xref: /openbmc/qemu/hw/net/allwinner-sun8i-emac.c (revision 5e437d3c)
1 /*
2  * Allwinner Sun8i Ethernet MAC emulation
3  *
4  * Copyright (C) 2019 Niek Linnenbank <nieklinnenbank@gmail.com>
5  *
6  * This program is free software: you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation, either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include "qemu/osdep.h"
21 #include "qemu/units.h"
22 #include "qapi/error.h"
23 #include "hw/sysbus.h"
24 #include "migration/vmstate.h"
25 #include "net/net.h"
26 #include "hw/irq.h"
27 #include "hw/qdev-properties.h"
28 #include "qemu/log.h"
29 #include "trace.h"
30 #include "net/checksum.h"
31 #include "qemu/module.h"
32 #include "exec/cpu-common.h"
33 #include "sysemu/dma.h"
34 #include "hw/net/allwinner-sun8i-emac.h"
35 
36 /* EMAC register offsets */
37 enum {
38     REG_BASIC_CTL_0        = 0x0000, /* Basic Control 0 */
39     REG_BASIC_CTL_1        = 0x0004, /* Basic Control 1 */
40     REG_INT_STA            = 0x0008, /* Interrupt Status */
41     REG_INT_EN             = 0x000C, /* Interrupt Enable */
42     REG_TX_CTL_0           = 0x0010, /* Transmit Control 0 */
43     REG_TX_CTL_1           = 0x0014, /* Transmit Control 1 */
44     REG_TX_FLOW_CTL        = 0x001C, /* Transmit Flow Control */
45     REG_TX_DMA_DESC_LIST   = 0x0020, /* Transmit Descriptor List Address */
46     REG_RX_CTL_0           = 0x0024, /* Receive Control 0 */
47     REG_RX_CTL_1           = 0x0028, /* Receive Control 1 */
48     REG_RX_DMA_DESC_LIST   = 0x0034, /* Receive Descriptor List Address */
49     REG_FRM_FLT            = 0x0038, /* Receive Frame Filter */
50     REG_RX_HASH_0          = 0x0040, /* Receive Hash Table 0 */
51     REG_RX_HASH_1          = 0x0044, /* Receive Hash Table 1 */
52     REG_MII_CMD            = 0x0048, /* Management Interface Command */
53     REG_MII_DATA           = 0x004C, /* Management Interface Data */
54     REG_ADDR_HIGH          = 0x0050, /* MAC Address High */
55     REG_ADDR_LOW           = 0x0054, /* MAC Address Low */
56     REG_TX_DMA_STA         = 0x00B0, /* Transmit DMA Status */
57     REG_TX_CUR_DESC        = 0x00B4, /* Transmit Current Descriptor */
58     REG_TX_CUR_BUF         = 0x00B8, /* Transmit Current Buffer */
59     REG_RX_DMA_STA         = 0x00C0, /* Receive DMA Status */
60     REG_RX_CUR_DESC        = 0x00C4, /* Receive Current Descriptor */
61     REG_RX_CUR_BUF         = 0x00C8, /* Receive Current Buffer */
62     REG_RGMII_STA          = 0x00D0, /* RGMII Status */
63 };
64 
65 /* EMAC register flags */
66 enum {
67     BASIC_CTL0_100Mbps     = (0b11 << 2),
68     BASIC_CTL0_FD          = (1 << 0),
69     BASIC_CTL1_SOFTRST     = (1 << 0),
70 };
71 
72 enum {
73     INT_STA_RGMII_LINK     = (1 << 16),
74     INT_STA_RX_EARLY       = (1 << 13),
75     INT_STA_RX_OVERFLOW    = (1 << 12),
76     INT_STA_RX_TIMEOUT     = (1 << 11),
77     INT_STA_RX_DMA_STOP    = (1 << 10),
78     INT_STA_RX_BUF_UA      = (1 << 9),
79     INT_STA_RX             = (1 << 8),
80     INT_STA_TX_EARLY       = (1 << 5),
81     INT_STA_TX_UNDERFLOW   = (1 << 4),
82     INT_STA_TX_TIMEOUT     = (1 << 3),
83     INT_STA_TX_BUF_UA      = (1 << 2),
84     INT_STA_TX_DMA_STOP    = (1 << 1),
85     INT_STA_TX             = (1 << 0),
86 };
87 
88 enum {
89     INT_EN_RX_EARLY        = (1 << 13),
90     INT_EN_RX_OVERFLOW     = (1 << 12),
91     INT_EN_RX_TIMEOUT      = (1 << 11),
92     INT_EN_RX_DMA_STOP     = (1 << 10),
93     INT_EN_RX_BUF_UA       = (1 << 9),
94     INT_EN_RX              = (1 << 8),
95     INT_EN_TX_EARLY        = (1 << 5),
96     INT_EN_TX_UNDERFLOW    = (1 << 4),
97     INT_EN_TX_TIMEOUT      = (1 << 3),
98     INT_EN_TX_BUF_UA       = (1 << 2),
99     INT_EN_TX_DMA_STOP     = (1 << 1),
100     INT_EN_TX              = (1 << 0),
101 };
102 
103 enum {
104     TX_CTL0_TX_EN          = (1 << 31),
105     TX_CTL1_TX_DMA_START   = (1 << 31),
106     TX_CTL1_TX_DMA_EN      = (1 << 30),
107     TX_CTL1_TX_FLUSH       = (1 << 0),
108 };
109 
110 enum {
111     RX_CTL0_RX_EN          = (1 << 31),
112     RX_CTL0_STRIP_FCS      = (1 << 28),
113     RX_CTL0_CRC_IPV4       = (1 << 27),
114 };
115 
116 enum {
117     RX_CTL1_RX_DMA_START   = (1 << 31),
118     RX_CTL1_RX_DMA_EN      = (1 << 30),
119     RX_CTL1_RX_MD          = (1 << 1),
120 };
121 
122 enum {
123     RX_FRM_FLT_DIS_ADDR    = (1 << 31),
124 };
125 
126 enum {
127     MII_CMD_PHY_ADDR_SHIFT = (12),
128     MII_CMD_PHY_ADDR_MASK  = (0xf000),
129     MII_CMD_PHY_REG_SHIFT  = (4),
130     MII_CMD_PHY_REG_MASK   = (0xf0),
131     MII_CMD_PHY_RW         = (1 << 1),
132     MII_CMD_PHY_BUSY       = (1 << 0),
133 };
134 
135 enum {
136     TX_DMA_STA_STOP        = (0b000),
137     TX_DMA_STA_RUN_FETCH   = (0b001),
138     TX_DMA_STA_WAIT_STA    = (0b010),
139 };
140 
141 enum {
142     RX_DMA_STA_STOP        = (0b000),
143     RX_DMA_STA_RUN_FETCH   = (0b001),
144     RX_DMA_STA_WAIT_FRM    = (0b011),
145 };
146 
147 /* EMAC register reset values */
148 enum {
149     REG_BASIC_CTL_1_RST    = 0x08000000,
150 };
151 
152 /* EMAC constants */
153 enum {
154     AW_SUN8I_EMAC_MIN_PKT_SZ  = 64
155 };
156 
157 /* Transmit/receive frame descriptor */
158 typedef struct FrameDescriptor {
159     uint32_t status;
160     uint32_t status2;
161     uint32_t addr;
162     uint32_t next;
163 } FrameDescriptor;
164 
165 /* Frame descriptor flags */
166 enum {
167     DESC_STATUS_CTL                 = (1 << 31),
168     DESC_STATUS2_BUF_SIZE_MASK      = (0x7ff),
169 };
170 
171 /* Transmit frame descriptor flags */
172 enum {
173     TX_DESC_STATUS_LENGTH_ERR       = (1 << 14),
174     TX_DESC_STATUS2_FIRST_DESC      = (1 << 29),
175     TX_DESC_STATUS2_LAST_DESC       = (1 << 30),
176     TX_DESC_STATUS2_CHECKSUM_MASK   = (0x3 << 27),
177 };
178 
179 /* Receive frame descriptor flags */
180 enum {
181     RX_DESC_STATUS_FIRST_DESC       = (1 << 9),
182     RX_DESC_STATUS_LAST_DESC        = (1 << 8),
183     RX_DESC_STATUS_FRM_LEN_MASK     = (0x3fff0000),
184     RX_DESC_STATUS_FRM_LEN_SHIFT    = (16),
185     RX_DESC_STATUS_NO_BUF           = (1 << 14),
186     RX_DESC_STATUS_HEADER_ERR       = (1 << 7),
187     RX_DESC_STATUS_LENGTH_ERR       = (1 << 4),
188     RX_DESC_STATUS_CRC_ERR          = (1 << 1),
189     RX_DESC_STATUS_PAYLOAD_ERR      = (1 << 0),
190     RX_DESC_STATUS2_RX_INT_CTL      = (1 << 31),
191 };
192 
193 /* MII register offsets */
194 enum {
195     MII_REG_CR                      = (0x0), /* Control */
196     MII_REG_ST                      = (0x1), /* Status */
197     MII_REG_ID_HIGH                 = (0x2), /* Identifier High */
198     MII_REG_ID_LOW                  = (0x3), /* Identifier Low */
199     MII_REG_ADV                     = (0x4), /* Advertised abilities */
200     MII_REG_LPA                     = (0x5), /* Link partner abilities */
201 };
202 
203 /* MII register flags */
204 enum {
205     MII_REG_CR_RESET                = (1 << 15),
206     MII_REG_CR_POWERDOWN            = (1 << 11),
207     MII_REG_CR_10Mbit               = (0),
208     MII_REG_CR_100Mbit              = (1 << 13),
209     MII_REG_CR_1000Mbit             = (1 << 6),
210     MII_REG_CR_AUTO_NEG             = (1 << 12),
211     MII_REG_CR_AUTO_NEG_RESTART     = (1 << 9),
212     MII_REG_CR_FULLDUPLEX           = (1 << 8),
213 };
214 
215 enum {
216     MII_REG_ST_100BASE_T4           = (1 << 15),
217     MII_REG_ST_100BASE_X_FD         = (1 << 14),
218     MII_REG_ST_100BASE_X_HD         = (1 << 13),
219     MII_REG_ST_10_FD                = (1 << 12),
220     MII_REG_ST_10_HD                = (1 << 11),
221     MII_REG_ST_100BASE_T2_FD        = (1 << 10),
222     MII_REG_ST_100BASE_T2_HD        = (1 << 9),
223     MII_REG_ST_AUTONEG_COMPLETE     = (1 << 5),
224     MII_REG_ST_AUTONEG_AVAIL        = (1 << 3),
225     MII_REG_ST_LINK_UP              = (1 << 2),
226 };
227 
228 enum {
229     MII_REG_LPA_10_HD               = (1 << 5),
230     MII_REG_LPA_10_FD               = (1 << 6),
231     MII_REG_LPA_100_HD              = (1 << 7),
232     MII_REG_LPA_100_FD              = (1 << 8),
233     MII_REG_LPA_PAUSE               = (1 << 10),
234     MII_REG_LPA_ASYMPAUSE           = (1 << 11),
235 };
236 
237 /* MII constants */
238 enum {
239     MII_PHY_ID_HIGH                 = 0x0044,
240     MII_PHY_ID_LOW                  = 0x1400,
241 };
242 
243 static void allwinner_sun8i_emac_mii_set_link(AwSun8iEmacState *s,
244                                               bool link_active)
245 {
246     if (link_active) {
247         s->mii_st |= MII_REG_ST_LINK_UP;
248     } else {
249         s->mii_st &= ~MII_REG_ST_LINK_UP;
250     }
251 }
252 
253 static void allwinner_sun8i_emac_mii_reset(AwSun8iEmacState *s,
254                                            bool link_active)
255 {
256     s->mii_cr = MII_REG_CR_100Mbit | MII_REG_CR_AUTO_NEG |
257                 MII_REG_CR_FULLDUPLEX;
258     s->mii_st = MII_REG_ST_100BASE_T4 | MII_REG_ST_100BASE_X_FD |
259                 MII_REG_ST_100BASE_X_HD | MII_REG_ST_10_FD | MII_REG_ST_10_HD |
260                 MII_REG_ST_100BASE_T2_FD | MII_REG_ST_100BASE_T2_HD |
261                 MII_REG_ST_AUTONEG_COMPLETE | MII_REG_ST_AUTONEG_AVAIL;
262     s->mii_adv = 0;
263 
264     allwinner_sun8i_emac_mii_set_link(s, link_active);
265 }
266 
267 static void allwinner_sun8i_emac_mii_cmd(AwSun8iEmacState *s)
268 {
269     uint8_t addr, reg;
270 
271     addr = (s->mii_cmd & MII_CMD_PHY_ADDR_MASK) >> MII_CMD_PHY_ADDR_SHIFT;
272     reg = (s->mii_cmd & MII_CMD_PHY_REG_MASK) >> MII_CMD_PHY_REG_SHIFT;
273 
274     if (addr != s->mii_phy_addr) {
275         return;
276     }
277 
278     /* Read or write a PHY register? */
279     if (s->mii_cmd & MII_CMD_PHY_RW) {
280         trace_allwinner_sun8i_emac_mii_write_reg(reg, s->mii_data);
281 
282         switch (reg) {
283         case MII_REG_CR:
284             if (s->mii_data & MII_REG_CR_RESET) {
285                 allwinner_sun8i_emac_mii_reset(s, s->mii_st &
286                                                   MII_REG_ST_LINK_UP);
287             } else {
288                 s->mii_cr = s->mii_data & ~(MII_REG_CR_RESET |
289                                             MII_REG_CR_AUTO_NEG_RESTART);
290             }
291             break;
292         case MII_REG_ADV:
293             s->mii_adv = s->mii_data;
294             break;
295         case MII_REG_ID_HIGH:
296         case MII_REG_ID_LOW:
297         case MII_REG_LPA:
298             break;
299         default:
300             qemu_log_mask(LOG_UNIMP, "allwinner-h3-emac: write access to "
301                                      "unknown MII register 0x%x\n", reg);
302             break;
303         }
304     } else {
305         switch (reg) {
306         case MII_REG_CR:
307             s->mii_data = s->mii_cr;
308             break;
309         case MII_REG_ST:
310             s->mii_data = s->mii_st;
311             break;
312         case MII_REG_ID_HIGH:
313             s->mii_data = MII_PHY_ID_HIGH;
314             break;
315         case MII_REG_ID_LOW:
316             s->mii_data = MII_PHY_ID_LOW;
317             break;
318         case MII_REG_ADV:
319             s->mii_data = s->mii_adv;
320             break;
321         case MII_REG_LPA:
322             s->mii_data = MII_REG_LPA_10_HD | MII_REG_LPA_10_FD |
323                           MII_REG_LPA_100_HD | MII_REG_LPA_100_FD |
324                           MII_REG_LPA_PAUSE | MII_REG_LPA_ASYMPAUSE;
325             break;
326         default:
327             qemu_log_mask(LOG_UNIMP, "allwinner-h3-emac: read access to "
328                                      "unknown MII register 0x%x\n", reg);
329             s->mii_data = 0;
330             break;
331         }
332 
333         trace_allwinner_sun8i_emac_mii_read_reg(reg, s->mii_data);
334     }
335 }
336 
337 static void allwinner_sun8i_emac_update_irq(AwSun8iEmacState *s)
338 {
339     qemu_set_irq(s->irq, (s->int_sta & s->int_en) != 0);
340 }
341 
342 static bool allwinner_sun8i_emac_desc_owned(FrameDescriptor *desc,
343                                             size_t min_buf_size)
344 {
345     return (desc->status & DESC_STATUS_CTL) && (min_buf_size == 0 ||
346            (desc->status2 & DESC_STATUS2_BUF_SIZE_MASK) >= min_buf_size);
347 }
348 
349 static void allwinner_sun8i_emac_get_desc(AwSun8iEmacState *s,
350                                           FrameDescriptor *desc,
351                                           uint32_t phys_addr)
352 {
353     dma_memory_read(&s->dma_as, phys_addr, desc, sizeof(*desc));
354 }
355 
356 static uint32_t allwinner_sun8i_emac_next_desc(AwSun8iEmacState *s,
357                                                FrameDescriptor *desc)
358 {
359     const uint32_t nxt = desc->next;
360     allwinner_sun8i_emac_get_desc(s, desc, nxt);
361     return nxt;
362 }
363 
364 static uint32_t allwinner_sun8i_emac_find_desc(AwSun8iEmacState *s,
365                                                FrameDescriptor *desc,
366                                                uint32_t start_addr,
367                                                size_t min_size)
368 {
369     uint32_t desc_addr = start_addr;
370 
371     /* Note that the list is a cycle. Last entry points back to the head. */
372     while (desc_addr != 0) {
373         allwinner_sun8i_emac_get_desc(s, desc, desc_addr);
374 
375         if (allwinner_sun8i_emac_desc_owned(desc, min_size)) {
376             return desc_addr;
377         } else if (desc->next == start_addr) {
378             break;
379         } else {
380             desc_addr = desc->next;
381         }
382     }
383 
384     return 0;
385 }
386 
387 static uint32_t allwinner_sun8i_emac_rx_desc(AwSun8iEmacState *s,
388                                              FrameDescriptor *desc,
389                                              size_t min_size)
390 {
391     return allwinner_sun8i_emac_find_desc(s, desc, s->rx_desc_curr, min_size);
392 }
393 
394 static uint32_t allwinner_sun8i_emac_tx_desc(AwSun8iEmacState *s,
395                                              FrameDescriptor *desc)
396 {
397     allwinner_sun8i_emac_get_desc(s, desc, s->tx_desc_curr);
398     return s->tx_desc_curr;
399 }
400 
401 static void allwinner_sun8i_emac_flush_desc(AwSun8iEmacState *s,
402                                             FrameDescriptor *desc,
403                                             uint32_t phys_addr)
404 {
405     dma_memory_write(&s->dma_as, phys_addr, desc, sizeof(*desc));
406 }
407 
408 static bool allwinner_sun8i_emac_can_receive(NetClientState *nc)
409 {
410     AwSun8iEmacState *s = qemu_get_nic_opaque(nc);
411     FrameDescriptor desc;
412 
413     return (s->rx_ctl0 & RX_CTL0_RX_EN) &&
414            (allwinner_sun8i_emac_rx_desc(s, &desc, 0) != 0);
415 }
416 
417 static ssize_t allwinner_sun8i_emac_receive(NetClientState *nc,
418                                             const uint8_t *buf,
419                                             size_t size)
420 {
421     AwSun8iEmacState *s = qemu_get_nic_opaque(nc);
422     FrameDescriptor desc;
423     size_t bytes_left = size;
424     size_t desc_bytes = 0;
425     size_t pad_fcs_size = 4;
426     size_t padding = 0;
427 
428     if (!(s->rx_ctl0 & RX_CTL0_RX_EN)) {
429         return -1;
430     }
431 
432     s->rx_desc_curr = allwinner_sun8i_emac_rx_desc(s, &desc,
433                                                    AW_SUN8I_EMAC_MIN_PKT_SZ);
434     if (!s->rx_desc_curr) {
435         s->int_sta |= INT_STA_RX_BUF_UA;
436     }
437 
438     /* Keep filling RX descriptors until the whole frame is written */
439     while (s->rx_desc_curr && bytes_left > 0) {
440         desc.status &= ~DESC_STATUS_CTL;
441         desc.status &= ~RX_DESC_STATUS_FRM_LEN_MASK;
442 
443         if (bytes_left == size) {
444             desc.status |= RX_DESC_STATUS_FIRST_DESC;
445         }
446 
447         if ((desc.status2 & DESC_STATUS2_BUF_SIZE_MASK) <
448             (bytes_left + pad_fcs_size)) {
449             desc_bytes = desc.status2 & DESC_STATUS2_BUF_SIZE_MASK;
450             desc.status |= desc_bytes << RX_DESC_STATUS_FRM_LEN_SHIFT;
451         } else {
452             padding = pad_fcs_size;
453             if (bytes_left < AW_SUN8I_EMAC_MIN_PKT_SZ) {
454                 padding += (AW_SUN8I_EMAC_MIN_PKT_SZ - bytes_left);
455             }
456 
457             desc_bytes = (bytes_left);
458             desc.status |= RX_DESC_STATUS_LAST_DESC;
459             desc.status |= (bytes_left + padding)
460                             << RX_DESC_STATUS_FRM_LEN_SHIFT;
461         }
462 
463         dma_memory_write(&s->dma_as, desc.addr, buf, desc_bytes);
464         allwinner_sun8i_emac_flush_desc(s, &desc, s->rx_desc_curr);
465         trace_allwinner_sun8i_emac_receive(s->rx_desc_curr, desc.addr,
466                                            desc_bytes);
467 
468         /* Check if frame needs to raise the receive interrupt */
469         if (!(desc.status2 & RX_DESC_STATUS2_RX_INT_CTL)) {
470             s->int_sta |= INT_STA_RX;
471         }
472 
473         /* Increment variables */
474         buf += desc_bytes;
475         bytes_left -= desc_bytes;
476 
477         /* Move to the next descriptor */
478         s->rx_desc_curr = allwinner_sun8i_emac_find_desc(s, &desc, desc.next,
479                                                          AW_SUN8I_EMAC_MIN_PKT_SZ);
480         if (!s->rx_desc_curr) {
481             /* Not enough buffer space available */
482             s->int_sta |= INT_STA_RX_BUF_UA;
483             s->rx_desc_curr = s->rx_desc_head;
484             break;
485         }
486     }
487 
488     /* Report receive DMA is finished */
489     s->rx_ctl1 &= ~RX_CTL1_RX_DMA_START;
490     allwinner_sun8i_emac_update_irq(s);
491 
492     return size;
493 }
494 
495 static void allwinner_sun8i_emac_transmit(AwSun8iEmacState *s)
496 {
497     NetClientState *nc = qemu_get_queue(s->nic);
498     FrameDescriptor desc;
499     size_t bytes = 0;
500     size_t packet_bytes = 0;
501     size_t transmitted = 0;
502     static uint8_t packet_buf[2048];
503 
504     s->tx_desc_curr = allwinner_sun8i_emac_tx_desc(s, &desc);
505 
506     /* Read all transmit descriptors */
507     while (allwinner_sun8i_emac_desc_owned(&desc, 0)) {
508 
509         /* Read from physical memory into packet buffer */
510         bytes = desc.status2 & DESC_STATUS2_BUF_SIZE_MASK;
511         if (bytes + packet_bytes > sizeof(packet_buf)) {
512             desc.status |= TX_DESC_STATUS_LENGTH_ERR;
513             break;
514         }
515         dma_memory_read(&s->dma_as, desc.addr, packet_buf + packet_bytes, bytes);
516         packet_bytes += bytes;
517         desc.status &= ~DESC_STATUS_CTL;
518         allwinner_sun8i_emac_flush_desc(s, &desc, s->tx_desc_curr);
519 
520         /* After the last descriptor, send the packet */
521         if (desc.status2 & TX_DESC_STATUS2_LAST_DESC) {
522             if (desc.status2 & TX_DESC_STATUS2_CHECKSUM_MASK) {
523                 net_checksum_calculate(packet_buf, packet_bytes, CSUM_ALL);
524             }
525 
526             qemu_send_packet(nc, packet_buf, packet_bytes);
527             trace_allwinner_sun8i_emac_transmit(s->tx_desc_curr, desc.addr,
528                                                 bytes);
529 
530             packet_bytes = 0;
531             transmitted++;
532         }
533         s->tx_desc_curr = allwinner_sun8i_emac_next_desc(s, &desc);
534     }
535 
536     /* Raise transmit completed interrupt */
537     if (transmitted > 0) {
538         s->int_sta |= INT_STA_TX;
539         s->tx_ctl1 &= ~TX_CTL1_TX_DMA_START;
540         allwinner_sun8i_emac_update_irq(s);
541     }
542 }
543 
544 static void allwinner_sun8i_emac_reset(DeviceState *dev)
545 {
546     AwSun8iEmacState *s = AW_SUN8I_EMAC(dev);
547     NetClientState *nc = qemu_get_queue(s->nic);
548 
549     trace_allwinner_sun8i_emac_reset();
550 
551     s->mii_cmd = 0;
552     s->mii_data = 0;
553     s->basic_ctl0 = 0;
554     s->basic_ctl1 = REG_BASIC_CTL_1_RST;
555     s->int_en = 0;
556     s->int_sta = 0;
557     s->frm_flt = 0;
558     s->rx_ctl0 = 0;
559     s->rx_ctl1 = RX_CTL1_RX_MD;
560     s->rx_desc_head = 0;
561     s->rx_desc_curr = 0;
562     s->tx_ctl0 = 0;
563     s->tx_ctl1 = 0;
564     s->tx_desc_head = 0;
565     s->tx_desc_curr = 0;
566     s->tx_flowctl = 0;
567 
568     allwinner_sun8i_emac_mii_reset(s, !nc->link_down);
569 }
570 
571 static uint64_t allwinner_sun8i_emac_read(void *opaque, hwaddr offset,
572                                           unsigned size)
573 {
574     AwSun8iEmacState *s = AW_SUN8I_EMAC(opaque);
575     uint64_t value = 0;
576     FrameDescriptor desc;
577 
578     switch (offset) {
579     case REG_BASIC_CTL_0:       /* Basic Control 0 */
580         value = s->basic_ctl0;
581         break;
582     case REG_BASIC_CTL_1:       /* Basic Control 1 */
583         value = s->basic_ctl1;
584         break;
585     case REG_INT_STA:           /* Interrupt Status */
586         value = s->int_sta;
587         break;
588     case REG_INT_EN:            /* Interrupt Enable */
589         value = s->int_en;
590         break;
591     case REG_TX_CTL_0:          /* Transmit Control 0 */
592         value = s->tx_ctl0;
593         break;
594     case REG_TX_CTL_1:          /* Transmit Control 1 */
595         value = s->tx_ctl1;
596         break;
597     case REG_TX_FLOW_CTL:       /* Transmit Flow Control */
598         value = s->tx_flowctl;
599         break;
600     case REG_TX_DMA_DESC_LIST:  /* Transmit Descriptor List Address */
601         value = s->tx_desc_head;
602         break;
603     case REG_RX_CTL_0:          /* Receive Control 0 */
604         value = s->rx_ctl0;
605         break;
606     case REG_RX_CTL_1:          /* Receive Control 1 */
607         value = s->rx_ctl1;
608         break;
609     case REG_RX_DMA_DESC_LIST:  /* Receive Descriptor List Address */
610         value = s->rx_desc_head;
611         break;
612     case REG_FRM_FLT:           /* Receive Frame Filter */
613         value = s->frm_flt;
614         break;
615     case REG_RX_HASH_0:         /* Receive Hash Table 0 */
616     case REG_RX_HASH_1:         /* Receive Hash Table 1 */
617         break;
618     case REG_MII_CMD:           /* Management Interface Command */
619         value = s->mii_cmd;
620         break;
621     case REG_MII_DATA:          /* Management Interface Data */
622         value = s->mii_data;
623         break;
624     case REG_ADDR_HIGH:         /* MAC Address High */
625         value = lduw_le_p(s->conf.macaddr.a + 4);
626         break;
627     case REG_ADDR_LOW:          /* MAC Address Low */
628         value = ldl_le_p(s->conf.macaddr.a);
629         break;
630     case REG_TX_DMA_STA:        /* Transmit DMA Status */
631         break;
632     case REG_TX_CUR_DESC:       /* Transmit Current Descriptor */
633         value = s->tx_desc_curr;
634         break;
635     case REG_TX_CUR_BUF:        /* Transmit Current Buffer */
636         if (s->tx_desc_curr != 0) {
637             dma_memory_read(&s->dma_as, s->tx_desc_curr, &desc, sizeof(desc));
638             value = desc.addr;
639         } else {
640             value = 0;
641         }
642         break;
643     case REG_RX_DMA_STA:        /* Receive DMA Status */
644         break;
645     case REG_RX_CUR_DESC:       /* Receive Current Descriptor */
646         value = s->rx_desc_curr;
647         break;
648     case REG_RX_CUR_BUF:        /* Receive Current Buffer */
649         if (s->rx_desc_curr != 0) {
650             dma_memory_read(&s->dma_as, s->rx_desc_curr, &desc, sizeof(desc));
651             value = desc.addr;
652         } else {
653             value = 0;
654         }
655         break;
656     case REG_RGMII_STA:         /* RGMII Status */
657         break;
658     default:
659         qemu_log_mask(LOG_UNIMP, "allwinner-h3-emac: read access to unknown "
660                                  "EMAC register 0x" TARGET_FMT_plx "\n",
661                                   offset);
662     }
663 
664     trace_allwinner_sun8i_emac_read(offset, value);
665     return value;
666 }
667 
668 static void allwinner_sun8i_emac_write(void *opaque, hwaddr offset,
669                                        uint64_t value, unsigned size)
670 {
671     AwSun8iEmacState *s = AW_SUN8I_EMAC(opaque);
672     NetClientState *nc = qemu_get_queue(s->nic);
673 
674     trace_allwinner_sun8i_emac_write(offset, value);
675 
676     switch (offset) {
677     case REG_BASIC_CTL_0:       /* Basic Control 0 */
678         s->basic_ctl0 = value;
679         break;
680     case REG_BASIC_CTL_1:       /* Basic Control 1 */
681         if (value & BASIC_CTL1_SOFTRST) {
682             allwinner_sun8i_emac_reset(DEVICE(s));
683             value &= ~BASIC_CTL1_SOFTRST;
684         }
685         s->basic_ctl1 = value;
686         if (allwinner_sun8i_emac_can_receive(nc)) {
687             qemu_flush_queued_packets(nc);
688         }
689         break;
690     case REG_INT_STA:           /* Interrupt Status */
691         s->int_sta &= ~value;
692         allwinner_sun8i_emac_update_irq(s);
693         break;
694     case REG_INT_EN:            /* Interrupt Enable */
695         s->int_en = value;
696         allwinner_sun8i_emac_update_irq(s);
697         break;
698     case REG_TX_CTL_0:          /* Transmit Control 0 */
699         s->tx_ctl0 = value;
700         break;
701     case REG_TX_CTL_1:          /* Transmit Control 1 */
702         s->tx_ctl1 = value;
703         if (value & TX_CTL1_TX_DMA_EN) {
704             allwinner_sun8i_emac_transmit(s);
705         }
706         break;
707     case REG_TX_FLOW_CTL:       /* Transmit Flow Control */
708         s->tx_flowctl = value;
709         break;
710     case REG_TX_DMA_DESC_LIST:  /* Transmit Descriptor List Address */
711         s->tx_desc_head = value;
712         s->tx_desc_curr = value;
713         break;
714     case REG_RX_CTL_0:          /* Receive Control 0 */
715         s->rx_ctl0 = value;
716         break;
717     case REG_RX_CTL_1:          /* Receive Control 1 */
718         s->rx_ctl1 = value | RX_CTL1_RX_MD;
719         if ((value & RX_CTL1_RX_DMA_EN) &&
720              allwinner_sun8i_emac_can_receive(nc)) {
721             qemu_flush_queued_packets(nc);
722         }
723         break;
724     case REG_RX_DMA_DESC_LIST:  /* Receive Descriptor List Address */
725         s->rx_desc_head = value;
726         s->rx_desc_curr = value;
727         break;
728     case REG_FRM_FLT:           /* Receive Frame Filter */
729         s->frm_flt = value;
730         break;
731     case REG_RX_HASH_0:         /* Receive Hash Table 0 */
732     case REG_RX_HASH_1:         /* Receive Hash Table 1 */
733         break;
734     case REG_MII_CMD:           /* Management Interface Command */
735         s->mii_cmd = value & ~MII_CMD_PHY_BUSY;
736         allwinner_sun8i_emac_mii_cmd(s);
737         break;
738     case REG_MII_DATA:          /* Management Interface Data */
739         s->mii_data = value;
740         break;
741     case REG_ADDR_HIGH:         /* MAC Address High */
742         stw_le_p(s->conf.macaddr.a + 4, value);
743         break;
744     case REG_ADDR_LOW:          /* MAC Address Low */
745         stl_le_p(s->conf.macaddr.a, value);
746         break;
747     case REG_TX_DMA_STA:        /* Transmit DMA Status */
748     case REG_TX_CUR_DESC:       /* Transmit Current Descriptor */
749     case REG_TX_CUR_BUF:        /* Transmit Current Buffer */
750     case REG_RX_DMA_STA:        /* Receive DMA Status */
751     case REG_RX_CUR_DESC:       /* Receive Current Descriptor */
752     case REG_RX_CUR_BUF:        /* Receive Current Buffer */
753     case REG_RGMII_STA:         /* RGMII Status */
754         break;
755     default:
756         qemu_log_mask(LOG_UNIMP, "allwinner-h3-emac: write access to unknown "
757                                  "EMAC register 0x" TARGET_FMT_plx "\n",
758                                   offset);
759     }
760 }
761 
762 static void allwinner_sun8i_emac_set_link(NetClientState *nc)
763 {
764     AwSun8iEmacState *s = qemu_get_nic_opaque(nc);
765 
766     trace_allwinner_sun8i_emac_set_link(!nc->link_down);
767     allwinner_sun8i_emac_mii_set_link(s, !nc->link_down);
768 }
769 
770 static const MemoryRegionOps allwinner_sun8i_emac_mem_ops = {
771     .read = allwinner_sun8i_emac_read,
772     .write = allwinner_sun8i_emac_write,
773     .endianness = DEVICE_NATIVE_ENDIAN,
774     .valid = {
775         .min_access_size = 4,
776         .max_access_size = 4,
777     },
778     .impl.min_access_size = 4,
779 };
780 
781 static NetClientInfo net_allwinner_sun8i_emac_info = {
782     .type = NET_CLIENT_DRIVER_NIC,
783     .size = sizeof(NICState),
784     .can_receive = allwinner_sun8i_emac_can_receive,
785     .receive = allwinner_sun8i_emac_receive,
786     .link_status_changed = allwinner_sun8i_emac_set_link,
787 };
788 
789 static void allwinner_sun8i_emac_init(Object *obj)
790 {
791     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
792     AwSun8iEmacState *s = AW_SUN8I_EMAC(obj);
793 
794     memory_region_init_io(&s->iomem, OBJECT(s), &allwinner_sun8i_emac_mem_ops,
795                            s, TYPE_AW_SUN8I_EMAC, 64 * KiB);
796     sysbus_init_mmio(sbd, &s->iomem);
797     sysbus_init_irq(sbd, &s->irq);
798 }
799 
800 static void allwinner_sun8i_emac_realize(DeviceState *dev, Error **errp)
801 {
802     AwSun8iEmacState *s = AW_SUN8I_EMAC(dev);
803 
804     if (!s->dma_mr) {
805         error_setg(errp, TYPE_AW_SUN8I_EMAC " 'dma-memory' link not set");
806         return;
807     }
808 
809     address_space_init(&s->dma_as, s->dma_mr, "emac-dma");
810 
811     qemu_macaddr_default_if_unset(&s->conf.macaddr);
812     s->nic = qemu_new_nic(&net_allwinner_sun8i_emac_info, &s->conf,
813                            object_get_typename(OBJECT(dev)), dev->id, s);
814     qemu_format_nic_info_str(qemu_get_queue(s->nic), s->conf.macaddr.a);
815 }
816 
817 static Property allwinner_sun8i_emac_properties[] = {
818     DEFINE_NIC_PROPERTIES(AwSun8iEmacState, conf),
819     DEFINE_PROP_UINT8("phy-addr", AwSun8iEmacState, mii_phy_addr, 0),
820     DEFINE_PROP_LINK("dma-memory", AwSun8iEmacState, dma_mr,
821                      TYPE_MEMORY_REGION, MemoryRegion *),
822     DEFINE_PROP_END_OF_LIST(),
823 };
824 
825 static int allwinner_sun8i_emac_post_load(void *opaque, int version_id)
826 {
827     AwSun8iEmacState *s = opaque;
828 
829     allwinner_sun8i_emac_set_link(qemu_get_queue(s->nic));
830 
831     return 0;
832 }
833 
834 static const VMStateDescription vmstate_aw_emac = {
835     .name = "allwinner-sun8i-emac",
836     .version_id = 1,
837     .minimum_version_id = 1,
838     .post_load = allwinner_sun8i_emac_post_load,
839     .fields = (VMStateField[]) {
840         VMSTATE_UINT8(mii_phy_addr, AwSun8iEmacState),
841         VMSTATE_UINT32(mii_cmd, AwSun8iEmacState),
842         VMSTATE_UINT32(mii_data, AwSun8iEmacState),
843         VMSTATE_UINT32(mii_cr, AwSun8iEmacState),
844         VMSTATE_UINT32(mii_st, AwSun8iEmacState),
845         VMSTATE_UINT32(mii_adv, AwSun8iEmacState),
846         VMSTATE_UINT32(basic_ctl0, AwSun8iEmacState),
847         VMSTATE_UINT32(basic_ctl1, AwSun8iEmacState),
848         VMSTATE_UINT32(int_en, AwSun8iEmacState),
849         VMSTATE_UINT32(int_sta, AwSun8iEmacState),
850         VMSTATE_UINT32(frm_flt, AwSun8iEmacState),
851         VMSTATE_UINT32(rx_ctl0, AwSun8iEmacState),
852         VMSTATE_UINT32(rx_ctl1, AwSun8iEmacState),
853         VMSTATE_UINT32(rx_desc_head, AwSun8iEmacState),
854         VMSTATE_UINT32(rx_desc_curr, AwSun8iEmacState),
855         VMSTATE_UINT32(tx_ctl0, AwSun8iEmacState),
856         VMSTATE_UINT32(tx_ctl1, AwSun8iEmacState),
857         VMSTATE_UINT32(tx_desc_head, AwSun8iEmacState),
858         VMSTATE_UINT32(tx_desc_curr, AwSun8iEmacState),
859         VMSTATE_UINT32(tx_flowctl, AwSun8iEmacState),
860         VMSTATE_END_OF_LIST()
861     }
862 };
863 
864 static void allwinner_sun8i_emac_class_init(ObjectClass *klass, void *data)
865 {
866     DeviceClass *dc = DEVICE_CLASS(klass);
867 
868     dc->realize = allwinner_sun8i_emac_realize;
869     dc->reset = allwinner_sun8i_emac_reset;
870     dc->vmsd = &vmstate_aw_emac;
871     device_class_set_props(dc, allwinner_sun8i_emac_properties);
872 }
873 
874 static const TypeInfo allwinner_sun8i_emac_info = {
875     .name           = TYPE_AW_SUN8I_EMAC,
876     .parent         = TYPE_SYS_BUS_DEVICE,
877     .instance_size  = sizeof(AwSun8iEmacState),
878     .instance_init  = allwinner_sun8i_emac_init,
879     .class_init     = allwinner_sun8i_emac_class_init,
880 };
881 
882 static void allwinner_sun8i_emac_register_types(void)
883 {
884     type_register_static(&allwinner_sun8i_emac_info);
885 }
886 
887 type_init(allwinner_sun8i_emac_register_types)
888