Statistics
| Branch: | Revision:

root / hw / smc91c111.c @ 687fa640

History | View | Annotate | Download (18.9 kB)

1
/* 
2
 * SMSC 91C111 Ethernet interface emulation
3
 *
4
 * Copyright (c) 2005 CodeSourcery, LLC.
5
 * Written by Paul Brook
6
 *
7
 * This code is licenced under the GPL
8
 */
9

    
10
#include "vl.h"
11
/* For crc32 */
12
#include <zlib.h>
13

    
14
/* Number of 2k memory pages available.  */
15
#define NUM_PACKETS 4
16

    
17
typedef struct {
18
    uint32_t base;
19
    VLANClientState *vc;
20
    uint16_t tcr;
21
    uint16_t rcr;
22
    uint16_t cr;
23
    uint16_t ctr;
24
    uint16_t gpr;
25
    uint16_t ptr;
26
    uint16_t ercv;
27
    void *pic;
28
    int irq;
29
    int bank;
30
    int packet_num;
31
    int tx_alloc;
32
    /* Bitmask of allocated packets.  */
33
    int allocated;
34
    int tx_fifo_len;
35
    int tx_fifo[NUM_PACKETS];
36
    int rx_fifo_len;
37
    int rx_fifo[NUM_PACKETS];
38
    int tx_fifo_done_len;
39
    int tx_fifo_done[NUM_PACKETS];
40
    /* Packet buffer memory.  */
41
    uint8_t data[NUM_PACKETS][2048];
42
    uint8_t int_level;
43
    uint8_t int_mask;
44
    uint8_t macaddr[6];
45
} smc91c111_state;
46

    
47
#define RCR_SOFT_RST  0x8000
48
#define RCR_STRIP_CRC 0x0200
49
#define RCR_RXEN      0x0100
50

    
51
#define TCR_EPH_LOOP  0x2000
52
#define TCR_NOCRC     0x0100
53
#define TCR_PAD_EN    0x0080
54
#define TCR_FORCOL    0x0004
55
#define TCR_LOOP      0x0002
56
#define TCR_TXEN      0x0001
57

    
58
#define INT_MD        0x80
59
#define INT_ERCV      0x40
60
#define INT_EPH       0x20
61
#define INT_RX_OVRN   0x10
62
#define INT_ALLOC     0x08
63
#define INT_TX_EMPTY  0x04
64
#define INT_TX        0x02
65
#define INT_RCV       0x01
66

    
67
#define CTR_AUTO_RELEASE  0x0800
68
#define CTR_RELOAD        0x0002
69
#define CTR_STORE         0x0001
70

    
71
#define RS_ALGNERR      0x8000
72
#define RS_BRODCAST     0x4000
73
#define RS_BADCRC       0x2000
74
#define RS_ODDFRAME     0x1000
75
#define RS_TOOLONG      0x0800
76
#define RS_TOOSHORT     0x0400
77
#define RS_MULTICAST    0x0001
78

    
79
/* Update interrupt status.  */
80
static void smc91c111_update(smc91c111_state *s)
81
{
82
    int level;
83

    
84
    if (s->tx_fifo_len == 0)
85
        s->int_level |= INT_TX_EMPTY;
86
    if (s->tx_fifo_done_len != 0)
87
        s->int_level |= INT_TX;
88
    level = (s->int_level & s->int_mask) != 0;
89
    pic_set_irq_new(s->pic, s->irq, level);
90
}
91

    
92
/* Try to allocate a packet.  Returns 0x80 on failure.  */
93
static int smc91c111_allocate_packet(smc91c111_state *s)
94
{
95
    int i;
96
    if (s->allocated == (1 << NUM_PACKETS) - 1) {
97
        return 0x80;
98
    }
99

    
100
    for (i = 0; i < NUM_PACKETS; i++) {
101
        if ((s->allocated & (1 << i)) == 0)
102
            break;
103
    }
104
    s->allocated |= 1 << i;
105
    return i;
106
}
107

    
108

    
109
/* Process a pending TX allocate.  */
110
static void smc91c111_tx_alloc(smc91c111_state *s)
111
{
112
    s->tx_alloc = smc91c111_allocate_packet(s);
113
    if (s->tx_alloc == 0x80)
114
        return;
115
    s->int_level |= INT_ALLOC;
116
    smc91c111_update(s);
117
}
118

    
119
/* Remove and item from the RX FIFO.  */
120
static void smc91c111_pop_rx_fifo(smc91c111_state *s)
121
{
122
    int i;
123

    
124
    s->rx_fifo_len--;
125
    if (s->rx_fifo_len) {
126
        for (i = 0; i < s->rx_fifo_len; i++)
127
            s->rx_fifo[i] = s->rx_fifo[i + 1];
128
        s->int_level |= INT_RCV;
129
    } else {
130
        s->int_level &= ~INT_RCV;
131
    }
132
    smc91c111_update(s);
133
}
134

    
135
/* Remove an item from the TX completion FIFO.  */
136
static void smc91c111_pop_tx_fifo_done(smc91c111_state *s)
137
{
138
    int i;
139

    
140
    if (s->tx_fifo_done_len == 0)
141
        return;
142
    s->tx_fifo_done_len--;
143
    for (i = 0; i < s->tx_fifo_done_len; i++)
144
        s->tx_fifo_done[i] = s->tx_fifo_done[i + 1];
145
}
146

    
147
/* Release the memory allocated to a packet.  */
148
static void smc91c111_release_packet(smc91c111_state *s, int packet)
149
{
150
    s->allocated &= ~(1 << packet);
151
    if (s->tx_alloc == 0x80)
152
        smc91c111_tx_alloc(s);
153
}
154

    
155
/* Flush the TX FIFO.  */
156
static void smc91c111_do_tx(smc91c111_state *s)
157
{
158
    int i;
159
    int len;
160
    int control;
161
    int add_crc;
162
    int packetnum;
163
    uint8_t *p;
164

    
165
    if ((s->tcr & TCR_TXEN) == 0)
166
        return;
167
    if (s->tx_fifo_len == 0)
168
        return;
169
    for (i = 0; i < s->tx_fifo_len; i++) {
170
        packetnum = s->tx_fifo[i];
171
        p = &s->data[packetnum][0];
172
        /* Set status word.  */
173
        *(p++) = 0x01;
174
        *(p++) = 0x40;
175
        len = *(p++);
176
        len |= ((int)*(p++)) << 8;
177
        len -= 6;
178
        control = p[len + 1];
179
        if (control & 0x20)
180
            len++;
181
        /* ??? This overwrites the data following the buffer.
182
           Don't know what real hardware does.  */
183
        if (len < 64 && (s->tcr & TCR_PAD_EN)) {
184
            memset(p + len, 0, 64 - len);
185
            len = 64;
186
        }
187
#if 0
188
        /* The card is supposed to append the CRC to the frame.  However
189
           none of the other network traffic has the CRC appended.
190
           Suspect this is low level ethernet detail we don't need to worry
191
           about.  */
192
        add_crc = (control & 0x10) || (s->tcr & TCR_NOCRC) == 0;
193
        if (add_crc) {
194
            uint32_t crc;
195

196
            crc = crc32(~0, p, len);
197
            memcpy(p + len, &crc, 4);
198
            len += 4;
199
        }
200
#else
201
        add_crc = 0;
202
#endif
203
        if (s->ctr & CTR_AUTO_RELEASE)
204
            /* Race?  */
205
            smc91c111_release_packet(s, packetnum);
206
        else if (s->tx_fifo_done_len < NUM_PACKETS)
207
            s->tx_fifo_done[s->tx_fifo_done_len++] = packetnum;
208
        qemu_send_packet(s->vc, p, len);
209
    }
210
    s->tx_fifo_len = 0;
211
    smc91c111_update(s);
212
}
213

    
214
/* Add a packet to the TX FIFO.  */
215
static void smc91c111_queue_tx(smc91c111_state *s, int packet)
216
{
217
    if (s->tx_fifo_len == NUM_PACKETS)
218
        return;
219
    s->tx_fifo[s->tx_fifo_len++] = packet;
220
    smc91c111_do_tx(s);
221
}
222

    
223
static void smc91c111_reset(smc91c111_state *s)
224
{
225
    s->bank = 0;
226
    s->tx_fifo_len = 0;
227
    s->tx_fifo_done_len = 0;
228
    s->rx_fifo_len = 0;
229
    s->allocated = 0;
230
    s->packet_num = 0;
231
    s->tx_alloc = 0;
232
    s->tcr = 0;
233
    s->rcr = 0;
234
    s->cr = 0xa0b1;
235
    s->ctr = 0x1210;
236
    s->ptr = 0;
237
    s->ercv = 0x1f;
238
    s->int_level = INT_TX_EMPTY;
239
    s->int_mask = 0;
240
    smc91c111_update(s);
241
}
242

    
243
#define SET_LOW(name, val) s->name = (s->name & 0xff00) | val
244
#define SET_HIGH(name, val) s->name = (s->name & 0xff) | (val << 8)
245

    
246
static void smc91c111_writeb(void *opaque, target_phys_addr_t offset,
247
                             uint32_t value)
248
{
249
    smc91c111_state *s = (smc91c111_state *)opaque;
250

    
251
    offset -= s->base;
252
    if (offset == 14) {
253
        s->bank = value;
254
        return;
255
    }
256
    if (offset == 15)
257
        return;
258
    switch (s->bank) {
259
    case 0:
260
        switch (offset) {
261
        case 0: /* TCR */
262
            SET_LOW(tcr, value);
263
            return;
264
        case 1:
265
            SET_HIGH(tcr, value);
266
            return;
267
        case 4: /* RCR */
268
            SET_LOW(rcr, value);
269
            return;
270
        case 5:
271
            SET_HIGH(rcr, value);
272
            if (s->rcr & RCR_SOFT_RST)
273
                smc91c111_reset(s);
274
            return;
275
        case 10: case 11: /* RPCR */
276
            /* Ignored */
277
            return;
278
        }
279
        break;
280

    
281
    case 1:
282
        switch (offset) {
283
        case 0: /* CONFIG */
284
            SET_LOW(cr, value);
285
            return;
286
        case 1:
287
            SET_HIGH(cr,value);
288
            return;
289
        case 2: case 3: /* BASE */
290
        case 4: case 5: case 6: case 7: case 8: case 9: /* IA */
291
            /* Not implemented.  */
292
            return;
293
        case 10: /* Genral Purpose */
294
            SET_LOW(gpr, value);
295
            return;
296
        case 11:
297
            SET_HIGH(gpr, value);
298
            return;
299
        case 12: /* Control */
300
            if (value & 1)
301
                fprintf(stderr, "smc91c111:EEPROM store not implemented\n");
302
            if (value & 2)
303
                fprintf(stderr, "smc91c111:EEPROM reload not implemented\n");
304
            value &= ~3;
305
            SET_LOW(ctr, value);
306
            return;
307
        case 13:
308
            SET_HIGH(ctr, value);
309
            return;
310
        }
311
        break;
312

    
313
    case 2:
314
        switch (offset) {
315
        case 0: /* MMU Command */
316
            switch (value >> 5) {
317
            case 0: /* no-op */
318
                break;
319
            case 1: /* Allocate for TX.  */
320
                s->tx_alloc = 0x80;
321
                s->int_level &= ~INT_ALLOC;
322
                smc91c111_update(s);
323
                smc91c111_tx_alloc(s);
324
                break;
325
            case 2: /* Reset MMU.  */
326
                s->allocated = 0;
327
                s->tx_fifo_len = 0;
328
                s->tx_fifo_done_len = 0;
329
                s->rx_fifo_len = 0;
330
                s->tx_alloc = 0;
331
                break;
332
            case 3: /* Remove from RX FIFO.  */
333
                smc91c111_pop_rx_fifo(s);
334
                break;
335
            case 4: /* Remove from RX FIFO and release.  */
336
                if (s->rx_fifo_len > 0) {
337
                    smc91c111_release_packet(s, s->rx_fifo[0]);
338
                }
339
                smc91c111_pop_rx_fifo(s);
340
                break;
341
            case 5: /* Release.  */
342
                smc91c111_release_packet(s, s->packet_num);
343
                break;
344
            case 6: /* Add to TX FIFO.  */
345
                smc91c111_queue_tx(s, s->packet_num);
346
                break;
347
            case 7: /* Reset TX FIFO.  */
348
                s->tx_fifo_len = 0;
349
                s->tx_fifo_done_len = 0;
350
                break;
351
            }
352
            return;
353
        case 1:
354
            /* Ignore.  */
355
            return;
356
        case 2: /* Packet Number Register */
357
            s->packet_num = value;
358
            return;
359
        case 3: case 4: case 5:
360
            /* Should be readonly, but linux writes to them anyway. Ignore.  */
361
            return;
362
        case 6: /* Pointer */
363
            SET_LOW(ptr, value);
364
            return;
365
        case 7:
366
            SET_HIGH(ptr, value);
367
            return;
368
        case 8: case 9: case 10: case 11: /* Data */
369
            {
370
                int p;
371
                int n;
372

    
373
                if (s->ptr & 0x8000)
374
                    n = s->rx_fifo[0];
375
                else
376
                    n = s->packet_num;
377
                p = s->ptr & 0x07ff;
378
                if (s->ptr & 0x4000) {
379
                    s->ptr = (s->ptr & 0xf800) | ((s->ptr + 1) & 0x7ff);
380
                } else {
381
                    p += (offset & 3);
382
                }
383
                s->data[n][p] = value;
384
            }
385
            return;
386
        case 12: /* Interrupt ACK.  */
387
            s->int_level &= ~(value & 0xd6);
388
            if (value & INT_TX)
389
                smc91c111_pop_tx_fifo_done(s);
390
            smc91c111_update(s);
391
            return;
392
        case 13: /* Interrupt mask.  */
393
            s->int_mask = value;
394
            smc91c111_update(s);
395
            return;
396
        }
397
        break;;
398

    
399
    case 3:
400
        switch (offset) {
401
        case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7:
402
            /* Multicast table.  */
403
            /* Not implemented.  */
404
            return;
405
        case 8: case 9: /* Management Interface.  */
406
            /* Not implemented.  */
407
            return;
408
        case 12: /* Early receive.  */
409
            s->ercv = value & 0x1f;
410
        case 13:
411
            /* Ignore.  */
412
            return;
413
        }
414
        break;
415
    }
416
    cpu_abort (cpu_single_env, "smc91c111_write: Bad reg %d:%x\n",
417
               s->bank, offset);
418
}
419

    
420
static uint32_t smc91c111_readb(void *opaque, target_phys_addr_t offset)
421
{
422
    smc91c111_state *s = (smc91c111_state *)opaque;
423

    
424
    offset -= s->base;
425
    if (offset == 14) {
426
        return s->bank;
427
    }
428
    if (offset == 15)
429
        return 0x33;
430
    switch (s->bank) {
431
    case 0:
432
        switch (offset) {
433
        case 0: /* TCR */
434
            return s->tcr & 0xff;
435
        case 1:
436
            return s->tcr >> 8;
437
        case 2: /* EPH Status */
438
            return 0;
439
        case 3:
440
            return 0x40;
441
        case 4: /* RCR */
442
            return s->rcr & 0xff;
443
        case 5:
444
            return s->rcr >> 8;
445
        case 6: /* Counter */
446
        case 7:
447
            /* Not implemented.  */
448
            return 0;
449
        case 8: /* Memory size.  */
450
            return NUM_PACKETS;
451
        case 9: /* Free memory available.  */
452
            {
453
                int i;
454
                int n;
455
                n = 0;
456
                for (i = 0; i < NUM_PACKETS; i++) {
457
                    if (s->allocated & (1 << i))
458
                        n++;
459
                }
460
                return n;
461
            }
462
        case 10: case 11: /* RPCR */
463
            /* Not implemented.  */
464
            return 0;
465
        }
466
        break;
467

    
468
    case 1:
469
        switch (offset) {
470
        case 0: /* CONFIG */
471
            return s->cr & 0xff;
472
        case 1:
473
            return s->cr >> 8;
474
        case 2: case 3: /* BASE */
475
            /* Not implemented.  */
476
            return 0;
477
        case 4: case 5: case 6: case 7: case 8: case 9: /* IA */
478
            return s->macaddr[offset - 4];
479
        case 10: /* General Purpose */
480
            return s->gpr & 0xff;
481
        case 11:
482
            return s->gpr >> 8;
483
        case 12: /* Control */
484
            return s->ctr & 0xff;
485
        case 13:
486
            return s->ctr >> 8;
487
        }
488
        break;
489

    
490
    case 2:
491
        switch (offset) {
492
        case 0: case 1: /* MMUCR Busy bit.  */
493
            return 0;
494
        case 2: /* Packet Number.  */
495
            return s->packet_num;
496
        case 3: /* Allocation Result.  */
497
            return s->tx_alloc;
498
        case 4: /* TX FIFO */
499
            if (s->tx_fifo_done_len == 0)
500
                return 0x80;
501
            else
502
                return s->tx_fifo_done[0];
503
        case 5: /* RX FIFO */
504
            if (s->rx_fifo_len == 0)
505
                return 0x80;
506
            else
507
                return s->rx_fifo[0];
508
        case 6: /* Pointer */
509
            return s->ptr & 0xff;
510
        case 7:
511
            return (s->ptr >> 8) & 0xf7;
512
        case 8: case 9: case 10: case 11: /* Data */
513
            {
514
                int p;
515
                int n;
516

    
517
                if (s->ptr & 0x8000)
518
                    n = s->rx_fifo[0];
519
                else
520
                    n = s->packet_num;
521
                p = s->ptr & 0x07ff;
522
                if (s->ptr & 0x4000) {
523
                    s->ptr = (s->ptr & 0xf800) | ((s->ptr + 1) & 0x07ff);
524
                } else {
525
                    p += (offset & 3);
526
                }
527
                return s->data[n][p];
528
            }
529
        case 12: /* Interrupt status.  */
530
            return s->int_level;
531
        case 13: /* Interrupt mask.  */
532
            return s->int_mask;
533
        }
534
        break;
535

    
536
    case 3:
537
        switch (offset) {
538
        case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7:
539
            /* Multicast table.  */
540
            /* Not implemented.  */
541
            return 0;
542
        case 8: /* Management Interface.  */
543
            /* Not implemented.  */
544
            return 0x30;
545
        case 9:
546
            return 0x33;
547
        case 10: /* Revision.  */
548
            return 0x91;
549
        case 11:
550
            return 0x33;
551
        case 12:
552
            return s->ercv;
553
        case 13:
554
            return 0;
555
        }
556
        break;
557
    }
558
    cpu_abort (cpu_single_env, "smc91c111_read: Bad reg %d:%x\n",
559
               s->bank, offset);
560
    return 0;
561
}
562

    
563
static void smc91c111_writew(void *opaque, target_phys_addr_t offset,
564
                             uint32_t value)
565
{
566
    smc91c111_writeb(opaque, offset, value & 0xff);
567
    smc91c111_writeb(opaque, offset + 1, value >> 8);
568
}
569

    
570
static void smc91c111_writel(void *opaque, target_phys_addr_t offset,
571
                             uint32_t value)
572
{
573
    smc91c111_state *s = (smc91c111_state *)opaque;
574
    /* 32-bit writes to offset 0xc only actually write to the bank select
575
       register (offset 0xe)  */
576
    if (offset != s->base + 0xc)
577
        smc91c111_writew(opaque, offset, value & 0xffff);
578
    smc91c111_writew(opaque, offset + 2, value >> 16);
579
}
580

    
581
static uint32_t smc91c111_readw(void *opaque, target_phys_addr_t offset)
582
{
583
    uint32_t val;
584
    val = smc91c111_readb(opaque, offset);
585
    val |= smc91c111_readb(opaque, offset + 1) << 8;
586
    return val;
587
}
588

    
589
static uint32_t smc91c111_readl(void *opaque, target_phys_addr_t offset)
590
{
591
    uint32_t val;
592
    val = smc91c111_readw(opaque, offset);
593
    val |= smc91c111_readw(opaque, offset + 2) << 16;
594
    return val;
595
}
596

    
597
static int smc91c111_can_receive(void *opaque)
598
{
599
    smc91c111_state *s = (smc91c111_state *)opaque;
600

    
601
    if ((s->rcr & RCR_RXEN) == 0 || (s->rcr & RCR_SOFT_RST))
602
        return 1;
603
    if (s->allocated == (1 << NUM_PACKETS) - 1)
604
        return 0;
605
    return 1;
606
}
607

    
608
static void smc91c111_receive(void *opaque, const uint8_t *buf, int size)
609
{
610
    smc91c111_state *s = (smc91c111_state *)opaque;
611
    int status;
612
    int packetsize;
613
    uint32_t crc;
614
    int packetnum;
615
    uint8_t *p;
616

    
617
    if ((s->rcr & RCR_RXEN) == 0 || (s->rcr & RCR_SOFT_RST))
618
        return;
619
    /* Short packets are padded with zeros.  Receiving a packet
620
       < 64 bytes long is considered an error condition.  */
621
    if (size < 64)
622
        packetsize = 64;
623
    else
624
        packetsize = (size & ~1);
625
    packetsize += 6;
626
    crc = (s->rcr & RCR_STRIP_CRC) == 0;
627
    if (crc)
628
        packetsize += 4;
629
    /* TODO: Flag overrun and receive errors.  */
630
    if (packetsize > 2048)
631
        return;
632
    packetnum = smc91c111_allocate_packet(s);
633
    if (packetnum == 0x80)
634
        return;
635
    s->rx_fifo[s->rx_fifo_len++] = packetnum;
636

    
637
    p = &s->data[packetnum][0];
638
    /* ??? Multicast packets?  */
639
    status = 0;
640
    if (size > 1518)
641
        status |= RS_TOOLONG;
642
    if (size & 1)
643
        status |= RS_ODDFRAME;
644
    *(p++) = status & 0xff;
645
    *(p++) = status >> 8;
646
    *(p++) = packetsize & 0xff;
647
    *(p++) = packetsize >> 8;
648
    memcpy(p, buf, size & ~1);
649
    p += (size & ~1);
650
    /* Pad short packets.  */
651
    if (size < 64) {
652
        int pad;
653
        
654
        if (size & 1)
655
            *(p++) = buf[size - 1];
656
        pad = 64 - size;
657
        memset(p, 0, pad);
658
        p += pad;
659
        size = 64;
660
    }
661
    /* It's not clear if the CRC should go before or after the last byte in
662
       odd sized packets.  Linux disables the CRC, so that's no help.
663
       The pictures in the documentation show the CRC aligned on a 16-bit
664
       boundary before the last odd byte, so that's what we do.  */
665
    if (crc) {
666
        crc = crc32(~0, buf, size);
667
        *(p++) = crc & 0xff; crc >>= 8;
668
        *(p++) = crc & 0xff; crc >>= 8;
669
        *(p++) = crc & 0xff; crc >>= 8;
670
        *(p++) = crc & 0xff; crc >>= 8;
671
    }
672
    if (size & 1) {
673
        *(p++) = buf[size - 1];
674
        *(p++) = 0x60;
675
    } else {
676
        *(p++) = 0;
677
        *(p++) = 0x40;
678
    }
679
    /* TODO: Raise early RX interrupt?  */
680
    s->int_level |= INT_RCV;
681
    smc91c111_update(s);
682
}
683

    
684
static CPUReadMemoryFunc *smc91c111_readfn[] = {
685
    smc91c111_readb,
686
    smc91c111_readw,
687
    smc91c111_readl
688
};
689

    
690
static CPUWriteMemoryFunc *smc91c111_writefn[] = {
691
    smc91c111_writeb,
692
    smc91c111_writew,
693
    smc91c111_writel
694
};
695

    
696
void smc91c111_init(NICInfo *nd, uint32_t base, void *pic, int irq)
697
{
698
    smc91c111_state *s;
699
    int iomemtype;
700

    
701
    s = (smc91c111_state *)qemu_mallocz(sizeof(smc91c111_state));
702
    iomemtype = cpu_register_io_memory(0, smc91c111_readfn,
703
                                       smc91c111_writefn, s);
704
    cpu_register_physical_memory(base, 16, iomemtype);
705
    s->base = base;
706
    s->pic = pic;
707
    s->irq = irq;
708
    memcpy(s->macaddr, nd->macaddr, 6);
709

    
710
    smc91c111_reset(s);
711

    
712
    s->vc = qemu_new_vlan_client(nd->vlan, smc91c111_receive,
713
                                 smc91c111_can_receive, s);
714
    /* ??? Save/restore.  */
715
}