xref: /openbmc/qemu/hw/net/allwinner-sun8i-emac.c (revision 041c2a31)
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 uint32_t allwinner_sun8i_emac_next_desc(AwSun8iEmacState *s,
343                                                FrameDescriptor *desc,
344                                                size_t min_size)
345 {
346     uint32_t paddr = desc->next;
347 
348     dma_memory_read(&s->dma_as, paddr, desc, sizeof(*desc));
349 
350     if ((desc->status & DESC_STATUS_CTL) &&
351         (desc->status2 & DESC_STATUS2_BUF_SIZE_MASK) >= min_size) {
352         return paddr;
353     } else {
354         return 0;
355     }
356 }
357 
358 static uint32_t allwinner_sun8i_emac_get_desc(AwSun8iEmacState *s,
359                                               FrameDescriptor *desc,
360                                               uint32_t start_addr,
361                                               size_t min_size)
362 {
363     uint32_t desc_addr = start_addr;
364 
365     /* Note that the list is a cycle. Last entry points back to the head. */
366     while (desc_addr != 0) {
367         dma_memory_read(&s->dma_as, desc_addr, desc, sizeof(*desc));
368 
369         if ((desc->status & DESC_STATUS_CTL) &&
370             (desc->status2 & DESC_STATUS2_BUF_SIZE_MASK) >= min_size) {
371             return desc_addr;
372         } else if (desc->next == start_addr) {
373             break;
374         } else {
375             desc_addr = desc->next;
376         }
377     }
378 
379     return 0;
380 }
381 
382 static uint32_t allwinner_sun8i_emac_rx_desc(AwSun8iEmacState *s,
383                                              FrameDescriptor *desc,
384                                              size_t min_size)
385 {
386     return allwinner_sun8i_emac_get_desc(s, desc, s->rx_desc_curr, min_size);
387 }
388 
389 static uint32_t allwinner_sun8i_emac_tx_desc(AwSun8iEmacState *s,
390                                              FrameDescriptor *desc,
391                                              size_t min_size)
392 {
393     return allwinner_sun8i_emac_get_desc(s, desc, s->tx_desc_head, min_size);
394 }
395 
396 static void allwinner_sun8i_emac_flush_desc(AwSun8iEmacState *s,
397                                             FrameDescriptor *desc,
398                                             uint32_t phys_addr)
399 {
400     dma_memory_write(&s->dma_as, phys_addr, desc, sizeof(*desc));
401 }
402 
403 static bool allwinner_sun8i_emac_can_receive(NetClientState *nc)
404 {
405     AwSun8iEmacState *s = qemu_get_nic_opaque(nc);
406     FrameDescriptor desc;
407 
408     return (s->rx_ctl0 & RX_CTL0_RX_EN) &&
409            (allwinner_sun8i_emac_rx_desc(s, &desc, 0) != 0);
410 }
411 
412 static ssize_t allwinner_sun8i_emac_receive(NetClientState *nc,
413                                             const uint8_t *buf,
414                                             size_t size)
415 {
416     AwSun8iEmacState *s = qemu_get_nic_opaque(nc);
417     FrameDescriptor desc;
418     size_t bytes_left = size;
419     size_t desc_bytes = 0;
420     size_t pad_fcs_size = 4;
421     size_t padding = 0;
422 
423     if (!(s->rx_ctl0 & RX_CTL0_RX_EN)) {
424         return -1;
425     }
426 
427     s->rx_desc_curr = allwinner_sun8i_emac_rx_desc(s, &desc,
428                                                    AW_SUN8I_EMAC_MIN_PKT_SZ);
429     if (!s->rx_desc_curr) {
430         s->int_sta |= INT_STA_RX_BUF_UA;
431     }
432 
433     /* Keep filling RX descriptors until the whole frame is written */
434     while (s->rx_desc_curr && bytes_left > 0) {
435         desc.status &= ~DESC_STATUS_CTL;
436         desc.status &= ~RX_DESC_STATUS_FRM_LEN_MASK;
437 
438         if (bytes_left == size) {
439             desc.status |= RX_DESC_STATUS_FIRST_DESC;
440         }
441 
442         if ((desc.status2 & DESC_STATUS2_BUF_SIZE_MASK) <
443             (bytes_left + pad_fcs_size)) {
444             desc_bytes = desc.status2 & DESC_STATUS2_BUF_SIZE_MASK;
445             desc.status |= desc_bytes << RX_DESC_STATUS_FRM_LEN_SHIFT;
446         } else {
447             padding = pad_fcs_size;
448             if (bytes_left < AW_SUN8I_EMAC_MIN_PKT_SZ) {
449                 padding += (AW_SUN8I_EMAC_MIN_PKT_SZ - bytes_left);
450             }
451 
452             desc_bytes = (bytes_left);
453             desc.status |= RX_DESC_STATUS_LAST_DESC;
454             desc.status |= (bytes_left + padding)
455                             << RX_DESC_STATUS_FRM_LEN_SHIFT;
456         }
457 
458         dma_memory_write(&s->dma_as, desc.addr, buf, desc_bytes);
459         allwinner_sun8i_emac_flush_desc(s, &desc, s->rx_desc_curr);
460         trace_allwinner_sun8i_emac_receive(s->rx_desc_curr, desc.addr,
461                                            desc_bytes);
462 
463         /* Check if frame needs to raise the receive interrupt */
464         if (!(desc.status2 & RX_DESC_STATUS2_RX_INT_CTL)) {
465             s->int_sta |= INT_STA_RX;
466         }
467 
468         /* Increment variables */
469         buf += desc_bytes;
470         bytes_left -= desc_bytes;
471 
472         /* Move to the next descriptor */
473         s->rx_desc_curr = allwinner_sun8i_emac_next_desc(s, &desc, 64);
474         if (!s->rx_desc_curr) {
475             /* Not enough buffer space available */
476             s->int_sta |= INT_STA_RX_BUF_UA;
477             s->rx_desc_curr = s->rx_desc_head;
478             break;
479         }
480     }
481 
482     /* Report receive DMA is finished */
483     s->rx_ctl1 &= ~RX_CTL1_RX_DMA_START;
484     allwinner_sun8i_emac_update_irq(s);
485 
486     return size;
487 }
488 
489 static void allwinner_sun8i_emac_transmit(AwSun8iEmacState *s)
490 {
491     NetClientState *nc = qemu_get_queue(s->nic);
492     FrameDescriptor desc;
493     size_t bytes = 0;
494     size_t packet_bytes = 0;
495     size_t transmitted = 0;
496     static uint8_t packet_buf[2048];
497 
498     s->tx_desc_curr = allwinner_sun8i_emac_tx_desc(s, &desc, 0);
499 
500     /* Read all transmit descriptors */
501     while (s->tx_desc_curr != 0) {
502 
503         /* Read from physical memory into packet buffer */
504         bytes = desc.status2 & DESC_STATUS2_BUF_SIZE_MASK;
505         if (bytes + packet_bytes > sizeof(packet_buf)) {
506             desc.status |= TX_DESC_STATUS_LENGTH_ERR;
507             break;
508         }
509         dma_memory_read(&s->dma_as, desc.addr, packet_buf + packet_bytes, bytes);
510         packet_bytes += bytes;
511         desc.status &= ~DESC_STATUS_CTL;
512         allwinner_sun8i_emac_flush_desc(s, &desc, s->tx_desc_curr);
513 
514         /* After the last descriptor, send the packet */
515         if (desc.status2 & TX_DESC_STATUS2_LAST_DESC) {
516             if (desc.status2 & TX_DESC_STATUS2_CHECKSUM_MASK) {
517                 net_checksum_calculate(packet_buf, packet_bytes, CSUM_ALL);
518             }
519 
520             qemu_send_packet(nc, packet_buf, packet_bytes);
521             trace_allwinner_sun8i_emac_transmit(s->tx_desc_curr, desc.addr,
522                                                 bytes);
523 
524             packet_bytes = 0;
525             transmitted++;
526         }
527         s->tx_desc_curr = allwinner_sun8i_emac_next_desc(s, &desc, 0);
528     }
529 
530     /* Raise transmit completed interrupt */
531     if (transmitted > 0) {
532         s->int_sta |= INT_STA_TX;
533         s->tx_ctl1 &= ~TX_CTL1_TX_DMA_START;
534         allwinner_sun8i_emac_update_irq(s);
535     }
536 }
537 
538 static void allwinner_sun8i_emac_reset(DeviceState *dev)
539 {
540     AwSun8iEmacState *s = AW_SUN8I_EMAC(dev);
541     NetClientState *nc = qemu_get_queue(s->nic);
542 
543     trace_allwinner_sun8i_emac_reset();
544 
545     s->mii_cmd = 0;
546     s->mii_data = 0;
547     s->basic_ctl0 = 0;
548     s->basic_ctl1 = REG_BASIC_CTL_1_RST;
549     s->int_en = 0;
550     s->int_sta = 0;
551     s->frm_flt = 0;
552     s->rx_ctl0 = 0;
553     s->rx_ctl1 = RX_CTL1_RX_MD;
554     s->rx_desc_head = 0;
555     s->rx_desc_curr = 0;
556     s->tx_ctl0 = 0;
557     s->tx_ctl1 = 0;
558     s->tx_desc_head = 0;
559     s->tx_desc_curr = 0;
560     s->tx_flowctl = 0;
561 
562     allwinner_sun8i_emac_mii_reset(s, !nc->link_down);
563 }
564 
565 static uint64_t allwinner_sun8i_emac_read(void *opaque, hwaddr offset,
566                                           unsigned size)
567 {
568     AwSun8iEmacState *s = AW_SUN8I_EMAC(opaque);
569     uint64_t value = 0;
570     FrameDescriptor desc;
571 
572     switch (offset) {
573     case REG_BASIC_CTL_0:       /* Basic Control 0 */
574         value = s->basic_ctl0;
575         break;
576     case REG_BASIC_CTL_1:       /* Basic Control 1 */
577         value = s->basic_ctl1;
578         break;
579     case REG_INT_STA:           /* Interrupt Status */
580         value = s->int_sta;
581         break;
582     case REG_INT_EN:            /* Interupt Enable */
583         value = s->int_en;
584         break;
585     case REG_TX_CTL_0:          /* Transmit Control 0 */
586         value = s->tx_ctl0;
587         break;
588     case REG_TX_CTL_1:          /* Transmit Control 1 */
589         value = s->tx_ctl1;
590         break;
591     case REG_TX_FLOW_CTL:       /* Transmit Flow Control */
592         value = s->tx_flowctl;
593         break;
594     case REG_TX_DMA_DESC_LIST:  /* Transmit Descriptor List Address */
595         value = s->tx_desc_head;
596         break;
597     case REG_RX_CTL_0:          /* Receive Control 0 */
598         value = s->rx_ctl0;
599         break;
600     case REG_RX_CTL_1:          /* Receive Control 1 */
601         value = s->rx_ctl1;
602         break;
603     case REG_RX_DMA_DESC_LIST:  /* Receive Descriptor List Address */
604         value = s->rx_desc_head;
605         break;
606     case REG_FRM_FLT:           /* Receive Frame Filter */
607         value = s->frm_flt;
608         break;
609     case REG_RX_HASH_0:         /* Receive Hash Table 0 */
610     case REG_RX_HASH_1:         /* Receive Hash Table 1 */
611         break;
612     case REG_MII_CMD:           /* Management Interface Command */
613         value = s->mii_cmd;
614         break;
615     case REG_MII_DATA:          /* Management Interface Data */
616         value = s->mii_data;
617         break;
618     case REG_ADDR_HIGH:         /* MAC Address High */
619         value = lduw_le_p(s->conf.macaddr.a + 4);
620         break;
621     case REG_ADDR_LOW:          /* MAC Address Low */
622         value = ldl_le_p(s->conf.macaddr.a);
623         break;
624     case REG_TX_DMA_STA:        /* Transmit DMA Status */
625         break;
626     case REG_TX_CUR_DESC:       /* Transmit Current Descriptor */
627         value = s->tx_desc_curr;
628         break;
629     case REG_TX_CUR_BUF:        /* Transmit Current Buffer */
630         if (s->tx_desc_curr != 0) {
631             dma_memory_read(&s->dma_as, s->tx_desc_curr, &desc, sizeof(desc));
632             value = desc.addr;
633         } else {
634             value = 0;
635         }
636         break;
637     case REG_RX_DMA_STA:        /* Receive DMA Status */
638         break;
639     case REG_RX_CUR_DESC:       /* Receive Current Descriptor */
640         value = s->rx_desc_curr;
641         break;
642     case REG_RX_CUR_BUF:        /* Receive Current Buffer */
643         if (s->rx_desc_curr != 0) {
644             dma_memory_read(&s->dma_as, s->rx_desc_curr, &desc, sizeof(desc));
645             value = desc.addr;
646         } else {
647             value = 0;
648         }
649         break;
650     case REG_RGMII_STA:         /* RGMII Status */
651         break;
652     default:
653         qemu_log_mask(LOG_UNIMP, "allwinner-h3-emac: read access to unknown "
654                                  "EMAC register 0x" TARGET_FMT_plx "\n",
655                                   offset);
656     }
657 
658     trace_allwinner_sun8i_emac_read(offset, value);
659     return value;
660 }
661 
662 static void allwinner_sun8i_emac_write(void *opaque, hwaddr offset,
663                                        uint64_t value, unsigned size)
664 {
665     AwSun8iEmacState *s = AW_SUN8I_EMAC(opaque);
666     NetClientState *nc = qemu_get_queue(s->nic);
667 
668     trace_allwinner_sun8i_emac_write(offset, value);
669 
670     switch (offset) {
671     case REG_BASIC_CTL_0:       /* Basic Control 0 */
672         s->basic_ctl0 = value;
673         break;
674     case REG_BASIC_CTL_1:       /* Basic Control 1 */
675         if (value & BASIC_CTL1_SOFTRST) {
676             allwinner_sun8i_emac_reset(DEVICE(s));
677             value &= ~BASIC_CTL1_SOFTRST;
678         }
679         s->basic_ctl1 = value;
680         if (allwinner_sun8i_emac_can_receive(nc)) {
681             qemu_flush_queued_packets(nc);
682         }
683         break;
684     case REG_INT_STA:           /* Interrupt Status */
685         s->int_sta &= ~value;
686         allwinner_sun8i_emac_update_irq(s);
687         break;
688     case REG_INT_EN:            /* Interrupt Enable */
689         s->int_en = value;
690         allwinner_sun8i_emac_update_irq(s);
691         break;
692     case REG_TX_CTL_0:          /* Transmit Control 0 */
693         s->tx_ctl0 = value;
694         break;
695     case REG_TX_CTL_1:          /* Transmit Control 1 */
696         s->tx_ctl1 = value;
697         if (value & TX_CTL1_TX_DMA_EN) {
698             allwinner_sun8i_emac_transmit(s);
699         }
700         break;
701     case REG_TX_FLOW_CTL:       /* Transmit Flow Control */
702         s->tx_flowctl = value;
703         break;
704     case REG_TX_DMA_DESC_LIST:  /* Transmit Descriptor List Address */
705         s->tx_desc_head = value;
706         s->tx_desc_curr = value;
707         break;
708     case REG_RX_CTL_0:          /* Receive Control 0 */
709         s->rx_ctl0 = value;
710         break;
711     case REG_RX_CTL_1:          /* Receive Control 1 */
712         s->rx_ctl1 = value | RX_CTL1_RX_MD;
713         if ((value & RX_CTL1_RX_DMA_EN) &&
714              allwinner_sun8i_emac_can_receive(nc)) {
715             qemu_flush_queued_packets(nc);
716         }
717         break;
718     case REG_RX_DMA_DESC_LIST:  /* Receive Descriptor List Address */
719         s->rx_desc_head = value;
720         s->rx_desc_curr = value;
721         break;
722     case REG_FRM_FLT:           /* Receive Frame Filter */
723         s->frm_flt = value;
724         break;
725     case REG_RX_HASH_0:         /* Receive Hash Table 0 */
726     case REG_RX_HASH_1:         /* Receive Hash Table 1 */
727         break;
728     case REG_MII_CMD:           /* Management Interface Command */
729         s->mii_cmd = value & ~MII_CMD_PHY_BUSY;
730         allwinner_sun8i_emac_mii_cmd(s);
731         break;
732     case REG_MII_DATA:          /* Management Interface Data */
733         s->mii_data = value;
734         break;
735     case REG_ADDR_HIGH:         /* MAC Address High */
736         stw_le_p(s->conf.macaddr.a + 4, value);
737         break;
738     case REG_ADDR_LOW:          /* MAC Address Low */
739         stl_le_p(s->conf.macaddr.a, value);
740         break;
741     case REG_TX_DMA_STA:        /* Transmit DMA Status */
742     case REG_TX_CUR_DESC:       /* Transmit Current Descriptor */
743     case REG_TX_CUR_BUF:        /* Transmit Current Buffer */
744     case REG_RX_DMA_STA:        /* Receive DMA Status */
745     case REG_RX_CUR_DESC:       /* Receive Current Descriptor */
746     case REG_RX_CUR_BUF:        /* Receive Current Buffer */
747     case REG_RGMII_STA:         /* RGMII Status */
748         break;
749     default:
750         qemu_log_mask(LOG_UNIMP, "allwinner-h3-emac: write access to unknown "
751                                  "EMAC register 0x" TARGET_FMT_plx "\n",
752                                   offset);
753     }
754 }
755 
756 static void allwinner_sun8i_emac_set_link(NetClientState *nc)
757 {
758     AwSun8iEmacState *s = qemu_get_nic_opaque(nc);
759 
760     trace_allwinner_sun8i_emac_set_link(!nc->link_down);
761     allwinner_sun8i_emac_mii_set_link(s, !nc->link_down);
762 }
763 
764 static const MemoryRegionOps allwinner_sun8i_emac_mem_ops = {
765     .read = allwinner_sun8i_emac_read,
766     .write = allwinner_sun8i_emac_write,
767     .endianness = DEVICE_NATIVE_ENDIAN,
768     .valid = {
769         .min_access_size = 4,
770         .max_access_size = 4,
771     },
772     .impl.min_access_size = 4,
773 };
774 
775 static NetClientInfo net_allwinner_sun8i_emac_info = {
776     .type = NET_CLIENT_DRIVER_NIC,
777     .size = sizeof(NICState),
778     .can_receive = allwinner_sun8i_emac_can_receive,
779     .receive = allwinner_sun8i_emac_receive,
780     .link_status_changed = allwinner_sun8i_emac_set_link,
781 };
782 
783 static void allwinner_sun8i_emac_init(Object *obj)
784 {
785     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
786     AwSun8iEmacState *s = AW_SUN8I_EMAC(obj);
787 
788     memory_region_init_io(&s->iomem, OBJECT(s), &allwinner_sun8i_emac_mem_ops,
789                            s, TYPE_AW_SUN8I_EMAC, 64 * KiB);
790     sysbus_init_mmio(sbd, &s->iomem);
791     sysbus_init_irq(sbd, &s->irq);
792 }
793 
794 static void allwinner_sun8i_emac_realize(DeviceState *dev, Error **errp)
795 {
796     AwSun8iEmacState *s = AW_SUN8I_EMAC(dev);
797 
798     if (!s->dma_mr) {
799         error_setg(errp, TYPE_AW_SUN8I_EMAC " 'dma-memory' link not set");
800         return;
801     }
802 
803     address_space_init(&s->dma_as, s->dma_mr, "emac-dma");
804 
805     qemu_macaddr_default_if_unset(&s->conf.macaddr);
806     s->nic = qemu_new_nic(&net_allwinner_sun8i_emac_info, &s->conf,
807                            object_get_typename(OBJECT(dev)), dev->id, s);
808     qemu_format_nic_info_str(qemu_get_queue(s->nic), s->conf.macaddr.a);
809 }
810 
811 static Property allwinner_sun8i_emac_properties[] = {
812     DEFINE_NIC_PROPERTIES(AwSun8iEmacState, conf),
813     DEFINE_PROP_UINT8("phy-addr", AwSun8iEmacState, mii_phy_addr, 0),
814     DEFINE_PROP_LINK("dma-memory", AwSun8iEmacState, dma_mr,
815                      TYPE_MEMORY_REGION, MemoryRegion *),
816     DEFINE_PROP_END_OF_LIST(),
817 };
818 
819 static int allwinner_sun8i_emac_post_load(void *opaque, int version_id)
820 {
821     AwSun8iEmacState *s = opaque;
822 
823     allwinner_sun8i_emac_set_link(qemu_get_queue(s->nic));
824 
825     return 0;
826 }
827 
828 static const VMStateDescription vmstate_aw_emac = {
829     .name = "allwinner-sun8i-emac",
830     .version_id = 1,
831     .minimum_version_id = 1,
832     .post_load = allwinner_sun8i_emac_post_load,
833     .fields = (VMStateField[]) {
834         VMSTATE_UINT8(mii_phy_addr, AwSun8iEmacState),
835         VMSTATE_UINT32(mii_cmd, AwSun8iEmacState),
836         VMSTATE_UINT32(mii_data, AwSun8iEmacState),
837         VMSTATE_UINT32(mii_cr, AwSun8iEmacState),
838         VMSTATE_UINT32(mii_st, AwSun8iEmacState),
839         VMSTATE_UINT32(mii_adv, AwSun8iEmacState),
840         VMSTATE_UINT32(basic_ctl0, AwSun8iEmacState),
841         VMSTATE_UINT32(basic_ctl1, AwSun8iEmacState),
842         VMSTATE_UINT32(int_en, AwSun8iEmacState),
843         VMSTATE_UINT32(int_sta, AwSun8iEmacState),
844         VMSTATE_UINT32(frm_flt, AwSun8iEmacState),
845         VMSTATE_UINT32(rx_ctl0, AwSun8iEmacState),
846         VMSTATE_UINT32(rx_ctl1, AwSun8iEmacState),
847         VMSTATE_UINT32(rx_desc_head, AwSun8iEmacState),
848         VMSTATE_UINT32(rx_desc_curr, AwSun8iEmacState),
849         VMSTATE_UINT32(tx_ctl0, AwSun8iEmacState),
850         VMSTATE_UINT32(tx_ctl1, AwSun8iEmacState),
851         VMSTATE_UINT32(tx_desc_head, AwSun8iEmacState),
852         VMSTATE_UINT32(tx_desc_curr, AwSun8iEmacState),
853         VMSTATE_UINT32(tx_flowctl, AwSun8iEmacState),
854         VMSTATE_END_OF_LIST()
855     }
856 };
857 
858 static void allwinner_sun8i_emac_class_init(ObjectClass *klass, void *data)
859 {
860     DeviceClass *dc = DEVICE_CLASS(klass);
861 
862     dc->realize = allwinner_sun8i_emac_realize;
863     dc->reset = allwinner_sun8i_emac_reset;
864     dc->vmsd = &vmstate_aw_emac;
865     device_class_set_props(dc, allwinner_sun8i_emac_properties);
866 }
867 
868 static const TypeInfo allwinner_sun8i_emac_info = {
869     .name           = TYPE_AW_SUN8I_EMAC,
870     .parent         = TYPE_SYS_BUS_DEVICE,
871     .instance_size  = sizeof(AwSun8iEmacState),
872     .instance_init  = allwinner_sun8i_emac_init,
873     .class_init     = allwinner_sun8i_emac_class_init,
874 };
875 
876 static void allwinner_sun8i_emac_register_types(void)
877 {
878     type_register_static(&allwinner_sun8i_emac_info);
879 }
880 
881 type_init(allwinner_sun8i_emac_register_types)
882