xref: /openbmc/qemu/hw/net/etraxfs_eth.c (revision ee3d1f1b)
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 #include "qom/object.h"
34 
35 #define D(x)
36 
37 /* Advertisement control register. */
38 #define ADVERTISE_10HALF        0x0020  /* Try for 10mbps half-duplex  */
39 #define ADVERTISE_10FULL        0x0040  /* Try for 10mbps full-duplex  */
40 #define ADVERTISE_100HALF       0x0080  /* Try for 100mbps half-duplex */
41 #define ADVERTISE_100FULL       0x0100  /* Try for 100mbps full-duplex */
42 
43 /*
44  * The MDIO extensions in the TDK PHY model were reversed engineered from the
45  * linux driver (PHYID and Diagnostics reg).
46  * TODO: Add friendly names for the register nums.
47  */
48 struct qemu_phy
49 {
50     uint32_t regs[32];
51 
52     int link;
53 
54     unsigned int (*read)(struct qemu_phy *phy, unsigned int req);
55     void (*write)(struct qemu_phy *phy, unsigned int req, unsigned int data);
56 };
57 
58 static unsigned int tdk_read(struct qemu_phy *phy, unsigned int req)
59 {
60     int regnum;
61     unsigned r = 0;
62 
63     regnum = req & 0x1f;
64 
65     switch (regnum) {
66     case 1:
67         if (!phy->link) {
68             break;
69         }
70         /* MR1.     */
71         /* Speeds and modes.  */
72         r |= (1 << 13) | (1 << 14);
73         r |= (1 << 11) | (1 << 12);
74         r |= (1 << 5); /* Autoneg complete.  */
75         r |= (1 << 3); /* Autoneg able.     */
76         r |= (1 << 2); /* link.     */
77         break;
78     case 5:
79         /* Link partner ability.
80            We are kind; always agree with whatever best mode
81            the guest advertises.  */
82         r = 1 << 14; /* Success.  */
83         /* Copy advertised modes.  */
84         r |= phy->regs[4] & (15 << 5);
85         /* Autoneg support.  */
86         r |= 1;
87         break;
88     case 18:
89     {
90         /* Diagnostics reg.  */
91         int duplex = 0;
92         int speed_100 = 0;
93 
94         if (!phy->link) {
95             break;
96         }
97 
98         /* Are we advertising 100 half or 100 duplex ? */
99         speed_100 = !!(phy->regs[4] & ADVERTISE_100HALF);
100         speed_100 |= !!(phy->regs[4] & ADVERTISE_100FULL);
101 
102         /* Are we advertising 10 duplex or 100 duplex ? */
103         duplex = !!(phy->regs[4] & ADVERTISE_100FULL);
104         duplex |= !!(phy->regs[4] & ADVERTISE_10FULL);
105         r = (speed_100 << 10) | (duplex << 11);
106     }
107     break;
108 
109     default:
110         r = phy->regs[regnum];
111         break;
112     }
113     trace_mdio_phy_read(regnum, r);
114     return r;
115 }
116 
117 static void
118 tdk_write(struct qemu_phy *phy, unsigned int req, unsigned int data)
119 {
120     int regnum;
121 
122     regnum = req & 0x1f;
123     trace_mdio_phy_write(regnum, data);
124     switch (regnum) {
125     default:
126         phy->regs[regnum] = data;
127         break;
128     }
129 }
130 
131 static void
132 tdk_reset(struct qemu_phy *phy)
133 {
134     phy->regs[0] = 0x3100;
135     /* PHY Id.  */
136     phy->regs[2] = 0x0300;
137     phy->regs[3] = 0xe400;
138     /* Autonegotiation advertisement reg.  */
139     phy->regs[4] = 0x01E1;
140     phy->link = 1;
141 }
142 
143 struct qemu_mdio
144 {
145     /* bus.     */
146     int mdc;
147     int mdio;
148 
149     /* decoder.  */
150     enum {
151         PREAMBLE,
152         SOF,
153         OPC,
154         ADDR,
155         REQ,
156         TURNAROUND,
157         DATA
158     } state;
159     unsigned int drive;
160 
161     unsigned int cnt;
162     unsigned int addr;
163     unsigned int opc;
164     unsigned int req;
165     unsigned int data;
166 
167     struct qemu_phy *devs[32];
168 };
169 
170 static void
171 mdio_attach(struct qemu_mdio *bus, struct qemu_phy *phy, unsigned int addr)
172 {
173     bus->devs[addr & 0x1f] = phy;
174 }
175 
176 #ifdef USE_THIS_DEAD_CODE
177 static void
178 mdio_detach(struct qemu_mdio *bus, struct qemu_phy *phy, unsigned int addr)
179 {
180     bus->devs[addr & 0x1f] = NULL;
181 }
182 #endif
183 
184 static void mdio_read_req(struct qemu_mdio *bus)
185 {
186     struct qemu_phy *phy;
187 
188     phy = bus->devs[bus->addr];
189     if (phy && phy->read) {
190         bus->data = phy->read(phy, bus->req);
191     } else {
192         bus->data = 0xffff;
193     }
194 }
195 
196 static void mdio_write_req(struct qemu_mdio *bus)
197 {
198     struct qemu_phy *phy;
199 
200     phy = bus->devs[bus->addr];
201     if (phy && phy->write) {
202         phy->write(phy, bus->req, bus->data);
203     }
204 }
205 
206 static void mdio_cycle(struct qemu_mdio *bus)
207 {
208     bus->cnt++;
209 
210     trace_mdio_bitbang(bus->mdc, bus->mdio, bus->state, bus->cnt, bus->drive);
211 #if 0
212     if (bus->mdc) {
213         printf("%d", bus->mdio);
214     }
215 #endif
216     switch (bus->state) {
217     case PREAMBLE:
218         if (bus->mdc) {
219             if (bus->cnt >= (32 * 2) && !bus->mdio) {
220                 bus->cnt = 0;
221                 bus->state = SOF;
222                 bus->data = 0;
223             }
224         }
225         break;
226     case SOF:
227         if (bus->mdc) {
228             if (bus->mdio != 1) {
229                 printf("WARNING: no SOF\n");
230             }
231             if (bus->cnt == 1*2) {
232                 bus->cnt = 0;
233                 bus->opc = 0;
234                 bus->state = OPC;
235             }
236         }
237         break;
238     case OPC:
239         if (bus->mdc) {
240             bus->opc <<= 1;
241             bus->opc |= bus->mdio & 1;
242             if (bus->cnt == 2*2) {
243                 bus->cnt = 0;
244                 bus->addr = 0;
245                 bus->state = ADDR;
246             }
247         }
248         break;
249     case ADDR:
250         if (bus->mdc) {
251             bus->addr <<= 1;
252             bus->addr |= bus->mdio & 1;
253 
254             if (bus->cnt == 5*2) {
255                 bus->cnt = 0;
256                 bus->req = 0;
257                 bus->state = REQ;
258             }
259         }
260         break;
261     case REQ:
262         if (bus->mdc) {
263             bus->req <<= 1;
264             bus->req |= bus->mdio & 1;
265             if (bus->cnt == 5*2) {
266                 bus->cnt = 0;
267                 bus->state = TURNAROUND;
268             }
269         }
270         break;
271     case TURNAROUND:
272         if (bus->mdc && bus->cnt == 2*2) {
273             bus->mdio = 0;
274             bus->cnt = 0;
275 
276             if (bus->opc == 2) {
277                 bus->drive = 1;
278                 mdio_read_req(bus);
279                 bus->mdio = bus->data & 1;
280             }
281             bus->state = DATA;
282         }
283         break;
284     case DATA:
285         if (!bus->mdc) {
286             if (bus->drive) {
287                 bus->mdio = !!(bus->data & (1 << 15));
288                 bus->data <<= 1;
289             }
290         } else {
291             if (!bus->drive) {
292                 bus->data <<= 1;
293                 bus->data |= bus->mdio;
294             }
295             if (bus->cnt == 16 * 2) {
296                 bus->cnt = 0;
297                 bus->state = PREAMBLE;
298                 if (!bus->drive) {
299                     mdio_write_req(bus);
300                 }
301                 bus->drive = 0;
302             }
303         }
304         break;
305     default:
306         break;
307     }
308 }
309 
310 /* ETRAX-FS Ethernet MAC block starts here.  */
311 
312 #define RW_MA0_LO      0x00
313 #define RW_MA0_HI      0x01
314 #define RW_MA1_LO      0x02
315 #define RW_MA1_HI      0x03
316 #define RW_GA_LO      0x04
317 #define RW_GA_HI      0x05
318 #define RW_GEN_CTRL      0x06
319 #define RW_REC_CTRL      0x07
320 #define RW_TR_CTRL      0x08
321 #define RW_CLR_ERR      0x09
322 #define RW_MGM_CTRL      0x0a
323 #define R_STAT          0x0b
324 #define FS_ETH_MAX_REGS      0x17
325 
326 #define TYPE_ETRAX_FS_ETH "etraxfs-eth"
327 OBJECT_DECLARE_SIMPLE_TYPE(ETRAXFSEthState, ETRAX_FS_ETH)
328 
329 struct ETRAXFSEthState {
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     struct etraxfs_dma_client *dma_out;
341     struct etraxfs_dma_client *dma_in;
342 
343     /* MDIO bus.  */
344     struct qemu_mdio mdio_bus;
345     unsigned int phyaddr;
346     int duplex_mismatch;
347 
348     /* PHY.     */
349     struct qemu_phy phy;
350 };
351 
352 static void eth_validate_duplex(ETRAXFSEthState *eth)
353 {
354     struct qemu_phy *phy;
355     unsigned int phy_duplex;
356     unsigned int mac_duplex;
357     int new_mm = 0;
358 
359     phy = eth->mdio_bus.devs[eth->phyaddr];
360     phy_duplex = !!(phy->read(phy, 18) & (1 << 11));
361     mac_duplex = !!(eth->regs[RW_REC_CTRL] & 128);
362 
363     if (mac_duplex != phy_duplex) {
364         new_mm = 1;
365     }
366 
367     if (eth->regs[RW_GEN_CTRL] & 1) {
368         if (new_mm != eth->duplex_mismatch) {
369             if (new_mm) {
370                 printf("HW: WARNING ETH duplex mismatch MAC=%d PHY=%d\n",
371                        mac_duplex, phy_duplex);
372             } else {
373                 printf("HW: ETH duplex ok.\n");
374             }
375         }
376         eth->duplex_mismatch = new_mm;
377     }
378 }
379 
380 static uint64_t
381 eth_read(void *opaque, hwaddr addr, unsigned int size)
382 {
383     ETRAXFSEthState *eth = opaque;
384     uint32_t r = 0;
385 
386     addr >>= 2;
387 
388     switch (addr) {
389     case R_STAT:
390         r = eth->mdio_bus.mdio & 1;
391         break;
392     default:
393         r = eth->regs[addr];
394         D(printf("%s %x\n", __func__, addr * 4));
395         break;
396     }
397     return r;
398 }
399 
400 static void eth_update_ma(ETRAXFSEthState *eth, int ma)
401 {
402     int reg;
403     int i = 0;
404 
405     ma &= 1;
406 
407     reg = RW_MA0_LO;
408     if (ma) {
409         reg = RW_MA1_LO;
410     }
411 
412     eth->macaddr[ma][i++] = eth->regs[reg];
413     eth->macaddr[ma][i++] = eth->regs[reg] >> 8;
414     eth->macaddr[ma][i++] = eth->regs[reg] >> 16;
415     eth->macaddr[ma][i++] = eth->regs[reg] >> 24;
416     eth->macaddr[ma][i++] = eth->regs[reg + 1];
417     eth->macaddr[ma][i] = eth->regs[reg + 1] >> 8;
418 
419     D(printf("set mac%d=%x.%x.%x.%x.%x.%x\n", ma,
420              eth->macaddr[ma][0], eth->macaddr[ma][1],
421              eth->macaddr[ma][2], eth->macaddr[ma][3],
422              eth->macaddr[ma][4], eth->macaddr[ma][5]));
423 }
424 
425 static void
426 eth_write(void *opaque, hwaddr addr,
427           uint64_t val64, unsigned int size)
428 {
429     ETRAXFSEthState *eth = opaque;
430     uint32_t value = val64;
431 
432     addr >>= 2;
433     switch (addr) {
434     case RW_MA0_LO:
435     case RW_MA0_HI:
436         eth->regs[addr] = value;
437         eth_update_ma(eth, 0);
438         break;
439     case RW_MA1_LO:
440     case RW_MA1_HI:
441         eth->regs[addr] = value;
442         eth_update_ma(eth, 1);
443         break;
444 
445     case RW_MGM_CTRL:
446         /* Attach an MDIO/PHY abstraction.  */
447         if (value & 2) {
448             eth->mdio_bus.mdio = value & 1;
449         }
450         if (eth->mdio_bus.mdc != (value & 4)) {
451             mdio_cycle(&eth->mdio_bus);
452             eth_validate_duplex(eth);
453         }
454         eth->mdio_bus.mdc = !!(value & 4);
455         eth->regs[addr] = value;
456         break;
457 
458     case RW_REC_CTRL:
459         eth->regs[addr] = value;
460         eth_validate_duplex(eth);
461         break;
462 
463     default:
464         eth->regs[addr] = value;
465         D(printf("%s %x %x\n", __func__, addr, value));
466         break;
467     }
468 }
469 
470 /* The ETRAX FS has a groupt address table (GAT) which works like a k=1 bloom
471    filter dropping group addresses we have not joined.    The filter has 64
472    bits (m). The has function is a simple nible xor of the group addr.    */
473 static int eth_match_groupaddr(ETRAXFSEthState *eth, const unsigned char *sa)
474 {
475     unsigned int hsh;
476     int m_individual = eth->regs[RW_REC_CTRL] & 4;
477     int match;
478 
479     /* First bit on the wire of a MAC address signals multicast or
480        physical address.  */
481     if (!m_individual && !(sa[0] & 1)) {
482         return 0;
483     }
484 
485     /* Calculate the hash index for the GA registers. */
486     hsh = 0;
487     hsh ^= (*sa) & 0x3f;
488     hsh ^= ((*sa) >> 6) & 0x03;
489     ++sa;
490     hsh ^= ((*sa) << 2) & 0x03c;
491     hsh ^= ((*sa) >> 4) & 0xf;
492     ++sa;
493     hsh ^= ((*sa) << 4) & 0x30;
494     hsh ^= ((*sa) >> 2) & 0x3f;
495     ++sa;
496     hsh ^= (*sa) & 0x3f;
497     hsh ^= ((*sa) >> 6) & 0x03;
498     ++sa;
499     hsh ^= ((*sa) << 2) & 0x03c;
500     hsh ^= ((*sa) >> 4) & 0xf;
501     ++sa;
502     hsh ^= ((*sa) << 4) & 0x30;
503     hsh ^= ((*sa) >> 2) & 0x3f;
504 
505     hsh &= 63;
506     if (hsh > 31) {
507         match = eth->regs[RW_GA_HI] & (1 << (hsh - 32));
508     } else {
509         match = eth->regs[RW_GA_LO] & (1 << hsh);
510     }
511     D(printf("hsh=%x ga=%x.%x mtch=%d\n", hsh,
512              eth->regs[RW_GA_HI], eth->regs[RW_GA_LO], match));
513     return match;
514 }
515 
516 static ssize_t eth_receive(NetClientState *nc, const uint8_t *buf, size_t size)
517 {
518     unsigned char sa_bcast[6] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
519     ETRAXFSEthState *eth = qemu_get_nic_opaque(nc);
520     int use_ma0 = eth->regs[RW_REC_CTRL] & 1;
521     int use_ma1 = eth->regs[RW_REC_CTRL] & 2;
522     int r_bcast = eth->regs[RW_REC_CTRL] & 8;
523 
524     if (size < 12) {
525         return -1;
526     }
527 
528     D(printf("%x.%x.%x.%x.%x.%x ma=%d %d bc=%d\n",
529          buf[0], buf[1], buf[2], buf[3], buf[4], buf[5],
530          use_ma0, use_ma1, r_bcast));
531 
532     /* Does the frame get through the address filters?  */
533     if ((!use_ma0 || memcmp(buf, eth->macaddr[0], 6))
534         && (!use_ma1 || memcmp(buf, eth->macaddr[1], 6))
535         && (!r_bcast || memcmp(buf, sa_bcast, 6))
536         && !eth_match_groupaddr(eth, buf)) {
537         return size;
538     }
539 
540     /* FIXME: Find another way to pass on the fake csum.  */
541     etraxfs_dmac_input(eth->dma_in, (void *)buf, size + 4, 1);
542 
543     return size;
544 }
545 
546 static int eth_tx_push(void *opaque, unsigned char *buf, int len, bool eop)
547 {
548     ETRAXFSEthState *eth = opaque;
549 
550     D(printf("%s buf=%p len=%d\n", __func__, buf, len));
551     qemu_send_packet(qemu_get_queue(eth->nic), buf, len);
552     return len;
553 }
554 
555 static void eth_set_link(NetClientState *nc)
556 {
557     ETRAXFSEthState *eth = qemu_get_nic_opaque(nc);
558     D(printf("%s %d\n", __func__, nc->link_down));
559     eth->phy.link = !nc->link_down;
560 }
561 
562 static const MemoryRegionOps eth_ops = {
563     .read = eth_read,
564     .write = eth_write,
565     .endianness = DEVICE_LITTLE_ENDIAN,
566     .valid = {
567         .min_access_size = 4,
568         .max_access_size = 4
569     }
570 };
571 
572 static NetClientInfo net_etraxfs_info = {
573     .type = NET_CLIENT_DRIVER_NIC,
574     .size = sizeof(NICState),
575     .receive = eth_receive,
576     .link_status_changed = eth_set_link,
577 };
578 
579 static void etraxfs_eth_reset(DeviceState *dev)
580 {
581     ETRAXFSEthState *s = ETRAX_FS_ETH(dev);
582 
583     memset(s->regs, 0, sizeof(s->regs));
584     memset(s->macaddr, 0, sizeof(s->macaddr));
585     s->duplex_mismatch = 0;
586 
587     s->mdio_bus.mdc = 0;
588     s->mdio_bus.mdio = 0;
589     s->mdio_bus.state = 0;
590     s->mdio_bus.drive = 0;
591     s->mdio_bus.cnt = 0;
592     s->mdio_bus.addr = 0;
593     s->mdio_bus.opc = 0;
594     s->mdio_bus.req = 0;
595     s->mdio_bus.data = 0;
596 
597     tdk_reset(&s->phy);
598 }
599 
600 static void etraxfs_eth_realize(DeviceState *dev, Error **errp)
601 {
602     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
603     ETRAXFSEthState *s = ETRAX_FS_ETH(dev);
604 
605     if (!s->dma_out || !s->dma_in) {
606         error_setg(errp, "Unconnected ETRAX-FS Ethernet MAC");
607         return;
608     }
609 
610     s->dma_out->client.push = eth_tx_push;
611     s->dma_out->client.opaque = s;
612     s->dma_in->client.opaque = s;
613     s->dma_in->client.pull = NULL;
614 
615     memory_region_init_io(&s->mmio, OBJECT(dev), &eth_ops, s,
616                           "etraxfs-eth", 0x5c);
617     sysbus_init_mmio(sbd, &s->mmio);
618 
619     qemu_macaddr_default_if_unset(&s->conf.macaddr);
620     s->nic = qemu_new_nic(&net_etraxfs_info, &s->conf,
621                           object_get_typename(OBJECT(s)), dev->id,
622                           &dev->mem_reentrancy_guard, 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     device_class_set_props(dc, 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(hwaddr base, int phyaddr,
651                  struct etraxfs_dma_client *dma_out,
652                  struct etraxfs_dma_client *dma_in)
653 {
654     DeviceState *dev;
655 
656     dev = qdev_new("etraxfs-eth");
657     qemu_configure_nic_device(dev, true, "fseth");
658     qdev_prop_set_uint32(dev, "phyaddr", phyaddr);
659 
660     /*
661      * TODO: QOM design, define a QOM interface for "I am an etraxfs
662      * DMA client" (which replaces the current 'struct
663      * etraxfs_dma_client' ad-hoc interface), implement it on the
664      * ethernet device, and then have QOM link properties on the DMA
665      * controller device so that you can pass the interface
666      * implementations to it.
667      */
668     ETRAX_FS_ETH(dev)->dma_out = dma_out;
669     ETRAX_FS_ETH(dev)->dma_in = dma_in;
670     sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
671     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, base);
672 
673     return dev;
674 }
675 
676 static const TypeInfo etraxfs_eth_info = {
677     .name          = TYPE_ETRAX_FS_ETH,
678     .parent        = TYPE_SYS_BUS_DEVICE,
679     .instance_size = sizeof(ETRAXFSEthState),
680     .class_init    = etraxfs_eth_class_init,
681 };
682 
683 static void etraxfs_eth_register_types(void)
684 {
685     type_register_static(&etraxfs_eth_info);
686 }
687 
688 type_init(etraxfs_eth_register_types)
689