xref: /openbmc/qemu/hw/net/cadence_gem.c (revision 09a274d8)
1 /*
2  * QEMU Cadence GEM emulation
3  *
4  * Copyright (c) 2011 Xilinx, Inc.
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 <zlib.h> /* For crc32 */
27 
28 #include "hw/net/cadence_gem.h"
29 #include "qapi/error.h"
30 #include "qemu/log.h"
31 #include "sysemu/dma.h"
32 #include "net/checksum.h"
33 
34 #ifdef CADENCE_GEM_ERR_DEBUG
35 #define DB_PRINT(...) do { \
36     fprintf(stderr,  ": %s: ", __func__); \
37     fprintf(stderr, ## __VA_ARGS__); \
38     } while (0)
39 #else
40     #define DB_PRINT(...)
41 #endif
42 
43 #define GEM_NWCTRL        (0x00000000/4) /* Network Control reg */
44 #define GEM_NWCFG         (0x00000004/4) /* Network Config reg */
45 #define GEM_NWSTATUS      (0x00000008/4) /* Network Status reg */
46 #define GEM_USERIO        (0x0000000C/4) /* User IO reg */
47 #define GEM_DMACFG        (0x00000010/4) /* DMA Control reg */
48 #define GEM_TXSTATUS      (0x00000014/4) /* TX Status reg */
49 #define GEM_RXQBASE       (0x00000018/4) /* RX Q Base address reg */
50 #define GEM_TXQBASE       (0x0000001C/4) /* TX Q Base address reg */
51 #define GEM_RXSTATUS      (0x00000020/4) /* RX Status reg */
52 #define GEM_ISR           (0x00000024/4) /* Interrupt Status reg */
53 #define GEM_IER           (0x00000028/4) /* Interrupt Enable reg */
54 #define GEM_IDR           (0x0000002C/4) /* Interrupt Disable reg */
55 #define GEM_IMR           (0x00000030/4) /* Interrupt Mask reg */
56 #define GEM_PHYMNTNC      (0x00000034/4) /* Phy Maintenance reg */
57 #define GEM_RXPAUSE       (0x00000038/4) /* RX Pause Time reg */
58 #define GEM_TXPAUSE       (0x0000003C/4) /* TX Pause Time reg */
59 #define GEM_TXPARTIALSF   (0x00000040/4) /* TX Partial Store and Forward */
60 #define GEM_RXPARTIALSF   (0x00000044/4) /* RX Partial Store and Forward */
61 #define GEM_HASHLO        (0x00000080/4) /* Hash Low address reg */
62 #define GEM_HASHHI        (0x00000084/4) /* Hash High address reg */
63 #define GEM_SPADDR1LO     (0x00000088/4) /* Specific addr 1 low reg */
64 #define GEM_SPADDR1HI     (0x0000008C/4) /* Specific addr 1 high reg */
65 #define GEM_SPADDR2LO     (0x00000090/4) /* Specific addr 2 low reg */
66 #define GEM_SPADDR2HI     (0x00000094/4) /* Specific addr 2 high reg */
67 #define GEM_SPADDR3LO     (0x00000098/4) /* Specific addr 3 low reg */
68 #define GEM_SPADDR3HI     (0x0000009C/4) /* Specific addr 3 high reg */
69 #define GEM_SPADDR4LO     (0x000000A0/4) /* Specific addr 4 low reg */
70 #define GEM_SPADDR4HI     (0x000000A4/4) /* Specific addr 4 high reg */
71 #define GEM_TIDMATCH1     (0x000000A8/4) /* Type ID1 Match reg */
72 #define GEM_TIDMATCH2     (0x000000AC/4) /* Type ID2 Match reg */
73 #define GEM_TIDMATCH3     (0x000000B0/4) /* Type ID3 Match reg */
74 #define GEM_TIDMATCH4     (0x000000B4/4) /* Type ID4 Match reg */
75 #define GEM_WOLAN         (0x000000B8/4) /* Wake on LAN reg */
76 #define GEM_IPGSTRETCH    (0x000000BC/4) /* IPG Stretch reg */
77 #define GEM_SVLAN         (0x000000C0/4) /* Stacked VLAN reg */
78 #define GEM_MODID         (0x000000FC/4) /* Module ID reg */
79 #define GEM_OCTTXLO       (0x00000100/4) /* Octects transmitted Low reg */
80 #define GEM_OCTTXHI       (0x00000104/4) /* Octects transmitted High reg */
81 #define GEM_TXCNT         (0x00000108/4) /* Error-free Frames transmitted */
82 #define GEM_TXBCNT        (0x0000010C/4) /* Error-free Broadcast Frames */
83 #define GEM_TXMCNT        (0x00000110/4) /* Error-free Multicast Frame */
84 #define GEM_TXPAUSECNT    (0x00000114/4) /* Pause Frames Transmitted */
85 #define GEM_TX64CNT       (0x00000118/4) /* Error-free 64 TX */
86 #define GEM_TX65CNT       (0x0000011C/4) /* Error-free 65-127 TX */
87 #define GEM_TX128CNT      (0x00000120/4) /* Error-free 128-255 TX */
88 #define GEM_TX256CNT      (0x00000124/4) /* Error-free 256-511 */
89 #define GEM_TX512CNT      (0x00000128/4) /* Error-free 512-1023 TX */
90 #define GEM_TX1024CNT     (0x0000012C/4) /* Error-free 1024-1518 TX */
91 #define GEM_TX1519CNT     (0x00000130/4) /* Error-free larger than 1519 TX */
92 #define GEM_TXURUNCNT     (0x00000134/4) /* TX under run error counter */
93 #define GEM_SINGLECOLLCNT (0x00000138/4) /* Single Collision Frames */
94 #define GEM_MULTCOLLCNT   (0x0000013C/4) /* Multiple Collision Frames */
95 #define GEM_EXCESSCOLLCNT (0x00000140/4) /* Excessive Collision Frames */
96 #define GEM_LATECOLLCNT   (0x00000144/4) /* Late Collision Frames */
97 #define GEM_DEFERTXCNT    (0x00000148/4) /* Deferred Transmission Frames */
98 #define GEM_CSENSECNT     (0x0000014C/4) /* Carrier Sense Error Counter */
99 #define GEM_OCTRXLO       (0x00000150/4) /* Octects Received register Low */
100 #define GEM_OCTRXHI       (0x00000154/4) /* Octects Received register High */
101 #define GEM_RXCNT         (0x00000158/4) /* Error-free Frames Received */
102 #define GEM_RXBROADCNT    (0x0000015C/4) /* Error-free Broadcast Frames RX */
103 #define GEM_RXMULTICNT    (0x00000160/4) /* Error-free Multicast Frames RX */
104 #define GEM_RXPAUSECNT    (0x00000164/4) /* Pause Frames Received Counter */
105 #define GEM_RX64CNT       (0x00000168/4) /* Error-free 64 byte Frames RX */
106 #define GEM_RX65CNT       (0x0000016C/4) /* Error-free 65-127B Frames RX */
107 #define GEM_RX128CNT      (0x00000170/4) /* Error-free 128-255B Frames RX */
108 #define GEM_RX256CNT      (0x00000174/4) /* Error-free 256-512B Frames RX */
109 #define GEM_RX512CNT      (0x00000178/4) /* Error-free 512-1023B Frames RX */
110 #define GEM_RX1024CNT     (0x0000017C/4) /* Error-free 1024-1518B Frames RX */
111 #define GEM_RX1519CNT     (0x00000180/4) /* Error-free 1519-max Frames RX */
112 #define GEM_RXUNDERCNT    (0x00000184/4) /* Undersize Frames Received */
113 #define GEM_RXOVERCNT     (0x00000188/4) /* Oversize Frames Received */
114 #define GEM_RXJABCNT      (0x0000018C/4) /* Jabbers Received Counter */
115 #define GEM_RXFCSCNT      (0x00000190/4) /* Frame Check seq. Error Counter */
116 #define GEM_RXLENERRCNT   (0x00000194/4) /* Length Field Error Counter */
117 #define GEM_RXSYMERRCNT   (0x00000198/4) /* Symbol Error Counter */
118 #define GEM_RXALIGNERRCNT (0x0000019C/4) /* Alignment Error Counter */
119 #define GEM_RXRSCERRCNT   (0x000001A0/4) /* Receive Resource Error Counter */
120 #define GEM_RXORUNCNT     (0x000001A4/4) /* Receive Overrun Counter */
121 #define GEM_RXIPCSERRCNT  (0x000001A8/4) /* IP header Checksum Error Counter */
122 #define GEM_RXTCPCCNT     (0x000001AC/4) /* TCP Checksum Error Counter */
123 #define GEM_RXUDPCCNT     (0x000001B0/4) /* UDP Checksum Error Counter */
124 
125 #define GEM_1588S         (0x000001D0/4) /* 1588 Timer Seconds */
126 #define GEM_1588NS        (0x000001D4/4) /* 1588 Timer Nanoseconds */
127 #define GEM_1588ADJ       (0x000001D8/4) /* 1588 Timer Adjust */
128 #define GEM_1588INC       (0x000001DC/4) /* 1588 Timer Increment */
129 #define GEM_PTPETXS       (0x000001E0/4) /* PTP Event Frame Transmitted (s) */
130 #define GEM_PTPETXNS      (0x000001E4/4) /* PTP Event Frame Transmitted (ns) */
131 #define GEM_PTPERXS       (0x000001E8/4) /* PTP Event Frame Received (s) */
132 #define GEM_PTPERXNS      (0x000001EC/4) /* PTP Event Frame Received (ns) */
133 #define GEM_PTPPTXS       (0x000001E0/4) /* PTP Peer Frame Transmitted (s) */
134 #define GEM_PTPPTXNS      (0x000001E4/4) /* PTP Peer Frame Transmitted (ns) */
135 #define GEM_PTPPRXS       (0x000001E8/4) /* PTP Peer Frame Received (s) */
136 #define GEM_PTPPRXNS      (0x000001EC/4) /* PTP Peer Frame Received (ns) */
137 
138 /* Design Configuration Registers */
139 #define GEM_DESCONF       (0x00000280/4)
140 #define GEM_DESCONF2      (0x00000284/4)
141 #define GEM_DESCONF3      (0x00000288/4)
142 #define GEM_DESCONF4      (0x0000028C/4)
143 #define GEM_DESCONF5      (0x00000290/4)
144 #define GEM_DESCONF6      (0x00000294/4)
145 #define GEM_DESCONF6_64B_MASK (1U << 23)
146 #define GEM_DESCONF7      (0x00000298/4)
147 
148 #define GEM_INT_Q1_STATUS               (0x00000400 / 4)
149 #define GEM_INT_Q1_MASK                 (0x00000640 / 4)
150 
151 #define GEM_TRANSMIT_Q1_PTR             (0x00000440 / 4)
152 #define GEM_TRANSMIT_Q7_PTR             (GEM_TRANSMIT_Q1_PTR + 6)
153 
154 #define GEM_RECEIVE_Q1_PTR              (0x00000480 / 4)
155 #define GEM_RECEIVE_Q7_PTR              (GEM_RECEIVE_Q1_PTR + 6)
156 
157 #define GEM_TBQPH                       (0x000004C8 / 4)
158 #define GEM_RBQPH                       (0x000004D4 / 4)
159 
160 #define GEM_INT_Q1_ENABLE               (0x00000600 / 4)
161 #define GEM_INT_Q7_ENABLE               (GEM_INT_Q1_ENABLE + 6)
162 
163 #define GEM_INT_Q1_DISABLE              (0x00000620 / 4)
164 #define GEM_INT_Q7_DISABLE              (GEM_INT_Q1_DISABLE + 6)
165 
166 #define GEM_INT_Q1_MASK                 (0x00000640 / 4)
167 #define GEM_INT_Q7_MASK                 (GEM_INT_Q1_MASK + 6)
168 
169 #define GEM_SCREENING_TYPE1_REGISTER_0  (0x00000500 / 4)
170 
171 #define GEM_ST1R_UDP_PORT_MATCH_ENABLE  (1 << 29)
172 #define GEM_ST1R_DSTC_ENABLE            (1 << 28)
173 #define GEM_ST1R_UDP_PORT_MATCH_SHIFT   (12)
174 #define GEM_ST1R_UDP_PORT_MATCH_WIDTH   (27 - GEM_ST1R_UDP_PORT_MATCH_SHIFT + 1)
175 #define GEM_ST1R_DSTC_MATCH_SHIFT       (4)
176 #define GEM_ST1R_DSTC_MATCH_WIDTH       (11 - GEM_ST1R_DSTC_MATCH_SHIFT + 1)
177 #define GEM_ST1R_QUEUE_SHIFT            (0)
178 #define GEM_ST1R_QUEUE_WIDTH            (3 - GEM_ST1R_QUEUE_SHIFT + 1)
179 
180 #define GEM_SCREENING_TYPE2_REGISTER_0  (0x00000540 / 4)
181 
182 #define GEM_ST2R_COMPARE_A_ENABLE       (1 << 18)
183 #define GEM_ST2R_COMPARE_A_SHIFT        (13)
184 #define GEM_ST2R_COMPARE_WIDTH          (17 - GEM_ST2R_COMPARE_A_SHIFT + 1)
185 #define GEM_ST2R_ETHERTYPE_ENABLE       (1 << 12)
186 #define GEM_ST2R_ETHERTYPE_INDEX_SHIFT  (9)
187 #define GEM_ST2R_ETHERTYPE_INDEX_WIDTH  (11 - GEM_ST2R_ETHERTYPE_INDEX_SHIFT \
188                                             + 1)
189 #define GEM_ST2R_QUEUE_SHIFT            (0)
190 #define GEM_ST2R_QUEUE_WIDTH            (3 - GEM_ST2R_QUEUE_SHIFT + 1)
191 
192 #define GEM_SCREENING_TYPE2_ETHERTYPE_REG_0     (0x000006e0 / 4)
193 #define GEM_TYPE2_COMPARE_0_WORD_0              (0x00000700 / 4)
194 
195 #define GEM_T2CW1_COMPARE_OFFSET_SHIFT  (7)
196 #define GEM_T2CW1_COMPARE_OFFSET_WIDTH  (8 - GEM_T2CW1_COMPARE_OFFSET_SHIFT + 1)
197 #define GEM_T2CW1_OFFSET_VALUE_SHIFT    (0)
198 #define GEM_T2CW1_OFFSET_VALUE_WIDTH    (6 - GEM_T2CW1_OFFSET_VALUE_SHIFT + 1)
199 
200 /*****************************************/
201 #define GEM_NWCTRL_TXSTART     0x00000200 /* Transmit Enable */
202 #define GEM_NWCTRL_TXENA       0x00000008 /* Transmit Enable */
203 #define GEM_NWCTRL_RXENA       0x00000004 /* Receive Enable */
204 #define GEM_NWCTRL_LOCALLOOP   0x00000002 /* Local Loopback */
205 
206 #define GEM_NWCFG_STRIP_FCS    0x00020000 /* Strip FCS field */
207 #define GEM_NWCFG_LERR_DISC    0x00010000 /* Discard RX frames with len err */
208 #define GEM_NWCFG_BUFF_OFST_M  0x0000C000 /* Receive buffer offset mask */
209 #define GEM_NWCFG_BUFF_OFST_S  14         /* Receive buffer offset shift */
210 #define GEM_NWCFG_UCAST_HASH   0x00000080 /* accept unicast if hash match */
211 #define GEM_NWCFG_MCAST_HASH   0x00000040 /* accept multicast if hash match */
212 #define GEM_NWCFG_BCAST_REJ    0x00000020 /* Reject broadcast packets */
213 #define GEM_NWCFG_PROMISC      0x00000010 /* Accept all packets */
214 
215 #define GEM_DMACFG_ADDR_64B    (1U << 30)
216 #define GEM_DMACFG_TX_BD_EXT   (1U << 29)
217 #define GEM_DMACFG_RX_BD_EXT   (1U << 28)
218 #define GEM_DMACFG_RBUFSZ_M    0x00FF0000 /* DMA RX Buffer Size mask */
219 #define GEM_DMACFG_RBUFSZ_S    16         /* DMA RX Buffer Size shift */
220 #define GEM_DMACFG_RBUFSZ_MUL  64         /* DMA RX Buffer Size multiplier */
221 #define GEM_DMACFG_TXCSUM_OFFL 0x00000800 /* Transmit checksum offload */
222 
223 #define GEM_TXSTATUS_TXCMPL    0x00000020 /* Transmit Complete */
224 #define GEM_TXSTATUS_USED      0x00000001 /* sw owned descriptor encountered */
225 
226 #define GEM_RXSTATUS_FRMRCVD   0x00000002 /* Frame received */
227 #define GEM_RXSTATUS_NOBUF     0x00000001 /* Buffer unavailable */
228 
229 /* GEM_ISR GEM_IER GEM_IDR GEM_IMR */
230 #define GEM_INT_TXCMPL        0x00000080 /* Transmit Complete */
231 #define GEM_INT_TXUSED         0x00000008
232 #define GEM_INT_RXUSED         0x00000004
233 #define GEM_INT_RXCMPL        0x00000002
234 
235 #define GEM_PHYMNTNC_OP_R      0x20000000 /* read operation */
236 #define GEM_PHYMNTNC_OP_W      0x10000000 /* write operation */
237 #define GEM_PHYMNTNC_ADDR      0x0F800000 /* Address bits */
238 #define GEM_PHYMNTNC_ADDR_SHFT 23
239 #define GEM_PHYMNTNC_REG       0x007C0000 /* register bits */
240 #define GEM_PHYMNTNC_REG_SHIFT 18
241 
242 /* Marvell PHY definitions */
243 #define BOARD_PHY_ADDRESS    23 /* PHY address we will emulate a device at */
244 
245 #define PHY_REG_CONTROL      0
246 #define PHY_REG_STATUS       1
247 #define PHY_REG_PHYID1       2
248 #define PHY_REG_PHYID2       3
249 #define PHY_REG_ANEGADV      4
250 #define PHY_REG_LINKPABIL    5
251 #define PHY_REG_ANEGEXP      6
252 #define PHY_REG_NEXTP        7
253 #define PHY_REG_LINKPNEXTP   8
254 #define PHY_REG_100BTCTRL    9
255 #define PHY_REG_1000BTSTAT   10
256 #define PHY_REG_EXTSTAT      15
257 #define PHY_REG_PHYSPCFC_CTL 16
258 #define PHY_REG_PHYSPCFC_ST  17
259 #define PHY_REG_INT_EN       18
260 #define PHY_REG_INT_ST       19
261 #define PHY_REG_EXT_PHYSPCFC_CTL  20
262 #define PHY_REG_RXERR        21
263 #define PHY_REG_EACD         22
264 #define PHY_REG_LED          24
265 #define PHY_REG_LED_OVRD     25
266 #define PHY_REG_EXT_PHYSPCFC_CTL2 26
267 #define PHY_REG_EXT_PHYSPCFC_ST   27
268 #define PHY_REG_CABLE_DIAG   28
269 
270 #define PHY_REG_CONTROL_RST  0x8000
271 #define PHY_REG_CONTROL_LOOP 0x4000
272 #define PHY_REG_CONTROL_ANEG 0x1000
273 
274 #define PHY_REG_STATUS_LINK     0x0004
275 #define PHY_REG_STATUS_ANEGCMPL 0x0020
276 
277 #define PHY_REG_INT_ST_ANEGCMPL 0x0800
278 #define PHY_REG_INT_ST_LINKC    0x0400
279 #define PHY_REG_INT_ST_ENERGY   0x0010
280 
281 /***********************************************************************/
282 #define GEM_RX_REJECT                   (-1)
283 #define GEM_RX_PROMISCUOUS_ACCEPT       (-2)
284 #define GEM_RX_BROADCAST_ACCEPT         (-3)
285 #define GEM_RX_MULTICAST_HASH_ACCEPT    (-4)
286 #define GEM_RX_UNICAST_HASH_ACCEPT      (-5)
287 
288 #define GEM_RX_SAR_ACCEPT               0
289 
290 /***********************************************************************/
291 
292 #define DESC_1_USED 0x80000000
293 #define DESC_1_LENGTH 0x00001FFF
294 
295 #define DESC_1_TX_WRAP 0x40000000
296 #define DESC_1_TX_LAST 0x00008000
297 
298 #define DESC_0_RX_WRAP 0x00000002
299 #define DESC_0_RX_OWNERSHIP 0x00000001
300 
301 #define R_DESC_1_RX_SAR_SHIFT           25
302 #define R_DESC_1_RX_SAR_LENGTH          2
303 #define R_DESC_1_RX_SAR_MATCH           (1 << 27)
304 #define R_DESC_1_RX_UNICAST_HASH        (1 << 29)
305 #define R_DESC_1_RX_MULTICAST_HASH      (1 << 30)
306 #define R_DESC_1_RX_BROADCAST           (1 << 31)
307 
308 #define DESC_1_RX_SOF 0x00004000
309 #define DESC_1_RX_EOF 0x00008000
310 
311 #define GEM_MODID_VALUE 0x00020118
312 
313 static inline uint64_t tx_desc_get_buffer(CadenceGEMState *s, uint32_t *desc)
314 {
315     uint64_t ret = desc[0];
316 
317     if (s->regs[GEM_DMACFG] & GEM_DMACFG_ADDR_64B) {
318         ret |= (uint64_t)desc[2] << 32;
319     }
320     return ret;
321 }
322 
323 static inline unsigned tx_desc_get_used(uint32_t *desc)
324 {
325     return (desc[1] & DESC_1_USED) ? 1 : 0;
326 }
327 
328 static inline void tx_desc_set_used(uint32_t *desc)
329 {
330     desc[1] |= DESC_1_USED;
331 }
332 
333 static inline unsigned tx_desc_get_wrap(uint32_t *desc)
334 {
335     return (desc[1] & DESC_1_TX_WRAP) ? 1 : 0;
336 }
337 
338 static inline unsigned tx_desc_get_last(uint32_t *desc)
339 {
340     return (desc[1] & DESC_1_TX_LAST) ? 1 : 0;
341 }
342 
343 static inline void tx_desc_set_last(uint32_t *desc)
344 {
345     desc[1] |= DESC_1_TX_LAST;
346 }
347 
348 static inline unsigned tx_desc_get_length(uint32_t *desc)
349 {
350     return desc[1] & DESC_1_LENGTH;
351 }
352 
353 static inline void print_gem_tx_desc(uint32_t *desc, uint8_t queue)
354 {
355     DB_PRINT("TXDESC (queue %" PRId8 "):\n", queue);
356     DB_PRINT("bufaddr: 0x%08x\n", *desc);
357     DB_PRINT("used_hw: %d\n", tx_desc_get_used(desc));
358     DB_PRINT("wrap:    %d\n", tx_desc_get_wrap(desc));
359     DB_PRINT("last:    %d\n", tx_desc_get_last(desc));
360     DB_PRINT("length:  %d\n", tx_desc_get_length(desc));
361 }
362 
363 static inline uint64_t rx_desc_get_buffer(CadenceGEMState *s, uint32_t *desc)
364 {
365     uint64_t ret = desc[0] & ~0x3UL;
366 
367     if (s->regs[GEM_DMACFG] & GEM_DMACFG_ADDR_64B) {
368         ret |= (uint64_t)desc[2] << 32;
369     }
370     return ret;
371 }
372 
373 static inline int gem_get_desc_len(CadenceGEMState *s, bool rx_n_tx)
374 {
375     int ret = 2;
376 
377     if (s->regs[GEM_DMACFG] & GEM_DMACFG_ADDR_64B) {
378         ret += 2;
379     }
380     if (s->regs[GEM_DMACFG] & (rx_n_tx ? GEM_DMACFG_RX_BD_EXT
381                                        : GEM_DMACFG_TX_BD_EXT)) {
382         ret += 2;
383     }
384 
385     assert(ret <= DESC_MAX_NUM_WORDS);
386     return ret;
387 }
388 
389 static inline unsigned rx_desc_get_wrap(uint32_t *desc)
390 {
391     return desc[0] & DESC_0_RX_WRAP ? 1 : 0;
392 }
393 
394 static inline unsigned rx_desc_get_ownership(uint32_t *desc)
395 {
396     return desc[0] & DESC_0_RX_OWNERSHIP ? 1 : 0;
397 }
398 
399 static inline void rx_desc_set_ownership(uint32_t *desc)
400 {
401     desc[0] |= DESC_0_RX_OWNERSHIP;
402 }
403 
404 static inline void rx_desc_set_sof(uint32_t *desc)
405 {
406     desc[1] |= DESC_1_RX_SOF;
407 }
408 
409 static inline void rx_desc_set_eof(uint32_t *desc)
410 {
411     desc[1] |= DESC_1_RX_EOF;
412 }
413 
414 static inline void rx_desc_set_length(uint32_t *desc, unsigned len)
415 {
416     desc[1] &= ~DESC_1_LENGTH;
417     desc[1] |= len;
418 }
419 
420 static inline void rx_desc_set_broadcast(uint32_t *desc)
421 {
422     desc[1] |= R_DESC_1_RX_BROADCAST;
423 }
424 
425 static inline void rx_desc_set_unicast_hash(uint32_t *desc)
426 {
427     desc[1] |= R_DESC_1_RX_UNICAST_HASH;
428 }
429 
430 static inline void rx_desc_set_multicast_hash(uint32_t *desc)
431 {
432     desc[1] |= R_DESC_1_RX_MULTICAST_HASH;
433 }
434 
435 static inline void rx_desc_set_sar(uint32_t *desc, int sar_idx)
436 {
437     desc[1] = deposit32(desc[1], R_DESC_1_RX_SAR_SHIFT, R_DESC_1_RX_SAR_LENGTH,
438                         sar_idx);
439     desc[1] |= R_DESC_1_RX_SAR_MATCH;
440 }
441 
442 /* The broadcast MAC address: 0xFFFFFFFFFFFF */
443 static const uint8_t broadcast_addr[] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
444 
445 /*
446  * gem_init_register_masks:
447  * One time initialization.
448  * Set masks to identify which register bits have magical clear properties
449  */
450 static void gem_init_register_masks(CadenceGEMState *s)
451 {
452     /* Mask of register bits which are read only */
453     memset(&s->regs_ro[0], 0, sizeof(s->regs_ro));
454     s->regs_ro[GEM_NWCTRL]   = 0xFFF80000;
455     s->regs_ro[GEM_NWSTATUS] = 0xFFFFFFFF;
456     s->regs_ro[GEM_DMACFG]   = 0x8E00F000;
457     s->regs_ro[GEM_TXSTATUS] = 0xFFFFFE08;
458     s->regs_ro[GEM_RXQBASE]  = 0x00000003;
459     s->regs_ro[GEM_TXQBASE]  = 0x00000003;
460     s->regs_ro[GEM_RXSTATUS] = 0xFFFFFFF0;
461     s->regs_ro[GEM_ISR]      = 0xFFFFFFFF;
462     s->regs_ro[GEM_IMR]      = 0xFFFFFFFF;
463     s->regs_ro[GEM_MODID]    = 0xFFFFFFFF;
464 
465     /* Mask of register bits which are clear on read */
466     memset(&s->regs_rtc[0], 0, sizeof(s->regs_rtc));
467     s->regs_rtc[GEM_ISR]      = 0xFFFFFFFF;
468 
469     /* Mask of register bits which are write 1 to clear */
470     memset(&s->regs_w1c[0], 0, sizeof(s->regs_w1c));
471     s->regs_w1c[GEM_TXSTATUS] = 0x000001F7;
472     s->regs_w1c[GEM_RXSTATUS] = 0x0000000F;
473 
474     /* Mask of register bits which are write only */
475     memset(&s->regs_wo[0], 0, sizeof(s->regs_wo));
476     s->regs_wo[GEM_NWCTRL]   = 0x00073E60;
477     s->regs_wo[GEM_IER]      = 0x07FFFFFF;
478     s->regs_wo[GEM_IDR]      = 0x07FFFFFF;
479 }
480 
481 /*
482  * phy_update_link:
483  * Make the emulated PHY link state match the QEMU "interface" state.
484  */
485 static void phy_update_link(CadenceGEMState *s)
486 {
487     DB_PRINT("down %d\n", qemu_get_queue(s->nic)->link_down);
488 
489     /* Autonegotiation status mirrors link status.  */
490     if (qemu_get_queue(s->nic)->link_down) {
491         s->phy_regs[PHY_REG_STATUS] &= ~(PHY_REG_STATUS_ANEGCMPL |
492                                          PHY_REG_STATUS_LINK);
493         s->phy_regs[PHY_REG_INT_ST] |= PHY_REG_INT_ST_LINKC;
494     } else {
495         s->phy_regs[PHY_REG_STATUS] |= (PHY_REG_STATUS_ANEGCMPL |
496                                          PHY_REG_STATUS_LINK);
497         s->phy_regs[PHY_REG_INT_ST] |= (PHY_REG_INT_ST_LINKC |
498                                         PHY_REG_INT_ST_ANEGCMPL |
499                                         PHY_REG_INT_ST_ENERGY);
500     }
501 }
502 
503 static int gem_can_receive(NetClientState *nc)
504 {
505     CadenceGEMState *s;
506     int i;
507 
508     s = qemu_get_nic_opaque(nc);
509 
510     /* Do nothing if receive is not enabled. */
511     if (!(s->regs[GEM_NWCTRL] & GEM_NWCTRL_RXENA)) {
512         if (s->can_rx_state != 1) {
513             s->can_rx_state = 1;
514             DB_PRINT("can't receive - no enable\n");
515         }
516         return 0;
517     }
518 
519     for (i = 0; i < s->num_priority_queues; i++) {
520         if (rx_desc_get_ownership(s->rx_desc[i]) != 1) {
521             break;
522         }
523     };
524 
525     if (i == s->num_priority_queues) {
526         if (s->can_rx_state != 2) {
527             s->can_rx_state = 2;
528             DB_PRINT("can't receive - all the buffer descriptors are busy\n");
529         }
530         return 0;
531     }
532 
533     if (s->can_rx_state != 0) {
534         s->can_rx_state = 0;
535         DB_PRINT("can receive\n");
536     }
537     return 1;
538 }
539 
540 /*
541  * gem_update_int_status:
542  * Raise or lower interrupt based on current status.
543  */
544 static void gem_update_int_status(CadenceGEMState *s)
545 {
546     int i;
547 
548     if (!s->regs[GEM_ISR]) {
549         /* ISR isn't set, clear all the interrupts */
550         for (i = 0; i < s->num_priority_queues; ++i) {
551             qemu_set_irq(s->irq[i], 0);
552         }
553         return;
554     }
555 
556     /* If we get here we know s->regs[GEM_ISR] is set, so we don't need to
557      * check it again.
558      */
559     if (s->num_priority_queues == 1) {
560         /* No priority queues, just trigger the interrupt */
561         DB_PRINT("asserting int.\n");
562         qemu_set_irq(s->irq[0], 1);
563         return;
564     }
565 
566     for (i = 0; i < s->num_priority_queues; ++i) {
567         if (s->regs[GEM_INT_Q1_STATUS + i]) {
568             DB_PRINT("asserting int. (q=%d)\n", i);
569             qemu_set_irq(s->irq[i], 1);
570         }
571     }
572 }
573 
574 /*
575  * gem_receive_updatestats:
576  * Increment receive statistics.
577  */
578 static void gem_receive_updatestats(CadenceGEMState *s, const uint8_t *packet,
579                                     unsigned bytes)
580 {
581     uint64_t octets;
582 
583     /* Total octets (bytes) received */
584     octets = ((uint64_t)(s->regs[GEM_OCTRXLO]) << 32) |
585              s->regs[GEM_OCTRXHI];
586     octets += bytes;
587     s->regs[GEM_OCTRXLO] = octets >> 32;
588     s->regs[GEM_OCTRXHI] = octets;
589 
590     /* Error-free Frames received */
591     s->regs[GEM_RXCNT]++;
592 
593     /* Error-free Broadcast Frames counter */
594     if (!memcmp(packet, broadcast_addr, 6)) {
595         s->regs[GEM_RXBROADCNT]++;
596     }
597 
598     /* Error-free Multicast Frames counter */
599     if (packet[0] == 0x01) {
600         s->regs[GEM_RXMULTICNT]++;
601     }
602 
603     if (bytes <= 64) {
604         s->regs[GEM_RX64CNT]++;
605     } else if (bytes <= 127) {
606         s->regs[GEM_RX65CNT]++;
607     } else if (bytes <= 255) {
608         s->regs[GEM_RX128CNT]++;
609     } else if (bytes <= 511) {
610         s->regs[GEM_RX256CNT]++;
611     } else if (bytes <= 1023) {
612         s->regs[GEM_RX512CNT]++;
613     } else if (bytes <= 1518) {
614         s->regs[GEM_RX1024CNT]++;
615     } else {
616         s->regs[GEM_RX1519CNT]++;
617     }
618 }
619 
620 /*
621  * Get the MAC Address bit from the specified position
622  */
623 static unsigned get_bit(const uint8_t *mac, unsigned bit)
624 {
625     unsigned byte;
626 
627     byte = mac[bit / 8];
628     byte >>= (bit & 0x7);
629     byte &= 1;
630 
631     return byte;
632 }
633 
634 /*
635  * Calculate a GEM MAC Address hash index
636  */
637 static unsigned calc_mac_hash(const uint8_t *mac)
638 {
639     int index_bit, mac_bit;
640     unsigned hash_index;
641 
642     hash_index = 0;
643     mac_bit = 5;
644     for (index_bit = 5; index_bit >= 0; index_bit--) {
645         hash_index |= (get_bit(mac,  mac_bit) ^
646                                get_bit(mac, mac_bit + 6) ^
647                                get_bit(mac, mac_bit + 12) ^
648                                get_bit(mac, mac_bit + 18) ^
649                                get_bit(mac, mac_bit + 24) ^
650                                get_bit(mac, mac_bit + 30) ^
651                                get_bit(mac, mac_bit + 36) ^
652                                get_bit(mac, mac_bit + 42)) << index_bit;
653         mac_bit--;
654     }
655 
656     return hash_index;
657 }
658 
659 /*
660  * gem_mac_address_filter:
661  * Accept or reject this destination address?
662  * Returns:
663  * GEM_RX_REJECT: reject
664  * >= 0: Specific address accept (which matched SAR is returned)
665  * others for various other modes of accept:
666  * GEM_RM_PROMISCUOUS_ACCEPT, GEM_RX_BROADCAST_ACCEPT,
667  * GEM_RX_MULTICAST_HASH_ACCEPT or GEM_RX_UNICAST_HASH_ACCEPT
668  */
669 static int gem_mac_address_filter(CadenceGEMState *s, const uint8_t *packet)
670 {
671     uint8_t *gem_spaddr;
672     int i;
673 
674     /* Promiscuous mode? */
675     if (s->regs[GEM_NWCFG] & GEM_NWCFG_PROMISC) {
676         return GEM_RX_PROMISCUOUS_ACCEPT;
677     }
678 
679     if (!memcmp(packet, broadcast_addr, 6)) {
680         /* Reject broadcast packets? */
681         if (s->regs[GEM_NWCFG] & GEM_NWCFG_BCAST_REJ) {
682             return GEM_RX_REJECT;
683         }
684         return GEM_RX_BROADCAST_ACCEPT;
685     }
686 
687     /* Accept packets -w- hash match? */
688     if ((packet[0] == 0x01 && (s->regs[GEM_NWCFG] & GEM_NWCFG_MCAST_HASH)) ||
689         (packet[0] != 0x01 && (s->regs[GEM_NWCFG] & GEM_NWCFG_UCAST_HASH))) {
690         unsigned hash_index;
691 
692         hash_index = calc_mac_hash(packet);
693         if (hash_index < 32) {
694             if (s->regs[GEM_HASHLO] & (1<<hash_index)) {
695                 return packet[0] == 0x01 ? GEM_RX_MULTICAST_HASH_ACCEPT :
696                                            GEM_RX_UNICAST_HASH_ACCEPT;
697             }
698         } else {
699             hash_index -= 32;
700             if (s->regs[GEM_HASHHI] & (1<<hash_index)) {
701                 return packet[0] == 0x01 ? GEM_RX_MULTICAST_HASH_ACCEPT :
702                                            GEM_RX_UNICAST_HASH_ACCEPT;
703             }
704         }
705     }
706 
707     /* Check all 4 specific addresses */
708     gem_spaddr = (uint8_t *)&(s->regs[GEM_SPADDR1LO]);
709     for (i = 3; i >= 0; i--) {
710         if (s->sar_active[i] && !memcmp(packet, gem_spaddr + 8 * i, 6)) {
711             return GEM_RX_SAR_ACCEPT + i;
712         }
713     }
714 
715     /* No address match; reject the packet */
716     return GEM_RX_REJECT;
717 }
718 
719 /* Figure out which queue the received data should be sent to */
720 static int get_queue_from_screen(CadenceGEMState *s, uint8_t *rxbuf_ptr,
721                                  unsigned rxbufsize)
722 {
723     uint32_t reg;
724     bool matched, mismatched;
725     int i, j;
726 
727     for (i = 0; i < s->num_type1_screeners; i++) {
728         reg = s->regs[GEM_SCREENING_TYPE1_REGISTER_0 + i];
729         matched = false;
730         mismatched = false;
731 
732         /* Screening is based on UDP Port */
733         if (reg & GEM_ST1R_UDP_PORT_MATCH_ENABLE) {
734             uint16_t udp_port = rxbuf_ptr[14 + 22] << 8 | rxbuf_ptr[14 + 23];
735             if (udp_port == extract32(reg, GEM_ST1R_UDP_PORT_MATCH_SHIFT,
736                                            GEM_ST1R_UDP_PORT_MATCH_WIDTH)) {
737                 matched = true;
738             } else {
739                 mismatched = true;
740             }
741         }
742 
743         /* Screening is based on DS/TC */
744         if (reg & GEM_ST1R_DSTC_ENABLE) {
745             uint8_t dscp = rxbuf_ptr[14 + 1];
746             if (dscp == extract32(reg, GEM_ST1R_DSTC_MATCH_SHIFT,
747                                        GEM_ST1R_DSTC_MATCH_WIDTH)) {
748                 matched = true;
749             } else {
750                 mismatched = true;
751             }
752         }
753 
754         if (matched && !mismatched) {
755             return extract32(reg, GEM_ST1R_QUEUE_SHIFT, GEM_ST1R_QUEUE_WIDTH);
756         }
757     }
758 
759     for (i = 0; i < s->num_type2_screeners; i++) {
760         reg = s->regs[GEM_SCREENING_TYPE2_REGISTER_0 + i];
761         matched = false;
762         mismatched = false;
763 
764         if (reg & GEM_ST2R_ETHERTYPE_ENABLE) {
765             uint16_t type = rxbuf_ptr[12] << 8 | rxbuf_ptr[13];
766             int et_idx = extract32(reg, GEM_ST2R_ETHERTYPE_INDEX_SHIFT,
767                                         GEM_ST2R_ETHERTYPE_INDEX_WIDTH);
768 
769             if (et_idx > s->num_type2_screeners) {
770                 qemu_log_mask(LOG_GUEST_ERROR, "Out of range ethertype "
771                               "register index: %d\n", et_idx);
772             }
773             if (type == s->regs[GEM_SCREENING_TYPE2_ETHERTYPE_REG_0 +
774                                 et_idx]) {
775                 matched = true;
776             } else {
777                 mismatched = true;
778             }
779         }
780 
781         /* Compare A, B, C */
782         for (j = 0; j < 3; j++) {
783             uint32_t cr0, cr1, mask;
784             uint16_t rx_cmp;
785             int offset;
786             int cr_idx = extract32(reg, GEM_ST2R_COMPARE_A_SHIFT + j * 6,
787                                         GEM_ST2R_COMPARE_WIDTH);
788 
789             if (!(reg & (GEM_ST2R_COMPARE_A_ENABLE << (j * 6)))) {
790                 continue;
791             }
792             if (cr_idx > s->num_type2_screeners) {
793                 qemu_log_mask(LOG_GUEST_ERROR, "Out of range compare "
794                               "register index: %d\n", cr_idx);
795             }
796 
797             cr0 = s->regs[GEM_TYPE2_COMPARE_0_WORD_0 + cr_idx * 2];
798             cr1 = s->regs[GEM_TYPE2_COMPARE_0_WORD_0 + cr_idx * 2 + 1];
799             offset = extract32(cr1, GEM_T2CW1_OFFSET_VALUE_SHIFT,
800                                     GEM_T2CW1_OFFSET_VALUE_WIDTH);
801 
802             switch (extract32(cr1, GEM_T2CW1_COMPARE_OFFSET_SHIFT,
803                                    GEM_T2CW1_COMPARE_OFFSET_WIDTH)) {
804             case 3: /* Skip UDP header */
805                 qemu_log_mask(LOG_UNIMP, "TCP compare offsets"
806                               "unimplemented - assuming UDP\n");
807                 offset += 8;
808                 /* Fallthrough */
809             case 2: /* skip the IP header */
810                 offset += 20;
811                 /* Fallthrough */
812             case 1: /* Count from after the ethertype */
813                 offset += 14;
814                 break;
815             case 0:
816                 /* Offset from start of frame */
817                 break;
818             }
819 
820             rx_cmp = rxbuf_ptr[offset] << 8 | rxbuf_ptr[offset];
821             mask = extract32(cr0, 0, 16);
822 
823             if ((rx_cmp & mask) == (extract32(cr0, 16, 16) & mask)) {
824                 matched = true;
825             } else {
826                 mismatched = true;
827             }
828         }
829 
830         if (matched && !mismatched) {
831             return extract32(reg, GEM_ST2R_QUEUE_SHIFT, GEM_ST2R_QUEUE_WIDTH);
832         }
833     }
834 
835     /* We made it here, assume it's queue 0 */
836     return 0;
837 }
838 
839 static hwaddr gem_get_desc_addr(CadenceGEMState *s, bool tx, int q)
840 {
841     hwaddr desc_addr = 0;
842 
843     if (s->regs[GEM_DMACFG] & GEM_DMACFG_ADDR_64B) {
844         desc_addr = s->regs[tx ? GEM_TBQPH : GEM_RBQPH];
845     }
846     desc_addr <<= 32;
847     desc_addr |= tx ? s->tx_desc_addr[q] : s->rx_desc_addr[q];
848     return desc_addr;
849 }
850 
851 static hwaddr gem_get_tx_desc_addr(CadenceGEMState *s, int q)
852 {
853     return gem_get_desc_addr(s, true, q);
854 }
855 
856 static hwaddr gem_get_rx_desc_addr(CadenceGEMState *s, int q)
857 {
858     return gem_get_desc_addr(s, false, q);
859 }
860 
861 static void gem_get_rx_desc(CadenceGEMState *s, int q)
862 {
863     hwaddr desc_addr = gem_get_rx_desc_addr(s, q);
864 
865     DB_PRINT("read descriptor 0x%" HWADDR_PRIx "\n", desc_addr);
866 
867     /* read current descriptor */
868     address_space_read(&s->dma_as, desc_addr, MEMTXATTRS_UNSPECIFIED,
869                        (uint8_t *)s->rx_desc[q],
870                        sizeof(uint32_t) * gem_get_desc_len(s, true));
871 
872     /* Descriptor owned by software ? */
873     if (rx_desc_get_ownership(s->rx_desc[q]) == 1) {
874         DB_PRINT("descriptor 0x%" HWADDR_PRIx " owned by sw.\n", desc_addr);
875         s->regs[GEM_RXSTATUS] |= GEM_RXSTATUS_NOBUF;
876         s->regs[GEM_ISR] |= GEM_INT_RXUSED & ~(s->regs[GEM_IMR]);
877         /* Handle interrupt consequences */
878         gem_update_int_status(s);
879     }
880 }
881 
882 /*
883  * gem_receive:
884  * Fit a packet handed to us by QEMU into the receive descriptor ring.
885  */
886 static ssize_t gem_receive(NetClientState *nc, const uint8_t *buf, size_t size)
887 {
888     CadenceGEMState *s;
889     unsigned   rxbufsize, bytes_to_copy;
890     unsigned   rxbuf_offset;
891     uint8_t    rxbuf[2048];
892     uint8_t   *rxbuf_ptr;
893     bool first_desc = true;
894     int maf;
895     int q = 0;
896 
897     s = qemu_get_nic_opaque(nc);
898 
899     /* Is this destination MAC address "for us" ? */
900     maf = gem_mac_address_filter(s, buf);
901     if (maf == GEM_RX_REJECT) {
902         return -1;
903     }
904 
905     /* Discard packets with receive length error enabled ? */
906     if (s->regs[GEM_NWCFG] & GEM_NWCFG_LERR_DISC) {
907         unsigned type_len;
908 
909         /* Fish the ethertype / length field out of the RX packet */
910         type_len = buf[12] << 8 | buf[13];
911         /* It is a length field, not an ethertype */
912         if (type_len < 0x600) {
913             if (size < type_len) {
914                 /* discard */
915                 return -1;
916             }
917         }
918     }
919 
920     /*
921      * Determine configured receive buffer offset (probably 0)
922      */
923     rxbuf_offset = (s->regs[GEM_NWCFG] & GEM_NWCFG_BUFF_OFST_M) >>
924                    GEM_NWCFG_BUFF_OFST_S;
925 
926     /* The configure size of each receive buffer.  Determines how many
927      * buffers needed to hold this packet.
928      */
929     rxbufsize = ((s->regs[GEM_DMACFG] & GEM_DMACFG_RBUFSZ_M) >>
930                  GEM_DMACFG_RBUFSZ_S) * GEM_DMACFG_RBUFSZ_MUL;
931     bytes_to_copy = size;
932 
933     /* Hardware allows a zero value here but warns against it. To avoid QEMU
934      * indefinite loops we enforce a minimum value here
935      */
936     if (rxbufsize < GEM_DMACFG_RBUFSZ_MUL) {
937         rxbufsize = GEM_DMACFG_RBUFSZ_MUL;
938     }
939 
940     /* Pad to minimum length. Assume FCS field is stripped, logic
941      * below will increment it to the real minimum of 64 when
942      * not FCS stripping
943      */
944     if (size < 60) {
945         size = 60;
946     }
947 
948     /* Strip of FCS field ? (usually yes) */
949     if (s->regs[GEM_NWCFG] & GEM_NWCFG_STRIP_FCS) {
950         rxbuf_ptr = (void *)buf;
951     } else {
952         unsigned crc_val;
953 
954         if (size > sizeof(rxbuf) - sizeof(crc_val)) {
955             size = sizeof(rxbuf) - sizeof(crc_val);
956         }
957         bytes_to_copy = size;
958         /* The application wants the FCS field, which QEMU does not provide.
959          * We must try and calculate one.
960          */
961 
962         memcpy(rxbuf, buf, size);
963         memset(rxbuf + size, 0, sizeof(rxbuf) - size);
964         rxbuf_ptr = rxbuf;
965         crc_val = cpu_to_le32(crc32(0, rxbuf, MAX(size, 60)));
966         memcpy(rxbuf + size, &crc_val, sizeof(crc_val));
967 
968         bytes_to_copy += 4;
969         size += 4;
970     }
971 
972     DB_PRINT("config bufsize: %d packet size: %ld\n", rxbufsize, size);
973 
974     /* Find which queue we are targeting */
975     q = get_queue_from_screen(s, rxbuf_ptr, rxbufsize);
976 
977     while (bytes_to_copy) {
978         hwaddr desc_addr;
979 
980         /* Do nothing if receive is not enabled. */
981         if (!gem_can_receive(nc)) {
982             return -1;
983         }
984 
985         DB_PRINT("copy %d bytes to 0x%x\n", MIN(bytes_to_copy, rxbufsize),
986                 rx_desc_get_buffer(s->rx_desc[q]));
987 
988         /* Copy packet data to emulated DMA buffer */
989         address_space_write(&s->dma_as, rx_desc_get_buffer(s, s->rx_desc[q]) +
990                                                                   rxbuf_offset,
991                             MEMTXATTRS_UNSPECIFIED, rxbuf_ptr,
992                             MIN(bytes_to_copy, rxbufsize));
993         rxbuf_ptr += MIN(bytes_to_copy, rxbufsize);
994         bytes_to_copy -= MIN(bytes_to_copy, rxbufsize);
995 
996         /* Update the descriptor.  */
997         if (first_desc) {
998             rx_desc_set_sof(s->rx_desc[q]);
999             first_desc = false;
1000         }
1001         if (bytes_to_copy == 0) {
1002             rx_desc_set_eof(s->rx_desc[q]);
1003             rx_desc_set_length(s->rx_desc[q], size);
1004         }
1005         rx_desc_set_ownership(s->rx_desc[q]);
1006 
1007         switch (maf) {
1008         case GEM_RX_PROMISCUOUS_ACCEPT:
1009             break;
1010         case GEM_RX_BROADCAST_ACCEPT:
1011             rx_desc_set_broadcast(s->rx_desc[q]);
1012             break;
1013         case GEM_RX_UNICAST_HASH_ACCEPT:
1014             rx_desc_set_unicast_hash(s->rx_desc[q]);
1015             break;
1016         case GEM_RX_MULTICAST_HASH_ACCEPT:
1017             rx_desc_set_multicast_hash(s->rx_desc[q]);
1018             break;
1019         case GEM_RX_REJECT:
1020             abort();
1021         default: /* SAR */
1022             rx_desc_set_sar(s->rx_desc[q], maf);
1023         }
1024 
1025         /* Descriptor write-back.  */
1026         desc_addr = gem_get_rx_desc_addr(s, q);
1027         address_space_write(&s->dma_as, desc_addr,
1028                             MEMTXATTRS_UNSPECIFIED,
1029                             (uint8_t *)s->rx_desc[q],
1030                             sizeof(uint32_t) * gem_get_desc_len(s, true));
1031 
1032         /* Next descriptor */
1033         if (rx_desc_get_wrap(s->rx_desc[q])) {
1034             DB_PRINT("wrapping RX descriptor list\n");
1035             s->rx_desc_addr[q] = s->regs[GEM_RXQBASE];
1036         } else {
1037             DB_PRINT("incrementing RX descriptor list\n");
1038             s->rx_desc_addr[q] += 4 * gem_get_desc_len(s, true);
1039         }
1040 
1041         gem_get_rx_desc(s, q);
1042     }
1043 
1044     /* Count it */
1045     gem_receive_updatestats(s, buf, size);
1046 
1047     s->regs[GEM_RXSTATUS] |= GEM_RXSTATUS_FRMRCVD;
1048     s->regs[GEM_ISR] |= GEM_INT_RXCMPL & ~(s->regs[GEM_IMR]);
1049 
1050     /* Handle interrupt consequences */
1051     gem_update_int_status(s);
1052 
1053     return size;
1054 }
1055 
1056 /*
1057  * gem_transmit_updatestats:
1058  * Increment transmit statistics.
1059  */
1060 static void gem_transmit_updatestats(CadenceGEMState *s, const uint8_t *packet,
1061                                      unsigned bytes)
1062 {
1063     uint64_t octets;
1064 
1065     /* Total octets (bytes) transmitted */
1066     octets = ((uint64_t)(s->regs[GEM_OCTTXLO]) << 32) |
1067              s->regs[GEM_OCTTXHI];
1068     octets += bytes;
1069     s->regs[GEM_OCTTXLO] = octets >> 32;
1070     s->regs[GEM_OCTTXHI] = octets;
1071 
1072     /* Error-free Frames transmitted */
1073     s->regs[GEM_TXCNT]++;
1074 
1075     /* Error-free Broadcast Frames counter */
1076     if (!memcmp(packet, broadcast_addr, 6)) {
1077         s->regs[GEM_TXBCNT]++;
1078     }
1079 
1080     /* Error-free Multicast Frames counter */
1081     if (packet[0] == 0x01) {
1082         s->regs[GEM_TXMCNT]++;
1083     }
1084 
1085     if (bytes <= 64) {
1086         s->regs[GEM_TX64CNT]++;
1087     } else if (bytes <= 127) {
1088         s->regs[GEM_TX65CNT]++;
1089     } else if (bytes <= 255) {
1090         s->regs[GEM_TX128CNT]++;
1091     } else if (bytes <= 511) {
1092         s->regs[GEM_TX256CNT]++;
1093     } else if (bytes <= 1023) {
1094         s->regs[GEM_TX512CNT]++;
1095     } else if (bytes <= 1518) {
1096         s->regs[GEM_TX1024CNT]++;
1097     } else {
1098         s->regs[GEM_TX1519CNT]++;
1099     }
1100 }
1101 
1102 /*
1103  * gem_transmit:
1104  * Fish packets out of the descriptor ring and feed them to QEMU
1105  */
1106 static void gem_transmit(CadenceGEMState *s)
1107 {
1108     uint32_t desc[DESC_MAX_NUM_WORDS];
1109     hwaddr packet_desc_addr;
1110     uint8_t     tx_packet[2048];
1111     uint8_t     *p;
1112     unsigned    total_bytes;
1113     int q = 0;
1114 
1115     /* Do nothing if transmit is not enabled. */
1116     if (!(s->regs[GEM_NWCTRL] & GEM_NWCTRL_TXENA)) {
1117         return;
1118     }
1119 
1120     DB_PRINT("\n");
1121 
1122     /* The packet we will hand off to QEMU.
1123      * Packets scattered across multiple descriptors are gathered to this
1124      * one contiguous buffer first.
1125      */
1126     p = tx_packet;
1127     total_bytes = 0;
1128 
1129     for (q = s->num_priority_queues - 1; q >= 0; q--) {
1130         /* read current descriptor */
1131         packet_desc_addr = gem_get_tx_desc_addr(s, q);
1132 
1133         DB_PRINT("read descriptor 0x%" HWADDR_PRIx "\n", packet_desc_addr);
1134         address_space_read(&s->dma_as, packet_desc_addr,
1135                            MEMTXATTRS_UNSPECIFIED, (uint8_t *)desc,
1136                            sizeof(uint32_t) * gem_get_desc_len(s, false));
1137         /* Handle all descriptors owned by hardware */
1138         while (tx_desc_get_used(desc) == 0) {
1139 
1140             /* Do nothing if transmit is not enabled. */
1141             if (!(s->regs[GEM_NWCTRL] & GEM_NWCTRL_TXENA)) {
1142                 return;
1143             }
1144             print_gem_tx_desc(desc, q);
1145 
1146             /* The real hardware would eat this (and possibly crash).
1147              * For QEMU let's lend a helping hand.
1148              */
1149             if ((tx_desc_get_buffer(s, desc) == 0) ||
1150                 (tx_desc_get_length(desc) == 0)) {
1151                 DB_PRINT("Invalid TX descriptor @ 0x%x\n",
1152                          (unsigned)packet_desc_addr);
1153                 break;
1154             }
1155 
1156             if (tx_desc_get_length(desc) > sizeof(tx_packet) -
1157                                                (p - tx_packet)) {
1158                 DB_PRINT("TX descriptor @ 0x%x too large: size 0x%x space " \
1159                          "0x%x\n", (unsigned)packet_desc_addr,
1160                          (unsigned)tx_desc_get_length(desc),
1161                          sizeof(tx_packet) - (p - tx_packet));
1162                 break;
1163             }
1164 
1165             /* Gather this fragment of the packet from "dma memory" to our
1166              * contig buffer.
1167              */
1168             address_space_read(&s->dma_as, tx_desc_get_buffer(s, desc),
1169                                MEMTXATTRS_UNSPECIFIED,
1170                                p, tx_desc_get_length(desc));
1171             p += tx_desc_get_length(desc);
1172             total_bytes += tx_desc_get_length(desc);
1173 
1174             /* Last descriptor for this packet; hand the whole thing off */
1175             if (tx_desc_get_last(desc)) {
1176                 uint32_t desc_first[DESC_MAX_NUM_WORDS];
1177                 hwaddr desc_addr = gem_get_tx_desc_addr(s, q);
1178 
1179                 /* Modify the 1st descriptor of this packet to be owned by
1180                  * the processor.
1181                  */
1182                 address_space_read(&s->dma_as, desc_addr,
1183                                    MEMTXATTRS_UNSPECIFIED,
1184                                    (uint8_t *)desc_first,
1185                                    sizeof(desc_first));
1186                 tx_desc_set_used(desc_first);
1187                 address_space_write(&s->dma_as, desc_addr,
1188                                   MEMTXATTRS_UNSPECIFIED,
1189                                   (uint8_t *)desc_first,
1190                                    sizeof(desc_first));
1191                 /* Advance the hardware current descriptor past this packet */
1192                 if (tx_desc_get_wrap(desc)) {
1193                     s->tx_desc_addr[q] = s->regs[GEM_TXQBASE];
1194                 } else {
1195                     s->tx_desc_addr[q] = packet_desc_addr +
1196                                          4 * gem_get_desc_len(s, false);
1197                 }
1198                 DB_PRINT("TX descriptor next: 0x%08x\n", s->tx_desc_addr[q]);
1199 
1200                 s->regs[GEM_TXSTATUS] |= GEM_TXSTATUS_TXCMPL;
1201                 s->regs[GEM_ISR] |= GEM_INT_TXCMPL & ~(s->regs[GEM_IMR]);
1202 
1203                 /* Update queue interrupt status */
1204                 if (s->num_priority_queues > 1) {
1205                     s->regs[GEM_INT_Q1_STATUS + q] |=
1206                             GEM_INT_TXCMPL & ~(s->regs[GEM_INT_Q1_MASK + q]);
1207                 }
1208 
1209                 /* Handle interrupt consequences */
1210                 gem_update_int_status(s);
1211 
1212                 /* Is checksum offload enabled? */
1213                 if (s->regs[GEM_DMACFG] & GEM_DMACFG_TXCSUM_OFFL) {
1214                     net_checksum_calculate(tx_packet, total_bytes);
1215                 }
1216 
1217                 /* Update MAC statistics */
1218                 gem_transmit_updatestats(s, tx_packet, total_bytes);
1219 
1220                 /* Send the packet somewhere */
1221                 if (s->phy_loop || (s->regs[GEM_NWCTRL] &
1222                                     GEM_NWCTRL_LOCALLOOP)) {
1223                     gem_receive(qemu_get_queue(s->nic), tx_packet,
1224                                 total_bytes);
1225                 } else {
1226                     qemu_send_packet(qemu_get_queue(s->nic), tx_packet,
1227                                      total_bytes);
1228                 }
1229 
1230                 /* Prepare for next packet */
1231                 p = tx_packet;
1232                 total_bytes = 0;
1233             }
1234 
1235             /* read next descriptor */
1236             if (tx_desc_get_wrap(desc)) {
1237                 tx_desc_set_last(desc);
1238                 packet_desc_addr = s->regs[GEM_TXQBASE];
1239             } else {
1240                 packet_desc_addr += 4 * gem_get_desc_len(s, false);
1241             }
1242             DB_PRINT("read descriptor 0x%" HWADDR_PRIx "\n", packet_desc_addr);
1243             address_space_read(&s->dma_as, packet_desc_addr,
1244                               MEMTXATTRS_UNSPECIFIED, (uint8_t *)desc,
1245                               sizeof(uint32_t) * gem_get_desc_len(s, false));
1246         }
1247 
1248         if (tx_desc_get_used(desc)) {
1249             s->regs[GEM_TXSTATUS] |= GEM_TXSTATUS_USED;
1250             s->regs[GEM_ISR] |= GEM_INT_TXUSED & ~(s->regs[GEM_IMR]);
1251             gem_update_int_status(s);
1252         }
1253     }
1254 }
1255 
1256 static void gem_phy_reset(CadenceGEMState *s)
1257 {
1258     memset(&s->phy_regs[0], 0, sizeof(s->phy_regs));
1259     s->phy_regs[PHY_REG_CONTROL] = 0x1140;
1260     s->phy_regs[PHY_REG_STATUS] = 0x7969;
1261     s->phy_regs[PHY_REG_PHYID1] = 0x0141;
1262     s->phy_regs[PHY_REG_PHYID2] = 0x0CC2;
1263     s->phy_regs[PHY_REG_ANEGADV] = 0x01E1;
1264     s->phy_regs[PHY_REG_LINKPABIL] = 0xCDE1;
1265     s->phy_regs[PHY_REG_ANEGEXP] = 0x000F;
1266     s->phy_regs[PHY_REG_NEXTP] = 0x2001;
1267     s->phy_regs[PHY_REG_LINKPNEXTP] = 0x40E6;
1268     s->phy_regs[PHY_REG_100BTCTRL] = 0x0300;
1269     s->phy_regs[PHY_REG_1000BTSTAT] = 0x7C00;
1270     s->phy_regs[PHY_REG_EXTSTAT] = 0x3000;
1271     s->phy_regs[PHY_REG_PHYSPCFC_CTL] = 0x0078;
1272     s->phy_regs[PHY_REG_PHYSPCFC_ST] = 0x7C00;
1273     s->phy_regs[PHY_REG_EXT_PHYSPCFC_CTL] = 0x0C60;
1274     s->phy_regs[PHY_REG_LED] = 0x4100;
1275     s->phy_regs[PHY_REG_EXT_PHYSPCFC_CTL2] = 0x000A;
1276     s->phy_regs[PHY_REG_EXT_PHYSPCFC_ST] = 0x848B;
1277 
1278     phy_update_link(s);
1279 }
1280 
1281 static void gem_reset(DeviceState *d)
1282 {
1283     int i;
1284     CadenceGEMState *s = CADENCE_GEM(d);
1285     const uint8_t *a;
1286     uint32_t queues_mask = 0;
1287 
1288     DB_PRINT("\n");
1289 
1290     /* Set post reset register values */
1291     memset(&s->regs[0], 0, sizeof(s->regs));
1292     s->regs[GEM_NWCFG] = 0x00080000;
1293     s->regs[GEM_NWSTATUS] = 0x00000006;
1294     s->regs[GEM_DMACFG] = 0x00020784;
1295     s->regs[GEM_IMR] = 0x07ffffff;
1296     s->regs[GEM_TXPAUSE] = 0x0000ffff;
1297     s->regs[GEM_TXPARTIALSF] = 0x000003ff;
1298     s->regs[GEM_RXPARTIALSF] = 0x000003ff;
1299     s->regs[GEM_MODID] = s->revision;
1300     s->regs[GEM_DESCONF] = 0x02500111;
1301     s->regs[GEM_DESCONF2] = 0x2ab13fff;
1302     s->regs[GEM_DESCONF5] = 0x002f2045;
1303     s->regs[GEM_DESCONF6] = GEM_DESCONF6_64B_MASK;
1304 
1305     if (s->num_priority_queues > 1) {
1306         queues_mask = MAKE_64BIT_MASK(1, s->num_priority_queues - 1);
1307         s->regs[GEM_DESCONF6] |= queues_mask;
1308     }
1309 
1310     /* Set MAC address */
1311     a = &s->conf.macaddr.a[0];
1312     s->regs[GEM_SPADDR1LO] = a[0] | (a[1] << 8) | (a[2] << 16) | (a[3] << 24);
1313     s->regs[GEM_SPADDR1HI] = a[4] | (a[5] << 8);
1314 
1315     for (i = 0; i < 4; i++) {
1316         s->sar_active[i] = false;
1317     }
1318 
1319     gem_phy_reset(s);
1320 
1321     gem_update_int_status(s);
1322 }
1323 
1324 static uint16_t gem_phy_read(CadenceGEMState *s, unsigned reg_num)
1325 {
1326     DB_PRINT("reg: %d value: 0x%04x\n", reg_num, s->phy_regs[reg_num]);
1327     return s->phy_regs[reg_num];
1328 }
1329 
1330 static void gem_phy_write(CadenceGEMState *s, unsigned reg_num, uint16_t val)
1331 {
1332     DB_PRINT("reg: %d value: 0x%04x\n", reg_num, val);
1333 
1334     switch (reg_num) {
1335     case PHY_REG_CONTROL:
1336         if (val & PHY_REG_CONTROL_RST) {
1337             /* Phy reset */
1338             gem_phy_reset(s);
1339             val &= ~(PHY_REG_CONTROL_RST | PHY_REG_CONTROL_LOOP);
1340             s->phy_loop = 0;
1341         }
1342         if (val & PHY_REG_CONTROL_ANEG) {
1343             /* Complete autonegotiation immediately */
1344             val &= ~PHY_REG_CONTROL_ANEG;
1345             s->phy_regs[PHY_REG_STATUS] |= PHY_REG_STATUS_ANEGCMPL;
1346         }
1347         if (val & PHY_REG_CONTROL_LOOP) {
1348             DB_PRINT("PHY placed in loopback\n");
1349             s->phy_loop = 1;
1350         } else {
1351             s->phy_loop = 0;
1352         }
1353         break;
1354     }
1355     s->phy_regs[reg_num] = val;
1356 }
1357 
1358 /*
1359  * gem_read32:
1360  * Read a GEM register.
1361  */
1362 static uint64_t gem_read(void *opaque, hwaddr offset, unsigned size)
1363 {
1364     CadenceGEMState *s;
1365     uint32_t retval;
1366     s = (CadenceGEMState *)opaque;
1367 
1368     offset >>= 2;
1369     retval = s->regs[offset];
1370 
1371     DB_PRINT("offset: 0x%04x read: 0x%08x\n", (unsigned)offset*4, retval);
1372 
1373     switch (offset) {
1374     case GEM_ISR:
1375         DB_PRINT("lowering irqs on ISR read\n");
1376         /* The interrupts get updated at the end of the function. */
1377         break;
1378     case GEM_PHYMNTNC:
1379         if (retval & GEM_PHYMNTNC_OP_R) {
1380             uint32_t phy_addr, reg_num;
1381 
1382             phy_addr = (retval & GEM_PHYMNTNC_ADDR) >> GEM_PHYMNTNC_ADDR_SHFT;
1383             if (phy_addr == BOARD_PHY_ADDRESS || phy_addr == 0) {
1384                 reg_num = (retval & GEM_PHYMNTNC_REG) >> GEM_PHYMNTNC_REG_SHIFT;
1385                 retval &= 0xFFFF0000;
1386                 retval |= gem_phy_read(s, reg_num);
1387             } else {
1388                 retval |= 0xFFFF; /* No device at this address */
1389             }
1390         }
1391         break;
1392     }
1393 
1394     /* Squash read to clear bits */
1395     s->regs[offset] &= ~(s->regs_rtc[offset]);
1396 
1397     /* Do not provide write only bits */
1398     retval &= ~(s->regs_wo[offset]);
1399 
1400     DB_PRINT("0x%08x\n", retval);
1401     gem_update_int_status(s);
1402     return retval;
1403 }
1404 
1405 /*
1406  * gem_write32:
1407  * Write a GEM register.
1408  */
1409 static void gem_write(void *opaque, hwaddr offset, uint64_t val,
1410         unsigned size)
1411 {
1412     CadenceGEMState *s = (CadenceGEMState *)opaque;
1413     uint32_t readonly;
1414     int i;
1415 
1416     DB_PRINT("offset: 0x%04x write: 0x%08x ", (unsigned)offset, (unsigned)val);
1417     offset >>= 2;
1418 
1419     /* Squash bits which are read only in write value */
1420     val &= ~(s->regs_ro[offset]);
1421     /* Preserve (only) bits which are read only and wtc in register */
1422     readonly = s->regs[offset] & (s->regs_ro[offset] | s->regs_w1c[offset]);
1423 
1424     /* Copy register write to backing store */
1425     s->regs[offset] = (val & ~s->regs_w1c[offset]) | readonly;
1426 
1427     /* do w1c */
1428     s->regs[offset] &= ~(s->regs_w1c[offset] & val);
1429 
1430     /* Handle register write side effects */
1431     switch (offset) {
1432     case GEM_NWCTRL:
1433         if (val & GEM_NWCTRL_RXENA) {
1434             for (i = 0; i < s->num_priority_queues; ++i) {
1435                 gem_get_rx_desc(s, i);
1436             }
1437         }
1438         if (val & GEM_NWCTRL_TXSTART) {
1439             gem_transmit(s);
1440         }
1441         if (!(val & GEM_NWCTRL_TXENA)) {
1442             /* Reset to start of Q when transmit disabled. */
1443             for (i = 0; i < s->num_priority_queues; i++) {
1444                 s->tx_desc_addr[i] = s->regs[GEM_TXQBASE];
1445             }
1446         }
1447         if (gem_can_receive(qemu_get_queue(s->nic))) {
1448             qemu_flush_queued_packets(qemu_get_queue(s->nic));
1449         }
1450         break;
1451 
1452     case GEM_TXSTATUS:
1453         gem_update_int_status(s);
1454         break;
1455     case GEM_RXQBASE:
1456         s->rx_desc_addr[0] = val;
1457         break;
1458     case GEM_RECEIVE_Q1_PTR ... GEM_RECEIVE_Q7_PTR:
1459         s->rx_desc_addr[offset - GEM_RECEIVE_Q1_PTR + 1] = val;
1460         break;
1461     case GEM_TXQBASE:
1462         s->tx_desc_addr[0] = val;
1463         break;
1464     case GEM_TRANSMIT_Q1_PTR ... GEM_TRANSMIT_Q7_PTR:
1465         s->tx_desc_addr[offset - GEM_TRANSMIT_Q1_PTR + 1] = val;
1466         break;
1467     case GEM_RXSTATUS:
1468         gem_update_int_status(s);
1469         break;
1470     case GEM_IER:
1471         s->regs[GEM_IMR] &= ~val;
1472         gem_update_int_status(s);
1473         break;
1474     case GEM_INT_Q1_ENABLE ... GEM_INT_Q7_ENABLE:
1475         s->regs[GEM_INT_Q1_MASK + offset - GEM_INT_Q1_ENABLE] &= ~val;
1476         gem_update_int_status(s);
1477         break;
1478     case GEM_IDR:
1479         s->regs[GEM_IMR] |= val;
1480         gem_update_int_status(s);
1481         break;
1482     case GEM_INT_Q1_DISABLE ... GEM_INT_Q7_DISABLE:
1483         s->regs[GEM_INT_Q1_MASK + offset - GEM_INT_Q1_DISABLE] |= val;
1484         gem_update_int_status(s);
1485         break;
1486     case GEM_SPADDR1LO:
1487     case GEM_SPADDR2LO:
1488     case GEM_SPADDR3LO:
1489     case GEM_SPADDR4LO:
1490         s->sar_active[(offset - GEM_SPADDR1LO) / 2] = false;
1491         break;
1492     case GEM_SPADDR1HI:
1493     case GEM_SPADDR2HI:
1494     case GEM_SPADDR3HI:
1495     case GEM_SPADDR4HI:
1496         s->sar_active[(offset - GEM_SPADDR1HI) / 2] = true;
1497         break;
1498     case GEM_PHYMNTNC:
1499         if (val & GEM_PHYMNTNC_OP_W) {
1500             uint32_t phy_addr, reg_num;
1501 
1502             phy_addr = (val & GEM_PHYMNTNC_ADDR) >> GEM_PHYMNTNC_ADDR_SHFT;
1503             if (phy_addr == BOARD_PHY_ADDRESS || phy_addr == 0) {
1504                 reg_num = (val & GEM_PHYMNTNC_REG) >> GEM_PHYMNTNC_REG_SHIFT;
1505                 gem_phy_write(s, reg_num, val);
1506             }
1507         }
1508         break;
1509     }
1510 
1511     DB_PRINT("newval: 0x%08x\n", s->regs[offset]);
1512 }
1513 
1514 static const MemoryRegionOps gem_ops = {
1515     .read = gem_read,
1516     .write = gem_write,
1517     .endianness = DEVICE_LITTLE_ENDIAN,
1518 };
1519 
1520 static void gem_set_link(NetClientState *nc)
1521 {
1522     CadenceGEMState *s = qemu_get_nic_opaque(nc);
1523 
1524     DB_PRINT("\n");
1525     phy_update_link(s);
1526     gem_update_int_status(s);
1527 }
1528 
1529 static NetClientInfo net_gem_info = {
1530     .type = NET_CLIENT_DRIVER_NIC,
1531     .size = sizeof(NICState),
1532     .can_receive = gem_can_receive,
1533     .receive = gem_receive,
1534     .link_status_changed = gem_set_link,
1535 };
1536 
1537 static void gem_realize(DeviceState *dev, Error **errp)
1538 {
1539     CadenceGEMState *s = CADENCE_GEM(dev);
1540     int i;
1541 
1542     address_space_init(&s->dma_as,
1543                        s->dma_mr ? s->dma_mr : get_system_memory(), "dma");
1544 
1545     if (s->num_priority_queues == 0 ||
1546         s->num_priority_queues > MAX_PRIORITY_QUEUES) {
1547         error_setg(errp, "Invalid num-priority-queues value: %" PRIx8,
1548                    s->num_priority_queues);
1549         return;
1550     } else if (s->num_type1_screeners > MAX_TYPE1_SCREENERS) {
1551         error_setg(errp, "Invalid num-type1-screeners value: %" PRIx8,
1552                    s->num_type1_screeners);
1553         return;
1554     } else if (s->num_type2_screeners > MAX_TYPE2_SCREENERS) {
1555         error_setg(errp, "Invalid num-type2-screeners value: %" PRIx8,
1556                    s->num_type2_screeners);
1557         return;
1558     }
1559 
1560     for (i = 0; i < s->num_priority_queues; ++i) {
1561         sysbus_init_irq(SYS_BUS_DEVICE(dev), &s->irq[i]);
1562     }
1563 
1564     qemu_macaddr_default_if_unset(&s->conf.macaddr);
1565 
1566     s->nic = qemu_new_nic(&net_gem_info, &s->conf,
1567                           object_get_typename(OBJECT(dev)), dev->id, s);
1568 }
1569 
1570 static void gem_init(Object *obj)
1571 {
1572     CadenceGEMState *s = CADENCE_GEM(obj);
1573     DeviceState *dev = DEVICE(obj);
1574 
1575     DB_PRINT("\n");
1576 
1577     gem_init_register_masks(s);
1578     memory_region_init_io(&s->iomem, OBJECT(s), &gem_ops, s,
1579                           "enet", sizeof(s->regs));
1580 
1581     sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->iomem);
1582 
1583     object_property_add_link(obj, "dma", TYPE_MEMORY_REGION,
1584                              (Object **)&s->dma_mr,
1585                              qdev_prop_allow_set_link_before_realize,
1586                              OBJ_PROP_LINK_STRONG,
1587                              &error_abort);
1588 }
1589 
1590 static const VMStateDescription vmstate_cadence_gem = {
1591     .name = "cadence_gem",
1592     .version_id = 4,
1593     .minimum_version_id = 4,
1594     .fields = (VMStateField[]) {
1595         VMSTATE_UINT32_ARRAY(regs, CadenceGEMState, CADENCE_GEM_MAXREG),
1596         VMSTATE_UINT16_ARRAY(phy_regs, CadenceGEMState, 32),
1597         VMSTATE_UINT8(phy_loop, CadenceGEMState),
1598         VMSTATE_UINT32_ARRAY(rx_desc_addr, CadenceGEMState,
1599                              MAX_PRIORITY_QUEUES),
1600         VMSTATE_UINT32_ARRAY(tx_desc_addr, CadenceGEMState,
1601                              MAX_PRIORITY_QUEUES),
1602         VMSTATE_BOOL_ARRAY(sar_active, CadenceGEMState, 4),
1603         VMSTATE_END_OF_LIST(),
1604     }
1605 };
1606 
1607 static Property gem_properties[] = {
1608     DEFINE_NIC_PROPERTIES(CadenceGEMState, conf),
1609     DEFINE_PROP_UINT32("revision", CadenceGEMState, revision,
1610                        GEM_MODID_VALUE),
1611     DEFINE_PROP_UINT8("num-priority-queues", CadenceGEMState,
1612                       num_priority_queues, 1),
1613     DEFINE_PROP_UINT8("num-type1-screeners", CadenceGEMState,
1614                       num_type1_screeners, 4),
1615     DEFINE_PROP_UINT8("num-type2-screeners", CadenceGEMState,
1616                       num_type2_screeners, 4),
1617     DEFINE_PROP_END_OF_LIST(),
1618 };
1619 
1620 static void gem_class_init(ObjectClass *klass, void *data)
1621 {
1622     DeviceClass *dc = DEVICE_CLASS(klass);
1623 
1624     dc->realize = gem_realize;
1625     dc->props = gem_properties;
1626     dc->vmsd = &vmstate_cadence_gem;
1627     dc->reset = gem_reset;
1628 }
1629 
1630 static const TypeInfo gem_info = {
1631     .name  = TYPE_CADENCE_GEM,
1632     .parent = TYPE_SYS_BUS_DEVICE,
1633     .instance_size  = sizeof(CadenceGEMState),
1634     .instance_init = gem_init,
1635     .class_init = gem_class_init,
1636 };
1637 
1638 static void gem_register_types(void)
1639 {
1640     type_register_static(&gem_info);
1641 }
1642 
1643 type_init(gem_register_types)
1644