xref: /openbmc/qemu/hw/net/etraxfs_eth.c (revision ba632924)
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 "qemu/osdep.h"
26 #include "qapi/error.h"
27 #include "hw/sysbus.h"
28 #include "net/net.h"
29 #include "hw/cris/etraxfs.h"
30 #include "qemu/error-report.h"
31 #include "trace.h"
32 
33 #define D(x)
34 
35 /* Advertisement control register. */
36 #define ADVERTISE_10HALF        0x0020  /* Try for 10mbps half-duplex  */
37 #define ADVERTISE_10FULL        0x0040  /* Try for 10mbps full-duplex  */
38 #define ADVERTISE_100HALF       0x0080  /* Try for 100mbps half-duplex */
39 #define ADVERTISE_100FULL       0x0100  /* Try for 100mbps full-duplex */
40 
41 /*
42  * The MDIO extensions in the TDK PHY model were reversed engineered from the
43  * linux driver (PHYID and Diagnostics reg).
44  * TODO: Add friendly names for the register nums.
45  */
46 struct qemu_phy
47 {
48     uint32_t regs[32];
49 
50     int link;
51 
52     unsigned int (*read)(struct qemu_phy *phy, unsigned int req);
53     void (*write)(struct qemu_phy *phy, unsigned int req, unsigned int data);
54 };
55 
56 static unsigned int tdk_read(struct qemu_phy *phy, unsigned int req)
57 {
58     int regnum;
59     unsigned r = 0;
60 
61     regnum = req & 0x1f;
62 
63     switch (regnum) {
64     case 1:
65         if (!phy->link) {
66             break;
67         }
68         /* MR1.     */
69         /* Speeds and modes.  */
70         r |= (1 << 13) | (1 << 14);
71         r |= (1 << 11) | (1 << 12);
72         r |= (1 << 5); /* Autoneg complete.  */
73         r |= (1 << 3); /* Autoneg able.     */
74         r |= (1 << 2); /* link.     */
75         break;
76     case 5:
77         /* Link partner ability.
78            We are kind; always agree with whatever best mode
79            the guest advertises.  */
80         r = 1 << 14; /* Success.  */
81         /* Copy advertised modes.  */
82         r |= phy->regs[4] & (15 << 5);
83         /* Autoneg support.  */
84         r |= 1;
85         break;
86     case 18:
87     {
88         /* Diagnostics reg.  */
89         int duplex = 0;
90         int speed_100 = 0;
91 
92         if (!phy->link) {
93             break;
94         }
95 
96         /* Are we advertising 100 half or 100 duplex ? */
97         speed_100 = !!(phy->regs[4] & ADVERTISE_100HALF);
98         speed_100 |= !!(phy->regs[4] & ADVERTISE_100FULL);
99 
100         /* Are we advertising 10 duplex or 100 duplex ? */
101         duplex = !!(phy->regs[4] & ADVERTISE_100FULL);
102         duplex |= !!(phy->regs[4] & ADVERTISE_10FULL);
103         r = (speed_100 << 10) | (duplex << 11);
104     }
105     break;
106 
107     default:
108         r = phy->regs[regnum];
109         break;
110     }
111     trace_mdio_phy_read(regnum, r);
112     return r;
113 }
114 
115 static void
116 tdk_write(struct qemu_phy *phy, unsigned int req, unsigned int data)
117 {
118     int regnum;
119 
120     regnum = req & 0x1f;
121     trace_mdio_phy_write(regnum, data);
122     switch (regnum) {
123     default:
124         phy->regs[regnum] = data;
125         break;
126     }
127 }
128 
129 static void
130 tdk_reset(struct qemu_phy *phy)
131 {
132     phy->regs[0] = 0x3100;
133     /* PHY Id.  */
134     phy->regs[2] = 0x0300;
135     phy->regs[3] = 0xe400;
136     /* Autonegotiation advertisement reg.  */
137     phy->regs[4] = 0x01E1;
138     phy->link = 1;
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     trace_mdio_bitbang(bus->mdc, bus->mdio, bus->state, bus->cnt, bus->drive);
209 #if 0
210     if (bus->mdc) {
211         printf("%d", bus->mdio);
212     }
213 #endif
214     switch (bus->state) {
215     case PREAMBLE:
216         if (bus->mdc) {
217             if (bus->cnt >= (32 * 2) && !bus->mdio) {
218                 bus->cnt = 0;
219                 bus->state = SOF;
220                 bus->data = 0;
221             }
222         }
223         break;
224     case SOF:
225         if (bus->mdc) {
226             if (bus->mdio != 1) {
227                 printf("WARNING: no SOF\n");
228             }
229             if (bus->cnt == 1*2) {
230                 bus->cnt = 0;
231                 bus->opc = 0;
232                 bus->state = OPC;
233             }
234         }
235         break;
236     case OPC:
237         if (bus->mdc) {
238             bus->opc <<= 1;
239             bus->opc |= bus->mdio & 1;
240             if (bus->cnt == 2*2) {
241                 bus->cnt = 0;
242                 bus->addr = 0;
243                 bus->state = ADDR;
244             }
245         }
246         break;
247     case ADDR:
248         if (bus->mdc) {
249             bus->addr <<= 1;
250             bus->addr |= bus->mdio & 1;
251 
252             if (bus->cnt == 5*2) {
253                 bus->cnt = 0;
254                 bus->req = 0;
255                 bus->state = REQ;
256             }
257         }
258         break;
259     case REQ:
260         if (bus->mdc) {
261             bus->req <<= 1;
262             bus->req |= bus->mdio & 1;
263             if (bus->cnt == 5*2) {
264                 bus->cnt = 0;
265                 bus->state = TURNAROUND;
266             }
267         }
268         break;
269     case TURNAROUND:
270         if (bus->mdc && bus->cnt == 2*2) {
271             bus->mdio = 0;
272             bus->cnt = 0;
273 
274             if (bus->opc == 2) {
275                 bus->drive = 1;
276                 mdio_read_req(bus);
277                 bus->mdio = bus->data & 1;
278             }
279             bus->state = DATA;
280         }
281         break;
282     case DATA:
283         if (!bus->mdc) {
284             if (bus->drive) {
285                 bus->mdio = !!(bus->data & (1 << 15));
286                 bus->data <<= 1;
287             }
288         } else {
289             if (!bus->drive) {
290                 bus->data <<= 1;
291                 bus->data |= bus->mdio;
292             }
293             if (bus->cnt == 16 * 2) {
294                 bus->cnt = 0;
295                 bus->state = PREAMBLE;
296                 if (!bus->drive) {
297                     mdio_write_req(bus);
298                 }
299                 bus->drive = 0;
300             }
301         }
302         break;
303     default:
304         break;
305     }
306 }
307 
308 /* ETRAX-FS Ethernet MAC block starts here.  */
309 
310 #define RW_MA0_LO      0x00
311 #define RW_MA0_HI      0x01
312 #define RW_MA1_LO      0x02
313 #define RW_MA1_HI      0x03
314 #define RW_GA_LO      0x04
315 #define RW_GA_HI      0x05
316 #define RW_GEN_CTRL      0x06
317 #define RW_REC_CTRL      0x07
318 #define RW_TR_CTRL      0x08
319 #define RW_CLR_ERR      0x09
320 #define RW_MGM_CTRL      0x0a
321 #define R_STAT          0x0b
322 #define FS_ETH_MAX_REGS      0x17
323 
324 #define TYPE_ETRAX_FS_ETH "etraxfs-eth"
325 #define ETRAX_FS_ETH(obj) \
326     OBJECT_CHECK(ETRAXFSEthState, (obj), TYPE_ETRAX_FS_ETH)
327 
328 typedef struct ETRAXFSEthState
329 {
330     SysBusDevice parent_obj;
331 
332     MemoryRegion mmio;
333     NICState *nic;
334     NICConf conf;
335 
336     /* Two addrs in the filter.  */
337     uint8_t macaddr[2][6];
338     uint32_t regs[FS_ETH_MAX_REGS];
339 
340     union {
341         void *vdma_out;
342         struct etraxfs_dma_client *dma_out;
343     };
344     union {
345         void *vdma_in;
346         struct etraxfs_dma_client *dma_in;
347     };
348 
349     /* MDIO bus.  */
350     struct qemu_mdio mdio_bus;
351     unsigned int phyaddr;
352     int duplex_mismatch;
353 
354     /* PHY.     */
355     struct qemu_phy phy;
356 } ETRAXFSEthState;
357 
358 static void eth_validate_duplex(ETRAXFSEthState *eth)
359 {
360     struct qemu_phy *phy;
361     unsigned int phy_duplex;
362     unsigned int mac_duplex;
363     int new_mm = 0;
364 
365     phy = eth->mdio_bus.devs[eth->phyaddr];
366     phy_duplex = !!(phy->read(phy, 18) & (1 << 11));
367     mac_duplex = !!(eth->regs[RW_REC_CTRL] & 128);
368 
369     if (mac_duplex != phy_duplex) {
370         new_mm = 1;
371     }
372 
373     if (eth->regs[RW_GEN_CTRL] & 1) {
374         if (new_mm != eth->duplex_mismatch) {
375             if (new_mm) {
376                 printf("HW: WARNING ETH duplex mismatch MAC=%d PHY=%d\n",
377                        mac_duplex, phy_duplex);
378             } else {
379                 printf("HW: ETH duplex ok.\n");
380             }
381         }
382         eth->duplex_mismatch = new_mm;
383     }
384 }
385 
386 static uint64_t
387 eth_read(void *opaque, hwaddr addr, unsigned int size)
388 {
389     ETRAXFSEthState *eth = opaque;
390     uint32_t r = 0;
391 
392     addr >>= 2;
393 
394     switch (addr) {
395     case R_STAT:
396         r = eth->mdio_bus.mdio & 1;
397         break;
398     default:
399         r = eth->regs[addr];
400         D(printf("%s %x\n", __func__, addr * 4));
401         break;
402     }
403     return r;
404 }
405 
406 static void eth_update_ma(ETRAXFSEthState *eth, int ma)
407 {
408     int reg;
409     int i = 0;
410 
411     ma &= 1;
412 
413     reg = RW_MA0_LO;
414     if (ma) {
415         reg = RW_MA1_LO;
416     }
417 
418     eth->macaddr[ma][i++] = eth->regs[reg];
419     eth->macaddr[ma][i++] = eth->regs[reg] >> 8;
420     eth->macaddr[ma][i++] = eth->regs[reg] >> 16;
421     eth->macaddr[ma][i++] = eth->regs[reg] >> 24;
422     eth->macaddr[ma][i++] = eth->regs[reg + 1];
423     eth->macaddr[ma][i] = eth->regs[reg + 1] >> 8;
424 
425     D(printf("set mac%d=%x.%x.%x.%x.%x.%x\n", ma,
426              eth->macaddr[ma][0], eth->macaddr[ma][1],
427              eth->macaddr[ma][2], eth->macaddr[ma][3],
428              eth->macaddr[ma][4], eth->macaddr[ma][5]));
429 }
430 
431 static void
432 eth_write(void *opaque, hwaddr addr,
433           uint64_t val64, unsigned int size)
434 {
435     ETRAXFSEthState *eth = opaque;
436     uint32_t value = val64;
437 
438     addr >>= 2;
439     switch (addr) {
440     case RW_MA0_LO:
441     case RW_MA0_HI:
442         eth->regs[addr] = value;
443         eth_update_ma(eth, 0);
444         break;
445     case RW_MA1_LO:
446     case RW_MA1_HI:
447         eth->regs[addr] = value;
448         eth_update_ma(eth, 1);
449         break;
450 
451     case RW_MGM_CTRL:
452         /* Attach an MDIO/PHY abstraction.  */
453         if (value & 2) {
454             eth->mdio_bus.mdio = value & 1;
455         }
456         if (eth->mdio_bus.mdc != (value & 4)) {
457             mdio_cycle(&eth->mdio_bus);
458             eth_validate_duplex(eth);
459         }
460         eth->mdio_bus.mdc = !!(value & 4);
461         eth->regs[addr] = value;
462         break;
463 
464     case RW_REC_CTRL:
465         eth->regs[addr] = value;
466         eth_validate_duplex(eth);
467         break;
468 
469     default:
470         eth->regs[addr] = value;
471         D(printf("%s %x %x\n", __func__, addr, value));
472         break;
473     }
474 }
475 
476 /* The ETRAX FS has a groupt address table (GAT) which works like a k=1 bloom
477    filter dropping group addresses we have not joined.    The filter has 64
478    bits (m). The has function is a simple nible xor of the group addr.    */
479 static int eth_match_groupaddr(ETRAXFSEthState *eth, const unsigned char *sa)
480 {
481     unsigned int hsh;
482     int m_individual = eth->regs[RW_REC_CTRL] & 4;
483     int match;
484 
485     /* First bit on the wire of a MAC address signals multicast or
486        physical address.  */
487     if (!m_individual && !(sa[0] & 1)) {
488         return 0;
489     }
490 
491     /* Calculate the hash index for the GA registers. */
492     hsh = 0;
493     hsh ^= (*sa) & 0x3f;
494     hsh ^= ((*sa) >> 6) & 0x03;
495     ++sa;
496     hsh ^= ((*sa) << 2) & 0x03c;
497     hsh ^= ((*sa) >> 4) & 0xf;
498     ++sa;
499     hsh ^= ((*sa) << 4) & 0x30;
500     hsh ^= ((*sa) >> 2) & 0x3f;
501     ++sa;
502     hsh ^= (*sa) & 0x3f;
503     hsh ^= ((*sa) >> 6) & 0x03;
504     ++sa;
505     hsh ^= ((*sa) << 2) & 0x03c;
506     hsh ^= ((*sa) >> 4) & 0xf;
507     ++sa;
508     hsh ^= ((*sa) << 4) & 0x30;
509     hsh ^= ((*sa) >> 2) & 0x3f;
510 
511     hsh &= 63;
512     if (hsh > 31) {
513         match = eth->regs[RW_GA_HI] & (1 << (hsh - 32));
514     } else {
515         match = eth->regs[RW_GA_LO] & (1 << hsh);
516     }
517     D(printf("hsh=%x ga=%x.%x mtch=%d\n", hsh,
518              eth->regs[RW_GA_HI], eth->regs[RW_GA_LO], match));
519     return match;
520 }
521 
522 static ssize_t eth_receive(NetClientState *nc, const uint8_t *buf, size_t size)
523 {
524     unsigned char sa_bcast[6] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
525     ETRAXFSEthState *eth = qemu_get_nic_opaque(nc);
526     int use_ma0 = eth->regs[RW_REC_CTRL] & 1;
527     int use_ma1 = eth->regs[RW_REC_CTRL] & 2;
528     int r_bcast = eth->regs[RW_REC_CTRL] & 8;
529 
530     if (size < 12) {
531         return -1;
532     }
533 
534     D(printf("%x.%x.%x.%x.%x.%x ma=%d %d bc=%d\n",
535          buf[0], buf[1], buf[2], buf[3], buf[4], buf[5],
536          use_ma0, use_ma1, r_bcast));
537 
538     /* Does the frame get through the address filters?  */
539     if ((!use_ma0 || memcmp(buf, eth->macaddr[0], 6))
540         && (!use_ma1 || memcmp(buf, eth->macaddr[1], 6))
541         && (!r_bcast || memcmp(buf, sa_bcast, 6))
542         && !eth_match_groupaddr(eth, buf)) {
543         return size;
544     }
545 
546     /* FIXME: Find another way to pass on the fake csum.  */
547     etraxfs_dmac_input(eth->dma_in, (void *)buf, size + 4, 1);
548 
549     return size;
550 }
551 
552 static int eth_tx_push(void *opaque, unsigned char *buf, int len, bool eop)
553 {
554     ETRAXFSEthState *eth = opaque;
555 
556     D(printf("%s buf=%p len=%d\n", __func__, buf, len));
557     qemu_send_packet(qemu_get_queue(eth->nic), buf, len);
558     return len;
559 }
560 
561 static void eth_set_link(NetClientState *nc)
562 {
563     ETRAXFSEthState *eth = qemu_get_nic_opaque(nc);
564     D(printf("%s %d\n", __func__, nc->link_down));
565     eth->phy.link = !nc->link_down;
566 }
567 
568 static const MemoryRegionOps eth_ops = {
569     .read = eth_read,
570     .write = eth_write,
571     .endianness = DEVICE_LITTLE_ENDIAN,
572     .valid = {
573         .min_access_size = 4,
574         .max_access_size = 4
575     }
576 };
577 
578 static NetClientInfo net_etraxfs_info = {
579     .type = NET_CLIENT_DRIVER_NIC,
580     .size = sizeof(NICState),
581     .receive = eth_receive,
582     .link_status_changed = eth_set_link,
583 };
584 
585 static void etraxfs_eth_reset(DeviceState *dev)
586 {
587     ETRAXFSEthState *s = ETRAX_FS_ETH(dev);
588 
589     memset(s->regs, 0, sizeof(s->regs));
590     memset(s->macaddr, 0, sizeof(s->macaddr));
591     s->duplex_mismatch = 0;
592 
593     s->mdio_bus.mdc = 0;
594     s->mdio_bus.mdio = 0;
595     s->mdio_bus.state = 0;
596     s->mdio_bus.drive = 0;
597     s->mdio_bus.cnt = 0;
598     s->mdio_bus.addr = 0;
599     s->mdio_bus.opc = 0;
600     s->mdio_bus.req = 0;
601     s->mdio_bus.data = 0;
602 
603     tdk_reset(&s->phy);
604 }
605 
606 static void etraxfs_eth_realize(DeviceState *dev, Error **errp)
607 {
608     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
609     ETRAXFSEthState *s = ETRAX_FS_ETH(dev);
610 
611     if (!s->dma_out || !s->dma_in) {
612         error_setg(errp, "Unconnected ETRAX-FS Ethernet MAC");
613         return;
614     }
615 
616     s->dma_out->client.push = eth_tx_push;
617     s->dma_out->client.opaque = s;
618     s->dma_in->client.opaque = s;
619     s->dma_in->client.pull = NULL;
620 
621     memory_region_init_io(&s->mmio, OBJECT(dev), &eth_ops, s,
622                           "etraxfs-eth", 0x5c);
623     sysbus_init_mmio(sbd, &s->mmio);
624 
625     qemu_macaddr_default_if_unset(&s->conf.macaddr);
626     s->nic = qemu_new_nic(&net_etraxfs_info, &s->conf,
627                           object_get_typename(OBJECT(s)), dev->id, s);
628     qemu_format_nic_info_str(qemu_get_queue(s->nic), s->conf.macaddr.a);
629 
630     s->phy.read = tdk_read;
631     s->phy.write = tdk_write;
632     mdio_attach(&s->mdio_bus, &s->phy, s->phyaddr);
633 }
634 
635 static Property etraxfs_eth_properties[] = {
636     DEFINE_PROP_UINT32("phyaddr", ETRAXFSEthState, phyaddr, 1),
637     DEFINE_PROP_PTR("dma_out", ETRAXFSEthState, vdma_out),
638     DEFINE_PROP_PTR("dma_in", ETRAXFSEthState, vdma_in),
639     DEFINE_NIC_PROPERTIES(ETRAXFSEthState, conf),
640     DEFINE_PROP_END_OF_LIST(),
641 };
642 
643 static void etraxfs_eth_class_init(ObjectClass *klass, void *data)
644 {
645     DeviceClass *dc = DEVICE_CLASS(klass);
646 
647     dc->realize = etraxfs_eth_realize;
648     dc->reset = etraxfs_eth_reset;
649     dc->props = etraxfs_eth_properties;
650     /* Reason: pointer properties "dma_out", "dma_in" */
651     dc->user_creatable = false;
652 }
653 
654 static const TypeInfo etraxfs_eth_info = {
655     .name          = TYPE_ETRAX_FS_ETH,
656     .parent        = TYPE_SYS_BUS_DEVICE,
657     .instance_size = sizeof(ETRAXFSEthState),
658     .class_init    = etraxfs_eth_class_init,
659 };
660 
661 static void etraxfs_eth_register_types(void)
662 {
663     type_register_static(&etraxfs_eth_info);
664 }
665 
666 type_init(etraxfs_eth_register_types)
667