xref: /openbmc/qemu/hw/net/etraxfs_eth.c (revision 2dbb1308)
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 typedef struct ETRAXFSEthState ETRAXFSEthState;
328 DECLARE_INSTANCE_CHECKER(ETRAXFSEthState, ETRAX_FS_ETH,
329                          TYPE_ETRAX_FS_ETH)
330 
331 struct ETRAXFSEthState {
332     SysBusDevice parent_obj;
333 
334     MemoryRegion mmio;
335     NICState *nic;
336     NICConf conf;
337 
338     /* Two addrs in the filter.  */
339     uint8_t macaddr[2][6];
340     uint32_t regs[FS_ETH_MAX_REGS];
341 
342     struct etraxfs_dma_client *dma_out;
343     struct etraxfs_dma_client *dma_in;
344 
345     /* MDIO bus.  */
346     struct qemu_mdio mdio_bus;
347     unsigned int phyaddr;
348     int duplex_mismatch;
349 
350     /* PHY.     */
351     struct qemu_phy phy;
352 };
353 
354 static void eth_validate_duplex(ETRAXFSEthState *eth)
355 {
356     struct qemu_phy *phy;
357     unsigned int phy_duplex;
358     unsigned int mac_duplex;
359     int new_mm = 0;
360 
361     phy = eth->mdio_bus.devs[eth->phyaddr];
362     phy_duplex = !!(phy->read(phy, 18) & (1 << 11));
363     mac_duplex = !!(eth->regs[RW_REC_CTRL] & 128);
364 
365     if (mac_duplex != phy_duplex) {
366         new_mm = 1;
367     }
368 
369     if (eth->regs[RW_GEN_CTRL] & 1) {
370         if (new_mm != eth->duplex_mismatch) {
371             if (new_mm) {
372                 printf("HW: WARNING ETH duplex mismatch MAC=%d PHY=%d\n",
373                        mac_duplex, phy_duplex);
374             } else {
375                 printf("HW: ETH duplex ok.\n");
376             }
377         }
378         eth->duplex_mismatch = new_mm;
379     }
380 }
381 
382 static uint64_t
383 eth_read(void *opaque, hwaddr addr, unsigned int size)
384 {
385     ETRAXFSEthState *eth = opaque;
386     uint32_t r = 0;
387 
388     addr >>= 2;
389 
390     switch (addr) {
391     case R_STAT:
392         r = eth->mdio_bus.mdio & 1;
393         break;
394     default:
395         r = eth->regs[addr];
396         D(printf("%s %x\n", __func__, addr * 4));
397         break;
398     }
399     return r;
400 }
401 
402 static void eth_update_ma(ETRAXFSEthState *eth, int ma)
403 {
404     int reg;
405     int i = 0;
406 
407     ma &= 1;
408 
409     reg = RW_MA0_LO;
410     if (ma) {
411         reg = RW_MA1_LO;
412     }
413 
414     eth->macaddr[ma][i++] = eth->regs[reg];
415     eth->macaddr[ma][i++] = eth->regs[reg] >> 8;
416     eth->macaddr[ma][i++] = eth->regs[reg] >> 16;
417     eth->macaddr[ma][i++] = eth->regs[reg] >> 24;
418     eth->macaddr[ma][i++] = eth->regs[reg + 1];
419     eth->macaddr[ma][i] = eth->regs[reg + 1] >> 8;
420 
421     D(printf("set mac%d=%x.%x.%x.%x.%x.%x\n", ma,
422              eth->macaddr[ma][0], eth->macaddr[ma][1],
423              eth->macaddr[ma][2], eth->macaddr[ma][3],
424              eth->macaddr[ma][4], eth->macaddr[ma][5]));
425 }
426 
427 static void
428 eth_write(void *opaque, hwaddr addr,
429           uint64_t val64, unsigned int size)
430 {
431     ETRAXFSEthState *eth = opaque;
432     uint32_t value = val64;
433 
434     addr >>= 2;
435     switch (addr) {
436     case RW_MA0_LO:
437     case RW_MA0_HI:
438         eth->regs[addr] = value;
439         eth_update_ma(eth, 0);
440         break;
441     case RW_MA1_LO:
442     case RW_MA1_HI:
443         eth->regs[addr] = value;
444         eth_update_ma(eth, 1);
445         break;
446 
447     case RW_MGM_CTRL:
448         /* Attach an MDIO/PHY abstraction.  */
449         if (value & 2) {
450             eth->mdio_bus.mdio = value & 1;
451         }
452         if (eth->mdio_bus.mdc != (value & 4)) {
453             mdio_cycle(&eth->mdio_bus);
454             eth_validate_duplex(eth);
455         }
456         eth->mdio_bus.mdc = !!(value & 4);
457         eth->regs[addr] = value;
458         break;
459 
460     case RW_REC_CTRL:
461         eth->regs[addr] = value;
462         eth_validate_duplex(eth);
463         break;
464 
465     default:
466         eth->regs[addr] = value;
467         D(printf("%s %x %x\n", __func__, addr, value));
468         break;
469     }
470 }
471 
472 /* The ETRAX FS has a groupt address table (GAT) which works like a k=1 bloom
473    filter dropping group addresses we have not joined.    The filter has 64
474    bits (m). The has function is a simple nible xor of the group addr.    */
475 static int eth_match_groupaddr(ETRAXFSEthState *eth, const unsigned char *sa)
476 {
477     unsigned int hsh;
478     int m_individual = eth->regs[RW_REC_CTRL] & 4;
479     int match;
480 
481     /* First bit on the wire of a MAC address signals multicast or
482        physical address.  */
483     if (!m_individual && !(sa[0] & 1)) {
484         return 0;
485     }
486 
487     /* Calculate the hash index for the GA registers. */
488     hsh = 0;
489     hsh ^= (*sa) & 0x3f;
490     hsh ^= ((*sa) >> 6) & 0x03;
491     ++sa;
492     hsh ^= ((*sa) << 2) & 0x03c;
493     hsh ^= ((*sa) >> 4) & 0xf;
494     ++sa;
495     hsh ^= ((*sa) << 4) & 0x30;
496     hsh ^= ((*sa) >> 2) & 0x3f;
497     ++sa;
498     hsh ^= (*sa) & 0x3f;
499     hsh ^= ((*sa) >> 6) & 0x03;
500     ++sa;
501     hsh ^= ((*sa) << 2) & 0x03c;
502     hsh ^= ((*sa) >> 4) & 0xf;
503     ++sa;
504     hsh ^= ((*sa) << 4) & 0x30;
505     hsh ^= ((*sa) >> 2) & 0x3f;
506 
507     hsh &= 63;
508     if (hsh > 31) {
509         match = eth->regs[RW_GA_HI] & (1 << (hsh - 32));
510     } else {
511         match = eth->regs[RW_GA_LO] & (1 << hsh);
512     }
513     D(printf("hsh=%x ga=%x.%x mtch=%d\n", hsh,
514              eth->regs[RW_GA_HI], eth->regs[RW_GA_LO], match));
515     return match;
516 }
517 
518 static ssize_t eth_receive(NetClientState *nc, const uint8_t *buf, size_t size)
519 {
520     unsigned char sa_bcast[6] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
521     ETRAXFSEthState *eth = qemu_get_nic_opaque(nc);
522     int use_ma0 = eth->regs[RW_REC_CTRL] & 1;
523     int use_ma1 = eth->regs[RW_REC_CTRL] & 2;
524     int r_bcast = eth->regs[RW_REC_CTRL] & 8;
525 
526     if (size < 12) {
527         return -1;
528     }
529 
530     D(printf("%x.%x.%x.%x.%x.%x ma=%d %d bc=%d\n",
531          buf[0], buf[1], buf[2], buf[3], buf[4], buf[5],
532          use_ma0, use_ma1, r_bcast));
533 
534     /* Does the frame get through the address filters?  */
535     if ((!use_ma0 || memcmp(buf, eth->macaddr[0], 6))
536         && (!use_ma1 || memcmp(buf, eth->macaddr[1], 6))
537         && (!r_bcast || memcmp(buf, sa_bcast, 6))
538         && !eth_match_groupaddr(eth, buf)) {
539         return size;
540     }
541 
542     /* FIXME: Find another way to pass on the fake csum.  */
543     etraxfs_dmac_input(eth->dma_in, (void *)buf, size + 4, 1);
544 
545     return size;
546 }
547 
548 static int eth_tx_push(void *opaque, unsigned char *buf, int len, bool eop)
549 {
550     ETRAXFSEthState *eth = opaque;
551 
552     D(printf("%s buf=%p len=%d\n", __func__, buf, len));
553     qemu_send_packet(qemu_get_queue(eth->nic), buf, len);
554     return len;
555 }
556 
557 static void eth_set_link(NetClientState *nc)
558 {
559     ETRAXFSEthState *eth = qemu_get_nic_opaque(nc);
560     D(printf("%s %d\n", __func__, nc->link_down));
561     eth->phy.link = !nc->link_down;
562 }
563 
564 static const MemoryRegionOps eth_ops = {
565     .read = eth_read,
566     .write = eth_write,
567     .endianness = DEVICE_LITTLE_ENDIAN,
568     .valid = {
569         .min_access_size = 4,
570         .max_access_size = 4
571     }
572 };
573 
574 static NetClientInfo net_etraxfs_info = {
575     .type = NET_CLIENT_DRIVER_NIC,
576     .size = sizeof(NICState),
577     .receive = eth_receive,
578     .link_status_changed = eth_set_link,
579 };
580 
581 static void etraxfs_eth_reset(DeviceState *dev)
582 {
583     ETRAXFSEthState *s = ETRAX_FS_ETH(dev);
584 
585     memset(s->regs, 0, sizeof(s->regs));
586     memset(s->macaddr, 0, sizeof(s->macaddr));
587     s->duplex_mismatch = 0;
588 
589     s->mdio_bus.mdc = 0;
590     s->mdio_bus.mdio = 0;
591     s->mdio_bus.state = 0;
592     s->mdio_bus.drive = 0;
593     s->mdio_bus.cnt = 0;
594     s->mdio_bus.addr = 0;
595     s->mdio_bus.opc = 0;
596     s->mdio_bus.req = 0;
597     s->mdio_bus.data = 0;
598 
599     tdk_reset(&s->phy);
600 }
601 
602 static void etraxfs_eth_realize(DeviceState *dev, Error **errp)
603 {
604     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
605     ETRAXFSEthState *s = ETRAX_FS_ETH(dev);
606 
607     if (!s->dma_out || !s->dma_in) {
608         error_setg(errp, "Unconnected ETRAX-FS Ethernet MAC");
609         return;
610     }
611 
612     s->dma_out->client.push = eth_tx_push;
613     s->dma_out->client.opaque = s;
614     s->dma_in->client.opaque = s;
615     s->dma_in->client.pull = NULL;
616 
617     memory_region_init_io(&s->mmio, OBJECT(dev), &eth_ops, s,
618                           "etraxfs-eth", 0x5c);
619     sysbus_init_mmio(sbd, &s->mmio);
620 
621     qemu_macaddr_default_if_unset(&s->conf.macaddr);
622     s->nic = qemu_new_nic(&net_etraxfs_info, &s->conf,
623                           object_get_typename(OBJECT(s)), dev->id, s);
624     qemu_format_nic_info_str(qemu_get_queue(s->nic), s->conf.macaddr.a);
625 
626     s->phy.read = tdk_read;
627     s->phy.write = tdk_write;
628     mdio_attach(&s->mdio_bus, &s->phy, s->phyaddr);
629 }
630 
631 static Property etraxfs_eth_properties[] = {
632     DEFINE_PROP_UINT32("phyaddr", ETRAXFSEthState, phyaddr, 1),
633     DEFINE_NIC_PROPERTIES(ETRAXFSEthState, conf),
634     DEFINE_PROP_END_OF_LIST(),
635 };
636 
637 static void etraxfs_eth_class_init(ObjectClass *klass, void *data)
638 {
639     DeviceClass *dc = DEVICE_CLASS(klass);
640 
641     dc->realize = etraxfs_eth_realize;
642     dc->reset = etraxfs_eth_reset;
643     device_class_set_props(dc, etraxfs_eth_properties);
644     /* Reason: dma_out, dma_in are not user settable */
645     dc->user_creatable = false;
646 }
647 
648 
649 /* Instantiate an ETRAXFS Ethernet MAC.  */
650 DeviceState *
651 etraxfs_eth_init(NICInfo *nd, hwaddr base, int phyaddr,
652                  struct etraxfs_dma_client *dma_out,
653                  struct etraxfs_dma_client *dma_in)
654 {
655     DeviceState *dev;
656     qemu_check_nic_model(nd, "fseth");
657 
658     dev = qdev_new("etraxfs-eth");
659     qdev_set_nic_properties(dev, nd);
660     qdev_prop_set_uint32(dev, "phyaddr", phyaddr);
661 
662     /*
663      * TODO: QOM design, define a QOM interface for "I am an etraxfs
664      * DMA client" (which replaces the current 'struct
665      * etraxfs_dma_client' ad-hoc interface), implement it on the
666      * ethernet device, and then have QOM link properties on the DMA
667      * controller device so that you can pass the interface
668      * implementations to it.
669      */
670     ETRAX_FS_ETH(dev)->dma_out = dma_out;
671     ETRAX_FS_ETH(dev)->dma_in = dma_in;
672     sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
673     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, base);
674 
675     return dev;
676 }
677 
678 static const TypeInfo etraxfs_eth_info = {
679     .name          = TYPE_ETRAX_FS_ETH,
680     .parent        = TYPE_SYS_BUS_DEVICE,
681     .instance_size = sizeof(ETRAXFSEthState),
682     .class_init    = etraxfs_eth_class_init,
683 };
684 
685 static void etraxfs_eth_register_types(void)
686 {
687     type_register_static(&etraxfs_eth_info);
688 }
689 
690 type_init(etraxfs_eth_register_types)
691