x_update_irq(s);
792         s->regs[SONIC_RCR] |= SONIC_RCR_LPKT;
793         goto done;
794     }
795 
796     packet_type = dp8393x_receive_filter(s, buf, pkt_size);
797     if (packet_type < 0) {
798         trace_dp8393x_receive_not_netcard();
799         return -1;
800     }
801 
802     /* Check for EOL */
803     if (s->regs[SONIC_LLFA] & SONIC_DESC_EOL) {
804         /* Are we still in resource exhaustion? */
805         size = sizeof(uint16_t) * 1 * width;
806         address = dp8393x_crda(s) + sizeof(uint16_t) * 5 * width;
807         address_space_read(&s->as, address, MEMTXATTRS_UNSPECIFIED,
808                            s->data, size);
809         s->regs[SONIC_LLFA] = dp8393x_get(s, width, 0);
810         if (s->regs[SONIC_LLFA] & SONIC_DESC_EOL) {
811             /* Still EOL ; stop reception */
812             return -1;
813         }
814         /* Link has been updated by host */
815 
816         /* Clear in_use */
817         size = sizeof(uint16_t) * width;
818         address = dp8393x_crda(s) + sizeof(uint16_t) * 6 * width;
819         dp8393x_put(s, width, 0, 0);
820         address_space_write(&s->as, address, MEMTXATTRS_UNSPECIFIED,
821                             s->data, size);
822 
823         /* Move to next descriptor */
824         s->regs[SONIC_CRDA] = s->regs[SONIC_LLFA];
825         s->regs[SONIC_ISR] |= SONIC_ISR_PKTRX;
826     }
827 
828     /* Save current position */
829     s->regs[SONIC_TRBA1] = s->regs[SONIC_CRBA1];
830     s->regs[SONIC_TRBA0] = s->regs[SONIC_CRBA0];
831 
832     /* Calculate the ethernet checksum */
833     checksum = cpu_to_le32(crc32(0, buf, pkt_size));
834 
835     /* Put packet into RBA */
836     trace_dp8393x_receive_packet(dp8393x_crba(s));
837     address = dp8393x_crba(s);
838     address_space_write(&s->as, address, MEMTXATTRS_UNSPECIFIED,
839                         buf, pkt_size);
840     address += pkt_size;
841 
842     /* Put frame checksum into RBA */
843     address_space_write(&s->as, address, MEMTXATTRS_UNSPECIFIED,
844                         &checksum, sizeof(checksum));
845     address += sizeof(checksum);
846 
847     /* Pad short packets to keep pointers aligned */
848     if (rx_len < padded_len) {
849         size = padded_len - rx_len;
850         address_space_write(&s->as, address, MEMTXATTRS_UNSPECIFIED,
851                             "\xFF\xFF\xFF", size);
852         address += size;
853     }
854 
855     s->regs[SONIC_CRBA1] = address >> 16;
856     s->regs[SONIC_CRBA0] = address & 0xffff;
857     available = dp8393x_rbwc(s);
858     available -= padded_len >> 1;
859     s->regs[SONIC_RBWC1] = available >> 16;
860     s->regs[SONIC_RBWC0] = available & 0xffff;
861 
862     /* Update status */
863     if (dp8393x_rbwc(s) < s->regs[SONIC_EOBC]) {
864         s->regs[SONIC_RCR] |= SONIC_RCR_LPKT;
865     }
866     s->regs[SONIC_RCR] |= packet_type;
867     s->regs[SONIC_RCR] |= SONIC_RCR_PRX;
868     if (s->loopback_packet) {
869         s->regs[SONIC_RCR] |= SONIC_RCR_LBK;
870         s->loopback_packet = 0;
871     }
872 
873     /* Write status to memory */
874     trace_dp8393x_receive_write_status(dp8393x_crda(s));
875     dp8393x_put(s, width, 0, s->regs[SONIC_RCR]); /* status */
876     dp8393x_put(s, width, 1, rx_len); /* byte count */
877     dp8393x_put(s, width, 2, s->regs[SONIC_TRBA0]); /* pkt_ptr0 */
878     dp8393x_put(s, width, 3, s->regs[SONIC_TRBA1]); /* pkt_ptr1 */
879     dp8393x_put(s, width, 4, s->regs[SONIC_RSC]); /* seq_no */
880     size = sizeof(uint16_t) * 5 * width;
881     address_space_write(&s->as, dp8393x_crda(s),
882                         MEMTXATTRS_UNSPECIFIED,
883                         s->data, size);
884 
885     /* Check link field */
886     size = sizeof(uint16_t) * width;
887     address_space_read(&s->as,
888                        dp8393x_crda(s) + sizeof(uint16_t) * 5 * width,
889                        MEMTXATTRS_UNSPECIFIED, s->data, size);
890     s->regs[SONIC_LLFA] = dp8393x_get(s, width, 0);
891     if (s->regs[SONIC_LLFA] & SONIC_DESC_EOL) {
892         /* EOL detected */
893         s->regs[SONIC_ISR] |= SONIC_ISR_RDE;
894     } else {
895         /* Clear in_use */
896         size = sizeof(uint16_t) * width;
897         address = dp8393x_crda(s) + sizeof(uint16_t) * 6 * width;
898         dp8393x_put(s, width, 0, 0);
899         address_space_write(&s->as, address, MEMTXATTRS_UNSPECIFIED,
900                             s->data, size);
901 
902         /* Move to next descriptor */
903         s->regs[SONIC_CRDA] = s->regs[SONIC_LLFA];
904         s->regs[SONIC_ISR] |= SONIC_ISR_PKTRX;
905     }
906 
907     dp8393x_update_irq(s);
908 
909     s->regs[SONIC_RSC] = (s->regs[SONIC_RSC] & 0xff00) |
910                          ((s->regs[SONIC_RSC] + 1) & 0x00ff);
911 
912 done:
913 
914     if (s->regs[SONIC_RCR] & SONIC_RCR_LPKT) {
915         if (s->regs[SONIC_RRP] == s->regs[SONIC_RWP]) {
916             /* Stop packet reception */
917             s->last_rba_is_full = true;
918         } else {
919             /* Read next resource */
920             dp8393x_do_read_rra(s);
921         }
922     }
923 
924     return pkt_size;
925 }
926 
927 static void dp8393x_reset(DeviceState *dev)
928 {
929     dp8393xState *s = DP8393X(dev);
930     timer_del(s->watchdog);
931 
932     memset(s->regs, 0, sizeof(s->regs));
933     s->regs[SONIC_SR] = 0x0004; /* only revision recognized by Linux/mips */
934     s->regs[SONIC_CR] = SONIC_CR_RST | SONIC_CR_STP | SONIC_CR_RXDIS;
935     s->regs[SONIC_DCR] &= ~(SONIC_DCR_EXBUS | SONIC_DCR_LBR);
936     s->regs[SONIC_RCR] &= ~(SONIC_RCR_LB0 | SONIC_RCR_LB1 | SONIC_RCR_BRD |
937                             SONIC_RCR_RNT);
938     s->regs[SONIC_TCR] |= SONIC_TCR_NCRS | SONIC_TCR_PTX;
939     s->regs[SONIC_TCR] &= ~SONIC_TCR_BCM;
940     s->regs[SONIC_IMR] = 0;
941     s->regs[SONIC_ISR] = 0;
942     s->regs[SONIC_DCR2] = 0;
943     s->regs[SONIC_EOBC] = 0x02F8;
944     s->regs[SONIC_RSC] = 0;
945     s->regs[SONIC_CE] = 0;
946     s->regs[SONIC_RSC] = 0;
947 
948     /* Network cable is connected */
949     s->regs[SONIC_RCR] |= SONIC_RCR_CRS;
950 
951     dp8393x_update_irq(s);
952 }
953 
954 static NetClientInfo net_dp83932_info = {
955     .type = NET_CLIENT_DRIVER_NIC,
956     .size = sizeof(NICState),
957     .can_receive = dp8393x_can_receive,
958     .receive = dp8393x_receive,
959 };
960 
961 static void dp8393x_instance_init(Object *obj)
962 {
963     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
964     dp8393xState *s = DP8393X(obj);
965 
966     sysbus_init_mmio(sbd, &s->mmio);
967     sysbus_init_irq(sbd, &s->irq);
968 }
969 
970 static void dp8393x_realize(DeviceState *dev, Error **errp)
971 {
972     dp8393xState *s = DP8393X(dev);
973 
974     address_space_init(&s->as, s->dma_mr, "dp8393x");
975     memory_region_init_io(&s->mmio, OBJECT(dev), &dp8393x_ops, s,
976                           "dp8393x-regs", SONIC_REG_COUNT << s->it_shift);
977 
978     s->nic = qemu_new_nic(&net_dp83932_info, &s->conf,
979                           object_get_typename(OBJECT(dev)), dev->id, s);
980     qemu_format_nic_info_str(qemu_get_queue(s->nic), s->conf.macaddr.a);
981 
982     s->watchdog = timer_new_ns(QEMU_CLOCK_VIRTUAL, dp8393x_watchdog, s);
983 }
984 
985 static const VMStateDescription vmstate_dp8393x = {
986     .name = "dp8393x",
987     .version_id = 0,
988     .minimum_version_id = 0,
989     .fields = (VMStateField []) {
990         VMSTATE_BUFFER_UNSAFE(cam, dp8393xState, 0, 16 * 6),
991         VMSTATE_UINT16_ARRAY(regs, dp8393xState, SONIC_REG_COUNT),
992         VMSTATE_END_OF_LIST()
993     }
994 };
995 
996 static Property dp8393x_properties[] = {
997     DEFINE_NIC_PROPERTIES(dp8393xState, conf),
998     DEFINE_PROP_LINK("dma_mr", dp8393xState, dma_mr,
999                      TYPE_MEMORY_REGION, MemoryRegion *),
1000     DEFINE_PROP_UINT8("it_shift", dp8393xState, it_shift, 0),
1001     DEFINE_PROP_BOOL("big_endian", dp8393xState, big_endian, false),
1002     DEFINE_PROP_END_OF_LIST(),
1003 };
1004 
1005 static void dp8393x_class_init(ObjectClass *klass, void *data)
1006 {
1007     DeviceClass *dc = DEVICE_CLASS(klass);
1008 
1009     set_bit(DEVICE_CATEGORY_NETWORK, dc->categories);
1010     dc->realize = dp8393x_realize;
1011     dc->reset = dp8393x_reset;
1012     dc->vmsd = &vmstate_dp8393x;
1013     device_class_set_props(dc, dp8393x_properties);
1014 }
1015 
1016 static const TypeInfo dp8393x_info = {
1017     .name          = TYPE_DP8393X,
1018     .parent        = TYPE_SYS_BUS_DEVICE,
1019     .instance_size = sizeof(dp8393xState),
1020     .instance_init = dp8393x_instance_init,
1021     .class_init    = dp8393x_class_init,
1022 };
1023 
1024 static void dp8393x_register_types(void)
1025 {
1026     type_register_static(&dp8393x_info);
1027 }
1028 
1029 type_init(dp8393x_register_types)
1030