xref: /openbmc/qemu/hw/net/mcf_fec.c (revision 786f9ce20382704249883d7052f6869011d44281)
1 /*
2  * ColdFire Fast Ethernet Controller emulation.
3  *
4  * Copyright (c) 2007 CodeSourcery.
5  *
6  * This code is licensed under the GPL
7  */
8 #include "hw/hw.h"
9 #include "net/net.h"
10 #include "hw/m68k/mcf.h"
11 #include "hw/net/mii.h"
12 /* For crc32 */
13 #include <zlib.h>
14 #include "exec/address-spaces.h"
15 
16 //#define DEBUG_FEC 1
17 
18 #ifdef DEBUG_FEC
19 #define DPRINTF(fmt, ...) \
20 do { printf("mcf_fec: " fmt , ## __VA_ARGS__); } while (0)
21 #else
22 #define DPRINTF(fmt, ...) do {} while(0)
23 #endif
24 
25 #define FEC_MAX_FRAME_SIZE 2032
26 
27 typedef struct {
28     MemoryRegion *sysmem;
29     MemoryRegion iomem;
30     qemu_irq *irq;
31     NICState *nic;
32     NICConf conf;
33     uint32_t irq_state;
34     uint32_t eir;
35     uint32_t eimr;
36     int rx_enabled;
37     uint32_t rx_descriptor;
38     uint32_t tx_descriptor;
39     uint32_t ecr;
40     uint32_t mmfr;
41     uint32_t mscr;
42     uint32_t rcr;
43     uint32_t tcr;
44     uint32_t tfwr;
45     uint32_t rfsr;
46     uint32_t erdsr;
47     uint32_t etdsr;
48     uint32_t emrbr;
49 } mcf_fec_state;
50 
51 #define FEC_INT_HB   0x80000000
52 #define FEC_INT_BABR 0x40000000
53 #define FEC_INT_BABT 0x20000000
54 #define FEC_INT_GRA  0x10000000
55 #define FEC_INT_TXF  0x08000000
56 #define FEC_INT_TXB  0x04000000
57 #define FEC_INT_RXF  0x02000000
58 #define FEC_INT_RXB  0x01000000
59 #define FEC_INT_MII  0x00800000
60 #define FEC_INT_EB   0x00400000
61 #define FEC_INT_LC   0x00200000
62 #define FEC_INT_RL   0x00100000
63 #define FEC_INT_UN   0x00080000
64 
65 #define FEC_EN      2
66 #define FEC_RESET   1
67 
68 /* Map interrupt flags onto IRQ lines.  */
69 #define FEC_NUM_IRQ 13
70 static const uint32_t mcf_fec_irq_map[FEC_NUM_IRQ] = {
71     FEC_INT_TXF,
72     FEC_INT_TXB,
73     FEC_INT_UN,
74     FEC_INT_RL,
75     FEC_INT_RXF,
76     FEC_INT_RXB,
77     FEC_INT_MII,
78     FEC_INT_LC,
79     FEC_INT_HB,
80     FEC_INT_GRA,
81     FEC_INT_EB,
82     FEC_INT_BABT,
83     FEC_INT_BABR
84 };
85 
86 /* Buffer Descriptor.  */
87 typedef struct {
88     uint16_t flags;
89     uint16_t length;
90     uint32_t data;
91 } mcf_fec_bd;
92 
93 #define FEC_BD_R    0x8000
94 #define FEC_BD_E    0x8000
95 #define FEC_BD_O1   0x4000
96 #define FEC_BD_W    0x2000
97 #define FEC_BD_O2   0x1000
98 #define FEC_BD_L    0x0800
99 #define FEC_BD_TC   0x0400
100 #define FEC_BD_ABC  0x0200
101 #define FEC_BD_M    0x0100
102 #define FEC_BD_BC   0x0080
103 #define FEC_BD_MC   0x0040
104 #define FEC_BD_LG   0x0020
105 #define FEC_BD_NO   0x0010
106 #define FEC_BD_CR   0x0004
107 #define FEC_BD_OV   0x0002
108 #define FEC_BD_TR   0x0001
109 
110 static void mcf_fec_read_bd(mcf_fec_bd *bd, uint32_t addr)
111 {
112     cpu_physical_memory_read(addr, bd, sizeof(*bd));
113     be16_to_cpus(&bd->flags);
114     be16_to_cpus(&bd->length);
115     be32_to_cpus(&bd->data);
116 }
117 
118 static void mcf_fec_write_bd(mcf_fec_bd *bd, uint32_t addr)
119 {
120     mcf_fec_bd tmp;
121     tmp.flags = cpu_to_be16(bd->flags);
122     tmp.length = cpu_to_be16(bd->length);
123     tmp.data = cpu_to_be32(bd->data);
124     cpu_physical_memory_write(addr, &tmp, sizeof(tmp));
125 }
126 
127 static void mcf_fec_update(mcf_fec_state *s)
128 {
129     uint32_t active;
130     uint32_t changed;
131     uint32_t mask;
132     int i;
133 
134     active = s->eir & s->eimr;
135     changed = active ^s->irq_state;
136     for (i = 0; i < FEC_NUM_IRQ; i++) {
137         mask = mcf_fec_irq_map[i];
138         if (changed & mask) {
139             DPRINTF("IRQ %d = %d\n", i, (active & mask) != 0);
140             qemu_set_irq(s->irq[i], (active & mask) != 0);
141         }
142     }
143     s->irq_state = active;
144 }
145 
146 static void mcf_fec_do_tx(mcf_fec_state *s)
147 {
148     uint32_t addr;
149     mcf_fec_bd bd;
150     int frame_size;
151     int len;
152     uint8_t frame[FEC_MAX_FRAME_SIZE];
153     uint8_t *ptr;
154 
155     DPRINTF("do_tx\n");
156     ptr = frame;
157     frame_size = 0;
158     addr = s->tx_descriptor;
159     while (1) {
160         mcf_fec_read_bd(&bd, addr);
161         DPRINTF("tx_bd %x flags %04x len %d data %08x\n",
162                 addr, bd.flags, bd.length, bd.data);
163         if ((bd.flags & FEC_BD_R) == 0) {
164             /* Run out of descriptors to transmit.  */
165             break;
166         }
167         len = bd.length;
168         if (frame_size + len > FEC_MAX_FRAME_SIZE) {
169             len = FEC_MAX_FRAME_SIZE - frame_size;
170             s->eir |= FEC_INT_BABT;
171         }
172         cpu_physical_memory_read(bd.data, ptr, len);
173         ptr += len;
174         frame_size += len;
175         if (bd.flags & FEC_BD_L) {
176             /* Last buffer in frame.  */
177             DPRINTF("Sending packet\n");
178             qemu_send_packet(qemu_get_queue(s->nic), frame, len);
179             ptr = frame;
180             frame_size = 0;
181             s->eir |= FEC_INT_TXF;
182         }
183         s->eir |= FEC_INT_TXB;
184         bd.flags &= ~FEC_BD_R;
185         /* Write back the modified descriptor.  */
186         mcf_fec_write_bd(&bd, addr);
187         /* Advance to the next descriptor.  */
188         if ((bd.flags & FEC_BD_W) != 0) {
189             addr = s->etdsr;
190         } else {
191             addr += 8;
192         }
193     }
194     s->tx_descriptor = addr;
195 }
196 
197 static void mcf_fec_enable_rx(mcf_fec_state *s)
198 {
199     mcf_fec_bd bd;
200 
201     mcf_fec_read_bd(&bd, s->rx_descriptor);
202     s->rx_enabled = ((bd.flags & FEC_BD_E) != 0);
203     if (!s->rx_enabled)
204         DPRINTF("RX buffer full\n");
205 }
206 
207 static void mcf_fec_reset(mcf_fec_state *s)
208 {
209     s->eir = 0;
210     s->eimr = 0;
211     s->rx_enabled = 0;
212     s->ecr = 0;
213     s->mscr = 0;
214     s->rcr = 0x05ee0001;
215     s->tcr = 0;
216     s->tfwr = 0;
217     s->rfsr = 0x500;
218 }
219 
220 #define MMFR_WRITE_OP	(1 << 28)
221 #define MMFR_READ_OP	(2 << 28)
222 #define MMFR_PHYADDR(v)	(((v) >> 23) & 0x1f)
223 #define MMFR_REGNUM(v)	(((v) >> 18) & 0x1f)
224 
225 static uint64_t mcf_fec_read_mdio(mcf_fec_state *s)
226 {
227     uint64_t v;
228 
229     if (s->mmfr & MMFR_WRITE_OP)
230         return s->mmfr;
231     if (MMFR_PHYADDR(s->mmfr) != 1)
232         return s->mmfr |= 0xffff;
233 
234     switch (MMFR_REGNUM(s->mmfr)) {
235     case MII_BMCR:
236         v = MII_BMCR_SPEED | MII_BMCR_AUTOEN | MII_BMCR_FD;
237         break;
238     case MII_BMSR:
239         v = MII_BMSR_100TX_FD | MII_BMSR_100TX_HD | MII_BMSR_10T_FD |
240             MII_BMSR_10T_HD | MII_BMSR_MFPS | MII_BMSR_AN_COMP |
241             MII_BMSR_AUTONEG | MII_BMSR_LINK_ST;
242         break;
243     case MII_PHYID1:
244         v = DP83848_PHYID1;
245         break;
246     case MII_PHYID2:
247         v = DP83848_PHYID2;
248         break;
249     case MII_ANAR:
250         v = MII_ANAR_TXFD | MII_ANAR_TX | MII_ANAR_10FD |
251             MII_ANAR_10 | MII_ANAR_CSMACD;
252         break;
253     case MII_ANLPAR:
254         v = MII_ANLPAR_ACK | MII_ANLPAR_TXFD | MII_ANLPAR_TX |
255             MII_ANLPAR_10FD | MII_ANLPAR_10 | MII_ANLPAR_CSMACD;
256         break;
257     default:
258         v = 0xffff;
259         break;
260     }
261     s->mmfr = (s->mmfr & ~0xffff) | v;
262     return s->mmfr;
263 }
264 
265 static uint64_t mcf_fec_read(void *opaque, hwaddr addr,
266                              unsigned size)
267 {
268     mcf_fec_state *s = (mcf_fec_state *)opaque;
269     switch (addr & 0x3ff) {
270     case 0x004: return s->eir;
271     case 0x008: return s->eimr;
272     case 0x010: return s->rx_enabled ? (1 << 24) : 0; /* RDAR */
273     case 0x014: return 0; /* TDAR */
274     case 0x024: return s->ecr;
275     case 0x040: return mcf_fec_read_mdio(s);
276     case 0x044: return s->mscr;
277     case 0x064: return 0; /* MIBC */
278     case 0x084: return s->rcr;
279     case 0x0c4: return s->tcr;
280     case 0x0e4: /* PALR */
281         return (s->conf.macaddr.a[0] << 24) | (s->conf.macaddr.a[1] << 16)
282               | (s->conf.macaddr.a[2] << 8) | s->conf.macaddr.a[3];
283         break;
284     case 0x0e8: /* PAUR */
285         return (s->conf.macaddr.a[4] << 24) | (s->conf.macaddr.a[5] << 16) | 0x8808;
286     case 0x0ec: return 0x10000; /* OPD */
287     case 0x118: return 0;
288     case 0x11c: return 0;
289     case 0x120: return 0;
290     case 0x124: return 0;
291     case 0x144: return s->tfwr;
292     case 0x14c: return 0x600;
293     case 0x150: return s->rfsr;
294     case 0x180: return s->erdsr;
295     case 0x184: return s->etdsr;
296     case 0x188: return s->emrbr;
297     default:
298         hw_error("mcf_fec_read: Bad address 0x%x\n", (int)addr);
299         return 0;
300     }
301 }
302 
303 static void mcf_fec_write(void *opaque, hwaddr addr,
304                           uint64_t value, unsigned size)
305 {
306     mcf_fec_state *s = (mcf_fec_state *)opaque;
307     switch (addr & 0x3ff) {
308     case 0x004:
309         s->eir &= ~value;
310         break;
311     case 0x008:
312         s->eimr = value;
313         break;
314     case 0x010: /* RDAR */
315         if ((s->ecr & FEC_EN) && !s->rx_enabled) {
316             DPRINTF("RX enable\n");
317             mcf_fec_enable_rx(s);
318         }
319         break;
320     case 0x014: /* TDAR */
321         if (s->ecr & FEC_EN) {
322             mcf_fec_do_tx(s);
323         }
324         break;
325     case 0x024:
326         s->ecr = value;
327         if (value & FEC_RESET) {
328             DPRINTF("Reset\n");
329             mcf_fec_reset(s);
330         }
331         if ((s->ecr & FEC_EN) == 0) {
332             s->rx_enabled = 0;
333         }
334         break;
335     case 0x040:
336         s->mmfr = value;
337         s->eir |= FEC_INT_MII;
338         break;
339     case 0x044:
340         s->mscr = value & 0xfe;
341         break;
342     case 0x064:
343         /* TODO: Implement MIB.  */
344         break;
345     case 0x084:
346         s->rcr = value & 0x07ff003f;
347         /* TODO: Implement LOOP mode.  */
348         break;
349     case 0x0c4: /* TCR */
350         /* We transmit immediately, so raise GRA immediately.  */
351         s->tcr = value;
352         if (value & 1)
353             s->eir |= FEC_INT_GRA;
354         break;
355     case 0x0e4: /* PALR */
356         s->conf.macaddr.a[0] = value >> 24;
357         s->conf.macaddr.a[1] = value >> 16;
358         s->conf.macaddr.a[2] = value >> 8;
359         s->conf.macaddr.a[3] = value;
360         break;
361     case 0x0e8: /* PAUR */
362         s->conf.macaddr.a[4] = value >> 24;
363         s->conf.macaddr.a[5] = value >> 16;
364         break;
365     case 0x0ec:
366         /* OPD */
367         break;
368     case 0x118:
369     case 0x11c:
370     case 0x120:
371     case 0x124:
372         /* TODO: implement MAC hash filtering.  */
373         break;
374     case 0x144:
375         s->tfwr = value & 3;
376         break;
377     case 0x14c:
378         /* FRBR writes ignored.  */
379         break;
380     case 0x150:
381         s->rfsr = (value & 0x3fc) | 0x400;
382         break;
383     case 0x180:
384         s->erdsr = value & ~3;
385         s->rx_descriptor = s->erdsr;
386         break;
387     case 0x184:
388         s->etdsr = value & ~3;
389         s->tx_descriptor = s->etdsr;
390         break;
391     case 0x188:
392         s->emrbr = value & 0x7f0;
393         break;
394     default:
395         hw_error("mcf_fec_write Bad address 0x%x\n", (int)addr);
396     }
397     mcf_fec_update(s);
398 }
399 
400 static ssize_t mcf_fec_receive(NetClientState *nc, const uint8_t *buf, size_t size)
401 {
402     mcf_fec_state *s = qemu_get_nic_opaque(nc);
403     mcf_fec_bd bd;
404     uint32_t flags = 0;
405     uint32_t addr;
406     uint32_t crc;
407     uint32_t buf_addr;
408     uint8_t *crc_ptr;
409     unsigned int buf_len;
410     size_t retsize;
411 
412     DPRINTF("do_rx len %d\n", size);
413     if (!s->rx_enabled) {
414         return -1;
415     }
416     /* 4 bytes for the CRC.  */
417     size += 4;
418     crc = cpu_to_be32(crc32(~0, buf, size));
419     crc_ptr = (uint8_t *)&crc;
420     /* Huge frames are truncted.  */
421     if (size > FEC_MAX_FRAME_SIZE) {
422         size = FEC_MAX_FRAME_SIZE;
423         flags |= FEC_BD_TR | FEC_BD_LG;
424     }
425     /* Frames larger than the user limit just set error flags.  */
426     if (size > (s->rcr >> 16)) {
427         flags |= FEC_BD_LG;
428     }
429     addr = s->rx_descriptor;
430     retsize = size;
431     while (size > 0) {
432         mcf_fec_read_bd(&bd, addr);
433         if ((bd.flags & FEC_BD_E) == 0) {
434             /* No descriptors available.  Bail out.  */
435             /* FIXME: This is wrong.  We should probably either save the
436                remainder for when more RX buffers are available, or
437                flag an error.  */
438             fprintf(stderr, "mcf_fec: Lost end of frame\n");
439             break;
440         }
441         buf_len = (size <= s->emrbr) ? size: s->emrbr;
442         bd.length = buf_len;
443         size -= buf_len;
444         DPRINTF("rx_bd %x length %d\n", addr, bd.length);
445         /* The last 4 bytes are the CRC.  */
446         if (size < 4)
447             buf_len += size - 4;
448         buf_addr = bd.data;
449         cpu_physical_memory_write(buf_addr, buf, buf_len);
450         buf += buf_len;
451         if (size < 4) {
452             cpu_physical_memory_write(buf_addr + buf_len, crc_ptr, 4 - size);
453             crc_ptr += 4 - size;
454         }
455         bd.flags &= ~FEC_BD_E;
456         if (size == 0) {
457             /* Last buffer in frame.  */
458             bd.flags |= flags | FEC_BD_L;
459             DPRINTF("rx frame flags %04x\n", bd.flags);
460             s->eir |= FEC_INT_RXF;
461         } else {
462             s->eir |= FEC_INT_RXB;
463         }
464         mcf_fec_write_bd(&bd, addr);
465         /* Advance to the next descriptor.  */
466         if ((bd.flags & FEC_BD_W) != 0) {
467             addr = s->erdsr;
468         } else {
469             addr += 8;
470         }
471     }
472     s->rx_descriptor = addr;
473     mcf_fec_enable_rx(s);
474     mcf_fec_update(s);
475     return retsize;
476 }
477 
478 static const MemoryRegionOps mcf_fec_ops = {
479     .read = mcf_fec_read,
480     .write = mcf_fec_write,
481     .endianness = DEVICE_NATIVE_ENDIAN,
482 };
483 
484 static NetClientInfo net_mcf_fec_info = {
485     .type = NET_CLIENT_OPTIONS_KIND_NIC,
486     .size = sizeof(NICState),
487     .receive = mcf_fec_receive,
488 };
489 
490 void mcf_fec_init(MemoryRegion *sysmem, NICInfo *nd,
491                   hwaddr base, qemu_irq *irq)
492 {
493     mcf_fec_state *s;
494 
495     qemu_check_nic_model(nd, "mcf_fec");
496 
497     s = (mcf_fec_state *)g_malloc0(sizeof(mcf_fec_state));
498     s->sysmem = sysmem;
499     s->irq = irq;
500 
501     memory_region_init_io(&s->iomem, NULL, &mcf_fec_ops, s, "fec", 0x400);
502     memory_region_add_subregion(sysmem, base, &s->iomem);
503 
504     s->conf.macaddr = nd->macaddr;
505     s->conf.peers.ncs[0] = nd->netdev;
506 
507     s->nic = qemu_new_nic(&net_mcf_fec_info, &s->conf, nd->model, nd->name, s);
508 
509     qemu_format_nic_info_str(qemu_get_queue(s->nic), s->conf.macaddr.a);
510 }
511