xref: /openbmc/qemu/hw/net/dp8393x.c (revision fc8c745d)
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 
89 #define SONIC_CR_HTX     0x0001
90 #define SONIC_CR_TXP     0x0002
91 #define SONIC_CR_RXDIS   0x0004
92 #define SONIC_CR_RXEN    0x0008
93 #define SONIC_CR_STP     0x0010
94 #define SONIC_CR_ST      0x0020
95 #define SONIC_CR_RST     0x0080
96 #define SONIC_CR_RRRA    0x0100
97 #define SONIC_CR_LCAM    0x0200
98 #define SONIC_CR_MASK    0x03bf
99 
100 #define SONIC_DCR_DW     0x0020
101 #define SONIC_DCR_LBR    0x2000
102 #define SONIC_DCR_EXBUS  0x8000
103 
104 #define SONIC_RCR_PRX    0x0001
105 #define SONIC_RCR_LBK    0x0002
106 #define SONIC_RCR_FAER   0x0004
107 #define SONIC_RCR_CRCR   0x0008
108 #define SONIC_RCR_CRS    0x0020
109 #define SONIC_RCR_LPKT   0x0040
110 #define SONIC_RCR_BC     0x0080
111 #define SONIC_RCR_MC     0x0100
112 #define SONIC_RCR_LB0    0x0200
113 #define SONIC_RCR_LB1    0x0400
114 #define SONIC_RCR_AMC    0x0800
115 #define SONIC_RCR_PRO    0x1000
116 #define SONIC_RCR_BRD    0x2000
117 #define SONIC_RCR_RNT    0x4000
118 
119 #define SONIC_TCR_PTX    0x0001
120 #define SONIC_TCR_BCM    0x0002
121 #define SONIC_TCR_FU     0x0004
122 #define SONIC_TCR_EXC    0x0040
123 #define SONIC_TCR_CRSL   0x0080
124 #define SONIC_TCR_NCRS   0x0100
125 #define SONIC_TCR_EXD    0x0400
126 #define SONIC_TCR_CRCI   0x2000
127 #define SONIC_TCR_PINT   0x8000
128 
129 #define SONIC_ISR_RBAE   0x0010
130 #define SONIC_ISR_RBE    0x0020
131 #define SONIC_ISR_RDE    0x0040
132 #define SONIC_ISR_TC     0x0080
133 #define SONIC_ISR_TXDN   0x0200
134 #define SONIC_ISR_PKTRX  0x0400
135 #define SONIC_ISR_PINT   0x0800
136 #define SONIC_ISR_LCD    0x1000
137 
138 #define SONIC_DESC_EOL   0x0001
139 #define SONIC_DESC_ADDR  0xFFFE
140 
141 #define TYPE_DP8393X "dp8393x"
142 OBJECT_DECLARE_SIMPLE_TYPE(dp8393xState, DP8393X)
143 
144 struct dp8393xState {
145     SysBusDevice parent_obj;
146 
147     /* Hardware */
148     uint8_t it_shift;
149     bool big_endian;
150     bool last_rba_is_full;
151     qemu_irq irq;
152     int irq_level;
153     QEMUTimer *watchdog;
154     int64_t wt_last_update;
155     NICConf conf;
156     NICState *nic;
157     MemoryRegion mmio;
158 
159     /* Registers */
160     uint8_t cam[16][6];
161     uint16_t regs[0x40];
162 
163     /* Temporaries */
164     uint8_t tx_buffer[0x10000];
165     uint16_t data[12];
166     int loopback_packet;
167 
168     /* Memory access */
169     MemoryRegion *dma_mr;
170     AddressSpace as;
171 };
172 
173 /*
174  * Accessor functions for values which are formed by
175  * concatenating two 16 bit device registers. By putting these
176  * in their own functions with a uint32_t return type we avoid the
177  * pitfall of implicit sign extension where ((x << 16) | y) is a
178  * signed 32 bit integer that might get sign-extended to a 64 bit integer.
179  */
180 static uint32_t dp8393x_cdp(dp8393xState *s)
181 {
182     return (s->regs[SONIC_URRA] << 16) | s->regs[SONIC_CDP];
183 }
184 
185 static uint32_t dp8393x_crba(dp8393xState *s)
186 {
187     return (s->regs[SONIC_CRBA1] << 16) | s->regs[SONIC_CRBA0];
188 }
189 
190 static uint32_t dp8393x_crda(dp8393xState *s)
191 {
192     return (s->regs[SONIC_URDA] << 16) |
193            (s->regs[SONIC_CRDA] & SONIC_DESC_ADDR);
194 }
195 
196 static uint32_t dp8393x_rbwc(dp8393xState *s)
197 {
198     return (s->regs[SONIC_RBWC1] << 16) | s->regs[SONIC_RBWC0];
199 }
200 
201 static uint32_t dp8393x_rrp(dp8393xState *s)
202 {
203     return (s->regs[SONIC_URRA] << 16) | s->regs[SONIC_RRP];
204 }
205 
206 static uint32_t dp8393x_tsa(dp8393xState *s)
207 {
208     return (s->regs[SONIC_TSA1] << 16) | s->regs[SONIC_TSA0];
209 }
210 
211 static uint32_t dp8393x_ttda(dp8393xState *s)
212 {
213     return (s->regs[SONIC_UTDA] << 16) |
214            (s->regs[SONIC_TTDA] & SONIC_DESC_ADDR);
215 }
216 
217 static uint32_t dp8393x_wt(dp8393xState *s)
218 {
219     return s->regs[SONIC_WT1] << 16 | s->regs[SONIC_WT0];
220 }
221 
222 static uint16_t dp8393x_get(dp8393xState *s, int width, int offset)
223 {
224     uint16_t val;
225 
226     if (s->big_endian) {
227         val = be16_to_cpu(s->data[offset * width + width - 1]);
228     } else {
229         val = le16_to_cpu(s->data[offset * width]);
230     }
231     return val;
232 }
233 
234 static void dp8393x_put(dp8393xState *s, int width, int offset,
235                         uint16_t val)
236 {
237     if (s->big_endian) {
238         if (width == 2) {
239             s->data[offset * 2] = 0;
240             s->data[offset * 2 + 1] = cpu_to_be16(val);
241         } else {
242             s->data[offset] = cpu_to_be16(val);
243         }
244     } else {
245         if (width == 2) {
246             s->data[offset * 2] = cpu_to_le16(val);
247             s->data[offset * 2 + 1] = 0;
248         } else {
249             s->data[offset] = cpu_to_le16(val);
250         }
251     }
252 }
253 
254 static void dp8393x_update_irq(dp8393xState *s)
255 {
256     int level = (s->regs[SONIC_IMR] & s->regs[SONIC_ISR]) ? 1 : 0;
257 
258     if (level != s->irq_level) {
259         s->irq_level = level;
260         if (level) {
261             trace_dp8393x_raise_irq(s->regs[SONIC_ISR]);
262         } else {
263             trace_dp8393x_lower_irq();
264         }
265     }
266 
267     qemu_set_irq(s->irq, level);
268 }
269 
270 static void dp8393x_do_load_cam(dp8393xState *s)
271 {
272     int width, size;
273     uint16_t index = 0;
274 
275     width = (s->regs[SONIC_DCR] & SONIC_DCR_DW) ? 2 : 1;
276     size = sizeof(uint16_t) * 4 * width;
277 
278     while (s->regs[SONIC_CDC] & 0x1f) {
279         /* Fill current entry */
280         address_space_read(&s->as, dp8393x_cdp(s),
281                            MEMTXATTRS_UNSPECIFIED, s->data, size);
282         s->cam[index][0] = dp8393x_get(s, width, 1) & 0xff;
283         s->cam[index][1] = dp8393x_get(s, width, 1) >> 8;
284         s->cam[index][2] = dp8393x_get(s, width, 2) & 0xff;
285         s->cam[index][3] = dp8393x_get(s, width, 2) >> 8;
286         s->cam[index][4] = dp8393x_get(s, width, 3) & 0xff;
287         s->cam[index][5] = dp8393x_get(s, width, 3) >> 8;
288         trace_dp8393x_load_cam(index, s->cam[index][0], s->cam[index][1],
289                                s->cam[index][2], s->cam[index][3],
290                                s->cam[index][4], s->cam[index][5]);
291         /* Move to next entry */
292         s->regs[SONIC_CDC]--;
293         s->regs[SONIC_CDP] += size;
294         index++;
295     }
296 
297     /* Read CAM enable */
298     address_space_read(&s->as, dp8393x_cdp(s),
299                        MEMTXATTRS_UNSPECIFIED, s->data, size);
300     s->regs[SONIC_CE] = dp8393x_get(s, width, 0);
301     trace_dp8393x_load_cam_done(s->regs[SONIC_CE]);
302 
303     /* Done */
304     s->regs[SONIC_CR] &= ~SONIC_CR_LCAM;
305     s->regs[SONIC_ISR] |= SONIC_ISR_LCD;
306     dp8393x_update_irq(s);
307 }
308 
309 static void dp8393x_do_read_rra(dp8393xState *s)
310 {
311     int width, size;
312 
313     /* Read memory */
314     width = (s->regs[SONIC_DCR] & SONIC_DCR_DW) ? 2 : 1;
315     size = sizeof(uint16_t) * 4 * width;
316     address_space_read(&s->as, dp8393x_rrp(s),
317                        MEMTXATTRS_UNSPECIFIED, s->data, size);
318 
319     /* Update SONIC registers */
320     s->regs[SONIC_CRBA0] = dp8393x_get(s, width, 0);
321     s->regs[SONIC_CRBA1] = dp8393x_get(s, width, 1);
322     s->regs[SONIC_RBWC0] = dp8393x_get(s, width, 2);
323     s->regs[SONIC_RBWC1] = dp8393x_get(s, width, 3);
324     trace_dp8393x_read_rra_regs(s->regs[SONIC_CRBA0], s->regs[SONIC_CRBA1],
325                                 s->regs[SONIC_RBWC0], s->regs[SONIC_RBWC1]);
326 
327     /* Go to next entry */
328     s->regs[SONIC_RRP] += size;
329 
330     /* Handle wrap */
331     if (s->regs[SONIC_RRP] == s->regs[SONIC_REA]) {
332         s->regs[SONIC_RRP] = s->regs[SONIC_RSA];
333     }
334 
335     /* Warn the host if CRBA now has the last available resource */
336     if (s->regs[SONIC_RRP] == s->regs[SONIC_RWP]) {
337         s->regs[SONIC_ISR] |= SONIC_ISR_RBE;
338         dp8393x_update_irq(s);
339     }
340 
341     /* Allow packet reception */
342     s->last_rba_is_full = false;
343 }
344 
345 static void dp8393x_do_software_reset(dp8393xState *s)
346 {
347     timer_del(s->watchdog);
348 
349     s->regs[SONIC_CR] &= ~(SONIC_CR_LCAM | SONIC_CR_RRRA | SONIC_CR_TXP |
350                            SONIC_CR_HTX);
351     s->regs[SONIC_CR] |= SONIC_CR_RST | SONIC_CR_RXDIS;
352 }
353 
354 static void dp8393x_set_next_tick(dp8393xState *s)
355 {
356     uint32_t ticks;
357     int64_t delay;
358 
359     if (s->regs[SONIC_CR] & SONIC_CR_STP) {
360         timer_del(s->watchdog);
361         return;
362     }
363 
364     ticks = dp8393x_wt(s);
365     s->wt_last_update = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
366     delay = NANOSECONDS_PER_SECOND * ticks / 5000000;
367     timer_mod(s->watchdog, s->wt_last_update + delay);
368 }
369 
370 static void dp8393x_update_wt_regs(dp8393xState *s)
371 {
372     int64_t elapsed;
373     uint32_t val;
374 
375     if (s->regs[SONIC_CR] & SONIC_CR_STP) {
376         timer_del(s->watchdog);
377         return;
378     }
379 
380     elapsed = s->wt_last_update - qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
381     val = dp8393x_wt(s);
382     val -= elapsed / 5000000;
383     s->regs[SONIC_WT1] = (val >> 16) & 0xffff;
384     s->regs[SONIC_WT0] = (val >> 0)  & 0xffff;
385     dp8393x_set_next_tick(s);
386 
387 }
388 
389 static void dp8393x_do_start_timer(dp8393xState *s)
390 {
391     s->regs[SONIC_CR] &= ~SONIC_CR_STP;
392     dp8393x_set_next_tick(s);
393 }
394 
395 static void dp8393x_do_stop_timer(dp8393xState *s)
396 {
397     s->regs[SONIC_CR] &= ~SONIC_CR_ST;
398     dp8393x_update_wt_regs(s);
399 }
400 
401 static bool dp8393x_can_receive(NetClientState *nc);
402 
403 static void dp8393x_do_receiver_enable(dp8393xState *s)
404 {
405     s->regs[SONIC_CR] &= ~SONIC_CR_RXDIS;
406     if (dp8393x_can_receive(s->nic->ncs)) {
407         qemu_flush_queued_packets(qemu_get_queue(s->nic));
408     }
409 }
410 
411 static void dp8393x_do_receiver_disable(dp8393xState *s)
412 {
413     s->regs[SONIC_CR] &= ~SONIC_CR_RXEN;
414 }
415 
416 static void dp8393x_do_transmit_packets(dp8393xState *s)
417 {
418     NetClientState *nc = qemu_get_queue(s->nic);
419     int width, size;
420     int tx_len, len;
421     uint16_t i;
422 
423     width = (s->regs[SONIC_DCR] & SONIC_DCR_DW) ? 2 : 1;
424 
425     while (1) {
426         /* Read memory */
427         size = sizeof(uint16_t) * 6 * width;
428         s->regs[SONIC_TTDA] = s->regs[SONIC_CTDA];
429         trace_dp8393x_transmit_packet(dp8393x_ttda(s));
430         address_space_read(&s->as, dp8393x_ttda(s) + sizeof(uint16_t) * width,
431                            MEMTXATTRS_UNSPECIFIED, s->data, size);
432         tx_len = 0;
433 
434         /* Update registers */
435         s->regs[SONIC_TCR] = dp8393x_get(s, width, 0) & 0xf000;
436         s->regs[SONIC_TPS] = dp8393x_get(s, width, 1);
437         s->regs[SONIC_TFC] = dp8393x_get(s, width, 2);
438         s->regs[SONIC_TSA0] = dp8393x_get(s, width, 3);
439         s->regs[SONIC_TSA1] = dp8393x_get(s, width, 4);
440         s->regs[SONIC_TFS] = dp8393x_get(s, width, 5);
441 
442         /* Handle programmable interrupt */
443         if (s->regs[SONIC_TCR] & SONIC_TCR_PINT) {
444             s->regs[SONIC_ISR] |= SONIC_ISR_PINT;
445         } else {
446             s->regs[SONIC_ISR] &= ~SONIC_ISR_PINT;
447         }
448 
449         for (i = 0; i < s->regs[SONIC_TFC]; ) {
450             /* Append fragment */
451             len = s->regs[SONIC_TFS];
452             if (tx_len + len > sizeof(s->tx_buffer)) {
453                 len = sizeof(s->tx_buffer) - tx_len;
454             }
455             address_space_read(&s->as, dp8393x_tsa(s), MEMTXATTRS_UNSPECIFIED,
456                                &s->tx_buffer[tx_len], len);
457             tx_len += len;
458 
459             i++;
460             if (i != s->regs[SONIC_TFC]) {
461                 /* Read next fragment details */
462                 size = sizeof(uint16_t) * 3 * width;
463                 address_space_read(&s->as,
464                                    dp8393x_ttda(s)
465                                    + sizeof(uint16_t) * width * (4 + 3 * i),
466                                    MEMTXATTRS_UNSPECIFIED, s->data,
467                                    size);
468                 s->regs[SONIC_TSA0] = dp8393x_get(s, width, 0);
469                 s->regs[SONIC_TSA1] = dp8393x_get(s, width, 1);
470                 s->regs[SONIC_TFS] = dp8393x_get(s, width, 2);
471             }
472         }
473 
474         /* Handle Ethernet checksum */
475         if (!(s->regs[SONIC_TCR] & SONIC_TCR_CRCI)) {
476             /*
477              * Don't append FCS there, to look like slirp packets
478              * which don't have one
479              */
480         } else {
481             /* Remove existing FCS */
482             tx_len -= 4;
483             if (tx_len < 0) {
484                 trace_dp8393x_transmit_txlen_error(tx_len);
485                 break;
486             }
487         }
488 
489         if (s->regs[SONIC_RCR] & (SONIC_RCR_LB1 | SONIC_RCR_LB0)) {
490             /* Loopback */
491             s->regs[SONIC_TCR] |= SONIC_TCR_CRSL;
492             if (nc->info->can_receive(nc)) {
493                 s->loopback_packet = 1;
494                 qemu_receive_packet(nc, s->tx_buffer, tx_len);
495             }
496         } else {
497             /* Transmit packet */
498             qemu_send_packet(nc, s->tx_buffer, tx_len);
499         }
500         s->regs[SONIC_TCR] |= SONIC_TCR_PTX;
501 
502         /* Write status */
503         dp8393x_put(s, width, 0,
504                     s->regs[SONIC_TCR] & 0x0fff); /* status */
505         size = sizeof(uint16_t) * width;
506         address_space_write(&s->as, dp8393x_ttda(s),
507                             MEMTXATTRS_UNSPECIFIED, s->data, size);
508 
509         if (!(s->regs[SONIC_CR] & SONIC_CR_HTX)) {
510             /* Read footer of packet */
511             size = sizeof(uint16_t) * width;
512             address_space_read(&s->as,
513                                dp8393x_ttda(s)
514                                + sizeof(uint16_t) * width
515                                  * (4 + 3 * s->regs[SONIC_TFC]),
516                                MEMTXATTRS_UNSPECIFIED, s->data,
517                                size);
518             s->regs[SONIC_CTDA] = dp8393x_get(s, width, 0);
519             if (s->regs[SONIC_CTDA] & SONIC_DESC_EOL) {
520                 /* EOL detected */
521                 break;
522             }
523         }
524     }
525 
526     /* Done */
527     s->regs[SONIC_CR] &= ~SONIC_CR_TXP;
528     s->regs[SONIC_ISR] |= SONIC_ISR_TXDN;
529     dp8393x_update_irq(s);
530 }
531 
532 static void dp8393x_do_halt_transmission(dp8393xState *s)
533 {
534     /* Nothing to do */
535 }
536 
537 static void dp8393x_do_command(dp8393xState *s, uint16_t command)
538 {
539     if ((s->regs[SONIC_CR] & SONIC_CR_RST) && !(command & SONIC_CR_RST)) {
540         s->regs[SONIC_CR] &= ~SONIC_CR_RST;
541         return;
542     }
543 
544     s->regs[SONIC_CR] |= (command & SONIC_CR_MASK);
545 
546     if (command & SONIC_CR_HTX) {
547         dp8393x_do_halt_transmission(s);
548     }
549     if (command & SONIC_CR_TXP) {
550         dp8393x_do_transmit_packets(s);
551     }
552     if (command & SONIC_CR_RXDIS) {
553         dp8393x_do_receiver_disable(s);
554     }
555     if (command & SONIC_CR_RXEN) {
556         dp8393x_do_receiver_enable(s);
557     }
558     if (command & SONIC_CR_STP) {
559         dp8393x_do_stop_timer(s);
560     }
561     if (command & SONIC_CR_ST) {
562         dp8393x_do_start_timer(s);
563     }
564     if (command & SONIC_CR_RST) {
565         dp8393x_do_software_reset(s);
566     }
567     if (command & SONIC_CR_RRRA) {
568         dp8393x_do_read_rra(s);
569         s->regs[SONIC_CR] &= ~SONIC_CR_RRRA;
570     }
571     if (command & SONIC_CR_LCAM) {
572         dp8393x_do_load_cam(s);
573     }
574 }
575 
576 static uint64_t dp8393x_read(void *opaque, hwaddr addr, unsigned int size)
577 {
578     dp8393xState *s = opaque;
579     int reg = addr >> s->it_shift;
580     uint16_t val = 0;
581 
582     switch (reg) {
583     /* Update data before reading it */
584     case SONIC_WT0:
585     case SONIC_WT1:
586         dp8393x_update_wt_regs(s);
587         val = s->regs[reg];
588         break;
589     /* Accept read to some registers only when in reset mode */
590     case SONIC_CAP2:
591     case SONIC_CAP1:
592     case SONIC_CAP0:
593         if (s->regs[SONIC_CR] & SONIC_CR_RST) {
594             val = s->cam[s->regs[SONIC_CEP] & 0xf][2 * (SONIC_CAP0 - reg) + 1] << 8;
595             val |= s->cam[s->regs[SONIC_CEP] & 0xf][2 * (SONIC_CAP0 - reg)];
596         }
597         break;
598     /* All other registers have no special contraints */
599     default:
600         val = s->regs[reg];
601     }
602 
603     trace_dp8393x_read(reg, reg_names[reg], val, size);
604 
605     return s->big_endian ? val << 16 : val;
606 }
607 
608 static void dp8393x_write(void *opaque, hwaddr addr, uint64_t data,
609                           unsigned int size)
610 {
611     dp8393xState *s = opaque;
612     int reg = addr >> s->it_shift;
613     uint32_t val = s->big_endian ? data >> 16 : data;
614 
615     trace_dp8393x_write(reg, reg_names[reg], val, size);
616 
617     switch (reg) {
618     /* Command register */
619     case SONIC_CR:
620         dp8393x_do_command(s, val);
621         break;
622     /* Prevent write to read-only registers */
623     case SONIC_CAP2:
624     case SONIC_CAP1:
625     case SONIC_CAP0:
626     case SONIC_SR:
627     case SONIC_MDT:
628         trace_dp8393x_write_invalid(reg);
629         break;
630     /* Accept write to some registers only when in reset mode */
631     case SONIC_DCR:
632         if (s->regs[SONIC_CR] & SONIC_CR_RST) {
633             s->regs[reg] = val & 0xbfff;
634         } else {
635             trace_dp8393x_write_invalid_dcr("DCR");
636         }
637         break;
638     case SONIC_DCR2:
639         if (s->regs[SONIC_CR] & SONIC_CR_RST) {
640             s->regs[reg] = val & 0xf017;
641         } else {
642             trace_dp8393x_write_invalid_dcr("DCR2");
643         }
644         break;
645     /* 12 lower bytes are Read Only */
646     case SONIC_TCR:
647         s->regs[reg] = val & 0xf000;
648         break;
649     /* 9 lower bytes are Read Only */
650     case SONIC_RCR:
651         s->regs[reg] = val & 0xffe0;
652         break;
653     /* Ignore most significant bit */
654     case SONIC_IMR:
655         s->regs[reg] = val & 0x7fff;
656         dp8393x_update_irq(s);
657         break;
658     /* Clear bits by writing 1 to them */
659     case SONIC_ISR:
660         val &= s->regs[reg];
661         s->regs[reg] &= ~val;
662         if (val & SONIC_ISR_RBE) {
663             dp8393x_do_read_rra(s);
664         }
665         dp8393x_update_irq(s);
666         break;
667     /* The guest is required to store aligned pointers here */
668     case SONIC_RSA:
669     case SONIC_REA:
670     case SONIC_RRP:
671     case SONIC_RWP:
672         if (s->regs[SONIC_DCR] & SONIC_DCR_DW) {
673             s->regs[reg] = val & 0xfffc;
674         } else {
675             s->regs[reg] = val & 0xfffe;
676         }
677         break;
678     /* Invert written value for some registers */
679     case SONIC_CRCT:
680     case SONIC_FAET:
681     case SONIC_MPT:
682         s->regs[reg] = val ^ 0xffff;
683         break;
684     /* All other registers have no special contrainst */
685     default:
686         s->regs[reg] = val;
687     }
688 
689     if (reg == SONIC_WT0 || reg == SONIC_WT1) {
690         dp8393x_set_next_tick(s);
691     }
692 }
693 
694 static const MemoryRegionOps dp8393x_ops = {
695     .read = dp8393x_read,
696     .write = dp8393x_write,
697     .impl.min_access_size = 4,
698     .impl.max_access_size = 4,
699     .endianness = DEVICE_NATIVE_ENDIAN,
700 };
701 
702 static void dp8393x_watchdog(void *opaque)
703 {
704     dp8393xState *s = opaque;
705 
706     if (s->regs[SONIC_CR] & SONIC_CR_STP) {
707         return;
708     }
709 
710     s->regs[SONIC_WT1] = 0xffff;
711     s->regs[SONIC_WT0] = 0xffff;
712     dp8393x_set_next_tick(s);
713 
714     /* Signal underflow */
715     s->regs[SONIC_ISR] |= SONIC_ISR_TC;
716     dp8393x_update_irq(s);
717 }
718 
719 static bool dp8393x_can_receive(NetClientState *nc)
720 {
721     dp8393xState *s = qemu_get_nic_opaque(nc);
722 
723     return !!(s->regs[SONIC_CR] & SONIC_CR_RXEN);
724 }
725 
726 static int dp8393x_receive_filter(dp8393xState *s, const uint8_t * buf,
727                                   int size)
728 {
729     static const uint8_t bcast[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
730     int i;
731 
732     /* Check promiscuous mode */
733     if ((s->regs[SONIC_RCR] & SONIC_RCR_PRO) && (buf[0] & 1) == 0) {
734         return 0;
735     }
736 
737     /* Check multicast packets */
738     if ((s->regs[SONIC_RCR] & SONIC_RCR_AMC) && (buf[0] & 1) == 1) {
739         return SONIC_RCR_MC;
740     }
741 
742     /* Check broadcast */
743     if ((s->regs[SONIC_RCR] & SONIC_RCR_BRD) &&
744          !memcmp(buf, bcast, sizeof(bcast))) {
745         return SONIC_RCR_BC;
746     }
747 
748     /* Check CAM */
749     for (i = 0; i < 16; i++) {
750         if (s->regs[SONIC_CE] & (1 << i)) {
751             /* Entry enabled */
752             if (!memcmp(buf, s->cam[i], sizeof(s->cam[i]))) {
753                 return 0;
754             }
755         }
756     }
757 
758     return -1;
759 }
760 
761 static ssize_t dp8393x_receive(NetClientState *nc, const uint8_t * buf,
762                                size_t pkt_size)
763 {
764     dp8393xState *s = qemu_get_nic_opaque(nc);
765     int packet_type;
766     uint32_t available, address;
767     int width, rx_len, padded_len;
768     uint32_t checksum;
769     int size;
770 
771     s->regs[SONIC_RCR] &= ~(SONIC_RCR_PRX | SONIC_RCR_LBK | SONIC_RCR_FAER |
772         SONIC_RCR_CRCR | SONIC_RCR_LPKT | SONIC_RCR_BC | SONIC_RCR_MC);
773 
774     if (s->last_rba_is_full) {
775         return pkt_size;
776     }
777 
778     rx_len = pkt_size + sizeof(checksum);
779     if (s->regs[SONIC_DCR] & SONIC_DCR_DW) {
780         width = 2;
781         padded_len = ((rx_len - 1) | 3) + 1;
782     } else {
783         width = 1;
784         padded_len = ((rx_len - 1) | 1) + 1;
785     }
786 
787     if (padded_len > dp8393x_rbwc(s) * 2) {
788         trace_dp8393x_receive_oversize(pkt_size);
789         s->regs[SONIC_ISR] |= SONIC_ISR_RBAE;
790         dp8393x_update_irq(s);
791         s->regs[SONIC_RCR] |= SONIC_RCR_LPKT;
792         goto done;
793     }
794 
795     packet_type = dp8393x_receive_filter(s, buf, pkt_size);
796     if (packet_type < 0) {
797         trace_dp8393x_receive_not_netcard();
798         return -1;
799     }
800 
801     /* Check for EOL */
802     if (s->regs[SONIC_LLFA] & SONIC_DESC_EOL) {
803         /* Are we still in resource exhaustion? */
804         size = sizeof(uint16_t) * 1 * width;
805         address = dp8393x_crda(s) + sizeof(uint16_t) * 5 * width;
806         address_space_read(&s->as, address, MEMTXATTRS_UNSPECIFIED,
807                            s->data, size);
808         s->regs[SONIC_LLFA] = dp8393x_get(s, width, 0);
809         if (s->regs[SONIC_LLFA] & SONIC_DESC_EOL) {
810             /* Still EOL ; stop reception */
811             return -1;
812         }
813         /* Link has been updated by host */
814 
815         /* Clear in_use */
816         size = sizeof(uint16_t) * width;
817         address = dp8393x_crda(s) + sizeof(uint16_t) * 6 * width;
818         dp8393x_put(s, width, 0, 0);
819         address_space_rw(&s->as, address, MEMTXATTRS_UNSPECIFIED,
820                          (uint8_t *)s->data, size, 1);
821 
822         /* Move to next descriptor */
823         s->regs[SONIC_CRDA] = s->regs[SONIC_LLFA];
824         s->regs[SONIC_ISR] |= SONIC_ISR_PKTRX;
825     }
826 
827     /* Save current position */
828     s->regs[SONIC_TRBA1] = s->regs[SONIC_CRBA1];
829     s->regs[SONIC_TRBA0] = s->regs[SONIC_CRBA0];
830 
831     /* Calculate the ethernet checksum */
832     checksum = cpu_to_le32(crc32(0, buf, pkt_size));
833 
834     /* Put packet into RBA */
835     trace_dp8393x_receive_packet(dp8393x_crba(s));
836     address = dp8393x_crba(s);
837     address_space_write(&s->as, address, MEMTXATTRS_UNSPECIFIED,
838                         buf, pkt_size);
839     address += pkt_size;
840 
841     /* Put frame checksum into RBA */
842     address_space_write(&s->as, address, MEMTXATTRS_UNSPECIFIED,
843                         &checksum, sizeof(checksum));
844     address += sizeof(checksum);
845 
846     /* Pad short packets to keep pointers aligned */
847     if (rx_len < padded_len) {
848         size = padded_len - rx_len;
849         address_space_rw(&s->as, address, MEMTXATTRS_UNSPECIFIED,
850             (uint8_t *)"\xFF\xFF\xFF", size, 1);
851         address += size;
852     }
853 
854     s->regs[SONIC_CRBA1] = address >> 16;
855     s->regs[SONIC_CRBA0] = address & 0xffff;
856     available = dp8393x_rbwc(s);
857     available -= padded_len >> 1;
858     s->regs[SONIC_RBWC1] = available >> 16;
859     s->regs[SONIC_RBWC0] = available & 0xffff;
860 
861     /* Update status */
862     if (dp8393x_rbwc(s) < s->regs[SONIC_EOBC]) {
863         s->regs[SONIC_RCR] |= SONIC_RCR_LPKT;
864     }
865     s->regs[SONIC_RCR] |= packet_type;
866     s->regs[SONIC_RCR] |= SONIC_RCR_PRX;
867     if (s->loopback_packet) {
868         s->regs[SONIC_RCR] |= SONIC_RCR_LBK;
869         s->loopback_packet = 0;
870     }
871 
872     /* Write status to memory */
873     trace_dp8393x_receive_write_status(dp8393x_crda(s));
874     dp8393x_put(s, width, 0, s->regs[SONIC_RCR]); /* status */
875     dp8393x_put(s, width, 1, rx_len); /* byte count */
876     dp8393x_put(s, width, 2, s->regs[SONIC_TRBA0]); /* pkt_ptr0 */
877     dp8393x_put(s, width, 3, s->regs[SONIC_TRBA1]); /* pkt_ptr1 */
878     dp8393x_put(s, width, 4, s->regs[SONIC_RSC]); /* seq_no */
879     size = sizeof(uint16_t) * 5 * width;
880     address_space_write(&s->as, dp8393x_crda(s),
881                         MEMTXATTRS_UNSPECIFIED,
882                         s->data, size);
883 
884     /* Check link field */
885     size = sizeof(uint16_t) * width;
886     address_space_read(&s->as,
887                        dp8393x_crda(s) + sizeof(uint16_t) * 5 * width,
888                        MEMTXATTRS_UNSPECIFIED, s->data, size);
889     s->regs[SONIC_LLFA] = dp8393x_get(s, width, 0);
890     if (s->regs[SONIC_LLFA] & SONIC_DESC_EOL) {
891         /* EOL detected */
892         s->regs[SONIC_ISR] |= SONIC_ISR_RDE;
893     } else {
894         /* Clear in_use */
895         size = sizeof(uint16_t) * width;
896         address = dp8393x_crda(s) + sizeof(uint16_t) * 6 * width;
897         dp8393x_put(s, width, 0, 0);
898         address_space_write(&s->as, address, MEMTXATTRS_UNSPECIFIED,
899                             s->data, size);
900 
901         /* Move to next descriptor */
902         s->regs[SONIC_CRDA] = s->regs[SONIC_LLFA];
903         s->regs[SONIC_ISR] |= SONIC_ISR_PKTRX;
904     }
905 
906     dp8393x_update_irq(s);
907 
908     s->regs[SONIC_RSC] = (s->regs[SONIC_RSC] & 0xff00) |
909                          ((s->regs[SONIC_RSC] + 1) & 0x00ff);
910 
911 done:
912 
913     if (s->regs[SONIC_RCR] & SONIC_RCR_LPKT) {
914         if (s->regs[SONIC_RRP] == s->regs[SONIC_RWP]) {
915             /* Stop packet reception */
916             s->last_rba_is_full = true;
917         } else {
918             /* Read next resource */
919             dp8393x_do_read_rra(s);
920         }
921     }
922 
923     return pkt_size;
924 }
925 
926 static void dp8393x_reset(DeviceState *dev)
927 {
928     dp8393xState *s = DP8393X(dev);
929     timer_del(s->watchdog);
930 
931     memset(s->regs, 0, sizeof(s->regs));
932     s->regs[SONIC_SR] = 0x0004; /* only revision recognized by Linux/mips */
933     s->regs[SONIC_CR] = SONIC_CR_RST | SONIC_CR_STP | SONIC_CR_RXDIS;
934     s->regs[SONIC_DCR] &= ~(SONIC_DCR_EXBUS | SONIC_DCR_LBR);
935     s->regs[SONIC_RCR] &= ~(SONIC_RCR_LB0 | SONIC_RCR_LB1 | SONIC_RCR_BRD |
936                             SONIC_RCR_RNT);
937     s->regs[SONIC_TCR] |= SONIC_TCR_NCRS | SONIC_TCR_PTX;
938     s->regs[SONIC_TCR] &= ~SONIC_TCR_BCM;
939     s->regs[SONIC_IMR] = 0;
940     s->regs[SONIC_ISR] = 0;
941     s->regs[SONIC_DCR2] = 0;
942     s->regs[SONIC_EOBC] = 0x02F8;
943     s->regs[SONIC_RSC] = 0;
944     s->regs[SONIC_CE] = 0;
945     s->regs[SONIC_RSC] = 0;
946 
947     /* Network cable is connected */
948     s->regs[SONIC_RCR] |= SONIC_RCR_CRS;
949 
950     dp8393x_update_irq(s);
951 }
952 
953 static NetClientInfo net_dp83932_info = {
954     .type = NET_CLIENT_DRIVER_NIC,
955     .size = sizeof(NICState),
956     .can_receive = dp8393x_can_receive,
957     .receive = dp8393x_receive,
958 };
959 
960 static void dp8393x_instance_init(Object *obj)
961 {
962     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
963     dp8393xState *s = DP8393X(obj);
964 
965     sysbus_init_mmio(sbd, &s->mmio);
966     sysbus_init_irq(sbd, &s->irq);
967 }
968 
969 static void dp8393x_realize(DeviceState *dev, Error **errp)
970 {
971     dp8393xState *s = DP8393X(dev);
972 
973     address_space_init(&s->as, s->dma_mr, "dp8393x");
974     memory_region_init_io(&s->mmio, OBJECT(dev), &dp8393x_ops, s,
975                           "dp8393x-regs", 0x40 << s->it_shift);
976 
977     s->nic = qemu_new_nic(&net_dp83932_info, &s->conf,
978                           object_get_typename(OBJECT(dev)), dev->id, s);
979     qemu_format_nic_info_str(qemu_get_queue(s->nic), s->conf.macaddr.a);
980 
981     s->watchdog = timer_new_ns(QEMU_CLOCK_VIRTUAL, dp8393x_watchdog, s);
982 }
983 
984 static const VMStateDescription vmstate_dp8393x = {
985     .name = "dp8393x",
986     .version_id = 0,
987     .minimum_version_id = 0,
988     .fields = (VMStateField []) {
989         VMSTATE_BUFFER_UNSAFE(cam, dp8393xState, 0, 16 * 6),
990         VMSTATE_UINT16_ARRAY(regs, dp8393xState, 0x40),
991         VMSTATE_END_OF_LIST()
992     }
993 };
994 
995 static Property dp8393x_properties[] = {
996     DEFINE_NIC_PROPERTIES(dp8393xState, conf),
997     DEFINE_PROP_LINK("dma_mr", dp8393xState, dma_mr,
998                      TYPE_MEMORY_REGION, MemoryRegion *),
999     DEFINE_PROP_UINT8("it_shift", dp8393xState, it_shift, 0),
1000     DEFINE_PROP_BOOL("big_endian", dp8393xState, big_endian, false),
1001     DEFINE_PROP_END_OF_LIST(),
1002 };
1003 
1004 static void dp8393x_class_init(ObjectClass *klass, void *data)
1005 {
1006     DeviceClass *dc = DEVICE_CLASS(klass);
1007 
1008     set_bit(DEVICE_CATEGORY_NETWORK, dc->categories);
1009     dc->realize = dp8393x_realize;
1010     dc->reset = dp8393x_reset;
1011     dc->vmsd = &vmstate_dp8393x;
1012     device_class_set_props(dc, dp8393x_properties);
1013 }
1014 
1015 static const TypeInfo dp8393x_info = {
1016     .name          = TYPE_DP8393X,
1017     .parent        = TYPE_SYS_BUS_DEVICE,
1018     .instance_size = sizeof(dp8393xState),
1019     .instance_init = dp8393x_instance_init,
1020     .class_init    = dp8393x_class_init,
1021 };
1022 
1023 static void dp8393x_register_types(void)
1024 {
1025     type_register_static(&dp8393x_info);
1026 }
1027 
1028 type_init(dp8393x_register_types)
1029