xref: /openbmc/qemu/hw/net/etraxfs_eth.c (revision 6775e2c4)
1 /*
2  * QEMU ETRAX Ethernet Controller.
3  *
4  * Copyright (c) 2008 Edgar E. Iglesias, Axis Communications AB.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 #include <stdio.h>
26 #include "hw/sysbus.h"
27 #include "net/net.h"
28 #include "hw/cris/etraxfs.h"
29 
30 #define D(x)
31 
32 /* Advertisement control register. */
33 #define ADVERTISE_10HALF        0x0020  /* Try for 10mbps half-duplex  */
34 #define ADVERTISE_10FULL        0x0040  /* Try for 10mbps full-duplex  */
35 #define ADVERTISE_100HALF       0x0080  /* Try for 100mbps half-duplex */
36 #define ADVERTISE_100FULL       0x0100  /* Try for 100mbps full-duplex */
37 
38 /*
39  * The MDIO extensions in the TDK PHY model were reversed engineered from the
40  * linux driver (PHYID and Diagnostics reg).
41  * TODO: Add friendly names for the register nums.
42  */
43 struct qemu_phy
44 {
45     uint32_t regs[32];
46 
47     int link;
48 
49     unsigned int (*read)(struct qemu_phy *phy, unsigned int req);
50     void (*write)(struct qemu_phy *phy, unsigned int req, unsigned int data);
51 };
52 
53 static unsigned int tdk_read(struct qemu_phy *phy, unsigned int req)
54 {
55     int regnum;
56     unsigned r = 0;
57 
58     regnum = req & 0x1f;
59 
60     switch (regnum) {
61     case 1:
62         if (!phy->link) {
63             break;
64         }
65         /* MR1.     */
66         /* Speeds and modes.  */
67         r |= (1 << 13) | (1 << 14);
68         r |= (1 << 11) | (1 << 12);
69         r |= (1 << 5); /* Autoneg complete.  */
70         r |= (1 << 3); /* Autoneg able.     */
71         r |= (1 << 2); /* link.     */
72         break;
73     case 5:
74         /* Link partner ability.
75            We are kind; always agree with whatever best mode
76            the guest advertises.  */
77         r = 1 << 14; /* Success.  */
78         /* Copy advertised modes.  */
79         r |= phy->regs[4] & (15 << 5);
80         /* Autoneg support.  */
81         r |= 1;
82         break;
83     case 18:
84     {
85         /* Diagnostics reg.  */
86         int duplex = 0;
87         int speed_100 = 0;
88 
89         if (!phy->link) {
90             break;
91         }
92 
93         /* Are we advertising 100 half or 100 duplex ? */
94         speed_100 = !!(phy->regs[4] & ADVERTISE_100HALF);
95         speed_100 |= !!(phy->regs[4] & ADVERTISE_100FULL);
96 
97         /* Are we advertising 10 duplex or 100 duplex ? */
98         duplex = !!(phy->regs[4] & ADVERTISE_100FULL);
99         duplex |= !!(phy->regs[4] & ADVERTISE_10FULL);
100         r = (speed_100 << 10) | (duplex << 11);
101     }
102     break;
103 
104     default:
105         r = phy->regs[regnum];
106         break;
107     }
108     D(printf("\n%s %x = reg[%d]\n", __func__, r, regnum));
109     return r;
110 }
111 
112 static void
113 tdk_write(struct qemu_phy *phy, unsigned int req, unsigned int data)
114 {
115     int regnum;
116 
117     regnum = req & 0x1f;
118     D(printf("%s reg[%d] = %x\n", __func__, regnum, data));
119     switch (regnum) {
120     default:
121         phy->regs[regnum] = data;
122         break;
123     }
124 }
125 
126 static void
127 tdk_init(struct qemu_phy *phy)
128 {
129     phy->regs[0] = 0x3100;
130     /* PHY Id.  */
131     phy->regs[2] = 0x0300;
132     phy->regs[3] = 0xe400;
133     /* Autonegotiation advertisement reg.  */
134     phy->regs[4] = 0x01E1;
135     phy->link = 1;
136 
137     phy->read = tdk_read;
138     phy->write = tdk_write;
139 }
140 
141 struct qemu_mdio
142 {
143     /* bus.     */
144     int mdc;
145     int mdio;
146 
147     /* decoder.  */
148     enum {
149         PREAMBLE,
150         SOF,
151         OPC,
152         ADDR,
153         REQ,
154         TURNAROUND,
155         DATA
156     } state;
157     unsigned int drive;
158 
159     unsigned int cnt;
160     unsigned int addr;
161     unsigned int opc;
162     unsigned int req;
163     unsigned int data;
164 
165     struct qemu_phy *devs[32];
166 };
167 
168 static void
169 mdio_attach(struct qemu_mdio *bus, struct qemu_phy *phy, unsigned int addr)
170 {
171     bus->devs[addr & 0x1f] = phy;
172 }
173 
174 #ifdef USE_THIS_DEAD_CODE
175 static void
176 mdio_detach(struct qemu_mdio *bus, struct qemu_phy *phy, unsigned int addr)
177 {
178     bus->devs[addr & 0x1f] = NULL;
179 }
180 #endif
181 
182 static void mdio_read_req(struct qemu_mdio *bus)
183 {
184     struct qemu_phy *phy;
185 
186     phy = bus->devs[bus->addr];
187     if (phy && phy->read) {
188         bus->data = phy->read(phy, bus->req);
189     } else {
190         bus->data = 0xffff;
191     }
192 }
193 
194 static void mdio_write_req(struct qemu_mdio *bus)
195 {
196     struct qemu_phy *phy;
197 
198     phy = bus->devs[bus->addr];
199     if (phy && phy->write) {
200         phy->write(phy, bus->req, bus->data);
201     }
202 }
203 
204 static void mdio_cycle(struct qemu_mdio *bus)
205 {
206     bus->cnt++;
207 
208     D(printf("mdc=%d mdio=%d state=%d cnt=%d drv=%d\n",
209         bus->mdc, bus->mdio, bus->state, bus->cnt, bus->drive));
210 #if 0
211     if (bus->mdc) {
212         printf("%d", bus->mdio);
213     }
214 #endif
215     switch (bus->state) {
216     case PREAMBLE:
217         if (bus->mdc) {
218             if (bus->cnt >= (32 * 2) && !bus->mdio) {
219                 bus->cnt = 0;
220                 bus->state = SOF;
221                 bus->data = 0;
222             }
223         }
224         break;
225     case SOF:
226         if (bus->mdc) {
227             if (bus->mdio != 1) {
228                 printf("WARNING: no SOF\n");
229             }
230             if (bus->cnt == 1*2) {
231                 bus->cnt = 0;
232                 bus->opc = 0;
233                 bus->state = OPC;
234             }
235         }
236         break;
237     case OPC:
238         if (bus->mdc) {
239             bus->opc <<= 1;
240             bus->opc |= bus->mdio & 1;
241             if (bus->cnt == 2*2) {
242                 bus->cnt = 0;
243                 bus->addr = 0;
244                 bus->state = ADDR;
245             }
246         }
247         break;
248     case ADDR:
249         if (bus->mdc) {
250             bus->addr <<= 1;
251             bus->addr |= bus->mdio & 1;
252 
253             if (bus->cnt == 5*2) {
254                 bus->cnt = 0;
255                 bus->req = 0;
256                 bus->state = REQ;
257             }
258         }
259         break;
260     case REQ:
261         if (bus->mdc) {
262             bus->req <<= 1;
263             bus->req |= bus->mdio & 1;
264             if (bus->cnt == 5*2) {
265                 bus->cnt = 0;
266                 bus->state = TURNAROUND;
267             }
268         }
269         break;
270     case TURNAROUND:
271         if (bus->mdc && bus->cnt == 2*2) {
272             bus->mdio = 0;
273             bus->cnt = 0;
274 
275             if (bus->opc == 2) {
276                 bus->drive = 1;
277                 mdio_read_req(bus);
278                 bus->mdio = bus->data & 1;
279             }
280             bus->state = DATA;
281         }
282         break;
283     case DATA:
284         if (!bus->mdc) {
285             if (bus->drive) {
286                 bus->mdio = !!(bus->data & (1 << 15));
287                 bus->data <<= 1;
288             }
289         } else {
290             if (!bus->drive) {
291                 bus->data <<= 1;
292                 bus->data |= bus->mdio;
293             }
294             if (bus->cnt == 16 * 2) {
295                 bus->cnt = 0;
296                 bus->state = PREAMBLE;
297                 if (!bus->drive) {
298                     mdio_write_req(bus);
299                 }
300                 bus->drive = 0;
301             }
302         }
303         break;
304     default:
305         break;
306     }
307 }
308 
309 /* ETRAX-FS Ethernet MAC block starts here.  */
310 
311 #define RW_MA0_LO      0x00
312 #define RW_MA0_HI      0x01
313 #define RW_MA1_LO      0x02
314 #define RW_MA1_HI      0x03
315 #define RW_GA_LO      0x04
316 #define RW_GA_HI      0x05
317 #define RW_GEN_CTRL      0x06
318 #define RW_REC_CTRL      0x07
319 #define RW_TR_CTRL      0x08
320 #define RW_CLR_ERR      0x09
321 #define RW_MGM_CTRL      0x0a
322 #define R_STAT          0x0b
323 #define FS_ETH_MAX_REGS      0x17
324 
325 #define TYPE_ETRAX_FS_ETH "etraxfs-eth"
326 #define ETRAX_FS_ETH(obj) \
327     OBJECT_CHECK(ETRAXFSEthState, (obj), TYPE_ETRAX_FS_ETH)
328 
329 typedef struct ETRAXFSEthState
330 {
331     SysBusDevice parent_obj;
332 
333     MemoryRegion mmio;
334     NICState *nic;
335     NICConf conf;
336 
337     /* Two addrs in the filter.  */
338     uint8_t macaddr[2][6];
339     uint32_t regs[FS_ETH_MAX_REGS];
340 
341     union {
342         void *vdma_out;
343         struct etraxfs_dma_client *dma_out;
344     };
345     union {
346         void *vdma_in;
347         struct etraxfs_dma_client *dma_in;
348     };
349 
350     /* MDIO bus.  */
351     struct qemu_mdio mdio_bus;
352     unsigned int phyaddr;
353     int duplex_mismatch;
354 
355     /* PHY.     */
356     struct qemu_phy phy;
357 } ETRAXFSEthState;
358 
359 static void eth_validate_duplex(ETRAXFSEthState *eth)
360 {
361     struct qemu_phy *phy;
362     unsigned int phy_duplex;
363     unsigned int mac_duplex;
364     int new_mm = 0;
365 
366     phy = eth->mdio_bus.devs[eth->phyaddr];
367     phy_duplex = !!(phy->read(phy, 18) & (1 << 11));
368     mac_duplex = !!(eth->regs[RW_REC_CTRL] & 128);
369 
370     if (mac_duplex != phy_duplex) {
371         new_mm = 1;
372     }
373 
374     if (eth->regs[RW_GEN_CTRL] & 1) {
375         if (new_mm != eth->duplex_mismatch) {
376             if (new_mm) {
377                 printf("HW: WARNING ETH duplex mismatch MAC=%d PHY=%d\n",
378                        mac_duplex, phy_duplex);
379             } else {
380                 printf("HW: ETH duplex ok.\n");
381             }
382         }
383         eth->duplex_mismatch = new_mm;
384     }
385 }
386 
387 static uint64_t
388 eth_read(void *opaque, hwaddr addr, unsigned int size)
389 {
390     ETRAXFSEthState *eth = opaque;
391     uint32_t r = 0;
392 
393     addr >>= 2;
394 
395     switch (addr) {
396     case R_STAT:
397         r = eth->mdio_bus.mdio & 1;
398         break;
399     default:
400         r = eth->regs[addr];
401         D(printf("%s %x\n", __func__, addr * 4));
402         break;
403     }
404     return r;
405 }
406 
407 static void eth_update_ma(ETRAXFSEthState *eth, int ma)
408 {
409     int reg;
410     int i = 0;
411 
412     ma &= 1;
413 
414     reg = RW_MA0_LO;
415     if (ma) {
416         reg = RW_MA1_LO;
417     }
418 
419     eth->macaddr[ma][i++] = eth->regs[reg];
420     eth->macaddr[ma][i++] = eth->regs[reg] >> 8;
421     eth->macaddr[ma][i++] = eth->regs[reg] >> 16;
422     eth->macaddr[ma][i++] = eth->regs[reg] >> 24;
423     eth->macaddr[ma][i++] = eth->regs[reg + 1];
424     eth->macaddr[ma][i] = eth->regs[reg + 1] >> 8;
425 
426     D(printf("set mac%d=%x.%x.%x.%x.%x.%x\n", ma,
427              eth->macaddr[ma][0], eth->macaddr[ma][1],
428              eth->macaddr[ma][2], eth->macaddr[ma][3],
429              eth->macaddr[ma][4], eth->macaddr[ma][5]));
430 }
431 
432 static void
433 eth_write(void *opaque, hwaddr addr,
434           uint64_t val64, unsigned int size)
435 {
436     ETRAXFSEthState *eth = opaque;
437     uint32_t value = val64;
438 
439     addr >>= 2;
440     switch (addr) {
441     case RW_MA0_LO:
442     case RW_MA0_HI:
443         eth->regs[addr] = value;
444         eth_update_ma(eth, 0);
445         break;
446     case RW_MA1_LO:
447     case RW_MA1_HI:
448         eth->regs[addr] = value;
449         eth_update_ma(eth, 1);
450         break;
451 
452     case RW_MGM_CTRL:
453         /* Attach an MDIO/PHY abstraction.  */
454         if (value & 2) {
455             eth->mdio_bus.mdio = value & 1;
456         }
457         if (eth->mdio_bus.mdc != (value & 4)) {
458             mdio_cycle(&eth->mdio_bus);
459             eth_validate_duplex(eth);
460         }
461         eth->mdio_bus.mdc = !!(value & 4);
462         eth->regs[addr] = value;
463         break;
464 
465     case RW_REC_CTRL:
466         eth->regs[addr] = value;
467         eth_validate_duplex(eth);
468         break;
469 
470     default:
471         eth->regs[addr] = value;
472         D(printf("%s %x %x\n", __func__, addr, value));
473         break;
474     }
475 }
476 
477 /* The ETRAX FS has a groupt address table (GAT) which works like a k=1 bloom
478    filter dropping group addresses we have not joined.    The filter has 64
479    bits (m). The has function is a simple nible xor of the group addr.    */
480 static int eth_match_groupaddr(ETRAXFSEthState *eth, const unsigned char *sa)
481 {
482     unsigned int hsh;
483     int m_individual = eth->regs[RW_REC_CTRL] & 4;
484     int match;
485 
486     /* First bit on the wire of a MAC address signals multicast or
487        physical address.  */
488     if (!m_individual && !(sa[0] & 1)) {
489         return 0;
490     }
491 
492     /* Calculate the hash index for the GA registers. */
493     hsh = 0;
494     hsh ^= (*sa) & 0x3f;
495     hsh ^= ((*sa) >> 6) & 0x03;
496     ++sa;
497     hsh ^= ((*sa) << 2) & 0x03c;
498     hsh ^= ((*sa) >> 4) & 0xf;
499     ++sa;
500     hsh ^= ((*sa) << 4) & 0x30;
501     hsh ^= ((*sa) >> 2) & 0x3f;
502     ++sa;
503     hsh ^= (*sa) & 0x3f;
504     hsh ^= ((*sa) >> 6) & 0x03;
505     ++sa;
506     hsh ^= ((*sa) << 2) & 0x03c;
507     hsh ^= ((*sa) >> 4) & 0xf;
508     ++sa;
509     hsh ^= ((*sa) << 4) & 0x30;
510     hsh ^= ((*sa) >> 2) & 0x3f;
511 
512     hsh &= 63;
513     if (hsh > 31) {
514         match = eth->regs[RW_GA_HI] & (1 << (hsh - 32));
515     } else {
516         match = eth->regs[RW_GA_LO] & (1 << hsh);
517     }
518     D(printf("hsh=%x ga=%x.%x mtch=%d\n", hsh,
519              eth->regs[RW_GA_HI], eth->regs[RW_GA_LO], match));
520     return match;
521 }
522 
523 static ssize_t eth_receive(NetClientState *nc, const uint8_t *buf, size_t size)
524 {
525     unsigned char sa_bcast[6] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
526     ETRAXFSEthState *eth = qemu_get_nic_opaque(nc);
527     int use_ma0 = eth->regs[RW_REC_CTRL] & 1;
528     int use_ma1 = eth->regs[RW_REC_CTRL] & 2;
529     int r_bcast = eth->regs[RW_REC_CTRL] & 8;
530 
531     if (size < 12) {
532         return -1;
533     }
534 
535     D(printf("%x.%x.%x.%x.%x.%x ma=%d %d bc=%d\n",
536          buf[0], buf[1], buf[2], buf[3], buf[4], buf[5],
537          use_ma0, use_ma1, r_bcast));
538 
539     /* Does the frame get through the address filters?  */
540     if ((!use_ma0 || memcmp(buf, eth->macaddr[0], 6))
541         && (!use_ma1 || memcmp(buf, eth->macaddr[1], 6))
542         && (!r_bcast || memcmp(buf, sa_bcast, 6))
543         && !eth_match_groupaddr(eth, buf)) {
544         return size;
545     }
546 
547     /* FIXME: Find another way to pass on the fake csum.  */
548     etraxfs_dmac_input(eth->dma_in, (void *)buf, size + 4, 1);
549 
550     return size;
551 }
552 
553 static int eth_tx_push(void *opaque, unsigned char *buf, int len, bool eop)
554 {
555     ETRAXFSEthState *eth = opaque;
556 
557     D(printf("%s buf=%p len=%d\n", __func__, buf, len));
558     qemu_send_packet(qemu_get_queue(eth->nic), buf, len);
559     return len;
560 }
561 
562 static void eth_set_link(NetClientState *nc)
563 {
564     ETRAXFSEthState *eth = qemu_get_nic_opaque(nc);
565     D(printf("%s %d\n", __func__, nc->link_down));
566     eth->phy.link = !nc->link_down;
567 }
568 
569 static const MemoryRegionOps eth_ops = {
570     .read = eth_read,
571     .write = eth_write,
572     .endianness = DEVICE_LITTLE_ENDIAN,
573     .valid = {
574         .min_access_size = 4,
575         .max_access_size = 4
576     }
577 };
578 
579 static NetClientInfo net_etraxfs_info = {
580     .type = NET_CLIENT_OPTIONS_KIND_NIC,
581     .size = sizeof(NICState),
582     .receive = eth_receive,
583     .link_status_changed = eth_set_link,
584 };
585 
586 static int fs_eth_init(SysBusDevice *sbd)
587 {
588     DeviceState *dev = DEVICE(sbd);
589     ETRAXFSEthState *s = ETRAX_FS_ETH(dev);
590 
591     if (!s->dma_out || !s->dma_in) {
592         hw_error("Unconnected ETRAX-FS Ethernet MAC.\n");
593     }
594 
595     s->dma_out->client.push = eth_tx_push;
596     s->dma_out->client.opaque = s;
597     s->dma_in->client.opaque = s;
598     s->dma_in->client.pull = NULL;
599 
600     memory_region_init_io(&s->mmio, OBJECT(dev), &eth_ops, s,
601                           "etraxfs-eth", 0x5c);
602     sysbus_init_mmio(sbd, &s->mmio);
603 
604     qemu_macaddr_default_if_unset(&s->conf.macaddr);
605     s->nic = qemu_new_nic(&net_etraxfs_info, &s->conf,
606                           object_get_typename(OBJECT(s)), dev->id, s);
607     qemu_format_nic_info_str(qemu_get_queue(s->nic), s->conf.macaddr.a);
608 
609 
610     tdk_init(&s->phy);
611     mdio_attach(&s->mdio_bus, &s->phy, s->phyaddr);
612     return 0;
613 }
614 
615 static Property etraxfs_eth_properties[] = {
616     DEFINE_PROP_UINT32("phyaddr", ETRAXFSEthState, phyaddr, 1),
617     DEFINE_PROP_PTR("dma_out", ETRAXFSEthState, vdma_out),
618     DEFINE_PROP_PTR("dma_in", ETRAXFSEthState, vdma_in),
619     DEFINE_NIC_PROPERTIES(ETRAXFSEthState, conf),
620     DEFINE_PROP_END_OF_LIST(),
621 };
622 
623 static void etraxfs_eth_class_init(ObjectClass *klass, void *data)
624 {
625     DeviceClass *dc = DEVICE_CLASS(klass);
626     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
627 
628     k->init = fs_eth_init;
629     dc->props = etraxfs_eth_properties;
630     /* Reason: pointer properties "dma_out", "dma_in" */
631     dc->cannot_instantiate_with_device_add_yet = true;
632 }
633 
634 static const TypeInfo etraxfs_eth_info = {
635     .name          = TYPE_ETRAX_FS_ETH,
636     .parent        = TYPE_SYS_BUS_DEVICE,
637     .instance_size = sizeof(ETRAXFSEthState),
638     .class_init    = etraxfs_eth_class_init,
639 };
640 
641 static void etraxfs_eth_register_types(void)
642 {
643     type_register_static(&etraxfs_eth_info);
644 }
645 
646 type_init(etraxfs_eth_register_types)
647