xref: /openbmc/qemu/hw/net/dp8393x.c (revision 8fa3b702)
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 
32 //#define DEBUG_SONIC
33 
34 #define SONIC_PROM_SIZE 0x1000
35 
36 #ifdef DEBUG_SONIC
37 #define DPRINTF(fmt, ...) \
38 do { printf("sonic: " fmt , ##  __VA_ARGS__); } while (0)
39 static const char* reg_names[] = {
40     "CR", "DCR", "RCR", "TCR", "IMR", "ISR", "UTDA", "CTDA",
41     "TPS", "TFC", "TSA0", "TSA1", "TFS", "URDA", "CRDA", "CRBA0",
42     "CRBA1", "RBWC0", "RBWC1", "EOBC", "URRA", "RSA", "REA", "RRP",
43     "RWP", "TRBA0", "TRBA1", "0x1b", "0x1c", "0x1d", "0x1e", "LLFA",
44     "TTDA", "CEP", "CAP2", "CAP1", "CAP0", "CE", "CDP", "CDC",
45     "SR", "WT0", "WT1", "RSC", "CRCT", "FAET", "MPT", "MDT",
46     "0x30", "0x31", "0x32", "0x33", "0x34", "0x35", "0x36", "0x37",
47     "0x38", "0x39", "0x3a", "0x3b", "0x3c", "0x3d", "0x3e", "DCR2" };
48 #else
49 #define DPRINTF(fmt, ...) do {} while (0)
50 #endif
51 
52 #define SONIC_ERROR(fmt, ...) \
53 do { printf("sonic ERROR: %s: " fmt, __func__ , ## __VA_ARGS__); } while (0)
54 
55 #define SONIC_CR     0x00
56 #define SONIC_DCR    0x01
57 #define SONIC_RCR    0x02
58 #define SONIC_TCR    0x03
59 #define SONIC_IMR    0x04
60 #define SONIC_ISR    0x05
61 #define SONIC_UTDA   0x06
62 #define SONIC_CTDA   0x07
63 #define SONIC_TPS    0x08
64 #define SONIC_TFC    0x09
65 #define SONIC_TSA0   0x0a
66 #define SONIC_TSA1   0x0b
67 #define SONIC_TFS    0x0c
68 #define SONIC_URDA   0x0d
69 #define SONIC_CRDA   0x0e
70 #define SONIC_CRBA0  0x0f
71 #define SONIC_CRBA1  0x10
72 #define SONIC_RBWC0  0x11
73 #define SONIC_RBWC1  0x12
74 #define SONIC_EOBC   0x13
75 #define SONIC_URRA   0x14
76 #define SONIC_RSA    0x15
77 #define SONIC_REA    0x16
78 #define SONIC_RRP    0x17
79 #define SONIC_RWP    0x18
80 #define SONIC_TRBA0  0x19
81 #define SONIC_TRBA1  0x1a
82 #define SONIC_LLFA   0x1f
83 #define SONIC_TTDA   0x20
84 #define SONIC_CEP    0x21
85 #define SONIC_CAP2   0x22
86 #define SONIC_CAP1   0x23
87 #define SONIC_CAP0   0x24
88 #define SONIC_CE     0x25
89 #define SONIC_CDP    0x26
90 #define SONIC_CDC    0x27
91 #define SONIC_SR     0x28
92 #define SONIC_WT0    0x29
93 #define SONIC_WT1    0x2a
94 #define SONIC_RSC    0x2b
95 #define SONIC_CRCT   0x2c
96 #define SONIC_FAET   0x2d
97 #define SONIC_MPT    0x2e
98 #define SONIC_MDT    0x2f
99 #define SONIC_DCR2   0x3f
100 
101 #define SONIC_CR_HTX     0x0001
102 #define SONIC_CR_TXP     0x0002
103 #define SONIC_CR_RXDIS   0x0004
104 #define SONIC_CR_RXEN    0x0008
105 #define SONIC_CR_STP     0x0010
106 #define SONIC_CR_ST      0x0020
107 #define SONIC_CR_RST     0x0080
108 #define SONIC_CR_RRRA    0x0100
109 #define SONIC_CR_LCAM    0x0200
110 #define SONIC_CR_MASK    0x03bf
111 
112 #define SONIC_DCR_DW     0x0020
113 #define SONIC_DCR_LBR    0x2000
114 #define SONIC_DCR_EXBUS  0x8000
115 
116 #define SONIC_RCR_PRX    0x0001
117 #define SONIC_RCR_LBK    0x0002
118 #define SONIC_RCR_FAER   0x0004
119 #define SONIC_RCR_CRCR   0x0008
120 #define SONIC_RCR_CRS    0x0020
121 #define SONIC_RCR_LPKT   0x0040
122 #define SONIC_RCR_BC     0x0080
123 #define SONIC_RCR_MC     0x0100
124 #define SONIC_RCR_LB0    0x0200
125 #define SONIC_RCR_LB1    0x0400
126 #define SONIC_RCR_AMC    0x0800
127 #define SONIC_RCR_PRO    0x1000
128 #define SONIC_RCR_BRD    0x2000
129 #define SONIC_RCR_RNT    0x4000
130 
131 #define SONIC_TCR_PTX    0x0001
132 #define SONIC_TCR_BCM    0x0002
133 #define SONIC_TCR_FU     0x0004
134 #define SONIC_TCR_EXC    0x0040
135 #define SONIC_TCR_CRSL   0x0080
136 #define SONIC_TCR_NCRS   0x0100
137 #define SONIC_TCR_EXD    0x0400
138 #define SONIC_TCR_CRCI   0x2000
139 #define SONIC_TCR_PINT   0x8000
140 
141 #define SONIC_ISR_RBAE   0x0010
142 #define SONIC_ISR_RBE    0x0020
143 #define SONIC_ISR_RDE    0x0040
144 #define SONIC_ISR_TC     0x0080
145 #define SONIC_ISR_TXDN   0x0200
146 #define SONIC_ISR_PKTRX  0x0400
147 #define SONIC_ISR_PINT   0x0800
148 #define SONIC_ISR_LCD    0x1000
149 
150 #define SONIC_DESC_EOL   0x0001
151 #define SONIC_DESC_ADDR  0xFFFE
152 
153 #define TYPE_DP8393X "dp8393x"
154 typedef struct dp8393xState dp8393xState;
155 DECLARE_INSTANCE_CHECKER(dp8393xState, DP8393X,
156                          TYPE_DP8393X)
157 
158 struct dp8393xState {
159     SysBusDevice parent_obj;
160 
161     /* Hardware */
162     uint8_t it_shift;
163     bool big_endian;
164     bool last_rba_is_full;
165     qemu_irq irq;
166 #ifdef DEBUG_SONIC
167     int irq_level;
168 #endif
169     QEMUTimer *watchdog;
170     int64_t wt_last_update;
171     NICConf conf;
172     NICState *nic;
173     MemoryRegion mmio;
174     MemoryRegion prom;
175 
176     /* Registers */
177     uint8_t cam[16][6];
178     uint16_t regs[0x40];
179 
180     /* Temporaries */
181     uint8_t tx_buffer[0x10000];
182     uint16_t data[12];
183     int loopback_packet;
184 
185     /* Memory access */
186     MemoryRegion *dma_mr;
187     AddressSpace as;
188 };
189 
190 /* Accessor functions for values which are formed by
191  * concatenating two 16 bit device registers. By putting these
192  * in their own functions with a uint32_t return type we avoid the
193  * pitfall of implicit sign extension where ((x << 16) | y) is a
194  * signed 32 bit integer that might get sign-extended to a 64 bit integer.
195  */
196 static uint32_t dp8393x_cdp(dp8393xState *s)
197 {
198     return (s->regs[SONIC_URRA] << 16) | s->regs[SONIC_CDP];
199 }
200 
201 static uint32_t dp8393x_crba(dp8393xState *s)
202 {
203     return (s->regs[SONIC_CRBA1] << 16) | s->regs[SONIC_CRBA0];
204 }
205 
206 static uint32_t dp8393x_crda(dp8393xState *s)
207 {
208     return (s->regs[SONIC_URDA] << 16) |
209            (s->regs[SONIC_CRDA] & SONIC_DESC_ADDR);
210 }
211 
212 static uint32_t dp8393x_rbwc(dp8393xState *s)
213 {
214     return (s->regs[SONIC_RBWC1] << 16) | s->regs[SONIC_RBWC0];
215 }
216 
217 static uint32_t dp8393x_rrp(dp8393xState *s)
218 {
219     return (s->regs[SONIC_URRA] << 16) | s->regs[SONIC_RRP];
220 }
221 
222 static uint32_t dp8393x_tsa(dp8393xState *s)
223 {
224     return (s->regs[SONIC_TSA1] << 16) | s->regs[SONIC_TSA0];
225 }
226 
227 static uint32_t dp8393x_ttda(dp8393xState *s)
228 {
229     return (s->regs[SONIC_UTDA] << 16) |
230            (s->regs[SONIC_TTDA] & SONIC_DESC_ADDR);
231 }
232 
233 static uint32_t dp8393x_wt(dp8393xState *s)
234 {
235     return s->regs[SONIC_WT1] << 16 | s->regs[SONIC_WT0];
236 }
237 
238 static uint16_t dp8393x_get(dp8393xState *s, int width, int offset)
239 {
240     uint16_t val;
241 
242     if (s->big_endian) {
243         val = be16_to_cpu(s->data[offset * width + width - 1]);
244     } else {
245         val = le16_to_cpu(s->data[offset * width]);
246     }
247     return val;
248 }
249 
250 static void dp8393x_put(dp8393xState *s, int width, int offset,
251                         uint16_t val)
252 {
253     if (s->big_endian) {
254         if (width == 2) {
255             s->data[offset * 2] = 0;
256             s->data[offset * 2 + 1] = cpu_to_be16(val);
257         } else {
258             s->data[offset] = cpu_to_be16(val);
259         }
260     } else {
261         if (width == 2) {
262             s->data[offset * 2] = cpu_to_le16(val);
263             s->data[offset * 2 + 1] = 0;
264         } else {
265             s->data[offset] = cpu_to_le16(val);
266         }
267     }
268 }
269 
270 static void dp8393x_update_irq(dp8393xState *s)
271 {
272     int level = (s->regs[SONIC_IMR] & s->regs[SONIC_ISR]) ? 1 : 0;
273 
274 #ifdef DEBUG_SONIC
275     if (level != s->irq_level) {
276         s->irq_level = level;
277         if (level) {
278             DPRINTF("raise irq, isr is 0x%04x\n", s->regs[SONIC_ISR]);
279         } else {
280             DPRINTF("lower irq\n");
281         }
282     }
283 #endif
284 
285     qemu_set_irq(s->irq, level);
286 }
287 
288 static void dp8393x_do_load_cam(dp8393xState *s)
289 {
290     int width, size;
291     uint16_t index = 0;
292 
293     width = (s->regs[SONIC_DCR] & SONIC_DCR_DW) ? 2 : 1;
294     size = sizeof(uint16_t) * 4 * width;
295 
296     while (s->regs[SONIC_CDC] & 0x1f) {
297         /* Fill current entry */
298         address_space_read(&s->as, dp8393x_cdp(s),
299                            MEMTXATTRS_UNSPECIFIED, s->data, size);
300         s->cam[index][0] = dp8393x_get(s, width, 1) & 0xff;
301         s->cam[index][1] = dp8393x_get(s, width, 1) >> 8;
302         s->cam[index][2] = dp8393x_get(s, width, 2) & 0xff;
303         s->cam[index][3] = dp8393x_get(s, width, 2) >> 8;
304         s->cam[index][4] = dp8393x_get(s, width, 3) & 0xff;
305         s->cam[index][5] = dp8393x_get(s, width, 3) >> 8;
306         DPRINTF("load cam[%d] with %02x%02x%02x%02x%02x%02x\n", index,
307             s->cam[index][0], s->cam[index][1], s->cam[index][2],
308             s->cam[index][3], s->cam[index][4], s->cam[index][5]);
309         /* Move to next entry */
310         s->regs[SONIC_CDC]--;
311         s->regs[SONIC_CDP] += size;
312         index++;
313     }
314 
315     /* Read CAM enable */
316     address_space_read(&s->as, dp8393x_cdp(s),
317                        MEMTXATTRS_UNSPECIFIED, s->data, size);
318     s->regs[SONIC_CE] = dp8393x_get(s, width, 0);
319     DPRINTF("load cam done. cam enable mask 0x%04x\n", s->regs[SONIC_CE]);
320 
321     /* Done */
322     s->regs[SONIC_CR] &= ~SONIC_CR_LCAM;
323     s->regs[SONIC_ISR] |= SONIC_ISR_LCD;
324     dp8393x_update_irq(s);
325 }
326 
327 static void dp8393x_do_read_rra(dp8393xState *s)
328 {
329     int width, size;
330 
331     /* Read memory */
332     width = (s->regs[SONIC_DCR] & SONIC_DCR_DW) ? 2 : 1;
333     size = sizeof(uint16_t) * 4 * width;
334     address_space_read(&s->as, dp8393x_rrp(s),
335                        MEMTXATTRS_UNSPECIFIED, s->data, size);
336 
337     /* Update SONIC registers */
338     s->regs[SONIC_CRBA0] = dp8393x_get(s, width, 0);
339     s->regs[SONIC_CRBA1] = dp8393x_get(s, width, 1);
340     s->regs[SONIC_RBWC0] = dp8393x_get(s, width, 2);
341     s->regs[SONIC_RBWC1] = dp8393x_get(s, width, 3);
342     DPRINTF("CRBA0/1: 0x%04x/0x%04x, RBWC0/1: 0x%04x/0x%04x\n",
343         s->regs[SONIC_CRBA0], s->regs[SONIC_CRBA1],
344         s->regs[SONIC_RBWC0], s->regs[SONIC_RBWC1]);
345 
346     /* Go to next entry */
347     s->regs[SONIC_RRP] += size;
348 
349     /* Handle wrap */
350     if (s->regs[SONIC_RRP] == s->regs[SONIC_REA]) {
351         s->regs[SONIC_RRP] = s->regs[SONIC_RSA];
352     }
353 
354     /* Warn the host if CRBA now has the last available resource */
355     if (s->regs[SONIC_RRP] == s->regs[SONIC_RWP])
356     {
357         s->regs[SONIC_ISR] |= SONIC_ISR_RBE;
358         dp8393x_update_irq(s);
359     }
360 
361     /* Allow packet reception */
362     s->last_rba_is_full = false;
363 }
364 
365 static void dp8393x_do_software_reset(dp8393xState *s)
366 {
367     timer_del(s->watchdog);
368 
369     s->regs[SONIC_CR] &= ~(SONIC_CR_LCAM | SONIC_CR_RRRA | SONIC_CR_TXP | SONIC_CR_HTX);
370     s->regs[SONIC_CR] |= SONIC_CR_RST | SONIC_CR_RXDIS;
371 }
372 
373 static void dp8393x_set_next_tick(dp8393xState *s)
374 {
375     uint32_t ticks;
376     int64_t delay;
377 
378     if (s->regs[SONIC_CR] & SONIC_CR_STP) {
379         timer_del(s->watchdog);
380         return;
381     }
382 
383     ticks = dp8393x_wt(s);
384     s->wt_last_update = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
385     delay = NANOSECONDS_PER_SECOND * ticks / 5000000;
386     timer_mod(s->watchdog, s->wt_last_update + delay);
387 }
388 
389 static void dp8393x_update_wt_regs(dp8393xState *s)
390 {
391     int64_t elapsed;
392     uint32_t val;
393 
394     if (s->regs[SONIC_CR] & SONIC_CR_STP) {
395         timer_del(s->watchdog);
396         return;
397     }
398 
399     elapsed = s->wt_last_update - qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
400     val = dp8393x_wt(s);
401     val -= elapsed / 5000000;
402     s->regs[SONIC_WT1] = (val >> 16) & 0xffff;
403     s->regs[SONIC_WT0] = (val >> 0)  & 0xffff;
404     dp8393x_set_next_tick(s);
405 
406 }
407 
408 static void dp8393x_do_start_timer(dp8393xState *s)
409 {
410     s->regs[SONIC_CR] &= ~SONIC_CR_STP;
411     dp8393x_set_next_tick(s);
412 }
413 
414 static void dp8393x_do_stop_timer(dp8393xState *s)
415 {
416     s->regs[SONIC_CR] &= ~SONIC_CR_ST;
417     dp8393x_update_wt_regs(s);
418 }
419 
420 static bool dp8393x_can_receive(NetClientState *nc);
421 
422 static void dp8393x_do_receiver_enable(dp8393xState *s)
423 {
424     s->regs[SONIC_CR] &= ~SONIC_CR_RXDIS;
425     if (dp8393x_can_receive(s->nic->ncs)) {
426         qemu_flush_queued_packets(qemu_get_queue(s->nic));
427     }
428 }
429 
430 static void dp8393x_do_receiver_disable(dp8393xState *s)
431 {
432     s->regs[SONIC_CR] &= ~SONIC_CR_RXEN;
433 }
434 
435 static void dp8393x_do_transmit_packets(dp8393xState *s)
436 {
437     NetClientState *nc = qemu_get_queue(s->nic);
438     int width, size;
439     int tx_len, len;
440     uint16_t i;
441 
442     width = (s->regs[SONIC_DCR] & SONIC_DCR_DW) ? 2 : 1;
443 
444     while (1) {
445         /* Read memory */
446         size = sizeof(uint16_t) * 6 * width;
447         s->regs[SONIC_TTDA] = s->regs[SONIC_CTDA];
448         DPRINTF("Transmit packet at %08x\n", dp8393x_ttda(s));
449         address_space_read(&s->as, dp8393x_ttda(s) + sizeof(uint16_t) * width,
450                            MEMTXATTRS_UNSPECIFIED, s->data, size);
451         tx_len = 0;
452 
453         /* Update registers */
454         s->regs[SONIC_TCR] = dp8393x_get(s, width, 0) & 0xf000;
455         s->regs[SONIC_TPS] = dp8393x_get(s, width, 1);
456         s->regs[SONIC_TFC] = dp8393x_get(s, width, 2);
457         s->regs[SONIC_TSA0] = dp8393x_get(s, width, 3);
458         s->regs[SONIC_TSA1] = dp8393x_get(s, width, 4);
459         s->regs[SONIC_TFS] = dp8393x_get(s, width, 5);
460 
461         /* Handle programmable interrupt */
462         if (s->regs[SONIC_TCR] & SONIC_TCR_PINT) {
463             s->regs[SONIC_ISR] |= SONIC_ISR_PINT;
464         } else {
465             s->regs[SONIC_ISR] &= ~SONIC_ISR_PINT;
466         }
467 
468         for (i = 0; i < s->regs[SONIC_TFC]; ) {
469             /* Append fragment */
470             len = s->regs[SONIC_TFS];
471             if (tx_len + len > sizeof(s->tx_buffer)) {
472                 len = sizeof(s->tx_buffer) - tx_len;
473             }
474             address_space_read(&s->as, dp8393x_tsa(s), MEMTXATTRS_UNSPECIFIED,
475                                &s->tx_buffer[tx_len], len);
476             tx_len += len;
477 
478             i++;
479             if (i != s->regs[SONIC_TFC]) {
480                 /* Read next fragment details */
481                 size = sizeof(uint16_t) * 3 * width;
482                 address_space_read(&s->as,
483                                    dp8393x_ttda(s)
484                                    + sizeof(uint16_t) * width * (4 + 3 * i),
485                                    MEMTXATTRS_UNSPECIFIED, s->data,
486                                    size);
487                 s->regs[SONIC_TSA0] = dp8393x_get(s, width, 0);
488                 s->regs[SONIC_TSA1] = dp8393x_get(s, width, 1);
489                 s->regs[SONIC_TFS] = dp8393x_get(s, width, 2);
490             }
491         }
492 
493         /* Handle Ethernet checksum */
494         if (!(s->regs[SONIC_TCR] & SONIC_TCR_CRCI)) {
495             /* Don't append FCS there, to look like slirp packets
496              * which don't have one */
497         } else {
498             /* Remove existing FCS */
499             tx_len -= 4;
500         }
501 
502         if (s->regs[SONIC_RCR] & (SONIC_RCR_LB1 | SONIC_RCR_LB0)) {
503             /* Loopback */
504             s->regs[SONIC_TCR] |= SONIC_TCR_CRSL;
505             if (nc->info->can_receive(nc)) {
506                 s->loopback_packet = 1;
507                 nc->info->receive(nc, s->tx_buffer, tx_len);
508             }
509         } else {
510             /* Transmit packet */
511             qemu_send_packet(nc, s->tx_buffer, tx_len);
512         }
513         s->regs[SONIC_TCR] |= SONIC_TCR_PTX;
514 
515         /* Write status */
516         dp8393x_put(s, width, 0,
517                     s->regs[SONIC_TCR] & 0x0fff); /* status */
518         size = sizeof(uint16_t) * width;
519         address_space_write(&s->as, dp8393x_ttda(s),
520                             MEMTXATTRS_UNSPECIFIED, s->data, size);
521 
522         if (!(s->regs[SONIC_CR] & SONIC_CR_HTX)) {
523             /* Read footer of packet */
524             size = sizeof(uint16_t) * width;
525             address_space_read(&s->as,
526                                dp8393x_ttda(s)
527                                + sizeof(uint16_t) * width
528                                  * (4 + 3 * s->regs[SONIC_TFC]),
529                                MEMTXATTRS_UNSPECIFIED, s->data,
530                                size);
531             s->regs[SONIC_CTDA] = dp8393x_get(s, width, 0);
532             if (s->regs[SONIC_CTDA] & SONIC_DESC_EOL) {
533                 /* EOL detected */
534                 break;
535             }
536         }
537     }
538 
539     /* Done */
540     s->regs[SONIC_CR] &= ~SONIC_CR_TXP;
541     s->regs[SONIC_ISR] |= SONIC_ISR_TXDN;
542     dp8393x_update_irq(s);
543 }
544 
545 static void dp8393x_do_halt_transmission(dp8393xState *s)
546 {
547     /* Nothing to do */
548 }
549 
550 static void dp8393x_do_command(dp8393xState *s, uint16_t command)
551 {
552     if ((s->regs[SONIC_CR] & SONIC_CR_RST) && !(command & SONIC_CR_RST)) {
553         s->regs[SONIC_CR] &= ~SONIC_CR_RST;
554         return;
555     }
556 
557     s->regs[SONIC_CR] |= (command & SONIC_CR_MASK);
558 
559     if (command & SONIC_CR_HTX)
560         dp8393x_do_halt_transmission(s);
561     if (command & SONIC_CR_TXP)
562         dp8393x_do_transmit_packets(s);
563     if (command & SONIC_CR_RXDIS)
564         dp8393x_do_receiver_disable(s);
565     if (command & SONIC_CR_RXEN)
566         dp8393x_do_receiver_enable(s);
567     if (command & SONIC_CR_STP)
568         dp8393x_do_stop_timer(s);
569     if (command & SONIC_CR_ST)
570         dp8393x_do_start_timer(s);
571     if (command & SONIC_CR_RST)
572         dp8393x_do_software_reset(s);
573     if (command & SONIC_CR_RRRA) {
574         dp8393x_do_read_rra(s);
575         s->regs[SONIC_CR] &= ~SONIC_CR_RRRA;
576     }
577     if (command & SONIC_CR_LCAM)
578         dp8393x_do_load_cam(s);
579 }
580 
581 static uint64_t dp8393x_read(void *opaque, hwaddr addr, unsigned int size)
582 {
583     dp8393xState *s = opaque;
584     int reg = addr >> s->it_shift;
585     uint16_t val = 0;
586 
587     switch (reg) {
588         /* Update data before reading it */
589         case SONIC_WT0:
590         case SONIC_WT1:
591             dp8393x_update_wt_regs(s);
592             val = s->regs[reg];
593             break;
594         /* Accept read to some registers only when in reset mode */
595         case SONIC_CAP2:
596         case SONIC_CAP1:
597         case SONIC_CAP0:
598             if (s->regs[SONIC_CR] & SONIC_CR_RST) {
599                 val = s->cam[s->regs[SONIC_CEP] & 0xf][2* (SONIC_CAP0 - reg) + 1] << 8;
600                 val |= s->cam[s->regs[SONIC_CEP] & 0xf][2* (SONIC_CAP0 - reg)];
601             }
602             break;
603         /* All other registers have no special contrainst */
604         default:
605             val = s->regs[reg];
606     }
607 
608     DPRINTF("read 0x%04x from reg %s\n", val, reg_names[reg]);
609 
610     return s->big_endian ? val << 16 : val;
611 }
612 
613 static void dp8393x_write(void *opaque, hwaddr addr, uint64_t data,
614                           unsigned int size)
615 {
616     dp8393xState *s = opaque;
617     int reg = addr >> s->it_shift;
618     uint32_t val = s->big_endian ? data >> 16 : data;
619 
620     DPRINTF("write 0x%04x to reg %s\n", (uint16_t)val, reg_names[reg]);
621 
622     switch (reg) {
623         /* Command register */
624         case SONIC_CR:
625             dp8393x_do_command(s, val);
626             break;
627         /* Prevent write to read-only registers */
628         case SONIC_CAP2:
629         case SONIC_CAP1:
630         case SONIC_CAP0:
631         case SONIC_SR:
632         case SONIC_MDT:
633             DPRINTF("writing to reg %d invalid\n", reg);
634             break;
635         /* Accept write to some registers only when in reset mode */
636         case SONIC_DCR:
637             if (s->regs[SONIC_CR] & SONIC_CR_RST) {
638                 s->regs[reg] = val & 0xbfff;
639             } else {
640                 DPRINTF("writing to DCR invalid\n");
641             }
642             break;
643         case SONIC_DCR2:
644             if (s->regs[SONIC_CR] & SONIC_CR_RST) {
645                 s->regs[reg] = val & 0xf017;
646             } else {
647                 DPRINTF("writing to DCR2 invalid\n");
648             }
649             break;
650         /* 12 lower bytes are Read Only */
651         case SONIC_TCR:
652             s->regs[reg] = val & 0xf000;
653             break;
654         /* 9 lower bytes are Read Only */
655         case SONIC_RCR:
656             s->regs[reg] = val & 0xffe0;
657             break;
658         /* Ignore most significant bit */
659         case SONIC_IMR:
660             s->regs[reg] = val & 0x7fff;
661             dp8393x_update_irq(s);
662             break;
663         /* Clear bits by writing 1 to them */
664         case SONIC_ISR:
665             val &= s->regs[reg];
666             s->regs[reg] &= ~val;
667             if (val & SONIC_ISR_RBE) {
668                 dp8393x_do_read_rra(s);
669             }
670             dp8393x_update_irq(s);
671             break;
672         /* The guest is required to store aligned pointers here */
673         case SONIC_RSA:
674         case SONIC_REA:
675         case SONIC_RRP:
676         case SONIC_RWP:
677             if (s->regs[SONIC_DCR] & SONIC_DCR_DW) {
678                 s->regs[reg] = val & 0xfffc;
679             } else {
680                 s->regs[reg] = val & 0xfffe;
681             }
682             break;
683         /* Invert written value for some registers */
684         case SONIC_CRCT:
685         case SONIC_FAET:
686         case SONIC_MPT:
687             s->regs[reg] = val ^ 0xffff;
688             break;
689         /* All other registers have no special contrainst */
690         default:
691             s->regs[reg] = val;
692     }
693 
694     if (reg == SONIC_WT0 || reg == SONIC_WT1) {
695         dp8393x_set_next_tick(s);
696     }
697 }
698 
699 static const MemoryRegionOps dp8393x_ops = {
700     .read = dp8393x_read,
701     .write = dp8393x_write,
702     .impl.min_access_size = 4,
703     .impl.max_access_size = 4,
704     .endianness = DEVICE_NATIVE_ENDIAN,
705 };
706 
707 static void dp8393x_watchdog(void *opaque)
708 {
709     dp8393xState *s = opaque;
710 
711     if (s->regs[SONIC_CR] & SONIC_CR_STP) {
712         return;
713     }
714 
715     s->regs[SONIC_WT1] = 0xffff;
716     s->regs[SONIC_WT0] = 0xffff;
717     dp8393x_set_next_tick(s);
718 
719     /* Signal underflow */
720     s->regs[SONIC_ISR] |= SONIC_ISR_TC;
721     dp8393x_update_irq(s);
722 }
723 
724 static bool dp8393x_can_receive(NetClientState *nc)
725 {
726     dp8393xState *s = qemu_get_nic_opaque(nc);
727 
728     return !!(s->regs[SONIC_CR] & SONIC_CR_RXEN);
729 }
730 
731 static int dp8393x_receive_filter(dp8393xState *s, const uint8_t * buf,
732                                   int size)
733 {
734     static const uint8_t bcast[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
735     int i;
736 
737     /* Check promiscuous mode */
738     if ((s->regs[SONIC_RCR] & SONIC_RCR_PRO) && (buf[0] & 1) == 0) {
739         return 0;
740     }
741 
742     /* Check multicast packets */
743     if ((s->regs[SONIC_RCR] & SONIC_RCR_AMC) && (buf[0] & 1) == 1) {
744         return SONIC_RCR_MC;
745     }
746 
747     /* Check broadcast */
748     if ((s->regs[SONIC_RCR] & SONIC_RCR_BRD) && !memcmp(buf, bcast, sizeof(bcast))) {
749         return SONIC_RCR_BC;
750     }
751 
752     /* Check CAM */
753     for (i = 0; i < 16; i++) {
754         if (s->regs[SONIC_CE] & (1 << i)) {
755              /* Entry enabled */
756              if (!memcmp(buf, s->cam[i], sizeof(s->cam[i]))) {
757                  return 0;
758              }
759         }
760     }
761 
762     return -1;
763 }
764 
765 static ssize_t dp8393x_receive(NetClientState *nc, const uint8_t * buf,
766                                size_t pkt_size)
767 {
768     dp8393xState *s = qemu_get_nic_opaque(nc);
769     int packet_type;
770     uint32_t available, address;
771     int width, rx_len, padded_len;
772     uint32_t checksum;
773     int size;
774 
775     s->regs[SONIC_RCR] &= ~(SONIC_RCR_PRX | SONIC_RCR_LBK | SONIC_RCR_FAER |
776         SONIC_RCR_CRCR | SONIC_RCR_LPKT | SONIC_RCR_BC | SONIC_RCR_MC);
777 
778     if (s->last_rba_is_full) {
779         return pkt_size;
780     }
781 
782     rx_len = pkt_size + sizeof(checksum);
783     if (s->regs[SONIC_DCR] & SONIC_DCR_DW) {
784         width = 2;
785         padded_len = ((rx_len - 1) | 3) + 1;
786     } else {
787         width = 1;
788         padded_len = ((rx_len - 1) | 1) + 1;
789     }
790 
791     if (padded_len > dp8393x_rbwc(s) * 2) {
792         DPRINTF("oversize packet, pkt_size is %d\n", pkt_size);
793         s->regs[SONIC_ISR] |= SONIC_ISR_RBAE;
794         dp8393x_update_irq(s);
795         s->regs[SONIC_RCR] |= SONIC_RCR_LPKT;
796         goto done;
797     }
798 
799     packet_type = dp8393x_receive_filter(s, buf, pkt_size);
800     if (packet_type < 0) {
801         DPRINTF("packet not for netcard\n");
802         return -1;
803     }
804 
805     /* Check for EOL */
806     if (s->regs[SONIC_LLFA] & SONIC_DESC_EOL) {
807         /* Are we still in resource exhaustion? */
808         size = sizeof(uint16_t) * 1 * width;
809         address = dp8393x_crda(s) + sizeof(uint16_t) * 5 * width;
810         address_space_read(&s->as, address, MEMTXATTRS_UNSPECIFIED,
811                            s->data, size);
812         s->regs[SONIC_LLFA] = dp8393x_get(s, width, 0);
813         if (s->regs[SONIC_LLFA] & SONIC_DESC_EOL) {
814             /* Still EOL ; stop reception */
815             return -1;
816         }
817         /* Link has been updated by host */
818 
819         /* Clear in_use */
820         size = sizeof(uint16_t) * width;
821         address = dp8393x_crda(s) + sizeof(uint16_t) * 6 * width;
822         dp8393x_put(s, width, 0, 0);
823         address_space_rw(&s->as, address, MEMTXATTRS_UNSPECIFIED,
824                          (uint8_t *)s->data, size, 1);
825 
826         /* Move to next descriptor */
827         s->regs[SONIC_CRDA] = s->regs[SONIC_LLFA];
828         s->regs[SONIC_ISR] |= SONIC_ISR_PKTRX;
829     }
830 
831     /* Save current position */
832     s->regs[SONIC_TRBA1] = s->regs[SONIC_CRBA1];
833     s->regs[SONIC_TRBA0] = s->regs[SONIC_CRBA0];
834 
835     /* Calculate the ethernet checksum */
836     checksum = cpu_to_le32(crc32(0, buf, pkt_size));
837 
838     /* Put packet into RBA */
839     DPRINTF("Receive packet at %08x\n", dp8393x_crba(s));
840     address = dp8393x_crba(s);
841     address_space_write(&s->as, address, MEMTXATTRS_UNSPECIFIED,
842                         buf, pkt_size);
843     address += pkt_size;
844 
845     /* Put frame checksum into RBA */
846     address_space_write(&s->as, address, MEMTXATTRS_UNSPECIFIED,
847                         &checksum, sizeof(checksum));
848     address += sizeof(checksum);
849 
850     /* Pad short packets to keep pointers aligned */
851     if (rx_len < padded_len) {
852         size = padded_len - rx_len;
853         address_space_rw(&s->as, address, MEMTXATTRS_UNSPECIFIED,
854             (uint8_t *)"\xFF\xFF\xFF", size, 1);
855         address += size;
856     }
857 
858     s->regs[SONIC_CRBA1] = address >> 16;
859     s->regs[SONIC_CRBA0] = address & 0xffff;
860     available = dp8393x_rbwc(s);
861     available -= padded_len >> 1;
862     s->regs[SONIC_RBWC1] = available >> 16;
863     s->regs[SONIC_RBWC0] = available & 0xffff;
864 
865     /* Update status */
866     if (dp8393x_rbwc(s) < s->regs[SONIC_EOBC]) {
867         s->regs[SONIC_RCR] |= SONIC_RCR_LPKT;
868     }
869     s->regs[SONIC_RCR] |= packet_type;
870     s->regs[SONIC_RCR] |= SONIC_RCR_PRX;
871     if (s->loopback_packet) {
872         s->regs[SONIC_RCR] |= SONIC_RCR_LBK;
873         s->loopback_packet = 0;
874     }
875 
876     /* Write status to memory */
877     DPRINTF("Write status at %08x\n", dp8393x_crda(s));
878     dp8393x_put(s, width, 0, s->regs[SONIC_RCR]); /* status */
879     dp8393x_put(s, width, 1, rx_len); /* byte count */
880     dp8393x_put(s, width, 2, s->regs[SONIC_TRBA0]); /* pkt_ptr0 */
881     dp8393x_put(s, width, 3, s->regs[SONIC_TRBA1]); /* pkt_ptr1 */
882     dp8393x_put(s, width, 4, s->regs[SONIC_RSC]); /* seq_no */
883     size = sizeof(uint16_t) * 5 * width;
884     address_space_write(&s->as, dp8393x_crda(s),
885                         MEMTXATTRS_UNSPECIFIED,
886                         s->data, size);
887 
888     /* Check link field */
889     size = sizeof(uint16_t) * width;
890     address_space_read(&s->as,
891                        dp8393x_crda(s) + sizeof(uint16_t) * 5 * width,
892                        MEMTXATTRS_UNSPECIFIED, s->data, size);
893     s->regs[SONIC_LLFA] = dp8393x_get(s, width, 0);
894     if (s->regs[SONIC_LLFA] & SONIC_DESC_EOL) {
895         /* EOL detected */
896         s->regs[SONIC_ISR] |= SONIC_ISR_RDE;
897     } else {
898         /* Clear in_use */
899         size = sizeof(uint16_t) * width;
900         address = dp8393x_crda(s) + sizeof(uint16_t) * 6 * width;
901         dp8393x_put(s, width, 0, 0);
902         address_space_write(&s->as, address, MEMTXATTRS_UNSPECIFIED,
903                             s->data, size);
904 
905         /* Move to next descriptor */
906         s->regs[SONIC_CRDA] = s->regs[SONIC_LLFA];
907         s->regs[SONIC_ISR] |= SONIC_ISR_PKTRX;
908     }
909 
910     dp8393x_update_irq(s);
911 
912     s->regs[SONIC_RSC] = (s->regs[SONIC_RSC] & 0xff00) |
913                          ((s->regs[SONIC_RSC] + 1) & 0x00ff);
914 
915 done:
916 
917     if (s->regs[SONIC_RCR] & SONIC_RCR_LPKT) {
918         if (s->regs[SONIC_RRP] == s->regs[SONIC_RWP]) {
919             /* Stop packet reception */
920             s->last_rba_is_full = true;
921         } else {
922             /* Read next resource */
923             dp8393x_do_read_rra(s);
924         }
925     }
926 
927     return pkt_size;
928 }
929 
930 static void dp8393x_reset(DeviceState *dev)
931 {
932     dp8393xState *s = DP8393X(dev);
933     timer_del(s->watchdog);
934 
935     memset(s->regs, 0, sizeof(s->regs));
936     s->regs[SONIC_SR] = 0x0004; /* only revision recognized by Linux/mips */
937     s->regs[SONIC_CR] = SONIC_CR_RST | SONIC_CR_STP | SONIC_CR_RXDIS;
938     s->regs[SONIC_DCR] &= ~(SONIC_DCR_EXBUS | SONIC_DCR_LBR);
939     s->regs[SONIC_RCR] &= ~(SONIC_RCR_LB0 | SONIC_RCR_LB1 | SONIC_RCR_BRD | SONIC_RCR_RNT);
940     s->regs[SONIC_TCR] |= SONIC_TCR_NCRS | SONIC_TCR_PTX;
941     s->regs[SONIC_TCR] &= ~SONIC_TCR_BCM;
942     s->regs[SONIC_IMR] = 0;
943     s->regs[SONIC_ISR] = 0;
944     s->regs[SONIC_DCR2] = 0;
945     s->regs[SONIC_EOBC] = 0x02F8;
946     s->regs[SONIC_RSC] = 0;
947     s->regs[SONIC_CE] = 0;
948     s->regs[SONIC_RSC] = 0;
949 
950     /* Network cable is connected */
951     s->regs[SONIC_RCR] |= SONIC_RCR_CRS;
952 
953     dp8393x_update_irq(s);
954 }
955 
956 static NetClientInfo net_dp83932_info = {
957     .type = NET_CLIENT_DRIVER_NIC,
958     .size = sizeof(NICState),
959     .can_receive = dp8393x_can_receive,
960     .receive = dp8393x_receive,
961 };
962 
963 static void dp8393x_instance_init(Object *obj)
964 {
965     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
966     dp8393xState *s = DP8393X(obj);
967 
968     sysbus_init_mmio(sbd, &s->mmio);
969     sysbus_init_mmio(sbd, &s->prom);
970     sysbus_init_irq(sbd, &s->irq);
971 }
972 
973 static void dp8393x_realize(DeviceState *dev, Error **errp)
974 {
975     dp8393xState *s = DP8393X(dev);
976     int i, checksum;
977     uint8_t *prom;
978     Error *local_err = NULL;
979 
980     address_space_init(&s->as, s->dma_mr, "dp8393x");
981     memory_region_init_io(&s->mmio, OBJECT(dev), &dp8393x_ops, s,
982                           "dp8393x-regs", 0x40 << s->it_shift);
983 
984     s->nic = qemu_new_nic(&net_dp83932_info, &s->conf,
985                           object_get_typename(OBJECT(dev)), dev->id, s);
986     qemu_format_nic_info_str(qemu_get_queue(s->nic), s->conf.macaddr.a);
987 
988     s->watchdog = timer_new_ns(QEMU_CLOCK_VIRTUAL, dp8393x_watchdog, s);
989 
990     memory_region_init_rom(&s->prom, OBJECT(dev), "dp8393x-prom",
991                            SONIC_PROM_SIZE, &local_err);
992     if (local_err) {
993         error_propagate(errp, local_err);
994         return;
995     }
996     prom = memory_region_get_ram_ptr(&s->prom);
997     checksum = 0;
998     for (i = 0; i < 6; i++) {
999         prom[i] = s->conf.macaddr.a[i];
1000         checksum += prom[i];
1001         if (checksum > 0xff) {
1002             checksum = (checksum + 1) & 0xff;
1003         }
1004     }
1005     prom[7] = 0xff - checksum;
1006 }
1007 
1008 static const VMStateDescription vmstate_dp8393x = {
1009     .name = "dp8393x",
1010     .version_id = 0,
1011     .minimum_version_id = 0,
1012     .fields = (VMStateField []) {
1013         VMSTATE_BUFFER_UNSAFE(cam, dp8393xState, 0, 16 * 6),
1014         VMSTATE_UINT16_ARRAY(regs, dp8393xState, 0x40),
1015         VMSTATE_END_OF_LIST()
1016     }
1017 };
1018 
1019 static Property dp8393x_properties[] = {
1020     DEFINE_NIC_PROPERTIES(dp8393xState, conf),
1021     DEFINE_PROP_LINK("dma_mr", dp8393xState, dma_mr,
1022                      TYPE_MEMORY_REGION, MemoryRegion *),
1023     DEFINE_PROP_UINT8("it_shift", dp8393xState, it_shift, 0),
1024     DEFINE_PROP_BOOL("big_endian", dp8393xState, big_endian, false),
1025     DEFINE_PROP_END_OF_LIST(),
1026 };
1027 
1028 static void dp8393x_class_init(ObjectClass *klass, void *data)
1029 {
1030     DeviceClass *dc = DEVICE_CLASS(klass);
1031 
1032     set_bit(DEVICE_CATEGORY_NETWORK, dc->categories);
1033     dc->realize = dp8393x_realize;
1034     dc->reset = dp8393x_reset;
1035     dc->vmsd = &vmstate_dp8393x;
1036     device_class_set_props(dc, dp8393x_properties);
1037 }
1038 
1039 static const TypeInfo dp8393x_info = {
1040     .name          = TYPE_DP8393X,
1041     .parent        = TYPE_SYS_BUS_DEVICE,
1042     .instance_size = sizeof(dp8393xState),
1043     .instance_init = dp8393x_instance_init,
1044     .class_init    = dp8393x_class_init,
1045 };
1046 
1047 static void dp8393x_register_types(void)
1048 {
1049     type_register_static(&dp8393x_info);
1050 }
1051 
1052 type_init(dp8393x_register_types)
1053