xref: /openbmc/qemu/hw/net/cadence_gem.c (revision 5f333d79)
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 "net/checksum.h"
32 
33 #ifdef CADENCE_GEM_ERR_DEBUG
34 #define DB_PRINT(...) do { \
35     fprintf(stderr,  ": %s: ", __func__); \
36     fprintf(stderr, ## __VA_ARGS__); \
37     } while (0);
38 #else
39     #define DB_PRINT(...)
40 #endif
41 
42 #define GEM_NWCTRL        (0x00000000/4) /* Network Control reg */
43 #define GEM_NWCFG         (0x00000004/4) /* Network Config reg */
44 #define GEM_NWSTATUS      (0x00000008/4) /* Network Status reg */
45 #define GEM_USERIO        (0x0000000C/4) /* User IO reg */
46 #define GEM_DMACFG        (0x00000010/4) /* DMA Control reg */
47 #define GEM_TXSTATUS      (0x00000014/4) /* TX Status reg */
48 #define GEM_RXQBASE       (0x00000018/4) /* RX Q Base address reg */
49 #define GEM_TXQBASE       (0x0000001C/4) /* TX Q Base address reg */
50 #define GEM_RXSTATUS      (0x00000020/4) /* RX Status reg */
51 #define GEM_ISR           (0x00000024/4) /* Interrupt Status reg */
52 #define GEM_IER           (0x00000028/4) /* Interrupt Enable reg */
53 #define GEM_IDR           (0x0000002C/4) /* Interrupt Disable reg */
54 #define GEM_IMR           (0x00000030/4) /* Interrupt Mask reg */
55 #define GEM_PHYMNTNC      (0x00000034/4) /* Phy Maintenance reg */
56 #define GEM_RXPAUSE       (0x00000038/4) /* RX Pause Time reg */
57 #define GEM_TXPAUSE       (0x0000003C/4) /* TX Pause Time reg */
58 #define GEM_TXPARTIALSF   (0x00000040/4) /* TX Partial Store and Forward */
59 #define GEM_RXPARTIALSF   (0x00000044/4) /* RX Partial Store and Forward */
60 #define GEM_HASHLO        (0x00000080/4) /* Hash Low address reg */
61 #define GEM_HASHHI        (0x00000084/4) /* Hash High address reg */
62 #define GEM_SPADDR1LO     (0x00000088/4) /* Specific addr 1 low reg */
63 #define GEM_SPADDR1HI     (0x0000008C/4) /* Specific addr 1 high reg */
64 #define GEM_SPADDR2LO     (0x00000090/4) /* Specific addr 2 low reg */
65 #define GEM_SPADDR2HI     (0x00000094/4) /* Specific addr 2 high reg */
66 #define GEM_SPADDR3LO     (0x00000098/4) /* Specific addr 3 low reg */
67 #define GEM_SPADDR3HI     (0x0000009C/4) /* Specific addr 3 high reg */
68 #define GEM_SPADDR4LO     (0x000000A0/4) /* Specific addr 4 low reg */
69 #define GEM_SPADDR4HI     (0x000000A4/4) /* Specific addr 4 high reg */
70 #define GEM_TIDMATCH1     (0x000000A8/4) /* Type ID1 Match reg */
71 #define GEM_TIDMATCH2     (0x000000AC/4) /* Type ID2 Match reg */
72 #define GEM_TIDMATCH3     (0x000000B0/4) /* Type ID3 Match reg */
73 #define GEM_TIDMATCH4     (0x000000B4/4) /* Type ID4 Match reg */
74 #define GEM_WOLAN         (0x000000B8/4) /* Wake on LAN reg */
75 #define GEM_IPGSTRETCH    (0x000000BC/4) /* IPG Stretch reg */
76 #define GEM_SVLAN         (0x000000C0/4) /* Stacked VLAN reg */
77 #define GEM_MODID         (0x000000FC/4) /* Module ID reg */
78 #define GEM_OCTTXLO       (0x00000100/4) /* Octects transmitted Low reg */
79 #define GEM_OCTTXHI       (0x00000104/4) /* Octects transmitted High reg */
80 #define GEM_TXCNT         (0x00000108/4) /* Error-free Frames transmitted */
81 #define GEM_TXBCNT        (0x0000010C/4) /* Error-free Broadcast Frames */
82 #define GEM_TXMCNT        (0x00000110/4) /* Error-free Multicast Frame */
83 #define GEM_TXPAUSECNT    (0x00000114/4) /* Pause Frames Transmitted */
84 #define GEM_TX64CNT       (0x00000118/4) /* Error-free 64 TX */
85 #define GEM_TX65CNT       (0x0000011C/4) /* Error-free 65-127 TX */
86 #define GEM_TX128CNT      (0x00000120/4) /* Error-free 128-255 TX */
87 #define GEM_TX256CNT      (0x00000124/4) /* Error-free 256-511 */
88 #define GEM_TX512CNT      (0x00000128/4) /* Error-free 512-1023 TX */
89 #define GEM_TX1024CNT     (0x0000012C/4) /* Error-free 1024-1518 TX */
90 #define GEM_TX1519CNT     (0x00000130/4) /* Error-free larger than 1519 TX */
91 #define GEM_TXURUNCNT     (0x00000134/4) /* TX under run error counter */
92 #define GEM_SINGLECOLLCNT (0x00000138/4) /* Single Collision Frames */
93 #define GEM_MULTCOLLCNT   (0x0000013C/4) /* Multiple Collision Frames */
94 #define GEM_EXCESSCOLLCNT (0x00000140/4) /* Excessive Collision Frames */
95 #define GEM_LATECOLLCNT   (0x00000144/4) /* Late Collision Frames */
96 #define GEM_DEFERTXCNT    (0x00000148/4) /* Deferred Transmission Frames */
97 #define GEM_CSENSECNT     (0x0000014C/4) /* Carrier Sense Error Counter */
98 #define GEM_OCTRXLO       (0x00000150/4) /* Octects Received register Low */
99 #define GEM_OCTRXHI       (0x00000154/4) /* Octects Received register High */
100 #define GEM_RXCNT         (0x00000158/4) /* Error-free Frames Received */
101 #define GEM_RXBROADCNT    (0x0000015C/4) /* Error-free Broadcast Frames RX */
102 #define GEM_RXMULTICNT    (0x00000160/4) /* Error-free Multicast Frames RX */
103 #define GEM_RXPAUSECNT    (0x00000164/4) /* Pause Frames Received Counter */
104 #define GEM_RX64CNT       (0x00000168/4) /* Error-free 64 byte Frames RX */
105 #define GEM_RX65CNT       (0x0000016C/4) /* Error-free 65-127B Frames RX */
106 #define GEM_RX128CNT      (0x00000170/4) /* Error-free 128-255B Frames RX */
107 #define GEM_RX256CNT      (0x00000174/4) /* Error-free 256-512B Frames RX */
108 #define GEM_RX512CNT      (0x00000178/4) /* Error-free 512-1023B Frames RX */
109 #define GEM_RX1024CNT     (0x0000017C/4) /* Error-free 1024-1518B Frames RX */
110 #define GEM_RX1519CNT     (0x00000180/4) /* Error-free 1519-max Frames RX */
111 #define GEM_RXUNDERCNT    (0x00000184/4) /* Undersize Frames Received */
112 #define GEM_RXOVERCNT     (0x00000188/4) /* Oversize Frames Received */
113 #define GEM_RXJABCNT      (0x0000018C/4) /* Jabbers Received Counter */
114 #define GEM_RXFCSCNT      (0x00000190/4) /* Frame Check seq. Error Counter */
115 #define GEM_RXLENERRCNT   (0x00000194/4) /* Length Field Error Counter */
116 #define GEM_RXSYMERRCNT   (0x00000198/4) /* Symbol Error Counter */
117 #define GEM_RXALIGNERRCNT (0x0000019C/4) /* Alignment Error Counter */
118 #define GEM_RXRSCERRCNT   (0x000001A0/4) /* Receive Resource Error Counter */
119 #define GEM_RXORUNCNT     (0x000001A4/4) /* Receive Overrun Counter */
120 #define GEM_RXIPCSERRCNT  (0x000001A8/4) /* IP header Checksum Error Counter */
121 #define GEM_RXTCPCCNT     (0x000001AC/4) /* TCP Checksum Error Counter */
122 #define GEM_RXUDPCCNT     (0x000001B0/4) /* UDP Checksum Error Counter */
123 
124 #define GEM_1588S         (0x000001D0/4) /* 1588 Timer Seconds */
125 #define GEM_1588NS        (0x000001D4/4) /* 1588 Timer Nanoseconds */
126 #define GEM_1588ADJ       (0x000001D8/4) /* 1588 Timer Adjust */
127 #define GEM_1588INC       (0x000001DC/4) /* 1588 Timer Increment */
128 #define GEM_PTPETXS       (0x000001E0/4) /* PTP Event Frame Transmitted (s) */
129 #define GEM_PTPETXNS      (0x000001E4/4) /* PTP Event Frame Transmitted (ns) */
130 #define GEM_PTPERXS       (0x000001E8/4) /* PTP Event Frame Received (s) */
131 #define GEM_PTPERXNS      (0x000001EC/4) /* PTP Event Frame Received (ns) */
132 #define GEM_PTPPTXS       (0x000001E0/4) /* PTP Peer Frame Transmitted (s) */
133 #define GEM_PTPPTXNS      (0x000001E4/4) /* PTP Peer Frame Transmitted (ns) */
134 #define GEM_PTPPRXS       (0x000001E8/4) /* PTP Peer Frame Received (s) */
135 #define GEM_PTPPRXNS      (0x000001EC/4) /* PTP Peer Frame Received (ns) */
136 
137 /* Design Configuration Registers */
138 #define GEM_DESCONF       (0x00000280/4)
139 #define GEM_DESCONF2      (0x00000284/4)
140 #define GEM_DESCONF3      (0x00000288/4)
141 #define GEM_DESCONF4      (0x0000028C/4)
142 #define GEM_DESCONF5      (0x00000290/4)
143 #define GEM_DESCONF6      (0x00000294/4)
144 #define GEM_DESCONF7      (0x00000298/4)
145 
146 #define GEM_INT_Q1_STATUS               (0x00000400 / 4)
147 #define GEM_INT_Q1_MASK                 (0x00000640 / 4)
148 
149 #define GEM_TRANSMIT_Q1_PTR             (0x00000440 / 4)
150 #define GEM_TRANSMIT_Q7_PTR             (GEM_TRANSMIT_Q1_PTR + 6)
151 
152 #define GEM_RECEIVE_Q1_PTR              (0x00000480 / 4)
153 #define GEM_RECEIVE_Q7_PTR              (GEM_RECEIVE_Q1_PTR + 6)
154 
155 #define GEM_INT_Q1_ENABLE               (0x00000600 / 4)
156 #define GEM_INT_Q7_ENABLE               (GEM_INT_Q1_ENABLE + 6)
157 
158 #define GEM_INT_Q1_DISABLE              (0x00000620 / 4)
159 #define GEM_INT_Q7_DISABLE              (GEM_INT_Q1_DISABLE + 6)
160 
161 #define GEM_INT_Q1_MASK                 (0x00000640 / 4)
162 #define GEM_INT_Q7_MASK                 (GEM_INT_Q1_MASK + 6)
163 
164 #define GEM_SCREENING_TYPE1_REGISTER_0  (0x00000500 / 4)
165 
166 #define GEM_ST1R_UDP_PORT_MATCH_ENABLE  (1 << 29)
167 #define GEM_ST1R_DSTC_ENABLE            (1 << 28)
168 #define GEM_ST1R_UDP_PORT_MATCH_SHIFT   (12)
169 #define GEM_ST1R_UDP_PORT_MATCH_WIDTH   (27 - GEM_ST1R_UDP_PORT_MATCH_SHIFT + 1)
170 #define GEM_ST1R_DSTC_MATCH_SHIFT       (4)
171 #define GEM_ST1R_DSTC_MATCH_WIDTH       (11 - GEM_ST1R_DSTC_MATCH_SHIFT + 1)
172 #define GEM_ST1R_QUEUE_SHIFT            (0)
173 #define GEM_ST1R_QUEUE_WIDTH            (3 - GEM_ST1R_QUEUE_SHIFT + 1)
174 
175 #define GEM_SCREENING_TYPE2_REGISTER_0  (0x00000540 / 4)
176 
177 #define GEM_ST2R_COMPARE_A_ENABLE       (1 << 18)
178 #define GEM_ST2R_COMPARE_A_SHIFT        (13)
179 #define GEM_ST2R_COMPARE_WIDTH          (17 - GEM_ST2R_COMPARE_A_SHIFT + 1)
180 #define GEM_ST2R_ETHERTYPE_ENABLE       (1 << 12)
181 #define GEM_ST2R_ETHERTYPE_INDEX_SHIFT  (9)
182 #define GEM_ST2R_ETHERTYPE_INDEX_WIDTH  (11 - GEM_ST2R_ETHERTYPE_INDEX_SHIFT \
183                                             + 1)
184 #define GEM_ST2R_QUEUE_SHIFT            (0)
185 #define GEM_ST2R_QUEUE_WIDTH            (3 - GEM_ST2R_QUEUE_SHIFT + 1)
186 
187 #define GEM_SCREENING_TYPE2_ETHERTYPE_REG_0     (0x000006e0 / 4)
188 #define GEM_TYPE2_COMPARE_0_WORD_0              (0x00000700 / 4)
189 
190 #define GEM_T2CW1_COMPARE_OFFSET_SHIFT  (7)
191 #define GEM_T2CW1_COMPARE_OFFSET_WIDTH  (8 - GEM_T2CW1_COMPARE_OFFSET_SHIFT + 1)
192 #define GEM_T2CW1_OFFSET_VALUE_SHIFT    (0)
193 #define GEM_T2CW1_OFFSET_VALUE_WIDTH    (6 - GEM_T2CW1_OFFSET_VALUE_SHIFT + 1)
194 
195 /*****************************************/
196 #define GEM_NWCTRL_TXSTART     0x00000200 /* Transmit Enable */
197 #define GEM_NWCTRL_TXENA       0x00000008 /* Transmit Enable */
198 #define GEM_NWCTRL_RXENA       0x00000004 /* Receive Enable */
199 #define GEM_NWCTRL_LOCALLOOP   0x00000002 /* Local Loopback */
200 
201 #define GEM_NWCFG_STRIP_FCS    0x00020000 /* Strip FCS field */
202 #define GEM_NWCFG_LERR_DISC    0x00010000 /* Discard RX frames with len err */
203 #define GEM_NWCFG_BUFF_OFST_M  0x0000C000 /* Receive buffer offset mask */
204 #define GEM_NWCFG_BUFF_OFST_S  14         /* Receive buffer offset shift */
205 #define GEM_NWCFG_UCAST_HASH   0x00000080 /* accept unicast if hash match */
206 #define GEM_NWCFG_MCAST_HASH   0x00000040 /* accept multicast if hash match */
207 #define GEM_NWCFG_BCAST_REJ    0x00000020 /* Reject broadcast packets */
208 #define GEM_NWCFG_PROMISC      0x00000010 /* Accept all packets */
209 
210 #define GEM_DMACFG_RBUFSZ_M    0x00FF0000 /* DMA RX Buffer Size mask */
211 #define GEM_DMACFG_RBUFSZ_S    16         /* DMA RX Buffer Size shift */
212 #define GEM_DMACFG_RBUFSZ_MUL  64         /* DMA RX Buffer Size multiplier */
213 #define GEM_DMACFG_TXCSUM_OFFL 0x00000800 /* Transmit checksum offload */
214 
215 #define GEM_TXSTATUS_TXCMPL    0x00000020 /* Transmit Complete */
216 #define GEM_TXSTATUS_USED      0x00000001 /* sw owned descriptor encountered */
217 
218 #define GEM_RXSTATUS_FRMRCVD   0x00000002 /* Frame received */
219 #define GEM_RXSTATUS_NOBUF     0x00000001 /* Buffer unavailable */
220 
221 /* GEM_ISR GEM_IER GEM_IDR GEM_IMR */
222 #define GEM_INT_TXCMPL        0x00000080 /* Transmit Complete */
223 #define GEM_INT_TXUSED         0x00000008
224 #define GEM_INT_RXUSED         0x00000004
225 #define GEM_INT_RXCMPL        0x00000002
226 
227 #define GEM_PHYMNTNC_OP_R      0x20000000 /* read operation */
228 #define GEM_PHYMNTNC_OP_W      0x10000000 /* write operation */
229 #define GEM_PHYMNTNC_ADDR      0x0F800000 /* Address bits */
230 #define GEM_PHYMNTNC_ADDR_SHFT 23
231 #define GEM_PHYMNTNC_REG       0x007C0000 /* register bits */
232 #define GEM_PHYMNTNC_REG_SHIFT 18
233 
234 /* Marvell PHY definitions */
235 #define BOARD_PHY_ADDRESS    23 /* PHY address we will emulate a device at */
236 
237 #define PHY_REG_CONTROL      0
238 #define PHY_REG_STATUS       1
239 #define PHY_REG_PHYID1       2
240 #define PHY_REG_PHYID2       3
241 #define PHY_REG_ANEGADV      4
242 #define PHY_REG_LINKPABIL    5
243 #define PHY_REG_ANEGEXP      6
244 #define PHY_REG_NEXTP        7
245 #define PHY_REG_LINKPNEXTP   8
246 #define PHY_REG_100BTCTRL    9
247 #define PHY_REG_1000BTSTAT   10
248 #define PHY_REG_EXTSTAT      15
249 #define PHY_REG_PHYSPCFC_CTL 16
250 #define PHY_REG_PHYSPCFC_ST  17
251 #define PHY_REG_INT_EN       18
252 #define PHY_REG_INT_ST       19
253 #define PHY_REG_EXT_PHYSPCFC_CTL  20
254 #define PHY_REG_RXERR        21
255 #define PHY_REG_EACD         22
256 #define PHY_REG_LED          24
257 #define PHY_REG_LED_OVRD     25
258 #define PHY_REG_EXT_PHYSPCFC_CTL2 26
259 #define PHY_REG_EXT_PHYSPCFC_ST   27
260 #define PHY_REG_CABLE_DIAG   28
261 
262 #define PHY_REG_CONTROL_RST  0x8000
263 #define PHY_REG_CONTROL_LOOP 0x4000
264 #define PHY_REG_CONTROL_ANEG 0x1000
265 
266 #define PHY_REG_STATUS_LINK     0x0004
267 #define PHY_REG_STATUS_ANEGCMPL 0x0020
268 
269 #define PHY_REG_INT_ST_ANEGCMPL 0x0800
270 #define PHY_REG_INT_ST_LINKC    0x0400
271 #define PHY_REG_INT_ST_ENERGY   0x0010
272 
273 /***********************************************************************/
274 #define GEM_RX_REJECT                   (-1)
275 #define GEM_RX_PROMISCUOUS_ACCEPT       (-2)
276 #define GEM_RX_BROADCAST_ACCEPT         (-3)
277 #define GEM_RX_MULTICAST_HASH_ACCEPT    (-4)
278 #define GEM_RX_UNICAST_HASH_ACCEPT      (-5)
279 
280 #define GEM_RX_SAR_ACCEPT               0
281 
282 /***********************************************************************/
283 
284 #define DESC_1_USED 0x80000000
285 #define DESC_1_LENGTH 0x00001FFF
286 
287 #define DESC_1_TX_WRAP 0x40000000
288 #define DESC_1_TX_LAST 0x00008000
289 
290 #define DESC_0_RX_WRAP 0x00000002
291 #define DESC_0_RX_OWNERSHIP 0x00000001
292 
293 #define R_DESC_1_RX_SAR_SHIFT           25
294 #define R_DESC_1_RX_SAR_LENGTH          2
295 #define R_DESC_1_RX_SAR_MATCH           (1 << 27)
296 #define R_DESC_1_RX_UNICAST_HASH        (1 << 29)
297 #define R_DESC_1_RX_MULTICAST_HASH      (1 << 30)
298 #define R_DESC_1_RX_BROADCAST           (1 << 31)
299 
300 #define DESC_1_RX_SOF 0x00004000
301 #define DESC_1_RX_EOF 0x00008000
302 
303 static inline unsigned tx_desc_get_buffer(unsigned *desc)
304 {
305     return desc[0];
306 }
307 
308 static inline unsigned tx_desc_get_used(unsigned *desc)
309 {
310     return (desc[1] & DESC_1_USED) ? 1 : 0;
311 }
312 
313 static inline void tx_desc_set_used(unsigned *desc)
314 {
315     desc[1] |= DESC_1_USED;
316 }
317 
318 static inline unsigned tx_desc_get_wrap(unsigned *desc)
319 {
320     return (desc[1] & DESC_1_TX_WRAP) ? 1 : 0;
321 }
322 
323 static inline unsigned tx_desc_get_last(unsigned *desc)
324 {
325     return (desc[1] & DESC_1_TX_LAST) ? 1 : 0;
326 }
327 
328 static inline void tx_desc_set_last(unsigned *desc)
329 {
330     desc[1] |= DESC_1_TX_LAST;
331 }
332 
333 static inline unsigned tx_desc_get_length(unsigned *desc)
334 {
335     return desc[1] & DESC_1_LENGTH;
336 }
337 
338 static inline void print_gem_tx_desc(unsigned *desc, uint8_t queue)
339 {
340     DB_PRINT("TXDESC (queue %" PRId8 "):\n", queue);
341     DB_PRINT("bufaddr: 0x%08x\n", *desc);
342     DB_PRINT("used_hw: %d\n", tx_desc_get_used(desc));
343     DB_PRINT("wrap:    %d\n", tx_desc_get_wrap(desc));
344     DB_PRINT("last:    %d\n", tx_desc_get_last(desc));
345     DB_PRINT("length:  %d\n", tx_desc_get_length(desc));
346 }
347 
348 static inline unsigned rx_desc_get_buffer(unsigned *desc)
349 {
350     return desc[0] & ~0x3UL;
351 }
352 
353 static inline unsigned rx_desc_get_wrap(unsigned *desc)
354 {
355     return desc[0] & DESC_0_RX_WRAP ? 1 : 0;
356 }
357 
358 static inline unsigned rx_desc_get_ownership(unsigned *desc)
359 {
360     return desc[0] & DESC_0_RX_OWNERSHIP ? 1 : 0;
361 }
362 
363 static inline void rx_desc_set_ownership(unsigned *desc)
364 {
365     desc[0] |= DESC_0_RX_OWNERSHIP;
366 }
367 
368 static inline void rx_desc_set_sof(unsigned *desc)
369 {
370     desc[1] |= DESC_1_RX_SOF;
371 }
372 
373 static inline void rx_desc_set_eof(unsigned *desc)
374 {
375     desc[1] |= DESC_1_RX_EOF;
376 }
377 
378 static inline void rx_desc_set_length(unsigned *desc, unsigned len)
379 {
380     desc[1] &= ~DESC_1_LENGTH;
381     desc[1] |= len;
382 }
383 
384 static inline void rx_desc_set_broadcast(unsigned *desc)
385 {
386     desc[1] |= R_DESC_1_RX_BROADCAST;
387 }
388 
389 static inline void rx_desc_set_unicast_hash(unsigned *desc)
390 {
391     desc[1] |= R_DESC_1_RX_UNICAST_HASH;
392 }
393 
394 static inline void rx_desc_set_multicast_hash(unsigned *desc)
395 {
396     desc[1] |= R_DESC_1_RX_MULTICAST_HASH;
397 }
398 
399 static inline void rx_desc_set_sar(unsigned *desc, int sar_idx)
400 {
401     desc[1] = deposit32(desc[1], R_DESC_1_RX_SAR_SHIFT, R_DESC_1_RX_SAR_LENGTH,
402                         sar_idx);
403     desc[1] |= R_DESC_1_RX_SAR_MATCH;
404 }
405 
406 /* The broadcast MAC address: 0xFFFFFFFFFFFF */
407 static const uint8_t broadcast_addr[] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
408 
409 /*
410  * gem_init_register_masks:
411  * One time initialization.
412  * Set masks to identify which register bits have magical clear properties
413  */
414 static void gem_init_register_masks(CadenceGEMState *s)
415 {
416     /* Mask of register bits which are read only */
417     memset(&s->regs_ro[0], 0, sizeof(s->regs_ro));
418     s->regs_ro[GEM_NWCTRL]   = 0xFFF80000;
419     s->regs_ro[GEM_NWSTATUS] = 0xFFFFFFFF;
420     s->regs_ro[GEM_DMACFG]   = 0xFE00F000;
421     s->regs_ro[GEM_TXSTATUS] = 0xFFFFFE08;
422     s->regs_ro[GEM_RXQBASE]  = 0x00000003;
423     s->regs_ro[GEM_TXQBASE]  = 0x00000003;
424     s->regs_ro[GEM_RXSTATUS] = 0xFFFFFFF0;
425     s->regs_ro[GEM_ISR]      = 0xFFFFFFFF;
426     s->regs_ro[GEM_IMR]      = 0xFFFFFFFF;
427     s->regs_ro[GEM_MODID]    = 0xFFFFFFFF;
428 
429     /* Mask of register bits which are clear on read */
430     memset(&s->regs_rtc[0], 0, sizeof(s->regs_rtc));
431     s->regs_rtc[GEM_ISR]      = 0xFFFFFFFF;
432 
433     /* Mask of register bits which are write 1 to clear */
434     memset(&s->regs_w1c[0], 0, sizeof(s->regs_w1c));
435     s->regs_w1c[GEM_TXSTATUS] = 0x000001F7;
436     s->regs_w1c[GEM_RXSTATUS] = 0x0000000F;
437 
438     /* Mask of register bits which are write only */
439     memset(&s->regs_wo[0], 0, sizeof(s->regs_wo));
440     s->regs_wo[GEM_NWCTRL]   = 0x00073E60;
441     s->regs_wo[GEM_IER]      = 0x07FFFFFF;
442     s->regs_wo[GEM_IDR]      = 0x07FFFFFF;
443 }
444 
445 /*
446  * phy_update_link:
447  * Make the emulated PHY link state match the QEMU "interface" state.
448  */
449 static void phy_update_link(CadenceGEMState *s)
450 {
451     DB_PRINT("down %d\n", qemu_get_queue(s->nic)->link_down);
452 
453     /* Autonegotiation status mirrors link status.  */
454     if (qemu_get_queue(s->nic)->link_down) {
455         s->phy_regs[PHY_REG_STATUS] &= ~(PHY_REG_STATUS_ANEGCMPL |
456                                          PHY_REG_STATUS_LINK);
457         s->phy_regs[PHY_REG_INT_ST] |= PHY_REG_INT_ST_LINKC;
458     } else {
459         s->phy_regs[PHY_REG_STATUS] |= (PHY_REG_STATUS_ANEGCMPL |
460                                          PHY_REG_STATUS_LINK);
461         s->phy_regs[PHY_REG_INT_ST] |= (PHY_REG_INT_ST_LINKC |
462                                         PHY_REG_INT_ST_ANEGCMPL |
463                                         PHY_REG_INT_ST_ENERGY);
464     }
465 }
466 
467 static int gem_can_receive(NetClientState *nc)
468 {
469     CadenceGEMState *s;
470     int i;
471 
472     s = qemu_get_nic_opaque(nc);
473 
474     /* Do nothing if receive is not enabled. */
475     if (!(s->regs[GEM_NWCTRL] & GEM_NWCTRL_RXENA)) {
476         if (s->can_rx_state != 1) {
477             s->can_rx_state = 1;
478             DB_PRINT("can't receive - no enable\n");
479         }
480         return 0;
481     }
482 
483     for (i = 0; i < s->num_priority_queues; i++) {
484         if (rx_desc_get_ownership(s->rx_desc[i]) == 1) {
485             if (s->can_rx_state != 2) {
486                 s->can_rx_state = 2;
487                 DB_PRINT("can't receive - busy buffer descriptor (q%d) 0x%x\n",
488                          i, s->rx_desc_addr[i]);
489              }
490             return 0;
491         }
492     }
493 
494     if (s->can_rx_state != 0) {
495         s->can_rx_state = 0;
496         DB_PRINT("can receive\n");
497     }
498     return 1;
499 }
500 
501 /*
502  * gem_update_int_status:
503  * Raise or lower interrupt based on current status.
504  */
505 static void gem_update_int_status(CadenceGEMState *s)
506 {
507     int i;
508 
509     if ((s->num_priority_queues == 1) && s->regs[GEM_ISR]) {
510         /* No priority queues, just trigger the interrupt */
511         DB_PRINT("asserting int.\n", i);
512         qemu_set_irq(s->irq[0], 1);
513         return;
514     }
515 
516     for (i = 0; i < s->num_priority_queues; ++i) {
517         if (s->regs[GEM_INT_Q1_STATUS + i]) {
518             DB_PRINT("asserting int. (q=%d)\n", i);
519             qemu_set_irq(s->irq[i], 1);
520         }
521     }
522 }
523 
524 /*
525  * gem_receive_updatestats:
526  * Increment receive statistics.
527  */
528 static void gem_receive_updatestats(CadenceGEMState *s, const uint8_t *packet,
529                                     unsigned bytes)
530 {
531     uint64_t octets;
532 
533     /* Total octets (bytes) received */
534     octets = ((uint64_t)(s->regs[GEM_OCTRXLO]) << 32) |
535              s->regs[GEM_OCTRXHI];
536     octets += bytes;
537     s->regs[GEM_OCTRXLO] = octets >> 32;
538     s->regs[GEM_OCTRXHI] = octets;
539 
540     /* Error-free Frames received */
541     s->regs[GEM_RXCNT]++;
542 
543     /* Error-free Broadcast Frames counter */
544     if (!memcmp(packet, broadcast_addr, 6)) {
545         s->regs[GEM_RXBROADCNT]++;
546     }
547 
548     /* Error-free Multicast Frames counter */
549     if (packet[0] == 0x01) {
550         s->regs[GEM_RXMULTICNT]++;
551     }
552 
553     if (bytes <= 64) {
554         s->regs[GEM_RX64CNT]++;
555     } else if (bytes <= 127) {
556         s->regs[GEM_RX65CNT]++;
557     } else if (bytes <= 255) {
558         s->regs[GEM_RX128CNT]++;
559     } else if (bytes <= 511) {
560         s->regs[GEM_RX256CNT]++;
561     } else if (bytes <= 1023) {
562         s->regs[GEM_RX512CNT]++;
563     } else if (bytes <= 1518) {
564         s->regs[GEM_RX1024CNT]++;
565     } else {
566         s->regs[GEM_RX1519CNT]++;
567     }
568 }
569 
570 /*
571  * Get the MAC Address bit from the specified position
572  */
573 static unsigned get_bit(const uint8_t *mac, unsigned bit)
574 {
575     unsigned byte;
576 
577     byte = mac[bit / 8];
578     byte >>= (bit & 0x7);
579     byte &= 1;
580 
581     return byte;
582 }
583 
584 /*
585  * Calculate a GEM MAC Address hash index
586  */
587 static unsigned calc_mac_hash(const uint8_t *mac)
588 {
589     int index_bit, mac_bit;
590     unsigned hash_index;
591 
592     hash_index = 0;
593     mac_bit = 5;
594     for (index_bit = 5; index_bit >= 0; index_bit--) {
595         hash_index |= (get_bit(mac,  mac_bit) ^
596                                get_bit(mac, mac_bit + 6) ^
597                                get_bit(mac, mac_bit + 12) ^
598                                get_bit(mac, mac_bit + 18) ^
599                                get_bit(mac, mac_bit + 24) ^
600                                get_bit(mac, mac_bit + 30) ^
601                                get_bit(mac, mac_bit + 36) ^
602                                get_bit(mac, mac_bit + 42)) << index_bit;
603         mac_bit--;
604     }
605 
606     return hash_index;
607 }
608 
609 /*
610  * gem_mac_address_filter:
611  * Accept or reject this destination address?
612  * Returns:
613  * GEM_RX_REJECT: reject
614  * >= 0: Specific address accept (which matched SAR is returned)
615  * others for various other modes of accept:
616  * GEM_RM_PROMISCUOUS_ACCEPT, GEM_RX_BROADCAST_ACCEPT,
617  * GEM_RX_MULTICAST_HASH_ACCEPT or GEM_RX_UNICAST_HASH_ACCEPT
618  */
619 static int gem_mac_address_filter(CadenceGEMState *s, const uint8_t *packet)
620 {
621     uint8_t *gem_spaddr;
622     int i;
623 
624     /* Promiscuous mode? */
625     if (s->regs[GEM_NWCFG] & GEM_NWCFG_PROMISC) {
626         return GEM_RX_PROMISCUOUS_ACCEPT;
627     }
628 
629     if (!memcmp(packet, broadcast_addr, 6)) {
630         /* Reject broadcast packets? */
631         if (s->regs[GEM_NWCFG] & GEM_NWCFG_BCAST_REJ) {
632             return GEM_RX_REJECT;
633         }
634         return GEM_RX_BROADCAST_ACCEPT;
635     }
636 
637     /* Accept packets -w- hash match? */
638     if ((packet[0] == 0x01 && (s->regs[GEM_NWCFG] & GEM_NWCFG_MCAST_HASH)) ||
639         (packet[0] != 0x01 && (s->regs[GEM_NWCFG] & GEM_NWCFG_UCAST_HASH))) {
640         unsigned hash_index;
641 
642         hash_index = calc_mac_hash(packet);
643         if (hash_index < 32) {
644             if (s->regs[GEM_HASHLO] & (1<<hash_index)) {
645                 return packet[0] == 0x01 ? GEM_RX_MULTICAST_HASH_ACCEPT :
646                                            GEM_RX_UNICAST_HASH_ACCEPT;
647             }
648         } else {
649             hash_index -= 32;
650             if (s->regs[GEM_HASHHI] & (1<<hash_index)) {
651                 return packet[0] == 0x01 ? GEM_RX_MULTICAST_HASH_ACCEPT :
652                                            GEM_RX_UNICAST_HASH_ACCEPT;
653             }
654         }
655     }
656 
657     /* Check all 4 specific addresses */
658     gem_spaddr = (uint8_t *)&(s->regs[GEM_SPADDR1LO]);
659     for (i = 3; i >= 0; i--) {
660         if (s->sar_active[i] && !memcmp(packet, gem_spaddr + 8 * i, 6)) {
661             return GEM_RX_SAR_ACCEPT + i;
662         }
663     }
664 
665     /* No address match; reject the packet */
666     return GEM_RX_REJECT;
667 }
668 
669 /* Figure out which queue the received data should be sent to */
670 static int get_queue_from_screen(CadenceGEMState *s, uint8_t *rxbuf_ptr,
671                                  unsigned rxbufsize)
672 {
673     uint32_t reg;
674     bool matched, mismatched;
675     int i, j;
676 
677     for (i = 0; i < s->num_type1_screeners; i++) {
678         reg = s->regs[GEM_SCREENING_TYPE1_REGISTER_0 + i];
679         matched = false;
680         mismatched = false;
681 
682         /* Screening is based on UDP Port */
683         if (reg & GEM_ST1R_UDP_PORT_MATCH_ENABLE) {
684             uint16_t udp_port = rxbuf_ptr[14 + 22] << 8 | rxbuf_ptr[14 + 23];
685             if (udp_port == extract32(reg, GEM_ST1R_UDP_PORT_MATCH_SHIFT,
686                                            GEM_ST1R_UDP_PORT_MATCH_WIDTH)) {
687                 matched = true;
688             } else {
689                 mismatched = true;
690             }
691         }
692 
693         /* Screening is based on DS/TC */
694         if (reg & GEM_ST1R_DSTC_ENABLE) {
695             uint8_t dscp = rxbuf_ptr[14 + 1];
696             if (dscp == extract32(reg, GEM_ST1R_DSTC_MATCH_SHIFT,
697                                        GEM_ST1R_DSTC_MATCH_WIDTH)) {
698                 matched = true;
699             } else {
700                 mismatched = true;
701             }
702         }
703 
704         if (matched && !mismatched) {
705             return extract32(reg, GEM_ST1R_QUEUE_SHIFT, GEM_ST1R_QUEUE_WIDTH);
706         }
707     }
708 
709     for (i = 0; i < s->num_type2_screeners; i++) {
710         reg = s->regs[GEM_SCREENING_TYPE2_REGISTER_0 + i];
711         matched = false;
712         mismatched = false;
713 
714         if (reg & GEM_ST2R_ETHERTYPE_ENABLE) {
715             uint16_t type = rxbuf_ptr[12] << 8 | rxbuf_ptr[13];
716             int et_idx = extract32(reg, GEM_ST2R_ETHERTYPE_INDEX_SHIFT,
717                                         GEM_ST2R_ETHERTYPE_INDEX_WIDTH);
718 
719             if (et_idx > s->num_type2_screeners) {
720                 qemu_log_mask(LOG_GUEST_ERROR, "Out of range ethertype "
721                               "register index: %d\n", et_idx);
722             }
723             if (type == s->regs[GEM_SCREENING_TYPE2_ETHERTYPE_REG_0 +
724                                 et_idx]) {
725                 matched = true;
726             } else {
727                 mismatched = true;
728             }
729         }
730 
731         /* Compare A, B, C */
732         for (j = 0; j < 3; j++) {
733             uint32_t cr0, cr1, mask;
734             uint16_t rx_cmp;
735             int offset;
736             int cr_idx = extract32(reg, GEM_ST2R_COMPARE_A_SHIFT + j * 6,
737                                         GEM_ST2R_COMPARE_WIDTH);
738 
739             if (!(reg & (GEM_ST2R_COMPARE_A_ENABLE << (j * 6)))) {
740                 continue;
741             }
742             if (cr_idx > s->num_type2_screeners) {
743                 qemu_log_mask(LOG_GUEST_ERROR, "Out of range compare "
744                               "register index: %d\n", cr_idx);
745             }
746 
747             cr0 = s->regs[GEM_TYPE2_COMPARE_0_WORD_0 + cr_idx * 2];
748             cr1 = s->regs[GEM_TYPE2_COMPARE_0_WORD_0 + cr_idx * 2 + 1];
749             offset = extract32(cr1, GEM_T2CW1_OFFSET_VALUE_SHIFT,
750                                     GEM_T2CW1_OFFSET_VALUE_WIDTH);
751 
752             switch (extract32(cr1, GEM_T2CW1_COMPARE_OFFSET_SHIFT,
753                                    GEM_T2CW1_COMPARE_OFFSET_WIDTH)) {
754             case 3: /* Skip UDP header */
755                 qemu_log_mask(LOG_UNIMP, "TCP compare offsets"
756                               "unimplemented - assuming UDP\n");
757                 offset += 8;
758                 /* Fallthrough */
759             case 2: /* skip the IP header */
760                 offset += 20;
761                 /* Fallthrough */
762             case 1: /* Count from after the ethertype */
763                 offset += 14;
764                 break;
765             case 0:
766                 /* Offset from start of frame */
767                 break;
768             }
769 
770             rx_cmp = rxbuf_ptr[offset] << 8 | rxbuf_ptr[offset];
771             mask = extract32(cr0, 0, 16);
772 
773             if ((rx_cmp & mask) == (extract32(cr0, 16, 16) & mask)) {
774                 matched = true;
775             } else {
776                 mismatched = true;
777             }
778         }
779 
780         if (matched && !mismatched) {
781             return extract32(reg, GEM_ST2R_QUEUE_SHIFT, GEM_ST2R_QUEUE_WIDTH);
782         }
783     }
784 
785     /* We made it here, assume it's queue 0 */
786     return 0;
787 }
788 
789 static void gem_get_rx_desc(CadenceGEMState *s, int q)
790 {
791     DB_PRINT("read descriptor 0x%x\n", (unsigned)s->rx_desc_addr[q]);
792     /* read current descriptor */
793     cpu_physical_memory_read(s->rx_desc_addr[0],
794                              (uint8_t *)s->rx_desc[0], sizeof(s->rx_desc[0]));
795 
796     /* Descriptor owned by software ? */
797     if (rx_desc_get_ownership(s->rx_desc[q]) == 1) {
798         DB_PRINT("descriptor 0x%x owned by sw.\n",
799                  (unsigned)s->rx_desc_addr[q]);
800         s->regs[GEM_RXSTATUS] |= GEM_RXSTATUS_NOBUF;
801         s->regs[GEM_ISR] |= GEM_INT_RXUSED & ~(s->regs[GEM_IMR]);
802         /* Handle interrupt consequences */
803         gem_update_int_status(s);
804     }
805 }
806 
807 /*
808  * gem_receive:
809  * Fit a packet handed to us by QEMU into the receive descriptor ring.
810  */
811 static ssize_t gem_receive(NetClientState *nc, const uint8_t *buf, size_t size)
812 {
813     CadenceGEMState *s;
814     unsigned   rxbufsize, bytes_to_copy;
815     unsigned   rxbuf_offset;
816     uint8_t    rxbuf[2048];
817     uint8_t   *rxbuf_ptr;
818     bool first_desc = true;
819     int maf;
820     int q = 0;
821 
822     s = qemu_get_nic_opaque(nc);
823 
824     /* Is this destination MAC address "for us" ? */
825     maf = gem_mac_address_filter(s, buf);
826     if (maf == GEM_RX_REJECT) {
827         return -1;
828     }
829 
830     /* Discard packets with receive length error enabled ? */
831     if (s->regs[GEM_NWCFG] & GEM_NWCFG_LERR_DISC) {
832         unsigned type_len;
833 
834         /* Fish the ethertype / length field out of the RX packet */
835         type_len = buf[12] << 8 | buf[13];
836         /* It is a length field, not an ethertype */
837         if (type_len < 0x600) {
838             if (size < type_len) {
839                 /* discard */
840                 return -1;
841             }
842         }
843     }
844 
845     /*
846      * Determine configured receive buffer offset (probably 0)
847      */
848     rxbuf_offset = (s->regs[GEM_NWCFG] & GEM_NWCFG_BUFF_OFST_M) >>
849                    GEM_NWCFG_BUFF_OFST_S;
850 
851     /* The configure size of each receive buffer.  Determines how many
852      * buffers needed to hold this packet.
853      */
854     rxbufsize = ((s->regs[GEM_DMACFG] & GEM_DMACFG_RBUFSZ_M) >>
855                  GEM_DMACFG_RBUFSZ_S) * GEM_DMACFG_RBUFSZ_MUL;
856     bytes_to_copy = size;
857 
858     /* Hardware allows a zero value here but warns against it. To avoid QEMU
859      * indefinite loops we enforce a minimum value here
860      */
861     if (rxbufsize < GEM_DMACFG_RBUFSZ_MUL) {
862         rxbufsize = GEM_DMACFG_RBUFSZ_MUL;
863     }
864 
865     /* Pad to minimum length. Assume FCS field is stripped, logic
866      * below will increment it to the real minimum of 64 when
867      * not FCS stripping
868      */
869     if (size < 60) {
870         size = 60;
871     }
872 
873     /* Strip of FCS field ? (usually yes) */
874     if (s->regs[GEM_NWCFG] & GEM_NWCFG_STRIP_FCS) {
875         rxbuf_ptr = (void *)buf;
876     } else {
877         unsigned crc_val;
878 
879         if (size > sizeof(rxbuf) - sizeof(crc_val)) {
880             size = sizeof(rxbuf) - sizeof(crc_val);
881         }
882         bytes_to_copy = size;
883         /* The application wants the FCS field, which QEMU does not provide.
884          * We must try and calculate one.
885          */
886 
887         memcpy(rxbuf, buf, size);
888         memset(rxbuf + size, 0, sizeof(rxbuf) - size);
889         rxbuf_ptr = rxbuf;
890         crc_val = cpu_to_le32(crc32(0, rxbuf, MAX(size, 60)));
891         memcpy(rxbuf + size, &crc_val, sizeof(crc_val));
892 
893         bytes_to_copy += 4;
894         size += 4;
895     }
896 
897     DB_PRINT("config bufsize: %d packet size: %ld\n", rxbufsize, size);
898 
899     /* Find which queue we are targetting */
900     q = get_queue_from_screen(s, rxbuf_ptr, rxbufsize);
901 
902     while (bytes_to_copy) {
903         /* Do nothing if receive is not enabled. */
904         if (!gem_can_receive(nc)) {
905             assert(!first_desc);
906             return -1;
907         }
908 
909         DB_PRINT("copy %d bytes to 0x%x\n", MIN(bytes_to_copy, rxbufsize),
910                 rx_desc_get_buffer(s->rx_desc[q]));
911 
912         /* Copy packet data to emulated DMA buffer */
913         cpu_physical_memory_write(rx_desc_get_buffer(s->rx_desc[q]) +
914                                                                  rxbuf_offset,
915                                   rxbuf_ptr, MIN(bytes_to_copy, rxbufsize));
916         rxbuf_ptr += MIN(bytes_to_copy, rxbufsize);
917         bytes_to_copy -= MIN(bytes_to_copy, rxbufsize);
918 
919         /* Update the descriptor.  */
920         if (first_desc) {
921             rx_desc_set_sof(s->rx_desc[q]);
922             first_desc = false;
923         }
924         if (bytes_to_copy == 0) {
925             rx_desc_set_eof(s->rx_desc[q]);
926             rx_desc_set_length(s->rx_desc[q], size);
927         }
928         rx_desc_set_ownership(s->rx_desc[q]);
929 
930         switch (maf) {
931         case GEM_RX_PROMISCUOUS_ACCEPT:
932             break;
933         case GEM_RX_BROADCAST_ACCEPT:
934             rx_desc_set_broadcast(s->rx_desc[q]);
935             break;
936         case GEM_RX_UNICAST_HASH_ACCEPT:
937             rx_desc_set_unicast_hash(s->rx_desc[q]);
938             break;
939         case GEM_RX_MULTICAST_HASH_ACCEPT:
940             rx_desc_set_multicast_hash(s->rx_desc[q]);
941             break;
942         case GEM_RX_REJECT:
943             abort();
944         default: /* SAR */
945             rx_desc_set_sar(s->rx_desc[q], maf);
946         }
947 
948         /* Descriptor write-back.  */
949         cpu_physical_memory_write(s->rx_desc_addr[q],
950                                   (uint8_t *)s->rx_desc[q],
951                                   sizeof(s->rx_desc[q]));
952 
953         /* Next descriptor */
954         if (rx_desc_get_wrap(s->rx_desc[q])) {
955             DB_PRINT("wrapping RX descriptor list\n");
956             s->rx_desc_addr[q] = s->regs[GEM_RXQBASE];
957         } else {
958             DB_PRINT("incrementing RX descriptor list\n");
959             s->rx_desc_addr[q] += 8;
960         }
961 
962         gem_get_rx_desc(s, q);
963     }
964 
965     /* Count it */
966     gem_receive_updatestats(s, buf, size);
967 
968     s->regs[GEM_RXSTATUS] |= GEM_RXSTATUS_FRMRCVD;
969     s->regs[GEM_ISR] |= GEM_INT_RXCMPL & ~(s->regs[GEM_IMR]);
970 
971     /* Handle interrupt consequences */
972     gem_update_int_status(s);
973 
974     return size;
975 }
976 
977 /*
978  * gem_transmit_updatestats:
979  * Increment transmit statistics.
980  */
981 static void gem_transmit_updatestats(CadenceGEMState *s, const uint8_t *packet,
982                                      unsigned bytes)
983 {
984     uint64_t octets;
985 
986     /* Total octets (bytes) transmitted */
987     octets = ((uint64_t)(s->regs[GEM_OCTTXLO]) << 32) |
988              s->regs[GEM_OCTTXHI];
989     octets += bytes;
990     s->regs[GEM_OCTTXLO] = octets >> 32;
991     s->regs[GEM_OCTTXHI] = octets;
992 
993     /* Error-free Frames transmitted */
994     s->regs[GEM_TXCNT]++;
995 
996     /* Error-free Broadcast Frames counter */
997     if (!memcmp(packet, broadcast_addr, 6)) {
998         s->regs[GEM_TXBCNT]++;
999     }
1000 
1001     /* Error-free Multicast Frames counter */
1002     if (packet[0] == 0x01) {
1003         s->regs[GEM_TXMCNT]++;
1004     }
1005 
1006     if (bytes <= 64) {
1007         s->regs[GEM_TX64CNT]++;
1008     } else if (bytes <= 127) {
1009         s->regs[GEM_TX65CNT]++;
1010     } else if (bytes <= 255) {
1011         s->regs[GEM_TX128CNT]++;
1012     } else if (bytes <= 511) {
1013         s->regs[GEM_TX256CNT]++;
1014     } else if (bytes <= 1023) {
1015         s->regs[GEM_TX512CNT]++;
1016     } else if (bytes <= 1518) {
1017         s->regs[GEM_TX1024CNT]++;
1018     } else {
1019         s->regs[GEM_TX1519CNT]++;
1020     }
1021 }
1022 
1023 /*
1024  * gem_transmit:
1025  * Fish packets out of the descriptor ring and feed them to QEMU
1026  */
1027 static void gem_transmit(CadenceGEMState *s)
1028 {
1029     unsigned    desc[2];
1030     hwaddr packet_desc_addr;
1031     uint8_t     tx_packet[2048];
1032     uint8_t     *p;
1033     unsigned    total_bytes;
1034     int q = 0;
1035 
1036     /* Do nothing if transmit is not enabled. */
1037     if (!(s->regs[GEM_NWCTRL] & GEM_NWCTRL_TXENA)) {
1038         return;
1039     }
1040 
1041     DB_PRINT("\n");
1042 
1043     /* The packet we will hand off to QEMU.
1044      * Packets scattered across multiple descriptors are gathered to this
1045      * one contiguous buffer first.
1046      */
1047     p = tx_packet;
1048     total_bytes = 0;
1049 
1050     for (q = s->num_priority_queues - 1; q >= 0; q--) {
1051         /* read current descriptor */
1052         packet_desc_addr = s->tx_desc_addr[q];
1053 
1054         DB_PRINT("read descriptor 0x%" HWADDR_PRIx "\n", packet_desc_addr);
1055         cpu_physical_memory_read(packet_desc_addr,
1056                                  (uint8_t *)desc, sizeof(desc));
1057         /* Handle all descriptors owned by hardware */
1058         while (tx_desc_get_used(desc) == 0) {
1059 
1060             /* Do nothing if transmit is not enabled. */
1061             if (!(s->regs[GEM_NWCTRL] & GEM_NWCTRL_TXENA)) {
1062                 return;
1063             }
1064             print_gem_tx_desc(desc, q);
1065 
1066             /* The real hardware would eat this (and possibly crash).
1067              * For QEMU let's lend a helping hand.
1068              */
1069             if ((tx_desc_get_buffer(desc) == 0) ||
1070                 (tx_desc_get_length(desc) == 0)) {
1071                 DB_PRINT("Invalid TX descriptor @ 0x%x\n",
1072                          (unsigned)packet_desc_addr);
1073                 break;
1074             }
1075 
1076             if (tx_desc_get_length(desc) > sizeof(tx_packet) -
1077                                                (p - tx_packet)) {
1078                 DB_PRINT("TX descriptor @ 0x%x too large: size 0x%x space " \
1079                          "0x%x\n", (unsigned)packet_desc_addr,
1080                          (unsigned)tx_desc_get_length(desc),
1081                          sizeof(tx_packet) - (p - tx_packet));
1082                 break;
1083             }
1084 
1085             /* Gather this fragment of the packet from "dma memory" to our
1086              * contig buffer.
1087              */
1088             cpu_physical_memory_read(tx_desc_get_buffer(desc), p,
1089                                      tx_desc_get_length(desc));
1090             p += tx_desc_get_length(desc);
1091             total_bytes += tx_desc_get_length(desc);
1092 
1093             /* Last descriptor for this packet; hand the whole thing off */
1094             if (tx_desc_get_last(desc)) {
1095                 unsigned    desc_first[2];
1096 
1097                 /* Modify the 1st descriptor of this packet to be owned by
1098                  * the processor.
1099                  */
1100                 cpu_physical_memory_read(s->tx_desc_addr[q],
1101                                          (uint8_t *)desc_first,
1102                                          sizeof(desc_first));
1103                 tx_desc_set_used(desc_first);
1104                 cpu_physical_memory_write(s->tx_desc_addr[q],
1105                                           (uint8_t *)desc_first,
1106                                           sizeof(desc_first));
1107                 /* Advance the hardware current descriptor past this packet */
1108                 if (tx_desc_get_wrap(desc)) {
1109                     s->tx_desc_addr[q] = s->regs[GEM_TXQBASE];
1110                 } else {
1111                     s->tx_desc_addr[q] = packet_desc_addr + 8;
1112                 }
1113                 DB_PRINT("TX descriptor next: 0x%08x\n", s->tx_desc_addr[q]);
1114 
1115                 s->regs[GEM_TXSTATUS] |= GEM_TXSTATUS_TXCMPL;
1116                 s->regs[GEM_ISR] |= GEM_INT_TXCMPL & ~(s->regs[GEM_IMR]);
1117 
1118                 /* Update queue interrupt status */
1119                 if (s->num_priority_queues > 1) {
1120                     s->regs[GEM_INT_Q1_STATUS + q] |=
1121                             GEM_INT_TXCMPL & ~(s->regs[GEM_INT_Q1_MASK + q]);
1122                 }
1123 
1124                 /* Handle interrupt consequences */
1125                 gem_update_int_status(s);
1126 
1127                 /* Is checksum offload enabled? */
1128                 if (s->regs[GEM_DMACFG] & GEM_DMACFG_TXCSUM_OFFL) {
1129                     net_checksum_calculate(tx_packet, total_bytes);
1130                 }
1131 
1132                 /* Update MAC statistics */
1133                 gem_transmit_updatestats(s, tx_packet, total_bytes);
1134 
1135                 /* Send the packet somewhere */
1136                 if (s->phy_loop || (s->regs[GEM_NWCTRL] &
1137                                     GEM_NWCTRL_LOCALLOOP)) {
1138                     gem_receive(qemu_get_queue(s->nic), tx_packet,
1139                                 total_bytes);
1140                 } else {
1141                     qemu_send_packet(qemu_get_queue(s->nic), tx_packet,
1142                                      total_bytes);
1143                 }
1144 
1145                 /* Prepare for next packet */
1146                 p = tx_packet;
1147                 total_bytes = 0;
1148             }
1149 
1150             /* read next descriptor */
1151             if (tx_desc_get_wrap(desc)) {
1152                 tx_desc_set_last(desc);
1153                 packet_desc_addr = s->regs[GEM_TXQBASE];
1154             } else {
1155                 packet_desc_addr += 8;
1156             }
1157             DB_PRINT("read descriptor 0x%" HWADDR_PRIx "\n", packet_desc_addr);
1158             cpu_physical_memory_read(packet_desc_addr,
1159                                      (uint8_t *)desc, sizeof(desc));
1160         }
1161 
1162         if (tx_desc_get_used(desc)) {
1163             s->regs[GEM_TXSTATUS] |= GEM_TXSTATUS_USED;
1164             s->regs[GEM_ISR] |= GEM_INT_TXUSED & ~(s->regs[GEM_IMR]);
1165             gem_update_int_status(s);
1166         }
1167     }
1168 }
1169 
1170 static void gem_phy_reset(CadenceGEMState *s)
1171 {
1172     memset(&s->phy_regs[0], 0, sizeof(s->phy_regs));
1173     s->phy_regs[PHY_REG_CONTROL] = 0x1140;
1174     s->phy_regs[PHY_REG_STATUS] = 0x7969;
1175     s->phy_regs[PHY_REG_PHYID1] = 0x0141;
1176     s->phy_regs[PHY_REG_PHYID2] = 0x0CC2;
1177     s->phy_regs[PHY_REG_ANEGADV] = 0x01E1;
1178     s->phy_regs[PHY_REG_LINKPABIL] = 0xCDE1;
1179     s->phy_regs[PHY_REG_ANEGEXP] = 0x000F;
1180     s->phy_regs[PHY_REG_NEXTP] = 0x2001;
1181     s->phy_regs[PHY_REG_LINKPNEXTP] = 0x40E6;
1182     s->phy_regs[PHY_REG_100BTCTRL] = 0x0300;
1183     s->phy_regs[PHY_REG_1000BTSTAT] = 0x7C00;
1184     s->phy_regs[PHY_REG_EXTSTAT] = 0x3000;
1185     s->phy_regs[PHY_REG_PHYSPCFC_CTL] = 0x0078;
1186     s->phy_regs[PHY_REG_PHYSPCFC_ST] = 0x7C00;
1187     s->phy_regs[PHY_REG_EXT_PHYSPCFC_CTL] = 0x0C60;
1188     s->phy_regs[PHY_REG_LED] = 0x4100;
1189     s->phy_regs[PHY_REG_EXT_PHYSPCFC_CTL2] = 0x000A;
1190     s->phy_regs[PHY_REG_EXT_PHYSPCFC_ST] = 0x848B;
1191 
1192     phy_update_link(s);
1193 }
1194 
1195 static void gem_reset(DeviceState *d)
1196 {
1197     int i;
1198     CadenceGEMState *s = CADENCE_GEM(d);
1199     const uint8_t *a;
1200 
1201     DB_PRINT("\n");
1202 
1203     /* Set post reset register values */
1204     memset(&s->regs[0], 0, sizeof(s->regs));
1205     s->regs[GEM_NWCFG] = 0x00080000;
1206     s->regs[GEM_NWSTATUS] = 0x00000006;
1207     s->regs[GEM_DMACFG] = 0x00020784;
1208     s->regs[GEM_IMR] = 0x07ffffff;
1209     s->regs[GEM_TXPAUSE] = 0x0000ffff;
1210     s->regs[GEM_TXPARTIALSF] = 0x000003ff;
1211     s->regs[GEM_RXPARTIALSF] = 0x000003ff;
1212     s->regs[GEM_MODID] = 0x00020118;
1213     s->regs[GEM_DESCONF] = 0x02500111;
1214     s->regs[GEM_DESCONF2] = 0x2ab13fff;
1215     s->regs[GEM_DESCONF5] = 0x002f2145;
1216     s->regs[GEM_DESCONF6] = 0x00000200;
1217 
1218     /* Set MAC address */
1219     a = &s->conf.macaddr.a[0];
1220     s->regs[GEM_SPADDR1LO] = a[0] | (a[1] << 8) | (a[2] << 16) | (a[3] << 24);
1221     s->regs[GEM_SPADDR1HI] = a[4] | (a[5] << 8);
1222 
1223     for (i = 0; i < 4; i++) {
1224         s->sar_active[i] = false;
1225     }
1226 
1227     gem_phy_reset(s);
1228 
1229     gem_update_int_status(s);
1230 }
1231 
1232 static uint16_t gem_phy_read(CadenceGEMState *s, unsigned reg_num)
1233 {
1234     DB_PRINT("reg: %d value: 0x%04x\n", reg_num, s->phy_regs[reg_num]);
1235     return s->phy_regs[reg_num];
1236 }
1237 
1238 static void gem_phy_write(CadenceGEMState *s, unsigned reg_num, uint16_t val)
1239 {
1240     DB_PRINT("reg: %d value: 0x%04x\n", reg_num, val);
1241 
1242     switch (reg_num) {
1243     case PHY_REG_CONTROL:
1244         if (val & PHY_REG_CONTROL_RST) {
1245             /* Phy reset */
1246             gem_phy_reset(s);
1247             val &= ~(PHY_REG_CONTROL_RST | PHY_REG_CONTROL_LOOP);
1248             s->phy_loop = 0;
1249         }
1250         if (val & PHY_REG_CONTROL_ANEG) {
1251             /* Complete autonegotiation immediately */
1252             val &= ~PHY_REG_CONTROL_ANEG;
1253             s->phy_regs[PHY_REG_STATUS] |= PHY_REG_STATUS_ANEGCMPL;
1254         }
1255         if (val & PHY_REG_CONTROL_LOOP) {
1256             DB_PRINT("PHY placed in loopback\n");
1257             s->phy_loop = 1;
1258         } else {
1259             s->phy_loop = 0;
1260         }
1261         break;
1262     }
1263     s->phy_regs[reg_num] = val;
1264 }
1265 
1266 /*
1267  * gem_read32:
1268  * Read a GEM register.
1269  */
1270 static uint64_t gem_read(void *opaque, hwaddr offset, unsigned size)
1271 {
1272     CadenceGEMState *s;
1273     uint32_t retval;
1274     int i;
1275     s = (CadenceGEMState *)opaque;
1276 
1277     offset >>= 2;
1278     retval = s->regs[offset];
1279 
1280     DB_PRINT("offset: 0x%04x read: 0x%08x\n", (unsigned)offset*4, retval);
1281 
1282     switch (offset) {
1283     case GEM_ISR:
1284         DB_PRINT("lowering irqs on ISR read\n");
1285         for (i = 0; i < s->num_priority_queues; ++i) {
1286             qemu_set_irq(s->irq[i], 0);
1287         }
1288         break;
1289     case GEM_PHYMNTNC:
1290         if (retval & GEM_PHYMNTNC_OP_R) {
1291             uint32_t phy_addr, reg_num;
1292 
1293             phy_addr = (retval & GEM_PHYMNTNC_ADDR) >> GEM_PHYMNTNC_ADDR_SHFT;
1294             if (phy_addr == BOARD_PHY_ADDRESS || phy_addr == 0) {
1295                 reg_num = (retval & GEM_PHYMNTNC_REG) >> GEM_PHYMNTNC_REG_SHIFT;
1296                 retval &= 0xFFFF0000;
1297                 retval |= gem_phy_read(s, reg_num);
1298             } else {
1299                 retval |= 0xFFFF; /* No device at this address */
1300             }
1301         }
1302         break;
1303     }
1304 
1305     /* Squash read to clear bits */
1306     s->regs[offset] &= ~(s->regs_rtc[offset]);
1307 
1308     /* Do not provide write only bits */
1309     retval &= ~(s->regs_wo[offset]);
1310 
1311     DB_PRINT("0x%08x\n", retval);
1312     gem_update_int_status(s);
1313     return retval;
1314 }
1315 
1316 /*
1317  * gem_write32:
1318  * Write a GEM register.
1319  */
1320 static void gem_write(void *opaque, hwaddr offset, uint64_t val,
1321         unsigned size)
1322 {
1323     CadenceGEMState *s = (CadenceGEMState *)opaque;
1324     uint32_t readonly;
1325     int i;
1326 
1327     DB_PRINT("offset: 0x%04x write: 0x%08x ", (unsigned)offset, (unsigned)val);
1328     offset >>= 2;
1329 
1330     /* Squash bits which are read only in write value */
1331     val &= ~(s->regs_ro[offset]);
1332     /* Preserve (only) bits which are read only and wtc in register */
1333     readonly = s->regs[offset] & (s->regs_ro[offset] | s->regs_w1c[offset]);
1334 
1335     /* Copy register write to backing store */
1336     s->regs[offset] = (val & ~s->regs_w1c[offset]) | readonly;
1337 
1338     /* do w1c */
1339     s->regs[offset] &= ~(s->regs_w1c[offset] & val);
1340 
1341     /* Handle register write side effects */
1342     switch (offset) {
1343     case GEM_NWCTRL:
1344         if (val & GEM_NWCTRL_RXENA) {
1345             for (i = 0; i < s->num_priority_queues; ++i) {
1346                 gem_get_rx_desc(s, i);
1347             }
1348         }
1349         if (val & GEM_NWCTRL_TXSTART) {
1350             gem_transmit(s);
1351         }
1352         if (!(val & GEM_NWCTRL_TXENA)) {
1353             /* Reset to start of Q when transmit disabled. */
1354             for (i = 0; i < s->num_priority_queues; i++) {
1355                 s->tx_desc_addr[i] = s->regs[GEM_TXQBASE];
1356             }
1357         }
1358         if (gem_can_receive(qemu_get_queue(s->nic))) {
1359             qemu_flush_queued_packets(qemu_get_queue(s->nic));
1360         }
1361         break;
1362 
1363     case GEM_TXSTATUS:
1364         gem_update_int_status(s);
1365         break;
1366     case GEM_RXQBASE:
1367         s->rx_desc_addr[0] = val;
1368         break;
1369     case GEM_RECEIVE_Q1_PTR ... GEM_RECEIVE_Q7_PTR:
1370         s->rx_desc_addr[offset - GEM_RECEIVE_Q1_PTR + 1] = val;
1371         break;
1372     case GEM_TXQBASE:
1373         s->tx_desc_addr[0] = val;
1374         break;
1375     case GEM_TRANSMIT_Q1_PTR ... GEM_TRANSMIT_Q7_PTR:
1376         s->tx_desc_addr[offset - GEM_TRANSMIT_Q1_PTR + 1] = val;
1377         break;
1378     case GEM_RXSTATUS:
1379         gem_update_int_status(s);
1380         break;
1381     case GEM_IER:
1382         s->regs[GEM_IMR] &= ~val;
1383         gem_update_int_status(s);
1384         break;
1385     case GEM_INT_Q1_ENABLE ... GEM_INT_Q7_ENABLE:
1386         s->regs[GEM_INT_Q1_MASK + offset - GEM_INT_Q1_ENABLE] &= ~val;
1387         gem_update_int_status(s);
1388         break;
1389     case GEM_IDR:
1390         s->regs[GEM_IMR] |= val;
1391         gem_update_int_status(s);
1392         break;
1393     case GEM_INT_Q1_DISABLE ... GEM_INT_Q7_DISABLE:
1394         s->regs[GEM_INT_Q1_MASK + offset - GEM_INT_Q1_DISABLE] |= val;
1395         gem_update_int_status(s);
1396         break;
1397     case GEM_SPADDR1LO:
1398     case GEM_SPADDR2LO:
1399     case GEM_SPADDR3LO:
1400     case GEM_SPADDR4LO:
1401         s->sar_active[(offset - GEM_SPADDR1LO) / 2] = false;
1402         break;
1403     case GEM_SPADDR1HI:
1404     case GEM_SPADDR2HI:
1405     case GEM_SPADDR3HI:
1406     case GEM_SPADDR4HI:
1407         s->sar_active[(offset - GEM_SPADDR1HI) / 2] = true;
1408         break;
1409     case GEM_PHYMNTNC:
1410         if (val & GEM_PHYMNTNC_OP_W) {
1411             uint32_t phy_addr, reg_num;
1412 
1413             phy_addr = (val & GEM_PHYMNTNC_ADDR) >> GEM_PHYMNTNC_ADDR_SHFT;
1414             if (phy_addr == BOARD_PHY_ADDRESS || phy_addr == 0) {
1415                 reg_num = (val & GEM_PHYMNTNC_REG) >> GEM_PHYMNTNC_REG_SHIFT;
1416                 gem_phy_write(s, reg_num, val);
1417             }
1418         }
1419         break;
1420     }
1421 
1422     DB_PRINT("newval: 0x%08x\n", s->regs[offset]);
1423 }
1424 
1425 static const MemoryRegionOps gem_ops = {
1426     .read = gem_read,
1427     .write = gem_write,
1428     .endianness = DEVICE_LITTLE_ENDIAN,
1429 };
1430 
1431 static void gem_set_link(NetClientState *nc)
1432 {
1433     CadenceGEMState *s = qemu_get_nic_opaque(nc);
1434 
1435     DB_PRINT("\n");
1436     phy_update_link(s);
1437     gem_update_int_status(s);
1438 }
1439 
1440 static NetClientInfo net_gem_info = {
1441     .type = NET_CLIENT_DRIVER_NIC,
1442     .size = sizeof(NICState),
1443     .can_receive = gem_can_receive,
1444     .receive = gem_receive,
1445     .link_status_changed = gem_set_link,
1446 };
1447 
1448 static void gem_realize(DeviceState *dev, Error **errp)
1449 {
1450     CadenceGEMState *s = CADENCE_GEM(dev);
1451     int i;
1452 
1453     if (s->num_priority_queues == 0 ||
1454         s->num_priority_queues > MAX_PRIORITY_QUEUES) {
1455         error_setg(errp, "Invalid num-priority-queues value: %" PRIx8,
1456                    s->num_priority_queues);
1457         return;
1458     } else if (s->num_type1_screeners > MAX_TYPE1_SCREENERS) {
1459         error_setg(errp, "Invalid num-type1-screeners value: %" PRIx8,
1460                    s->num_type1_screeners);
1461         return;
1462     } else if (s->num_type2_screeners > MAX_TYPE2_SCREENERS) {
1463         error_setg(errp, "Invalid num-type2-screeners value: %" PRIx8,
1464                    s->num_type2_screeners);
1465         return;
1466     }
1467 
1468     for (i = 0; i < s->num_priority_queues; ++i) {
1469         sysbus_init_irq(SYS_BUS_DEVICE(dev), &s->irq[i]);
1470     }
1471 
1472     qemu_macaddr_default_if_unset(&s->conf.macaddr);
1473 
1474     s->nic = qemu_new_nic(&net_gem_info, &s->conf,
1475                           object_get_typename(OBJECT(dev)), dev->id, s);
1476 }
1477 
1478 static void gem_init(Object *obj)
1479 {
1480     CadenceGEMState *s = CADENCE_GEM(obj);
1481     DeviceState *dev = DEVICE(obj);
1482 
1483     DB_PRINT("\n");
1484 
1485     gem_init_register_masks(s);
1486     memory_region_init_io(&s->iomem, OBJECT(s), &gem_ops, s,
1487                           "enet", sizeof(s->regs));
1488 
1489     sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->iomem);
1490 }
1491 
1492 static const VMStateDescription vmstate_cadence_gem = {
1493     .name = "cadence_gem",
1494     .version_id = 4,
1495     .minimum_version_id = 4,
1496     .fields = (VMStateField[]) {
1497         VMSTATE_UINT32_ARRAY(regs, CadenceGEMState, CADENCE_GEM_MAXREG),
1498         VMSTATE_UINT16_ARRAY(phy_regs, CadenceGEMState, 32),
1499         VMSTATE_UINT8(phy_loop, CadenceGEMState),
1500         VMSTATE_UINT32_ARRAY(rx_desc_addr, CadenceGEMState,
1501                              MAX_PRIORITY_QUEUES),
1502         VMSTATE_UINT32_ARRAY(tx_desc_addr, CadenceGEMState,
1503                              MAX_PRIORITY_QUEUES),
1504         VMSTATE_BOOL_ARRAY(sar_active, CadenceGEMState, 4),
1505         VMSTATE_END_OF_LIST(),
1506     }
1507 };
1508 
1509 static Property gem_properties[] = {
1510     DEFINE_NIC_PROPERTIES(CadenceGEMState, conf),
1511     DEFINE_PROP_UINT8("num-priority-queues", CadenceGEMState,
1512                       num_priority_queues, 1),
1513     DEFINE_PROP_UINT8("num-type1-screeners", CadenceGEMState,
1514                       num_type1_screeners, 4),
1515     DEFINE_PROP_UINT8("num-type2-screeners", CadenceGEMState,
1516                       num_type2_screeners, 4),
1517     DEFINE_PROP_END_OF_LIST(),
1518 };
1519 
1520 static void gem_class_init(ObjectClass *klass, void *data)
1521 {
1522     DeviceClass *dc = DEVICE_CLASS(klass);
1523 
1524     dc->realize = gem_realize;
1525     dc->props = gem_properties;
1526     dc->vmsd = &vmstate_cadence_gem;
1527     dc->reset = gem_reset;
1528 }
1529 
1530 static const TypeInfo gem_info = {
1531     .name  = TYPE_CADENCE_GEM,
1532     .parent = TYPE_SYS_BUS_DEVICE,
1533     .instance_size  = sizeof(CadenceGEMState),
1534     .instance_init = gem_init,
1535     .class_init = gem_class_init,
1536 };
1537 
1538 static void gem_register_types(void)
1539 {
1540     type_register_static(&gem_info);
1541 }
1542 
1543 type_init(gem_register_types)
1544