xref: /openbmc/qemu/hw/net/etraxfs_eth.c (revision 4e6b1384)
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 "qemu/module.h"
32 #include "trace.h"
33 
34 #define D(x)
35 
36 /* Advertisement control register. */
37 #define ADVERTISE_10HALF        0x0020  /* Try for 10mbps half-duplex  */
38 #define ADVERTISE_10FULL        0x0040  /* Try for 10mbps full-duplex  */
39 #define ADVERTISE_100HALF       0x0080  /* Try for 100mbps half-duplex */
40 #define ADVERTISE_100FULL       0x0100  /* Try for 100mbps full-duplex */
41 
42 /*
43  * The MDIO extensions in the TDK PHY model were reversed engineered from the
44  * linux driver (PHYID and Diagnostics reg).
45  * TODO: Add friendly names for the register nums.
46  */
47 struct qemu_phy
48 {
49     uint32_t regs[32];
50 
51     int link;
52 
53     unsigned int (*read)(struct qemu_phy *phy, unsigned int req);
54     void (*write)(struct qemu_phy *phy, unsigned int req, unsigned int data);
55 };
56 
57 static unsigned int tdk_read(struct qemu_phy *phy, unsigned int req)
58 {
59     int regnum;
60     unsigned r = 0;
61 
62     regnum = req & 0x1f;
63 
64     switch (regnum) {
65     case 1:
66         if (!phy->link) {
67             break;
68         }
69         /* MR1.     */
70         /* Speeds and modes.  */
71         r |= (1 << 13) | (1 << 14);
72         r |= (1 << 11) | (1 << 12);
73         r |= (1 << 5); /* Autoneg complete.  */
74         r |= (1 << 3); /* Autoneg able.     */
75         r |= (1 << 2); /* link.     */
76         break;
77     case 5:
78         /* Link partner ability.
79            We are kind; always agree with whatever best mode
80            the guest advertises.  */
81         r = 1 << 14; /* Success.  */
82         /* Copy advertised modes.  */
83         r |= phy->regs[4] & (15 << 5);
84         /* Autoneg support.  */
85         r |= 1;
86         break;
87     case 18:
88     {
89         /* Diagnostics reg.  */
90         int duplex = 0;
91         int speed_100 = 0;
92 
93         if (!phy->link) {
94             break;
95         }
96 
97         /* Are we advertising 100 half or 100 duplex ? */
98         speed_100 = !!(phy->regs[4] & ADVERTISE_100HALF);
99         speed_100 |= !!(phy->regs[4] & ADVERTISE_100FULL);
100 
101         /* Are we advertising 10 duplex or 100 duplex ? */
102         duplex = !!(phy->regs[4] & ADVERTISE_100FULL);
103         duplex |= !!(phy->regs[4] & ADVERTISE_10FULL);
104         r = (speed_100 << 10) | (duplex << 11);
105     }
106     break;
107 
108     default:
109         r = phy->regs[regnum];
110         break;
111     }
112     trace_mdio_phy_read(regnum, r);
113     return r;
114 }
115 
116 static void
117 tdk_write(struct qemu_phy *phy, unsigned int req, unsigned int data)
118 {
119     int regnum;
120 
121     regnum = req & 0x1f;
122     trace_mdio_phy_write(regnum, data);
123     switch (regnum) {
124     default:
125         phy->regs[regnum] = data;
126         break;
127     }
128 }
129 
130 static void
131 tdk_reset(struct qemu_phy *phy)
132 {
133     phy->regs[0] = 0x3100;
134     /* PHY Id.  */
135     phy->regs[2] = 0x0300;
136     phy->regs[3] = 0xe400;
137     /* Autonegotiation advertisement reg.  */
138     phy->regs[4] = 0x01E1;
139     phy->link = 1;
140 }
141 
142 struct qemu_mdio
143 {
144     /* bus.     */
145     int mdc;
146     int mdio;
147 
148     /* decoder.  */
149     enum {
150         PREAMBLE,
151         SOF,
152         OPC,
153         ADDR,
154         REQ,
155         TURNAROUND,
156         DATA
157     } state;
158     unsigned int drive;
159 
160     unsigned int cnt;
161     unsigned int addr;
162     unsigned int opc;
163     unsigned int req;
164     unsigned int data;
165 
166     struct qemu_phy *devs[32];
167 };
168 
169 static void
170 mdio_attach(struct qemu_mdio *bus, struct qemu_phy *phy, unsigned int addr)
171 {
172     bus->devs[addr & 0x1f] = phy;
173 }
174 
175 #ifdef USE_THIS_DEAD_CODE
176 static void
177 mdio_detach(struct qemu_mdio *bus, struct qemu_phy *phy, unsigned int addr)
178 {
179     bus->devs[addr & 0x1f] = NULL;
180 }
181 #endif
182 
183 static void mdio_read_req(struct qemu_mdio *bus)
184 {
185     struct qemu_phy *phy;
186 
187     phy = bus->devs[bus->addr];
188     if (phy && phy->read) {
189         bus->data = phy->read(phy, bus->req);
190     } else {
191         bus->data = 0xffff;
192     }
193 }
194 
195 static void mdio_write_req(struct qemu_mdio *bus)
196 {
197     struct qemu_phy *phy;
198 
199     phy = bus->devs[bus->addr];
200     if (phy && phy->write) {
201         phy->write(phy, bus->req, bus->data);
202     }
203 }
204 
205 static void mdio_cycle(struct qemu_mdio *bus)
206 {
207     bus->cnt++;
208 
209     trace_mdio_bitbang(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     struct etraxfs_dma_client *dma_out;
342     struct etraxfs_dma_client *dma_in;
343 
344     /* MDIO bus.  */
345     struct qemu_mdio mdio_bus;
346     unsigned int phyaddr;
347     int duplex_mismatch;
348 
349     /* PHY.     */
350     struct qemu_phy phy;
351 } ETRAXFSEthState;
352 
353 static void eth_validate_duplex(ETRAXFSEthState *eth)
354 {
355     struct qemu_phy *phy;
356     unsigned int phy_duplex;
357     unsigned int mac_duplex;
358     int new_mm = 0;
359 
360     phy = eth->mdio_bus.devs[eth->phyaddr];
361     phy_duplex = !!(phy->read(phy, 18) & (1 << 11));
362     mac_duplex = !!(eth->regs[RW_REC_CTRL] & 128);
363 
364     if (mac_duplex != phy_duplex) {
365         new_mm = 1;
366     }
367 
368     if (eth->regs[RW_GEN_CTRL] & 1) {
369         if (new_mm != eth->duplex_mismatch) {
370             if (new_mm) {
371                 printf("HW: WARNING ETH duplex mismatch MAC=%d PHY=%d\n",
372                        mac_duplex, phy_duplex);
373             } else {
374                 printf("HW: ETH duplex ok.\n");
375             }
376         }
377         eth->duplex_mismatch = new_mm;
378     }
379 }
380 
381 static uint64_t
382 eth_read(void *opaque, hwaddr addr, unsigned int size)
383 {
384     ETRAXFSEthState *eth = opaque;
385     uint32_t r = 0;
386 
387     addr >>= 2;
388 
389     switch (addr) {
390     case R_STAT:
391         r = eth->mdio_bus.mdio & 1;
392         break;
393     default:
394         r = eth->regs[addr];
395         D(printf("%s %x\n", __func__, addr * 4));
396         break;
397     }
398     return r;
399 }
400 
401 static void eth_update_ma(ETRAXFSEthState *eth, int ma)
402 {
403     int reg;
404     int i = 0;
405 
406     ma &= 1;
407 
408     reg = RW_MA0_LO;
409     if (ma) {
410         reg = RW_MA1_LO;
411     }
412 
413     eth->macaddr[ma][i++] = eth->regs[reg];
414     eth->macaddr[ma][i++] = eth->regs[reg] >> 8;
415     eth->macaddr[ma][i++] = eth->regs[reg] >> 16;
416     eth->macaddr[ma][i++] = eth->regs[reg] >> 24;
417     eth->macaddr[ma][i++] = eth->regs[reg + 1];
418     eth->macaddr[ma][i] = eth->regs[reg + 1] >> 8;
419 
420     D(printf("set mac%d=%x.%x.%x.%x.%x.%x\n", ma,
421              eth->macaddr[ma][0], eth->macaddr[ma][1],
422              eth->macaddr[ma][2], eth->macaddr[ma][3],
423              eth->macaddr[ma][4], eth->macaddr[ma][5]));
424 }
425 
426 static void
427 eth_write(void *opaque, hwaddr addr,
428           uint64_t val64, unsigned int size)
429 {
430     ETRAXFSEthState *eth = opaque;
431     uint32_t value = val64;
432 
433     addr >>= 2;
434     switch (addr) {
435     case RW_MA0_LO:
436     case RW_MA0_HI:
437         eth->regs[addr] = value;
438         eth_update_ma(eth, 0);
439         break;
440     case RW_MA1_LO:
441     case RW_MA1_HI:
442         eth->regs[addr] = value;
443         eth_update_ma(eth, 1);
444         break;
445 
446     case RW_MGM_CTRL:
447         /* Attach an MDIO/PHY abstraction.  */
448         if (value & 2) {
449             eth->mdio_bus.mdio = value & 1;
450         }
451         if (eth->mdio_bus.mdc != (value & 4)) {
452             mdio_cycle(&eth->mdio_bus);
453             eth_validate_duplex(eth);
454         }
455         eth->mdio_bus.mdc = !!(value & 4);
456         eth->regs[addr] = value;
457         break;
458 
459     case RW_REC_CTRL:
460         eth->regs[addr] = value;
461         eth_validate_duplex(eth);
462         break;
463 
464     default:
465         eth->regs[addr] = value;
466         D(printf("%s %x %x\n", __func__, addr, value));
467         break;
468     }
469 }
470 
471 /* The ETRAX FS has a groupt address table (GAT) which works like a k=1 bloom
472    filter dropping group addresses we have not joined.    The filter has 64
473    bits (m). The has function is a simple nible xor of the group addr.    */
474 static int eth_match_groupaddr(ETRAXFSEthState *eth, const unsigned char *sa)
475 {
476     unsigned int hsh;
477     int m_individual = eth->regs[RW_REC_CTRL] & 4;
478     int match;
479 
480     /* First bit on the wire of a MAC address signals multicast or
481        physical address.  */
482     if (!m_individual && !(sa[0] & 1)) {
483         return 0;
484     }
485 
486     /* Calculate the hash index for the GA registers. */
487     hsh = 0;
488     hsh ^= (*sa) & 0x3f;
489     hsh ^= ((*sa) >> 6) & 0x03;
490     ++sa;
491     hsh ^= ((*sa) << 2) & 0x03c;
492     hsh ^= ((*sa) >> 4) & 0xf;
493     ++sa;
494     hsh ^= ((*sa) << 4) & 0x30;
495     hsh ^= ((*sa) >> 2) & 0x3f;
496     ++sa;
497     hsh ^= (*sa) & 0x3f;
498     hsh ^= ((*sa) >> 6) & 0x03;
499     ++sa;
500     hsh ^= ((*sa) << 2) & 0x03c;
501     hsh ^= ((*sa) >> 4) & 0xf;
502     ++sa;
503     hsh ^= ((*sa) << 4) & 0x30;
504     hsh ^= ((*sa) >> 2) & 0x3f;
505 
506     hsh &= 63;
507     if (hsh > 31) {
508         match = eth->regs[RW_GA_HI] & (1 << (hsh - 32));
509     } else {
510         match = eth->regs[RW_GA_LO] & (1 << hsh);
511     }
512     D(printf("hsh=%x ga=%x.%x mtch=%d\n", hsh,
513              eth->regs[RW_GA_HI], eth->regs[RW_GA_LO], match));
514     return match;
515 }
516 
517 static ssize_t eth_receive(NetClientState *nc, const uint8_t *buf, size_t size)
518 {
519     unsigned char sa_bcast[6] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
520     ETRAXFSEthState *eth = qemu_get_nic_opaque(nc);
521     int use_ma0 = eth->regs[RW_REC_CTRL] & 1;
522     int use_ma1 = eth->regs[RW_REC_CTRL] & 2;
523     int r_bcast = eth->regs[RW_REC_CTRL] & 8;
524 
525     if (size < 12) {
526         return -1;
527     }
528 
529     D(printf("%x.%x.%x.%x.%x.%x ma=%d %d bc=%d\n",
530          buf[0], buf[1], buf[2], buf[3], buf[4], buf[5],
531          use_ma0, use_ma1, r_bcast));
532 
533     /* Does the frame get through the address filters?  */
534     if ((!use_ma0 || memcmp(buf, eth->macaddr[0], 6))
535         && (!use_ma1 || memcmp(buf, eth->macaddr[1], 6))
536         && (!r_bcast || memcmp(buf, sa_bcast, 6))
537         && !eth_match_groupaddr(eth, buf)) {
538         return size;
539     }
540 
541     /* FIXME: Find another way to pass on the fake csum.  */
542     etraxfs_dmac_input(eth->dma_in, (void *)buf, size + 4, 1);
543 
544     return size;
545 }
546 
547 static int eth_tx_push(void *opaque, unsigned char *buf, int len, bool eop)
548 {
549     ETRAXFSEthState *eth = opaque;
550 
551     D(printf("%s buf=%p len=%d\n", __func__, buf, len));
552     qemu_send_packet(qemu_get_queue(eth->nic), buf, len);
553     return len;
554 }
555 
556 static void eth_set_link(NetClientState *nc)
557 {
558     ETRAXFSEthState *eth = qemu_get_nic_opaque(nc);
559     D(printf("%s %d\n", __func__, nc->link_down));
560     eth->phy.link = !nc->link_down;
561 }
562 
563 static const MemoryRegionOps eth_ops = {
564     .read = eth_read,
565     .write = eth_write,
566     .endianness = DEVICE_LITTLE_ENDIAN,
567     .valid = {
568         .min_access_size = 4,
569         .max_access_size = 4
570     }
571 };
572 
573 static NetClientInfo net_etraxfs_info = {
574     .type = NET_CLIENT_DRIVER_NIC,
575     .size = sizeof(NICState),
576     .receive = eth_receive,
577     .link_status_changed = eth_set_link,
578 };
579 
580 static void etraxfs_eth_reset(DeviceState *dev)
581 {
582     ETRAXFSEthState *s = ETRAX_FS_ETH(dev);
583 
584     memset(s->regs, 0, sizeof(s->regs));
585     memset(s->macaddr, 0, sizeof(s->macaddr));
586     s->duplex_mismatch = 0;
587 
588     s->mdio_bus.mdc = 0;
589     s->mdio_bus.mdio = 0;
590     s->mdio_bus.state = 0;
591     s->mdio_bus.drive = 0;
592     s->mdio_bus.cnt = 0;
593     s->mdio_bus.addr = 0;
594     s->mdio_bus.opc = 0;
595     s->mdio_bus.req = 0;
596     s->mdio_bus.data = 0;
597 
598     tdk_reset(&s->phy);
599 }
600 
601 static void etraxfs_eth_realize(DeviceState *dev, Error **errp)
602 {
603     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
604     ETRAXFSEthState *s = ETRAX_FS_ETH(dev);
605 
606     if (!s->dma_out || !s->dma_in) {
607         error_setg(errp, "Unconnected ETRAX-FS Ethernet MAC");
608         return;
609     }
610 
611     s->dma_out->client.push = eth_tx_push;
612     s->dma_out->client.opaque = s;
613     s->dma_in->client.opaque = s;
614     s->dma_in->client.pull = NULL;
615 
616     memory_region_init_io(&s->mmio, OBJECT(dev), &eth_ops, s,
617                           "etraxfs-eth", 0x5c);
618     sysbus_init_mmio(sbd, &s->mmio);
619 
620     qemu_macaddr_default_if_unset(&s->conf.macaddr);
621     s->nic = qemu_new_nic(&net_etraxfs_info, &s->conf,
622                           object_get_typename(OBJECT(s)), dev->id, s);
623     qemu_format_nic_info_str(qemu_get_queue(s->nic), s->conf.macaddr.a);
624 
625     s->phy.read = tdk_read;
626     s->phy.write = tdk_write;
627     mdio_attach(&s->mdio_bus, &s->phy, s->phyaddr);
628 }
629 
630 static Property etraxfs_eth_properties[] = {
631     DEFINE_PROP_UINT32("phyaddr", ETRAXFSEthState, phyaddr, 1),
632     DEFINE_NIC_PROPERTIES(ETRAXFSEthState, conf),
633     DEFINE_PROP_END_OF_LIST(),
634 };
635 
636 static void etraxfs_eth_class_init(ObjectClass *klass, void *data)
637 {
638     DeviceClass *dc = DEVICE_CLASS(klass);
639 
640     dc->realize = etraxfs_eth_realize;
641     dc->reset = etraxfs_eth_reset;
642     dc->props = etraxfs_eth_properties;
643     /* Reason: dma_out, dma_in are not user settable */
644     dc->user_creatable = false;
645 }
646 
647 
648 /* Instantiate an ETRAXFS Ethernet MAC.  */
649 DeviceState *
650 etraxfs_eth_init(NICInfo *nd, hwaddr base, int phyaddr,
651                  struct etraxfs_dma_client *dma_out,
652                  struct etraxfs_dma_client *dma_in)
653 {
654     DeviceState *dev;
655     qemu_check_nic_model(nd, "fseth");
656 
657     dev = qdev_create(NULL, "etraxfs-eth");
658     qdev_set_nic_properties(dev, nd);
659     qdev_prop_set_uint32(dev, "phyaddr", phyaddr);
660 
661     /*
662      * TODO: QOM design, define a QOM interface for "I am an etraxfs
663      * DMA client" (which replaces the current 'struct
664      * etraxfs_dma_client' ad-hoc interface), implement it on the
665      * ethernet device, and then have QOM link properties on the DMA
666      * controller device so that you can pass the interface
667      * implementations to it.
668      */
669     ETRAX_FS_ETH(dev)->dma_out = dma_out;
670     ETRAX_FS_ETH(dev)->dma_in = dma_in;
671     qdev_init_nofail(dev);
672     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, base);
673 
674     return dev;
675 }
676 
677 static const TypeInfo etraxfs_eth_info = {
678     .name          = TYPE_ETRAX_FS_ETH,
679     .parent        = TYPE_SYS_BUS_DEVICE,
680     .instance_size = sizeof(ETRAXFSEthState),
681     .class_init    = etraxfs_eth_class_init,
682 };
683 
684 static void etraxfs_eth_register_types(void)
685 {
686     type_register_static(&etraxfs_eth_info);
687 }
688 
689 type_init(etraxfs_eth_register_types)
690