xref: /openbmc/qemu/hw/net/dp8393x.c (revision 4e6b1384)
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 
31 //#define DEBUG_SONIC
32 
33 #define SONIC_PROM_SIZE 0x1000
34 
35 #ifdef DEBUG_SONIC
36 #define DPRINTF(fmt, ...) \
37 do { printf("sonic: " fmt , ##  __VA_ARGS__); } while (0)
38 static const char* reg_names[] = {
39     "CR", "DCR", "RCR", "TCR", "IMR", "ISR", "UTDA", "CTDA",
40     "TPS", "TFC", "TSA0", "TSA1", "TFS", "URDA", "CRDA", "CRBA0",
41     "CRBA1", "RBWC0", "RBWC1", "EOBC", "URRA", "RSA", "REA", "RRP",
42     "RWP", "TRBA0", "TRBA1", "0x1b", "0x1c", "0x1d", "0x1e", "LLFA",
43     "TTDA", "CEP", "CAP2", "CAP1", "CAP0", "CE", "CDP", "CDC",
44     "SR", "WT0", "WT1", "RSC", "CRCT", "FAET", "MPT", "MDT",
45     "0x30", "0x31", "0x32", "0x33", "0x34", "0x35", "0x36", "0x37",
46     "0x38", "0x39", "0x3a", "0x3b", "0x3c", "0x3d", "0x3e", "DCR2" };
47 #else
48 #define DPRINTF(fmt, ...) do {} while (0)
49 #endif
50 
51 #define SONIC_ERROR(fmt, ...) \
52 do { printf("sonic ERROR: %s: " fmt, __func__ , ## __VA_ARGS__); } while (0)
53 
54 #define SONIC_CR     0x00
55 #define SONIC_DCR    0x01
56 #define SONIC_RCR    0x02
57 #define SONIC_TCR    0x03
58 #define SONIC_IMR    0x04
59 #define SONIC_ISR    0x05
60 #define SONIC_UTDA   0x06
61 #define SONIC_CTDA   0x07
62 #define SONIC_TPS    0x08
63 #define SONIC_TFC    0x09
64 #define SONIC_TSA0   0x0a
65 #define SONIC_TSA1   0x0b
66 #define SONIC_TFS    0x0c
67 #define SONIC_URDA   0x0d
68 #define SONIC_CRDA   0x0e
69 #define SONIC_CRBA0  0x0f
70 #define SONIC_CRBA1  0x10
71 #define SONIC_RBWC0  0x11
72 #define SONIC_RBWC1  0x12
73 #define SONIC_EOBC   0x13
74 #define SONIC_URRA   0x14
75 #define SONIC_RSA    0x15
76 #define SONIC_REA    0x16
77 #define SONIC_RRP    0x17
78 #define SONIC_RWP    0x18
79 #define SONIC_TRBA0  0x19
80 #define SONIC_TRBA1  0x1a
81 #define SONIC_LLFA   0x1f
82 #define SONIC_TTDA   0x20
83 #define SONIC_CEP    0x21
84 #define SONIC_CAP2   0x22
85 #define SONIC_CAP1   0x23
86 #define SONIC_CAP0   0x24
87 #define SONIC_CE     0x25
88 #define SONIC_CDP    0x26
89 #define SONIC_CDC    0x27
90 #define SONIC_SR     0x28
91 #define SONIC_WT0    0x29
92 #define SONIC_WT1    0x2a
93 #define SONIC_RSC    0x2b
94 #define SONIC_CRCT   0x2c
95 #define SONIC_FAET   0x2d
96 #define SONIC_MPT    0x2e
97 #define SONIC_MDT    0x2f
98 #define SONIC_DCR2   0x3f
99 
100 #define SONIC_CR_HTX     0x0001
101 #define SONIC_CR_TXP     0x0002
102 #define SONIC_CR_RXDIS   0x0004
103 #define SONIC_CR_RXEN    0x0008
104 #define SONIC_CR_STP     0x0010
105 #define SONIC_CR_ST      0x0020
106 #define SONIC_CR_RST     0x0080
107 #define SONIC_CR_RRRA    0x0100
108 #define SONIC_CR_LCAM    0x0200
109 #define SONIC_CR_MASK    0x03bf
110 
111 #define SONIC_DCR_DW     0x0020
112 #define SONIC_DCR_LBR    0x2000
113 #define SONIC_DCR_EXBUS  0x8000
114 
115 #define SONIC_RCR_PRX    0x0001
116 #define SONIC_RCR_LBK    0x0002
117 #define SONIC_RCR_FAER   0x0004
118 #define SONIC_RCR_CRCR   0x0008
119 #define SONIC_RCR_CRS    0x0020
120 #define SONIC_RCR_LPKT   0x0040
121 #define SONIC_RCR_BC     0x0080
122 #define SONIC_RCR_MC     0x0100
123 #define SONIC_RCR_LB0    0x0200
124 #define SONIC_RCR_LB1    0x0400
125 #define SONIC_RCR_AMC    0x0800
126 #define SONIC_RCR_PRO    0x1000
127 #define SONIC_RCR_BRD    0x2000
128 #define SONIC_RCR_RNT    0x4000
129 
130 #define SONIC_TCR_PTX    0x0001
131 #define SONIC_TCR_BCM    0x0002
132 #define SONIC_TCR_FU     0x0004
133 #define SONIC_TCR_EXC    0x0040
134 #define SONIC_TCR_CRSL   0x0080
135 #define SONIC_TCR_NCRS   0x0100
136 #define SONIC_TCR_EXD    0x0400
137 #define SONIC_TCR_CRCI   0x2000
138 #define SONIC_TCR_PINT   0x8000
139 
140 #define SONIC_ISR_RBE    0x0020
141 #define SONIC_ISR_RDE    0x0040
142 #define SONIC_ISR_TC     0x0080
143 #define SONIC_ISR_TXDN   0x0200
144 #define SONIC_ISR_PKTRX  0x0400
145 #define SONIC_ISR_PINT   0x0800
146 #define SONIC_ISR_LCD    0x1000
147 
148 #define TYPE_DP8393X "dp8393x"
149 #define DP8393X(obj) OBJECT_CHECK(dp8393xState, (obj), TYPE_DP8393X)
150 
151 typedef struct dp8393xState {
152     SysBusDevice parent_obj;
153 
154     /* Hardware */
155     uint8_t it_shift;
156     bool big_endian;
157     qemu_irq irq;
158 #ifdef DEBUG_SONIC
159     int irq_level;
160 #endif
161     QEMUTimer *watchdog;
162     int64_t wt_last_update;
163     NICConf conf;
164     NICState *nic;
165     MemoryRegion mmio;
166     MemoryRegion prom;
167 
168     /* Registers */
169     uint8_t cam[16][6];
170     uint16_t regs[0x40];
171 
172     /* Temporaries */
173     uint8_t tx_buffer[0x10000];
174     uint16_t data[12];
175     int loopback_packet;
176 
177     /* Memory access */
178     MemoryRegion *dma_mr;
179     AddressSpace as;
180 } dp8393xState;
181 
182 /* Accessor functions for values which are formed by
183  * concatenating two 16 bit device registers. By putting these
184  * in their own functions with a uint32_t return type we avoid the
185  * pitfall of implicit sign extension where ((x << 16) | y) is a
186  * signed 32 bit integer that might get sign-extended to a 64 bit integer.
187  */
188 static uint32_t dp8393x_cdp(dp8393xState *s)
189 {
190     return (s->regs[SONIC_URRA] << 16) | s->regs[SONIC_CDP];
191 }
192 
193 static uint32_t dp8393x_crba(dp8393xState *s)
194 {
195     return (s->regs[SONIC_CRBA1] << 16) | s->regs[SONIC_CRBA0];
196 }
197 
198 static uint32_t dp8393x_crda(dp8393xState *s)
199 {
200     return (s->regs[SONIC_URDA] << 16) | s->regs[SONIC_CRDA];
201 }
202 
203 static uint32_t dp8393x_rbwc(dp8393xState *s)
204 {
205     return (s->regs[SONIC_RBWC1] << 16) | s->regs[SONIC_RBWC0];
206 }
207 
208 static uint32_t dp8393x_rrp(dp8393xState *s)
209 {
210     return (s->regs[SONIC_URRA] << 16) | s->regs[SONIC_RRP];
211 }
212 
213 static uint32_t dp8393x_tsa(dp8393xState *s)
214 {
215     return (s->regs[SONIC_TSA1] << 16) | s->regs[SONIC_TSA0];
216 }
217 
218 static uint32_t dp8393x_ttda(dp8393xState *s)
219 {
220     return (s->regs[SONIC_UTDA] << 16) | s->regs[SONIC_TTDA];
221 }
222 
223 static uint32_t dp8393x_wt(dp8393xState *s)
224 {
225     return s->regs[SONIC_WT1] << 16 | s->regs[SONIC_WT0];
226 }
227 
228 static uint16_t dp8393x_get(dp8393xState *s, int width, int offset)
229 {
230     uint16_t val;
231 
232     if (s->big_endian) {
233         val = be16_to_cpu(s->data[offset * width + width - 1]);
234     } else {
235         val = le16_to_cpu(s->data[offset * width]);
236     }
237     return val;
238 }
239 
240 static void dp8393x_put(dp8393xState *s, int width, int offset,
241                         uint16_t val)
242 {
243     if (s->big_endian) {
244         s->data[offset * width + width - 1] = cpu_to_be16(val);
245     } else {
246         s->data[offset * width] = cpu_to_le16(val);
247     }
248 }
249 
250 static void dp8393x_update_irq(dp8393xState *s)
251 {
252     int level = (s->regs[SONIC_IMR] & s->regs[SONIC_ISR]) ? 1 : 0;
253 
254 #ifdef DEBUG_SONIC
255     if (level != s->irq_level) {
256         s->irq_level = level;
257         if (level) {
258             DPRINTF("raise irq, isr is 0x%04x\n", s->regs[SONIC_ISR]);
259         } else {
260             DPRINTF("lower irq\n");
261         }
262     }
263 #endif
264 
265     qemu_set_irq(s->irq, level);
266 }
267 
268 static void dp8393x_do_load_cam(dp8393xState *s)
269 {
270     int width, size;
271     uint16_t index = 0;
272 
273     width = (s->regs[SONIC_DCR] & SONIC_DCR_DW) ? 2 : 1;
274     size = sizeof(uint16_t) * 4 * width;
275 
276     while (s->regs[SONIC_CDC] & 0x1f) {
277         /* Fill current entry */
278         address_space_rw(&s->as, dp8393x_cdp(s),
279             MEMTXATTRS_UNSPECIFIED, (uint8_t *)s->data, size, 0);
280         s->cam[index][0] = dp8393x_get(s, width, 1) & 0xff;
281         s->cam[index][1] = dp8393x_get(s, width, 1) >> 8;
282         s->cam[index][2] = dp8393x_get(s, width, 2) & 0xff;
283         s->cam[index][3] = dp8393x_get(s, width, 2) >> 8;
284         s->cam[index][4] = dp8393x_get(s, width, 3) & 0xff;
285         s->cam[index][5] = dp8393x_get(s, width, 3) >> 8;
286         DPRINTF("load cam[%d] with %02x%02x%02x%02x%02x%02x\n", index,
287             s->cam[index][0], s->cam[index][1], s->cam[index][2],
288             s->cam[index][3], s->cam[index][4], s->cam[index][5]);
289         /* Move to next entry */
290         s->regs[SONIC_CDC]--;
291         s->regs[SONIC_CDP] += size;
292         index++;
293     }
294 
295     /* Read CAM enable */
296     address_space_rw(&s->as, dp8393x_cdp(s),
297         MEMTXATTRS_UNSPECIFIED, (uint8_t *)s->data, size, 0);
298     s->regs[SONIC_CE] = dp8393x_get(s, width, 0);
299     DPRINTF("load cam done. cam enable mask 0x%04x\n", s->regs[SONIC_CE]);
300 
301     /* Done */
302     s->regs[SONIC_CR] &= ~SONIC_CR_LCAM;
303     s->regs[SONIC_ISR] |= SONIC_ISR_LCD;
304     dp8393x_update_irq(s);
305 }
306 
307 static void dp8393x_do_read_rra(dp8393xState *s)
308 {
309     int width, size;
310 
311     /* Read memory */
312     width = (s->regs[SONIC_DCR] & SONIC_DCR_DW) ? 2 : 1;
313     size = sizeof(uint16_t) * 4 * width;
314     address_space_rw(&s->as, dp8393x_rrp(s),
315         MEMTXATTRS_UNSPECIFIED, (uint8_t *)s->data, size, 0);
316 
317     /* Update SONIC registers */
318     s->regs[SONIC_CRBA0] = dp8393x_get(s, width, 0);
319     s->regs[SONIC_CRBA1] = dp8393x_get(s, width, 1);
320     s->regs[SONIC_RBWC0] = dp8393x_get(s, width, 2);
321     s->regs[SONIC_RBWC1] = dp8393x_get(s, width, 3);
322     DPRINTF("CRBA0/1: 0x%04x/0x%04x, RBWC0/1: 0x%04x/0x%04x\n",
323         s->regs[SONIC_CRBA0], s->regs[SONIC_CRBA1],
324         s->regs[SONIC_RBWC0], s->regs[SONIC_RBWC1]);
325 
326     /* Go to next entry */
327     s->regs[SONIC_RRP] += size;
328 
329     /* Handle wrap */
330     if (s->regs[SONIC_RRP] == s->regs[SONIC_REA]) {
331         s->regs[SONIC_RRP] = s->regs[SONIC_RSA];
332     }
333 
334     /* Check resource exhaustion */
335     if (s->regs[SONIC_RRP] == s->regs[SONIC_RWP])
336     {
337         s->regs[SONIC_ISR] |= SONIC_ISR_RBE;
338         dp8393x_update_irq(s);
339     }
340 
341     /* Done */
342     s->regs[SONIC_CR] &= ~SONIC_CR_RRRA;
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 | SONIC_CR_HTX);
350     s->regs[SONIC_CR] |= SONIC_CR_RST | SONIC_CR_RXDIS;
351 }
352 
353 static void dp8393x_set_next_tick(dp8393xState *s)
354 {
355     uint32_t ticks;
356     int64_t delay;
357 
358     if (s->regs[SONIC_CR] & SONIC_CR_STP) {
359         timer_del(s->watchdog);
360         return;
361     }
362 
363     ticks = dp8393x_wt(s);
364     s->wt_last_update = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
365     delay = NANOSECONDS_PER_SECOND * ticks / 5000000;
366     timer_mod(s->watchdog, s->wt_last_update + delay);
367 }
368 
369 static void dp8393x_update_wt_regs(dp8393xState *s)
370 {
371     int64_t elapsed;
372     uint32_t val;
373 
374     if (s->regs[SONIC_CR] & SONIC_CR_STP) {
375         timer_del(s->watchdog);
376         return;
377     }
378 
379     elapsed = s->wt_last_update - qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
380     val = dp8393x_wt(s);
381     val -= elapsed / 5000000;
382     s->regs[SONIC_WT1] = (val >> 16) & 0xffff;
383     s->regs[SONIC_WT0] = (val >> 0)  & 0xffff;
384     dp8393x_set_next_tick(s);
385 
386 }
387 
388 static void dp8393x_do_start_timer(dp8393xState *s)
389 {
390     s->regs[SONIC_CR] &= ~SONIC_CR_STP;
391     dp8393x_set_next_tick(s);
392 }
393 
394 static void dp8393x_do_stop_timer(dp8393xState *s)
395 {
396     s->regs[SONIC_CR] &= ~SONIC_CR_ST;
397     dp8393x_update_wt_regs(s);
398 }
399 
400 static int dp8393x_can_receive(NetClientState *nc);
401 
402 static void dp8393x_do_receiver_enable(dp8393xState *s)
403 {
404     s->regs[SONIC_CR] &= ~SONIC_CR_RXDIS;
405     if (dp8393x_can_receive(s->nic->ncs)) {
406         qemu_flush_queued_packets(qemu_get_queue(s->nic));
407     }
408 }
409 
410 static void dp8393x_do_receiver_disable(dp8393xState *s)
411 {
412     s->regs[SONIC_CR] &= ~SONIC_CR_RXEN;
413 }
414 
415 static void dp8393x_do_transmit_packets(dp8393xState *s)
416 {
417     NetClientState *nc = qemu_get_queue(s->nic);
418     int width, size;
419     int tx_len, len;
420     uint16_t i;
421 
422     width = (s->regs[SONIC_DCR] & SONIC_DCR_DW) ? 2 : 1;
423 
424     while (1) {
425         /* Read memory */
426         size = sizeof(uint16_t) * 6 * width;
427         s->regs[SONIC_TTDA] = s->regs[SONIC_CTDA];
428         DPRINTF("Transmit packet at %08x\n", dp8393x_ttda(s));
429         address_space_rw(&s->as, dp8393x_ttda(s) + sizeof(uint16_t) * width,
430             MEMTXATTRS_UNSPECIFIED, (uint8_t *)s->data, size, 0);
431         tx_len = 0;
432 
433         /* Update registers */
434         s->regs[SONIC_TCR] = dp8393x_get(s, width, 0) & 0xf000;
435         s->regs[SONIC_TPS] = dp8393x_get(s, width, 1);
436         s->regs[SONIC_TFC] = dp8393x_get(s, width, 2);
437         s->regs[SONIC_TSA0] = dp8393x_get(s, width, 3);
438         s->regs[SONIC_TSA1] = dp8393x_get(s, width, 4);
439         s->regs[SONIC_TFS] = dp8393x_get(s, width, 5);
440 
441         /* Handle programmable interrupt */
442         if (s->regs[SONIC_TCR] & SONIC_TCR_PINT) {
443             s->regs[SONIC_ISR] |= SONIC_ISR_PINT;
444         } else {
445             s->regs[SONIC_ISR] &= ~SONIC_ISR_PINT;
446         }
447 
448         for (i = 0; i < s->regs[SONIC_TFC]; ) {
449             /* Append fragment */
450             len = s->regs[SONIC_TFS];
451             if (tx_len + len > sizeof(s->tx_buffer)) {
452                 len = sizeof(s->tx_buffer) - tx_len;
453             }
454             address_space_rw(&s->as, dp8393x_tsa(s),
455                 MEMTXATTRS_UNSPECIFIED, &s->tx_buffer[tx_len], len, 0);
456             tx_len += len;
457 
458             i++;
459             if (i != s->regs[SONIC_TFC]) {
460                 /* Read next fragment details */
461                 size = sizeof(uint16_t) * 3 * width;
462                 address_space_rw(&s->as,
463                     dp8393x_ttda(s) + sizeof(uint16_t) * (4 + 3 * i) * width,
464                     MEMTXATTRS_UNSPECIFIED, (uint8_t *)s->data, size, 0);
465                 s->regs[SONIC_TSA0] = dp8393x_get(s, width, 0);
466                 s->regs[SONIC_TSA1] = dp8393x_get(s, width, 1);
467                 s->regs[SONIC_TFS] = dp8393x_get(s, width, 2);
468             }
469         }
470 
471         /* Handle Ethernet checksum */
472         if (!(s->regs[SONIC_TCR] & SONIC_TCR_CRCI)) {
473             /* Don't append FCS there, to look like slirp packets
474              * which don't have one */
475         } else {
476             /* Remove existing FCS */
477             tx_len -= 4;
478         }
479 
480         if (s->regs[SONIC_RCR] & (SONIC_RCR_LB1 | SONIC_RCR_LB0)) {
481             /* Loopback */
482             s->regs[SONIC_TCR] |= SONIC_TCR_CRSL;
483             if (nc->info->can_receive(nc)) {
484                 s->loopback_packet = 1;
485                 nc->info->receive(nc, s->tx_buffer, tx_len);
486             }
487         } else {
488             /* Transmit packet */
489             qemu_send_packet(nc, s->tx_buffer, tx_len);
490         }
491         s->regs[SONIC_TCR] |= SONIC_TCR_PTX;
492 
493         /* Write status */
494         dp8393x_put(s, width, 0,
495                     s->regs[SONIC_TCR] & 0x0fff); /* status */
496         size = sizeof(uint16_t) * width;
497         address_space_rw(&s->as,
498             dp8393x_ttda(s),
499             MEMTXATTRS_UNSPECIFIED, (uint8_t *)s->data, size, 1);
500 
501         if (!(s->regs[SONIC_CR] & SONIC_CR_HTX)) {
502             /* Read footer of packet */
503             size = sizeof(uint16_t) * width;
504             address_space_rw(&s->as,
505                 dp8393x_ttda(s) +
506                              sizeof(uint16_t) *
507                              (4 + 3 * s->regs[SONIC_TFC]) * width,
508                 MEMTXATTRS_UNSPECIFIED, (uint8_t *)s->data, size, 0);
509             s->regs[SONIC_CTDA] = dp8393x_get(s, width, 0) & ~0x1;
510             if (dp8393x_get(s, width, 0) & 0x1) {
511                 /* EOL detected */
512                 break;
513             }
514         }
515     }
516 
517     /* Done */
518     s->regs[SONIC_CR] &= ~SONIC_CR_TXP;
519     s->regs[SONIC_ISR] |= SONIC_ISR_TXDN;
520     dp8393x_update_irq(s);
521 }
522 
523 static void dp8393x_do_halt_transmission(dp8393xState *s)
524 {
525     /* Nothing to do */
526 }
527 
528 static void dp8393x_do_command(dp8393xState *s, uint16_t command)
529 {
530     if ((s->regs[SONIC_CR] & SONIC_CR_RST) && !(command & SONIC_CR_RST)) {
531         s->regs[SONIC_CR] &= ~SONIC_CR_RST;
532         return;
533     }
534 
535     s->regs[SONIC_CR] |= (command & SONIC_CR_MASK);
536 
537     if (command & SONIC_CR_HTX)
538         dp8393x_do_halt_transmission(s);
539     if (command & SONIC_CR_TXP)
540         dp8393x_do_transmit_packets(s);
541     if (command & SONIC_CR_RXDIS)
542         dp8393x_do_receiver_disable(s);
543     if (command & SONIC_CR_RXEN)
544         dp8393x_do_receiver_enable(s);
545     if (command & SONIC_CR_STP)
546         dp8393x_do_stop_timer(s);
547     if (command & SONIC_CR_ST)
548         dp8393x_do_start_timer(s);
549     if (command & SONIC_CR_RST)
550         dp8393x_do_software_reset(s);
551     if (command & SONIC_CR_RRRA)
552         dp8393x_do_read_rra(s);
553     if (command & SONIC_CR_LCAM)
554         dp8393x_do_load_cam(s);
555 }
556 
557 static uint64_t dp8393x_read(void *opaque, hwaddr addr, unsigned int size)
558 {
559     dp8393xState *s = opaque;
560     int reg = addr >> s->it_shift;
561     uint16_t val = 0;
562 
563     switch (reg) {
564         /* Update data before reading it */
565         case SONIC_WT0:
566         case SONIC_WT1:
567             dp8393x_update_wt_regs(s);
568             val = s->regs[reg];
569             break;
570         /* Accept read to some registers only when in reset mode */
571         case SONIC_CAP2:
572         case SONIC_CAP1:
573         case SONIC_CAP0:
574             if (s->regs[SONIC_CR] & SONIC_CR_RST) {
575                 val = s->cam[s->regs[SONIC_CEP] & 0xf][2* (SONIC_CAP0 - reg) + 1] << 8;
576                 val |= s->cam[s->regs[SONIC_CEP] & 0xf][2* (SONIC_CAP0 - reg)];
577             }
578             break;
579         /* All other registers have no special contrainst */
580         default:
581             val = s->regs[reg];
582     }
583 
584     DPRINTF("read 0x%04x from reg %s\n", val, reg_names[reg]);
585 
586     return val;
587 }
588 
589 static void dp8393x_write(void *opaque, hwaddr addr, uint64_t data,
590                           unsigned int size)
591 {
592     dp8393xState *s = opaque;
593     int reg = addr >> s->it_shift;
594 
595     DPRINTF("write 0x%04x to reg %s\n", (uint16_t)data, reg_names[reg]);
596 
597     switch (reg) {
598         /* Command register */
599         case SONIC_CR:
600             dp8393x_do_command(s, data);
601             break;
602         /* Prevent write to read-only registers */
603         case SONIC_CAP2:
604         case SONIC_CAP1:
605         case SONIC_CAP0:
606         case SONIC_SR:
607         case SONIC_MDT:
608             DPRINTF("writing to reg %d invalid\n", reg);
609             break;
610         /* Accept write to some registers only when in reset mode */
611         case SONIC_DCR:
612             if (s->regs[SONIC_CR] & SONIC_CR_RST) {
613                 s->regs[reg] = data & 0xbfff;
614             } else {
615                 DPRINTF("writing to DCR invalid\n");
616             }
617             break;
618         case SONIC_DCR2:
619             if (s->regs[SONIC_CR] & SONIC_CR_RST) {
620                 s->regs[reg] = data & 0xf017;
621             } else {
622                 DPRINTF("writing to DCR2 invalid\n");
623             }
624             break;
625         /* 12 lower bytes are Read Only */
626         case SONIC_TCR:
627             s->regs[reg] = data & 0xf000;
628             break;
629         /* 9 lower bytes are Read Only */
630         case SONIC_RCR:
631             s->regs[reg] = data & 0xffe0;
632             break;
633         /* Ignore most significant bit */
634         case SONIC_IMR:
635             s->regs[reg] = data & 0x7fff;
636             dp8393x_update_irq(s);
637             break;
638         /* Clear bits by writing 1 to them */
639         case SONIC_ISR:
640             data &= s->regs[reg];
641             s->regs[reg] &= ~data;
642             if (data & SONIC_ISR_RBE) {
643                 dp8393x_do_read_rra(s);
644             }
645             dp8393x_update_irq(s);
646             if (dp8393x_can_receive(s->nic->ncs)) {
647                 qemu_flush_queued_packets(qemu_get_queue(s->nic));
648             }
649             break;
650         /* Ignore least significant bit */
651         case SONIC_RSA:
652         case SONIC_REA:
653         case SONIC_RRP:
654         case SONIC_RWP:
655             s->regs[reg] = data & 0xfffe;
656             break;
657         /* Invert written value for some registers */
658         case SONIC_CRCT:
659         case SONIC_FAET:
660         case SONIC_MPT:
661             s->regs[reg] = data ^ 0xffff;
662             break;
663         /* All other registers have no special contrainst */
664         default:
665             s->regs[reg] = data;
666     }
667 
668     if (reg == SONIC_WT0 || reg == SONIC_WT1) {
669         dp8393x_set_next_tick(s);
670     }
671 }
672 
673 static const MemoryRegionOps dp8393x_ops = {
674     .read = dp8393x_read,
675     .write = dp8393x_write,
676     .impl.min_access_size = 2,
677     .impl.max_access_size = 2,
678     .endianness = DEVICE_NATIVE_ENDIAN,
679 };
680 
681 static void dp8393x_watchdog(void *opaque)
682 {
683     dp8393xState *s = opaque;
684 
685     if (s->regs[SONIC_CR] & SONIC_CR_STP) {
686         return;
687     }
688 
689     s->regs[SONIC_WT1] = 0xffff;
690     s->regs[SONIC_WT0] = 0xffff;
691     dp8393x_set_next_tick(s);
692 
693     /* Signal underflow */
694     s->regs[SONIC_ISR] |= SONIC_ISR_TC;
695     dp8393x_update_irq(s);
696 }
697 
698 static int dp8393x_can_receive(NetClientState *nc)
699 {
700     dp8393xState *s = qemu_get_nic_opaque(nc);
701 
702     if (!(s->regs[SONIC_CR] & SONIC_CR_RXEN))
703         return 0;
704     if (s->regs[SONIC_ISR] & SONIC_ISR_RBE)
705         return 0;
706     return 1;
707 }
708 
709 static int dp8393x_receive_filter(dp8393xState *s, const uint8_t * buf,
710                                   int size)
711 {
712     static const uint8_t bcast[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
713     int i;
714 
715     /* Check promiscuous mode */
716     if ((s->regs[SONIC_RCR] & SONIC_RCR_PRO) && (buf[0] & 1) == 0) {
717         return 0;
718     }
719 
720     /* Check multicast packets */
721     if ((s->regs[SONIC_RCR] & SONIC_RCR_AMC) && (buf[0] & 1) == 1) {
722         return SONIC_RCR_MC;
723     }
724 
725     /* Check broadcast */
726     if ((s->regs[SONIC_RCR] & SONIC_RCR_BRD) && !memcmp(buf, bcast, sizeof(bcast))) {
727         return SONIC_RCR_BC;
728     }
729 
730     /* Check CAM */
731     for (i = 0; i < 16; i++) {
732         if (s->regs[SONIC_CE] & (1 << i)) {
733              /* Entry enabled */
734              if (!memcmp(buf, s->cam[i], sizeof(s->cam[i]))) {
735                  return 0;
736              }
737         }
738     }
739 
740     return -1;
741 }
742 
743 static ssize_t dp8393x_receive(NetClientState *nc, const uint8_t * buf,
744                                size_t size)
745 {
746     dp8393xState *s = qemu_get_nic_opaque(nc);
747     int packet_type;
748     uint32_t available, address;
749     int width, rx_len = size;
750     uint32_t checksum;
751 
752     width = (s->regs[SONIC_DCR] & SONIC_DCR_DW) ? 2 : 1;
753 
754     s->regs[SONIC_RCR] &= ~(SONIC_RCR_PRX | SONIC_RCR_LBK | SONIC_RCR_FAER |
755         SONIC_RCR_CRCR | SONIC_RCR_LPKT | SONIC_RCR_BC | SONIC_RCR_MC);
756 
757     packet_type = dp8393x_receive_filter(s, buf, size);
758     if (packet_type < 0) {
759         DPRINTF("packet not for netcard\n");
760         return -1;
761     }
762 
763     /* XXX: Check byte ordering */
764 
765     /* Check for EOL */
766     if (s->regs[SONIC_LLFA] & 0x1) {
767         /* Are we still in resource exhaustion? */
768         size = sizeof(uint16_t) * 1 * width;
769         address = dp8393x_crda(s) + sizeof(uint16_t) * 5 * width;
770         address_space_rw(&s->as, address, MEMTXATTRS_UNSPECIFIED,
771                          (uint8_t *)s->data, size, 0);
772         if (dp8393x_get(s, width, 0) & 0x1) {
773             /* Still EOL ; stop reception */
774             return -1;
775         } else {
776             s->regs[SONIC_CRDA] = s->regs[SONIC_LLFA];
777         }
778     }
779 
780     /* Save current position */
781     s->regs[SONIC_TRBA1] = s->regs[SONIC_CRBA1];
782     s->regs[SONIC_TRBA0] = s->regs[SONIC_CRBA0];
783 
784     /* Calculate the ethernet checksum */
785     checksum = cpu_to_le32(crc32(0, buf, rx_len));
786 
787     /* Put packet into RBA */
788     DPRINTF("Receive packet at %08x\n", dp8393x_crba(s));
789     address = dp8393x_crba(s);
790     address_space_rw(&s->as, address,
791         MEMTXATTRS_UNSPECIFIED, (uint8_t *)buf, rx_len, 1);
792     address += rx_len;
793     address_space_rw(&s->as, address,
794         MEMTXATTRS_UNSPECIFIED, (uint8_t *)&checksum, 4, 1);
795     rx_len += 4;
796     s->regs[SONIC_CRBA1] = address >> 16;
797     s->regs[SONIC_CRBA0] = address & 0xffff;
798     available = dp8393x_rbwc(s);
799     available -= rx_len / 2;
800     s->regs[SONIC_RBWC1] = available >> 16;
801     s->regs[SONIC_RBWC0] = available & 0xffff;
802 
803     /* Update status */
804     if (dp8393x_rbwc(s) < s->regs[SONIC_EOBC]) {
805         s->regs[SONIC_RCR] |= SONIC_RCR_LPKT;
806     }
807     s->regs[SONIC_RCR] |= packet_type;
808     s->regs[SONIC_RCR] |= SONIC_RCR_PRX;
809     if (s->loopback_packet) {
810         s->regs[SONIC_RCR] |= SONIC_RCR_LBK;
811         s->loopback_packet = 0;
812     }
813 
814     /* Write status to memory */
815     DPRINTF("Write status at %08x\n", dp8393x_crda(s));
816     dp8393x_put(s, width, 0, s->regs[SONIC_RCR]); /* status */
817     dp8393x_put(s, width, 1, rx_len); /* byte count */
818     dp8393x_put(s, width, 2, s->regs[SONIC_TRBA0]); /* pkt_ptr0 */
819     dp8393x_put(s, width, 3, s->regs[SONIC_TRBA1]); /* pkt_ptr1 */
820     dp8393x_put(s, width, 4, s->regs[SONIC_RSC]); /* seq_no */
821     size = sizeof(uint16_t) * 5 * width;
822     address_space_rw(&s->as, dp8393x_crda(s),
823         MEMTXATTRS_UNSPECIFIED, (uint8_t *)s->data, size, 1);
824 
825     /* Move to next descriptor */
826     size = sizeof(uint16_t) * width;
827     address_space_rw(&s->as, dp8393x_crda(s) + sizeof(uint16_t) * 5 * width,
828         MEMTXATTRS_UNSPECIFIED, (uint8_t *)s->data, size, 0);
829     s->regs[SONIC_LLFA] = dp8393x_get(s, width, 0);
830     if (s->regs[SONIC_LLFA] & 0x1) {
831         /* EOL detected */
832         s->regs[SONIC_ISR] |= SONIC_ISR_RDE;
833     } else {
834         /* Clear in_use, but it is always 16bit wide */
835         int offset = dp8393x_crda(s) + sizeof(uint16_t) * 6 * width;
836         if (s->big_endian && width == 2) {
837             /* we need to adjust the offset of the 16bit field */
838             offset += sizeof(uint16_t);
839         }
840         s->data[0] = 0;
841         address_space_rw(&s->as, offset, MEMTXATTRS_UNSPECIFIED,
842                          (uint8_t *)s->data, sizeof(uint16_t), 1);
843         s->regs[SONIC_CRDA] = s->regs[SONIC_LLFA];
844         s->regs[SONIC_ISR] |= SONIC_ISR_PKTRX;
845         s->regs[SONIC_RSC] = (s->regs[SONIC_RSC] & 0xff00) | (((s->regs[SONIC_RSC] & 0x00ff) + 1) & 0x00ff);
846 
847         if (s->regs[SONIC_RCR] & SONIC_RCR_LPKT) {
848             /* Read next RRA */
849             dp8393x_do_read_rra(s);
850         }
851     }
852 
853     /* Done */
854     dp8393x_update_irq(s);
855 
856     return size;
857 }
858 
859 static void dp8393x_reset(DeviceState *dev)
860 {
861     dp8393xState *s = DP8393X(dev);
862     timer_del(s->watchdog);
863 
864     memset(s->regs, 0, sizeof(s->regs));
865     s->regs[SONIC_CR] = SONIC_CR_RST | SONIC_CR_STP | SONIC_CR_RXDIS;
866     s->regs[SONIC_DCR] &= ~(SONIC_DCR_EXBUS | SONIC_DCR_LBR);
867     s->regs[SONIC_RCR] &= ~(SONIC_RCR_LB0 | SONIC_RCR_LB1 | SONIC_RCR_BRD | SONIC_RCR_RNT);
868     s->regs[SONIC_TCR] |= SONIC_TCR_NCRS | SONIC_TCR_PTX;
869     s->regs[SONIC_TCR] &= ~SONIC_TCR_BCM;
870     s->regs[SONIC_IMR] = 0;
871     s->regs[SONIC_ISR] = 0;
872     s->regs[SONIC_DCR2] = 0;
873     s->regs[SONIC_EOBC] = 0x02F8;
874     s->regs[SONIC_RSC] = 0;
875     s->regs[SONIC_CE] = 0;
876     s->regs[SONIC_RSC] = 0;
877 
878     /* Network cable is connected */
879     s->regs[SONIC_RCR] |= SONIC_RCR_CRS;
880 
881     dp8393x_update_irq(s);
882 }
883 
884 static NetClientInfo net_dp83932_info = {
885     .type = NET_CLIENT_DRIVER_NIC,
886     .size = sizeof(NICState),
887     .can_receive = dp8393x_can_receive,
888     .receive = dp8393x_receive,
889 };
890 
891 static void dp8393x_instance_init(Object *obj)
892 {
893     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
894     dp8393xState *s = DP8393X(obj);
895 
896     sysbus_init_mmio(sbd, &s->mmio);
897     sysbus_init_mmio(sbd, &s->prom);
898     sysbus_init_irq(sbd, &s->irq);
899 }
900 
901 static void dp8393x_realize(DeviceState *dev, Error **errp)
902 {
903     dp8393xState *s = DP8393X(dev);
904     int i, checksum;
905     uint8_t *prom;
906     Error *local_err = NULL;
907 
908     address_space_init(&s->as, s->dma_mr, "dp8393x");
909     memory_region_init_io(&s->mmio, OBJECT(dev), &dp8393x_ops, s,
910                           "dp8393x-regs", 0x40 << s->it_shift);
911 
912     s->nic = qemu_new_nic(&net_dp83932_info, &s->conf,
913                           object_get_typename(OBJECT(dev)), dev->id, s);
914     qemu_format_nic_info_str(qemu_get_queue(s->nic), s->conf.macaddr.a);
915 
916     s->watchdog = timer_new_ns(QEMU_CLOCK_VIRTUAL, dp8393x_watchdog, s);
917     s->regs[SONIC_SR] = 0x0004; /* only revision recognized by Linux */
918 
919     memory_region_init_ram(&s->prom, OBJECT(dev),
920                            "dp8393x-prom", SONIC_PROM_SIZE, &local_err);
921     if (local_err) {
922         error_propagate(errp, local_err);
923         return;
924     }
925     memory_region_set_readonly(&s->prom, true);
926     prom = memory_region_get_ram_ptr(&s->prom);
927     checksum = 0;
928     for (i = 0; i < 6; i++) {
929         prom[i] = s->conf.macaddr.a[i];
930         checksum += prom[i];
931         if (checksum > 0xff) {
932             checksum = (checksum + 1) & 0xff;
933         }
934     }
935     prom[7] = 0xff - checksum;
936 }
937 
938 static const VMStateDescription vmstate_dp8393x = {
939     .name = "dp8393x",
940     .version_id = 0,
941     .minimum_version_id = 0,
942     .fields = (VMStateField []) {
943         VMSTATE_BUFFER_UNSAFE(cam, dp8393xState, 0, 16 * 6),
944         VMSTATE_UINT16_ARRAY(regs, dp8393xState, 0x40),
945         VMSTATE_END_OF_LIST()
946     }
947 };
948 
949 static Property dp8393x_properties[] = {
950     DEFINE_NIC_PROPERTIES(dp8393xState, conf),
951     DEFINE_PROP_LINK("dma_mr", dp8393xState, dma_mr,
952                      TYPE_MEMORY_REGION, MemoryRegion *),
953     DEFINE_PROP_UINT8("it_shift", dp8393xState, it_shift, 0),
954     DEFINE_PROP_BOOL("big_endian", dp8393xState, big_endian, false),
955     DEFINE_PROP_END_OF_LIST(),
956 };
957 
958 static void dp8393x_class_init(ObjectClass *klass, void *data)
959 {
960     DeviceClass *dc = DEVICE_CLASS(klass);
961 
962     set_bit(DEVICE_CATEGORY_NETWORK, dc->categories);
963     dc->realize = dp8393x_realize;
964     dc->reset = dp8393x_reset;
965     dc->vmsd = &vmstate_dp8393x;
966     dc->props = dp8393x_properties;
967 }
968 
969 static const TypeInfo dp8393x_info = {
970     .name          = TYPE_DP8393X,
971     .parent        = TYPE_SYS_BUS_DEVICE,
972     .instance_size = sizeof(dp8393xState),
973     .instance_init = dp8393x_instance_init,
974     .class_init    = dp8393x_class_init,
975 };
976 
977 static void dp8393x_register_types(void)
978 {
979     type_register_static(&dp8393x_info);
980 }
981 
982 type_init(dp8393x_register_types)
983