xref: /openbmc/qemu/hw/net/can/xlnx-zynqmp-can.c (revision 7c08eefc)
1 /*
2  * QEMU model of the Xilinx ZynqMP CAN controller.
3  * This implementation is based on the following datasheet:
4  * https://www.xilinx.com/support/documentation/user_guides/ug1085-zynq-ultrascale-trm.pdf
5  *
6  * Copyright (c) 2020 Xilinx Inc.
7  *
8  * Written-by: Vikram Garhwal<fnu.vikram@xilinx.com>
9  *
10  * Based on QEMU CAN Device emulation implemented by Jin Yang, Deniz Eren and
11  * Pavel Pisa
12  *
13  * Permission is hereby granted, free of charge, to any person obtaining a copy
14  * of this software and associated documentation files (the "Software"), to deal
15  * in the Software without restriction, including without limitation the rights
16  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
17  * copies of the Software, and to permit persons to whom the Software is
18  * furnished to do so, subject to the following conditions:
19  *
20  * The above copyright notice and this permission notice shall be included in
21  * all copies or substantial portions of the Software.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
24  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
25  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
26  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
27  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
28  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
29  * THE SOFTWARE.
30  */
31 
32 #include "qemu/osdep.h"
33 #include "hw/sysbus.h"
34 #include "hw/register.h"
35 #include "hw/irq.h"
36 #include "qapi/error.h"
37 #include "qemu/bitops.h"
38 #include "qemu/log.h"
39 #include "qemu/cutils.h"
40 #include "migration/vmstate.h"
41 #include "hw/qdev-properties.h"
42 #include "net/can_emu.h"
43 #include "net/can_host.h"
44 #include "qemu/event_notifier.h"
45 #include "qom/object_interfaces.h"
46 #include "hw/net/xlnx-zynqmp-can.h"
47 #include "trace.h"
48 
49 #ifndef XLNX_ZYNQMP_CAN_ERR_DEBUG
50 #define XLNX_ZYNQMP_CAN_ERR_DEBUG 0
51 #endif
52 
53 #define MAX_DLC            8
54 #undef ERROR
55 
56 REG32(SOFTWARE_RESET_REGISTER, 0x0)
57     FIELD(SOFTWARE_RESET_REGISTER, CEN, 1, 1)
58     FIELD(SOFTWARE_RESET_REGISTER, SRST, 0, 1)
59 REG32(MODE_SELECT_REGISTER, 0x4)
60     FIELD(MODE_SELECT_REGISTER, SNOOP, 2, 1)
61     FIELD(MODE_SELECT_REGISTER, LBACK, 1, 1)
62     FIELD(MODE_SELECT_REGISTER, SLEEP, 0, 1)
63 REG32(ARBITRATION_PHASE_BAUD_RATE_PRESCALER_REGISTER, 0x8)
64     FIELD(ARBITRATION_PHASE_BAUD_RATE_PRESCALER_REGISTER, BRP, 0, 8)
65 REG32(ARBITRATION_PHASE_BIT_TIMING_REGISTER, 0xc)
66     FIELD(ARBITRATION_PHASE_BIT_TIMING_REGISTER, SJW, 7, 2)
67     FIELD(ARBITRATION_PHASE_BIT_TIMING_REGISTER, TS2, 4, 3)
68     FIELD(ARBITRATION_PHASE_BIT_TIMING_REGISTER, TS1, 0, 4)
69 REG32(ERROR_COUNTER_REGISTER, 0x10)
70     FIELD(ERROR_COUNTER_REGISTER, REC, 8, 8)
71     FIELD(ERROR_COUNTER_REGISTER, TEC, 0, 8)
72 REG32(ERROR_STATUS_REGISTER, 0x14)
73     FIELD(ERROR_STATUS_REGISTER, ACKER, 4, 1)
74     FIELD(ERROR_STATUS_REGISTER, BERR, 3, 1)
75     FIELD(ERROR_STATUS_REGISTER, STER, 2, 1)
76     FIELD(ERROR_STATUS_REGISTER, FMER, 1, 1)
77     FIELD(ERROR_STATUS_REGISTER, CRCER, 0, 1)
78 REG32(STATUS_REGISTER, 0x18)
79     FIELD(STATUS_REGISTER, SNOOP, 12, 1)
80     FIELD(STATUS_REGISTER, ACFBSY, 11, 1)
81     FIELD(STATUS_REGISTER, TXFLL, 10, 1)
82     FIELD(STATUS_REGISTER, TXBFLL, 9, 1)
83     FIELD(STATUS_REGISTER, ESTAT, 7, 2)
84     FIELD(STATUS_REGISTER, ERRWRN, 6, 1)
85     FIELD(STATUS_REGISTER, BBSY, 5, 1)
86     FIELD(STATUS_REGISTER, BIDLE, 4, 1)
87     FIELD(STATUS_REGISTER, NORMAL, 3, 1)
88     FIELD(STATUS_REGISTER, SLEEP, 2, 1)
89     FIELD(STATUS_REGISTER, LBACK, 1, 1)
90     FIELD(STATUS_REGISTER, CONFIG, 0, 1)
91 REG32(INTERRUPT_STATUS_REGISTER, 0x1c)
92     FIELD(INTERRUPT_STATUS_REGISTER, TXFEMP, 14, 1)
93     FIELD(INTERRUPT_STATUS_REGISTER, TXFWMEMP, 13, 1)
94     FIELD(INTERRUPT_STATUS_REGISTER, RXFWMFLL, 12, 1)
95     FIELD(INTERRUPT_STATUS_REGISTER, WKUP, 11, 1)
96     FIELD(INTERRUPT_STATUS_REGISTER, SLP, 10, 1)
97     FIELD(INTERRUPT_STATUS_REGISTER, BSOFF, 9, 1)
98     FIELD(INTERRUPT_STATUS_REGISTER, ERROR, 8, 1)
99     FIELD(INTERRUPT_STATUS_REGISTER, RXNEMP, 7, 1)
100     FIELD(INTERRUPT_STATUS_REGISTER, RXOFLW, 6, 1)
101     FIELD(INTERRUPT_STATUS_REGISTER, RXUFLW, 5, 1)
102     FIELD(INTERRUPT_STATUS_REGISTER, RXOK, 4, 1)
103     FIELD(INTERRUPT_STATUS_REGISTER, TXBFLL, 3, 1)
104     FIELD(INTERRUPT_STATUS_REGISTER, TXFLL, 2, 1)
105     FIELD(INTERRUPT_STATUS_REGISTER, TXOK, 1, 1)
106     FIELD(INTERRUPT_STATUS_REGISTER, ARBLST, 0, 1)
107 REG32(INTERRUPT_ENABLE_REGISTER, 0x20)
108     FIELD(INTERRUPT_ENABLE_REGISTER, ETXFEMP, 14, 1)
109     FIELD(INTERRUPT_ENABLE_REGISTER, ETXFWMEMP, 13, 1)
110     FIELD(INTERRUPT_ENABLE_REGISTER, ERXFWMFLL, 12, 1)
111     FIELD(INTERRUPT_ENABLE_REGISTER, EWKUP, 11, 1)
112     FIELD(INTERRUPT_ENABLE_REGISTER, ESLP, 10, 1)
113     FIELD(INTERRUPT_ENABLE_REGISTER, EBSOFF, 9, 1)
114     FIELD(INTERRUPT_ENABLE_REGISTER, EERROR, 8, 1)
115     FIELD(INTERRUPT_ENABLE_REGISTER, ERXNEMP, 7, 1)
116     FIELD(INTERRUPT_ENABLE_REGISTER, ERXOFLW, 6, 1)
117     FIELD(INTERRUPT_ENABLE_REGISTER, ERXUFLW, 5, 1)
118     FIELD(INTERRUPT_ENABLE_REGISTER, ERXOK, 4, 1)
119     FIELD(INTERRUPT_ENABLE_REGISTER, ETXBFLL, 3, 1)
120     FIELD(INTERRUPT_ENABLE_REGISTER, ETXFLL, 2, 1)
121     FIELD(INTERRUPT_ENABLE_REGISTER, ETXOK, 1, 1)
122     FIELD(INTERRUPT_ENABLE_REGISTER, EARBLST, 0, 1)
123 REG32(INTERRUPT_CLEAR_REGISTER, 0x24)
124     FIELD(INTERRUPT_CLEAR_REGISTER, CTXFEMP, 14, 1)
125     FIELD(INTERRUPT_CLEAR_REGISTER, CTXFWMEMP, 13, 1)
126     FIELD(INTERRUPT_CLEAR_REGISTER, CRXFWMFLL, 12, 1)
127     FIELD(INTERRUPT_CLEAR_REGISTER, CWKUP, 11, 1)
128     FIELD(INTERRUPT_CLEAR_REGISTER, CSLP, 10, 1)
129     FIELD(INTERRUPT_CLEAR_REGISTER, CBSOFF, 9, 1)
130     FIELD(INTERRUPT_CLEAR_REGISTER, CERROR, 8, 1)
131     FIELD(INTERRUPT_CLEAR_REGISTER, CRXNEMP, 7, 1)
132     FIELD(INTERRUPT_CLEAR_REGISTER, CRXOFLW, 6, 1)
133     FIELD(INTERRUPT_CLEAR_REGISTER, CRXUFLW, 5, 1)
134     FIELD(INTERRUPT_CLEAR_REGISTER, CRXOK, 4, 1)
135     FIELD(INTERRUPT_CLEAR_REGISTER, CTXBFLL, 3, 1)
136     FIELD(INTERRUPT_CLEAR_REGISTER, CTXFLL, 2, 1)
137     FIELD(INTERRUPT_CLEAR_REGISTER, CTXOK, 1, 1)
138     FIELD(INTERRUPT_CLEAR_REGISTER, CARBLST, 0, 1)
139 REG32(TIMESTAMP_REGISTER, 0x28)
140     FIELD(TIMESTAMP_REGISTER, CTS, 0, 1)
141 REG32(WIR, 0x2c)
142     FIELD(WIR, EW, 8, 8)
143     FIELD(WIR, FW, 0, 8)
144 REG32(TXFIFO_ID, 0x30)
145     FIELD(TXFIFO_ID, IDH, 21, 11)
146     FIELD(TXFIFO_ID, SRRRTR, 20, 1)
147     FIELD(TXFIFO_ID, IDE, 19, 1)
148     FIELD(TXFIFO_ID, IDL, 1, 18)
149     FIELD(TXFIFO_ID, RTR, 0, 1)
150 REG32(TXFIFO_DLC, 0x34)
151     FIELD(TXFIFO_DLC, DLC, 28, 4)
152 REG32(TXFIFO_DATA1, 0x38)
153     FIELD(TXFIFO_DATA1, DB0, 24, 8)
154     FIELD(TXFIFO_DATA1, DB1, 16, 8)
155     FIELD(TXFIFO_DATA1, DB2, 8, 8)
156     FIELD(TXFIFO_DATA1, DB3, 0, 8)
157 REG32(TXFIFO_DATA2, 0x3c)
158     FIELD(TXFIFO_DATA2, DB4, 24, 8)
159     FIELD(TXFIFO_DATA2, DB5, 16, 8)
160     FIELD(TXFIFO_DATA2, DB6, 8, 8)
161     FIELD(TXFIFO_DATA2, DB7, 0, 8)
162 REG32(TXHPB_ID, 0x40)
163     FIELD(TXHPB_ID, IDH, 21, 11)
164     FIELD(TXHPB_ID, SRRRTR, 20, 1)
165     FIELD(TXHPB_ID, IDE, 19, 1)
166     FIELD(TXHPB_ID, IDL, 1, 18)
167     FIELD(TXHPB_ID, RTR, 0, 1)
168 REG32(TXHPB_DLC, 0x44)
169     FIELD(TXHPB_DLC, DLC, 28, 4)
170 REG32(TXHPB_DATA1, 0x48)
171     FIELD(TXHPB_DATA1, DB0, 24, 8)
172     FIELD(TXHPB_DATA1, DB1, 16, 8)
173     FIELD(TXHPB_DATA1, DB2, 8, 8)
174     FIELD(TXHPB_DATA1, DB3, 0, 8)
175 REG32(TXHPB_DATA2, 0x4c)
176     FIELD(TXHPB_DATA2, DB4, 24, 8)
177     FIELD(TXHPB_DATA2, DB5, 16, 8)
178     FIELD(TXHPB_DATA2, DB6, 8, 8)
179     FIELD(TXHPB_DATA2, DB7, 0, 8)
180 REG32(RXFIFO_ID, 0x50)
181     FIELD(RXFIFO_ID, IDH, 21, 11)
182     FIELD(RXFIFO_ID, SRRRTR, 20, 1)
183     FIELD(RXFIFO_ID, IDE, 19, 1)
184     FIELD(RXFIFO_ID, IDL, 1, 18)
185     FIELD(RXFIFO_ID, RTR, 0, 1)
186 REG32(RXFIFO_DLC, 0x54)
187     FIELD(RXFIFO_DLC, DLC, 28, 4)
188     FIELD(RXFIFO_DLC, RXT, 0, 16)
189 REG32(RXFIFO_DATA1, 0x58)
190     FIELD(RXFIFO_DATA1, DB0, 24, 8)
191     FIELD(RXFIFO_DATA1, DB1, 16, 8)
192     FIELD(RXFIFO_DATA1, DB2, 8, 8)
193     FIELD(RXFIFO_DATA1, DB3, 0, 8)
194 REG32(RXFIFO_DATA2, 0x5c)
195     FIELD(RXFIFO_DATA2, DB4, 24, 8)
196     FIELD(RXFIFO_DATA2, DB5, 16, 8)
197     FIELD(RXFIFO_DATA2, DB6, 8, 8)
198     FIELD(RXFIFO_DATA2, DB7, 0, 8)
199 REG32(AFR, 0x60)
200     FIELD(AFR, UAF4, 3, 1)
201     FIELD(AFR, UAF3, 2, 1)
202     FIELD(AFR, UAF2, 1, 1)
203     FIELD(AFR, UAF1, 0, 1)
204 REG32(AFMR1, 0x64)
205     FIELD(AFMR1, AMIDH, 21, 11)
206     FIELD(AFMR1, AMSRR, 20, 1)
207     FIELD(AFMR1, AMIDE, 19, 1)
208     FIELD(AFMR1, AMIDL, 1, 18)
209     FIELD(AFMR1, AMRTR, 0, 1)
210 REG32(AFIR1, 0x68)
211     FIELD(AFIR1, AIIDH, 21, 11)
212     FIELD(AFIR1, AISRR, 20, 1)
213     FIELD(AFIR1, AIIDE, 19, 1)
214     FIELD(AFIR1, AIIDL, 1, 18)
215     FIELD(AFIR1, AIRTR, 0, 1)
216 REG32(AFMR2, 0x6c)
217     FIELD(AFMR2, AMIDH, 21, 11)
218     FIELD(AFMR2, AMSRR, 20, 1)
219     FIELD(AFMR2, AMIDE, 19, 1)
220     FIELD(AFMR2, AMIDL, 1, 18)
221     FIELD(AFMR2, AMRTR, 0, 1)
222 REG32(AFIR2, 0x70)
223     FIELD(AFIR2, AIIDH, 21, 11)
224     FIELD(AFIR2, AISRR, 20, 1)
225     FIELD(AFIR2, AIIDE, 19, 1)
226     FIELD(AFIR2, AIIDL, 1, 18)
227     FIELD(AFIR2, AIRTR, 0, 1)
228 REG32(AFMR3, 0x74)
229     FIELD(AFMR3, AMIDH, 21, 11)
230     FIELD(AFMR3, AMSRR, 20, 1)
231     FIELD(AFMR3, AMIDE, 19, 1)
232     FIELD(AFMR3, AMIDL, 1, 18)
233     FIELD(AFMR3, AMRTR, 0, 1)
234 REG32(AFIR3, 0x78)
235     FIELD(AFIR3, AIIDH, 21, 11)
236     FIELD(AFIR3, AISRR, 20, 1)
237     FIELD(AFIR3, AIIDE, 19, 1)
238     FIELD(AFIR3, AIIDL, 1, 18)
239     FIELD(AFIR3, AIRTR, 0, 1)
240 REG32(AFMR4, 0x7c)
241     FIELD(AFMR4, AMIDH, 21, 11)
242     FIELD(AFMR4, AMSRR, 20, 1)
243     FIELD(AFMR4, AMIDE, 19, 1)
244     FIELD(AFMR4, AMIDL, 1, 18)
245     FIELD(AFMR4, AMRTR, 0, 1)
246 REG32(AFIR4, 0x80)
247     FIELD(AFIR4, AIIDH, 21, 11)
248     FIELD(AFIR4, AISRR, 20, 1)
249     FIELD(AFIR4, AIIDE, 19, 1)
250     FIELD(AFIR4, AIIDL, 1, 18)
251     FIELD(AFIR4, AIRTR, 0, 1)
252 
253 static void can_update_irq(XlnxZynqMPCANState *s)
254 {
255     uint32_t irq;
256 
257     /* Watermark register interrupts. */
258     if ((fifo32_num_free(&s->tx_fifo) / CAN_FRAME_SIZE) >
259             ARRAY_FIELD_EX32(s->regs, WIR, EW)) {
260         ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, TXFWMEMP, 1);
261     }
262 
263     if ((fifo32_num_used(&s->rx_fifo) / CAN_FRAME_SIZE) >
264             ARRAY_FIELD_EX32(s->regs, WIR, FW)) {
265         ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, RXFWMFLL, 1);
266     }
267 
268     /* RX Interrupts. */
269     if (fifo32_num_used(&s->rx_fifo) >= CAN_FRAME_SIZE) {
270         ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, RXNEMP, 1);
271     }
272 
273     /* TX interrupts. */
274     if (fifo32_is_empty(&s->tx_fifo)) {
275         ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, TXFEMP, 1);
276     }
277 
278     if (fifo32_is_full(&s->tx_fifo)) {
279         ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, TXFLL, 1);
280     }
281 
282     if (fifo32_is_full(&s->txhpb_fifo)) {
283         ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, TXBFLL, 1);
284     }
285 
286     irq = s->regs[R_INTERRUPT_STATUS_REGISTER];
287     irq &= s->regs[R_INTERRUPT_ENABLE_REGISTER];
288 
289     trace_xlnx_can_update_irq(s->regs[R_INTERRUPT_STATUS_REGISTER],
290                               s->regs[R_INTERRUPT_ENABLE_REGISTER], irq);
291     qemu_set_irq(s->irq, irq);
292 }
293 
294 static void can_ier_post_write(RegisterInfo *reg, uint64_t val)
295 {
296     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
297 
298     can_update_irq(s);
299 }
300 
301 static uint64_t can_icr_pre_write(RegisterInfo *reg, uint64_t val)
302 {
303     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
304 
305     s->regs[R_INTERRUPT_STATUS_REGISTER] &= ~val;
306     can_update_irq(s);
307 
308     return 0;
309 }
310 
311 static void can_config_reset(XlnxZynqMPCANState *s)
312 {
313     /* Reset all the configuration registers. */
314     register_reset(&s->reg_info[R_SOFTWARE_RESET_REGISTER]);
315     register_reset(&s->reg_info[R_MODE_SELECT_REGISTER]);
316     register_reset(
317               &s->reg_info[R_ARBITRATION_PHASE_BAUD_RATE_PRESCALER_REGISTER]);
318     register_reset(&s->reg_info[R_ARBITRATION_PHASE_BIT_TIMING_REGISTER]);
319     register_reset(&s->reg_info[R_STATUS_REGISTER]);
320     register_reset(&s->reg_info[R_INTERRUPT_STATUS_REGISTER]);
321     register_reset(&s->reg_info[R_INTERRUPT_ENABLE_REGISTER]);
322     register_reset(&s->reg_info[R_INTERRUPT_CLEAR_REGISTER]);
323     register_reset(&s->reg_info[R_WIR]);
324 }
325 
326 static void can_config_mode(XlnxZynqMPCANState *s)
327 {
328     register_reset(&s->reg_info[R_ERROR_COUNTER_REGISTER]);
329     register_reset(&s->reg_info[R_ERROR_STATUS_REGISTER]);
330 
331     /* Put XlnxZynqMPCAN in configuration mode. */
332     ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, CONFIG, 1);
333     ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, WKUP, 0);
334     ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, SLP, 0);
335     ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, BSOFF, 0);
336     ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, ERROR, 0);
337     ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, RXOFLW, 0);
338     ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, RXOK, 0);
339     ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, TXOK, 0);
340     ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, ARBLST, 0);
341 
342     can_update_irq(s);
343 }
344 
345 static void update_status_register_mode_bits(XlnxZynqMPCANState *s)
346 {
347     bool sleep_status = ARRAY_FIELD_EX32(s->regs, STATUS_REGISTER, SLEEP);
348     bool sleep_mode = ARRAY_FIELD_EX32(s->regs, MODE_SELECT_REGISTER, SLEEP);
349     /* Wake up interrupt bit. */
350     bool wakeup_irq_val = sleep_status && (sleep_mode == 0);
351     /* Sleep interrupt bit. */
352     bool sleep_irq_val = sleep_mode && (sleep_status == 0);
353 
354     /* Clear previous core mode status bits. */
355     ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, LBACK, 0);
356     ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, SLEEP, 0);
357     ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, SNOOP, 0);
358     ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, NORMAL, 0);
359 
360     /* set current mode bit and generate irqs accordingly. */
361     if (ARRAY_FIELD_EX32(s->regs, MODE_SELECT_REGISTER, LBACK)) {
362         ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, LBACK, 1);
363     } else if (ARRAY_FIELD_EX32(s->regs, MODE_SELECT_REGISTER, SLEEP)) {
364         ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, SLEEP, 1);
365         ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, SLP,
366                          sleep_irq_val);
367     } else if (ARRAY_FIELD_EX32(s->regs, MODE_SELECT_REGISTER, SNOOP)) {
368         ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, SNOOP, 1);
369     } else {
370         /*
371          * If all bits are zero then XlnxZynqMPCAN is set in normal mode.
372          */
373         ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, NORMAL, 1);
374         /* Set wakeup interrupt bit. */
375         ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, WKUP,
376                          wakeup_irq_val);
377     }
378 
379     can_update_irq(s);
380 }
381 
382 static void can_exit_sleep_mode(XlnxZynqMPCANState *s)
383 {
384     ARRAY_FIELD_DP32(s->regs, MODE_SELECT_REGISTER, SLEEP, 0);
385     update_status_register_mode_bits(s);
386 }
387 
388 static void generate_frame(qemu_can_frame *frame, uint32_t *data)
389 {
390     frame->can_id = data[0];
391     frame->can_dlc = FIELD_EX32(data[1], TXFIFO_DLC, DLC);
392 
393     frame->data[0] = FIELD_EX32(data[2], TXFIFO_DATA1, DB3);
394     frame->data[1] = FIELD_EX32(data[2], TXFIFO_DATA1, DB2);
395     frame->data[2] = FIELD_EX32(data[2], TXFIFO_DATA1, DB1);
396     frame->data[3] = FIELD_EX32(data[2], TXFIFO_DATA1, DB0);
397 
398     frame->data[4] = FIELD_EX32(data[3], TXFIFO_DATA2, DB7);
399     frame->data[5] = FIELD_EX32(data[3], TXFIFO_DATA2, DB6);
400     frame->data[6] = FIELD_EX32(data[3], TXFIFO_DATA2, DB5);
401     frame->data[7] = FIELD_EX32(data[3], TXFIFO_DATA2, DB4);
402 }
403 
404 static bool tx_ready_check(XlnxZynqMPCANState *s)
405 {
406     if (ARRAY_FIELD_EX32(s->regs, SOFTWARE_RESET_REGISTER, SRST)) {
407         g_autofree char *path = object_get_canonical_path(OBJECT(s));
408 
409         qemu_log_mask(LOG_GUEST_ERROR, "%s: Attempting to transfer data while"
410                       " data while controller is in reset mode.\n",
411                       path);
412         return false;
413     }
414 
415     if (ARRAY_FIELD_EX32(s->regs, SOFTWARE_RESET_REGISTER, CEN) == 0) {
416         g_autofree char *path = object_get_canonical_path(OBJECT(s));
417 
418         qemu_log_mask(LOG_GUEST_ERROR, "%s: Attempting to transfer"
419                       " data while controller is in configuration mode. Reset"
420                       " the core so operations can start fresh.\n",
421                       path);
422         return false;
423     }
424 
425     if (ARRAY_FIELD_EX32(s->regs, STATUS_REGISTER, SNOOP)) {
426         g_autofree char *path = object_get_canonical_path(OBJECT(s));
427 
428         qemu_log_mask(LOG_GUEST_ERROR, "%s: Attempting to transfer"
429                       " data while controller is in SNOOP MODE.\n",
430                       path);
431         return false;
432     }
433 
434     return true;
435 }
436 
437 static void read_tx_frame(XlnxZynqMPCANState *s, Fifo32 *fifo, uint32_t *data)
438 {
439     unsigned used = fifo32_num_used(fifo);
440     bool is_txhpb = fifo == &s->txhpb_fifo;
441 
442     assert(used > 0);
443     used %= CAN_FRAME_SIZE;
444 
445     /*
446      * Frame Message Format
447      *
448      * Each frame includes four words (16 bytes). Software must read and write
449      * all four words regardless of the actual number of data bytes and valid
450      * fields in the message.
451      * If software misbehave (not writing all four words), we use the previous
452      * registers content to initialize each missing word.
453      *
454      * If used is 1 then ID, DLC and DATA1 are missing.
455      * if used is 2 then ID and DLC are missing.
456      * if used is 3 then only ID is missing.
457      */
458      if (used > 0) {
459         data[0] = s->regs[is_txhpb ? R_TXHPB_ID : R_TXFIFO_ID];
460     } else {
461         data[0] = fifo32_pop(fifo);
462     }
463     if (used == 1 || used == 2) {
464         data[1] = s->regs[is_txhpb ? R_TXHPB_DLC : R_TXFIFO_DLC];
465     } else {
466         data[1] = fifo32_pop(fifo);
467     }
468     if (used == 1) {
469         data[2] = s->regs[is_txhpb ? R_TXHPB_DATA1 : R_TXFIFO_DATA1];
470     } else {
471         data[2] = fifo32_pop(fifo);
472     }
473     /* DATA2 triggered the transfer thus is always available */
474     data[3] = fifo32_pop(fifo);
475 
476     if (used) {
477         qemu_log_mask(LOG_GUEST_ERROR,
478                       "%s: Incomplete CAN frame (only %u/%u slots used)\n",
479                       TYPE_XLNX_ZYNQMP_CAN, used, CAN_FRAME_SIZE);
480     }
481 }
482 
483 static void transfer_fifo(XlnxZynqMPCANState *s, Fifo32 *fifo)
484 {
485     qemu_can_frame frame;
486     uint32_t data[CAN_FRAME_SIZE];
487     int i;
488     bool can_tx = tx_ready_check(s);
489 
490     if (!can_tx) {
491         g_autofree char *path = object_get_canonical_path(OBJECT(s));
492 
493         qemu_log_mask(LOG_GUEST_ERROR, "%s: Controller is not enabled for data"
494                       " transfer.\n", path);
495         can_update_irq(s);
496         return;
497     }
498 
499     while (!fifo32_is_empty(fifo)) {
500         read_tx_frame(s, fifo, data);
501 
502         if (ARRAY_FIELD_EX32(s->regs, STATUS_REGISTER, LBACK)) {
503             /*
504              * Controller is in loopback. In Loopback mode, the CAN core
505              * transmits a recessive bitstream on to the XlnxZynqMPCAN Bus.
506              * Any message transmitted is looped back to the RX line and
507              * acknowledged. The XlnxZynqMPCAN core receives any message
508              * that it transmits.
509              */
510             if (fifo32_is_full(&s->rx_fifo)) {
511                 ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, RXOFLW, 1);
512             } else {
513                 for (i = 0; i < CAN_FRAME_SIZE; i++) {
514                     fifo32_push(&s->rx_fifo, data[i]);
515                 }
516 
517                 ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, RXOK, 1);
518             }
519         } else {
520             /* Normal mode Tx. */
521             generate_frame(&frame, data);
522 
523             trace_xlnx_can_tx_data(frame.can_id, frame.can_dlc,
524                                    frame.data[0], frame.data[1],
525                                    frame.data[2], frame.data[3],
526                                    frame.data[4], frame.data[5],
527                                    frame.data[6], frame.data[7]);
528             can_bus_client_send(&s->bus_client, &frame, 1);
529         }
530     }
531 
532     ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, TXOK, 1);
533     ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, TXBFLL, 0);
534 
535     if (ARRAY_FIELD_EX32(s->regs, STATUS_REGISTER, SLEEP)) {
536         can_exit_sleep_mode(s);
537     }
538 
539     can_update_irq(s);
540 }
541 
542 static uint64_t can_srr_pre_write(RegisterInfo *reg, uint64_t val)
543 {
544     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
545 
546     ARRAY_FIELD_DP32(s->regs, SOFTWARE_RESET_REGISTER, CEN,
547                      FIELD_EX32(val, SOFTWARE_RESET_REGISTER, CEN));
548 
549     if (FIELD_EX32(val, SOFTWARE_RESET_REGISTER, SRST)) {
550         trace_xlnx_can_reset(val);
551 
552         /* First, core will do software reset then will enter in config mode. */
553         can_config_reset(s);
554     }
555 
556     if (ARRAY_FIELD_EX32(s->regs, SOFTWARE_RESET_REGISTER, CEN) == 0) {
557         can_config_mode(s);
558     } else {
559         /*
560          * Leave config mode. Now XlnxZynqMPCAN core will enter normal,
561          * sleep, snoop or loopback mode depending upon LBACK, SLEEP, SNOOP
562          * register states.
563          */
564         ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, CONFIG, 0);
565 
566         ptimer_transaction_begin(s->can_timer);
567         ptimer_set_count(s->can_timer, 0);
568         ptimer_transaction_commit(s->can_timer);
569 
570         /* XlnxZynqMPCAN is out of config mode. It will send pending data. */
571         transfer_fifo(s, &s->txhpb_fifo);
572         transfer_fifo(s, &s->tx_fifo);
573     }
574 
575     update_status_register_mode_bits(s);
576 
577     return s->regs[R_SOFTWARE_RESET_REGISTER];
578 }
579 
580 static uint64_t can_msr_pre_write(RegisterInfo *reg, uint64_t val)
581 {
582     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
583     uint8_t multi_mode;
584 
585     /*
586      * Multiple mode set check. This is done to make sure user doesn't set
587      * multiple modes.
588      */
589     multi_mode = FIELD_EX32(val, MODE_SELECT_REGISTER, LBACK) +
590                  FIELD_EX32(val, MODE_SELECT_REGISTER, SLEEP) +
591                  FIELD_EX32(val, MODE_SELECT_REGISTER, SNOOP);
592 
593     if (multi_mode > 1) {
594         g_autofree char *path = object_get_canonical_path(OBJECT(s));
595 
596         qemu_log_mask(LOG_GUEST_ERROR, "%s: Attempting to config"
597                       " several modes simultaneously. One mode will be selected"
598                       " according to their priority: LBACK > SLEEP > SNOOP.\n",
599                       path);
600     }
601 
602     if (ARRAY_FIELD_EX32(s->regs, SOFTWARE_RESET_REGISTER, CEN) == 0) {
603         /* We are in configuration mode, any mode can be selected. */
604         s->regs[R_MODE_SELECT_REGISTER] = val;
605     } else {
606         bool sleep_mode_bit = FIELD_EX32(val, MODE_SELECT_REGISTER, SLEEP);
607 
608         ARRAY_FIELD_DP32(s->regs, MODE_SELECT_REGISTER, SLEEP, sleep_mode_bit);
609 
610         if (FIELD_EX32(val, MODE_SELECT_REGISTER, LBACK)) {
611             g_autofree char *path = object_get_canonical_path(OBJECT(s));
612 
613             qemu_log_mask(LOG_GUEST_ERROR, "%s: Attempting to set"
614                           " LBACK mode without setting CEN bit as 0.\n",
615                           path);
616         } else if (FIELD_EX32(val, MODE_SELECT_REGISTER, SNOOP)) {
617             g_autofree char *path = object_get_canonical_path(OBJECT(s));
618 
619             qemu_log_mask(LOG_GUEST_ERROR, "%s: Attempting to set"
620                           " SNOOP mode without setting CEN bit as 0.\n",
621                           path);
622         }
623 
624         update_status_register_mode_bits(s);
625     }
626 
627     return s->regs[R_MODE_SELECT_REGISTER];
628 }
629 
630 static uint64_t can_brpr_pre_write(RegisterInfo  *reg, uint64_t val)
631 {
632     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
633 
634     /* Only allow writes when in config mode. */
635     if (ARRAY_FIELD_EX32(s->regs, SOFTWARE_RESET_REGISTER, CEN)) {
636         return s->regs[R_ARBITRATION_PHASE_BAUD_RATE_PRESCALER_REGISTER];
637     }
638 
639     return val;
640 }
641 
642 static uint64_t can_btr_pre_write(RegisterInfo  *reg, uint64_t val)
643 {
644     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
645 
646     /* Only allow writes when in config mode. */
647     if (ARRAY_FIELD_EX32(s->regs, SOFTWARE_RESET_REGISTER, CEN)) {
648         return s->regs[R_ARBITRATION_PHASE_BIT_TIMING_REGISTER];
649     }
650 
651     return val;
652 }
653 
654 static uint64_t can_tcr_pre_write(RegisterInfo  *reg, uint64_t val)
655 {
656     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
657 
658     if (FIELD_EX32(val, TIMESTAMP_REGISTER, CTS)) {
659         ptimer_transaction_begin(s->can_timer);
660         ptimer_set_count(s->can_timer, 0);
661         ptimer_transaction_commit(s->can_timer);
662     }
663 
664     return 0;
665 }
666 
667 static void update_rx_fifo(XlnxZynqMPCANState *s, const qemu_can_frame *frame)
668 {
669     bool filter_pass = false;
670     uint16_t timestamp = 0;
671 
672     /* If no filter is enabled. Message will be stored in FIFO. */
673     if (!((ARRAY_FIELD_EX32(s->regs, AFR, UAF1)) |
674        (ARRAY_FIELD_EX32(s->regs, AFR, UAF2)) |
675        (ARRAY_FIELD_EX32(s->regs, AFR, UAF3)) |
676        (ARRAY_FIELD_EX32(s->regs, AFR, UAF4)))) {
677         filter_pass = true;
678     }
679 
680     /*
681      * Messages that pass any of the acceptance filters will be stored in
682      * the RX FIFO.
683      */
684     if (ARRAY_FIELD_EX32(s->regs, AFR, UAF1)) {
685         uint32_t id_masked = s->regs[R_AFMR1] & frame->can_id;
686         uint32_t filter_id_masked = s->regs[R_AFMR1] & s->regs[R_AFIR1];
687 
688         if (filter_id_masked == id_masked) {
689             filter_pass = true;
690         }
691     }
692 
693     if (ARRAY_FIELD_EX32(s->regs, AFR, UAF2)) {
694         uint32_t id_masked = s->regs[R_AFMR2] & frame->can_id;
695         uint32_t filter_id_masked = s->regs[R_AFMR2] & s->regs[R_AFIR2];
696 
697         if (filter_id_masked == id_masked) {
698             filter_pass = true;
699         }
700     }
701 
702     if (ARRAY_FIELD_EX32(s->regs, AFR, UAF3)) {
703         uint32_t id_masked = s->regs[R_AFMR3] & frame->can_id;
704         uint32_t filter_id_masked = s->regs[R_AFMR3] & s->regs[R_AFIR3];
705 
706         if (filter_id_masked == id_masked) {
707             filter_pass = true;
708         }
709     }
710 
711     if (ARRAY_FIELD_EX32(s->regs, AFR, UAF4)) {
712         uint32_t id_masked = s->regs[R_AFMR4] & frame->can_id;
713         uint32_t filter_id_masked = s->regs[R_AFMR4] & s->regs[R_AFIR4];
714 
715         if (filter_id_masked == id_masked) {
716             filter_pass = true;
717         }
718     }
719 
720     if (!filter_pass) {
721         trace_xlnx_can_rx_fifo_filter_reject(frame->can_id, frame->can_dlc);
722         return;
723     }
724 
725     /* Store the message in fifo if it passed through any of the filters. */
726     if (filter_pass && frame->can_dlc <= MAX_DLC) {
727 
728         if (fifo32_is_full(&s->rx_fifo)) {
729             ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, RXOFLW, 1);
730         } else {
731             timestamp = CAN_TIMER_MAX - ptimer_get_count(s->can_timer);
732 
733             fifo32_push(&s->rx_fifo, frame->can_id);
734 
735             fifo32_push(&s->rx_fifo, deposit32(0, R_RXFIFO_DLC_DLC_SHIFT,
736                                                R_RXFIFO_DLC_DLC_LENGTH,
737                                                frame->can_dlc) |
738                                      deposit32(0, R_RXFIFO_DLC_RXT_SHIFT,
739                                                R_RXFIFO_DLC_RXT_LENGTH,
740                                                timestamp));
741 
742             /* First 32 bit of the data. */
743             fifo32_push(&s->rx_fifo, deposit32(0, R_RXFIFO_DATA1_DB3_SHIFT,
744                                                R_RXFIFO_DATA1_DB3_LENGTH,
745                                                frame->data[0]) |
746                                      deposit32(0, R_RXFIFO_DATA1_DB2_SHIFT,
747                                                R_RXFIFO_DATA1_DB2_LENGTH,
748                                                frame->data[1]) |
749                                      deposit32(0, R_RXFIFO_DATA1_DB1_SHIFT,
750                                                R_RXFIFO_DATA1_DB1_LENGTH,
751                                                frame->data[2]) |
752                                      deposit32(0, R_RXFIFO_DATA1_DB0_SHIFT,
753                                                R_RXFIFO_DATA1_DB0_LENGTH,
754                                                frame->data[3]));
755             /* Last 32 bit of the data. */
756             fifo32_push(&s->rx_fifo, deposit32(0, R_RXFIFO_DATA2_DB7_SHIFT,
757                                                R_RXFIFO_DATA2_DB7_LENGTH,
758                                                frame->data[4]) |
759                                      deposit32(0, R_RXFIFO_DATA2_DB6_SHIFT,
760                                                R_RXFIFO_DATA2_DB6_LENGTH,
761                                                frame->data[5]) |
762                                      deposit32(0, R_RXFIFO_DATA2_DB5_SHIFT,
763                                                R_RXFIFO_DATA2_DB5_LENGTH,
764                                                frame->data[6]) |
765                                      deposit32(0, R_RXFIFO_DATA2_DB4_SHIFT,
766                                                R_RXFIFO_DATA2_DB4_LENGTH,
767                                                frame->data[7]));
768 
769             ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, RXOK, 1);
770             trace_xlnx_can_rx_data(frame->can_id, frame->can_dlc,
771                                    frame->data[0], frame->data[1],
772                                    frame->data[2], frame->data[3],
773                                    frame->data[4], frame->data[5],
774                                    frame->data[6], frame->data[7]);
775         }
776 
777         can_update_irq(s);
778     }
779 }
780 
781 static uint64_t can_rxfifo_post_read_id(RegisterInfo *reg, uint64_t val)
782 {
783     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
784     unsigned used = fifo32_num_used(&s->rx_fifo);
785 
786     if (used < CAN_FRAME_SIZE) {
787         ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, RXUFLW, 1);
788     } else {
789         val = s->regs[R_RXFIFO_ID] = fifo32_pop(&s->rx_fifo);
790         s->regs[R_RXFIFO_DLC] = fifo32_pop(&s->rx_fifo);
791         s->regs[R_RXFIFO_DATA1] = fifo32_pop(&s->rx_fifo);
792         s->regs[R_RXFIFO_DATA2] = fifo32_pop(&s->rx_fifo);
793     }
794 
795     can_update_irq(s);
796     return val;
797 }
798 
799 static void can_filter_enable_post_write(RegisterInfo *reg, uint64_t val)
800 {
801     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
802 
803     if (ARRAY_FIELD_EX32(s->regs, AFR, UAF1) &&
804         ARRAY_FIELD_EX32(s->regs, AFR, UAF2) &&
805         ARRAY_FIELD_EX32(s->regs, AFR, UAF3) &&
806         ARRAY_FIELD_EX32(s->regs, AFR, UAF4)) {
807         ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, ACFBSY, 1);
808     } else {
809         ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, ACFBSY, 0);
810     }
811 }
812 
813 static uint64_t can_filter_mask_pre_write(RegisterInfo *reg, uint64_t val)
814 {
815     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
816     uint32_t reg_idx = (reg->access->addr) / 4;
817     uint32_t filter_number = (reg_idx - R_AFMR1) / 2;
818 
819     /* modify an acceptance filter, the corresponding UAF bit should be '0'. */
820     if (!(s->regs[R_AFR] & (1 << filter_number))) {
821         s->regs[reg_idx] = val;
822 
823         trace_xlnx_can_filter_mask_pre_write(filter_number, s->regs[reg_idx]);
824     } else {
825         g_autofree char *path = object_get_canonical_path(OBJECT(s));
826 
827         qemu_log_mask(LOG_GUEST_ERROR, "%s: Acceptance filter %d"
828                       " mask is not set as corresponding UAF bit is not 0.\n",
829                       path, filter_number + 1);
830     }
831 
832     return s->regs[reg_idx];
833 }
834 
835 static uint64_t can_filter_id_pre_write(RegisterInfo *reg, uint64_t val)
836 {
837     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
838     uint32_t reg_idx = (reg->access->addr) / 4;
839     uint32_t filter_number = (reg_idx - R_AFIR1) / 2;
840 
841     if (!(s->regs[R_AFR] & (1 << filter_number))) {
842         s->regs[reg_idx] = val;
843 
844         trace_xlnx_can_filter_id_pre_write(filter_number, s->regs[reg_idx]);
845     } else {
846         g_autofree char *path = object_get_canonical_path(OBJECT(s));
847 
848         qemu_log_mask(LOG_GUEST_ERROR, "%s: Acceptance filter %d"
849                       " id is not set as corresponding UAF bit is not 0.\n",
850                       path, filter_number + 1);
851     }
852 
853     return s->regs[reg_idx];
854 }
855 
856 static void can_tx_post_write(RegisterInfo *reg, uint64_t val)
857 {
858     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
859 
860     bool is_txhpb = reg->access->addr > A_TXFIFO_DATA2;
861 
862     bool initiate_transfer = (reg->access->addr == A_TXFIFO_DATA2) ||
863                              (reg->access->addr == A_TXHPB_DATA2);
864 
865     Fifo32 *f = is_txhpb ? &s->txhpb_fifo : &s->tx_fifo;
866 
867     if (!fifo32_is_full(f)) {
868         fifo32_push(f, val);
869     } else {
870         g_autofree char *path = object_get_canonical_path(OBJECT(s));
871 
872         qemu_log_mask(LOG_GUEST_ERROR, "%s: TX FIFO is full.\n", path);
873     }
874 
875     /* Initiate the message send if TX register is written. */
876     if (initiate_transfer &&
877         ARRAY_FIELD_EX32(s->regs, SOFTWARE_RESET_REGISTER, CEN)) {
878         transfer_fifo(s, f);
879     }
880 
881     can_update_irq(s);
882 }
883 
884 static const RegisterAccessInfo can_regs_info[] = {
885     {   .name = "SOFTWARE_RESET_REGISTER",
886         .addr = A_SOFTWARE_RESET_REGISTER,
887         .rsvd = 0xfffffffc,
888         .pre_write = can_srr_pre_write,
889     },{ .name = "MODE_SELECT_REGISTER",
890         .addr = A_MODE_SELECT_REGISTER,
891         .rsvd = 0xfffffff8,
892         .pre_write = can_msr_pre_write,
893     },{ .name = "ARBITRATION_PHASE_BAUD_RATE_PRESCALER_REGISTER",
894         .addr = A_ARBITRATION_PHASE_BAUD_RATE_PRESCALER_REGISTER,
895         .rsvd = 0xffffff00,
896         .pre_write = can_brpr_pre_write,
897     },{ .name = "ARBITRATION_PHASE_BIT_TIMING_REGISTER",
898         .addr = A_ARBITRATION_PHASE_BIT_TIMING_REGISTER,
899         .rsvd = 0xfffffe00,
900         .pre_write = can_btr_pre_write,
901     },{ .name = "ERROR_COUNTER_REGISTER",
902         .addr = A_ERROR_COUNTER_REGISTER,
903         .rsvd = 0xffff0000,
904         .ro = 0xffffffff,
905     },{ .name = "ERROR_STATUS_REGISTER",
906         .addr = A_ERROR_STATUS_REGISTER,
907         .rsvd = 0xffffffe0,
908         .w1c = 0x1f,
909     },{ .name = "STATUS_REGISTER",  .addr = A_STATUS_REGISTER,
910         .reset = 0x1,
911         .rsvd = 0xffffe000,
912         .ro = 0x1fff,
913     },{ .name = "INTERRUPT_STATUS_REGISTER",
914         .addr = A_INTERRUPT_STATUS_REGISTER,
915         .reset = 0x6000,
916         .rsvd = 0xffff8000,
917         .ro = 0x7fff,
918     },{ .name = "INTERRUPT_ENABLE_REGISTER",
919         .addr = A_INTERRUPT_ENABLE_REGISTER,
920         .rsvd = 0xffff8000,
921         .post_write = can_ier_post_write,
922     },{ .name = "INTERRUPT_CLEAR_REGISTER",
923         .addr = A_INTERRUPT_CLEAR_REGISTER,
924         .rsvd = 0xffff8000,
925         .pre_write = can_icr_pre_write,
926     },{ .name = "TIMESTAMP_REGISTER",
927         .addr = A_TIMESTAMP_REGISTER,
928         .rsvd = 0xfffffffe,
929         .pre_write = can_tcr_pre_write,
930     },{ .name = "WIR",  .addr = A_WIR,
931         .reset = 0x3f3f,
932         .rsvd = 0xffff0000,
933     },{ .name = "TXFIFO_ID",  .addr = A_TXFIFO_ID,
934         .post_write = can_tx_post_write,
935     },{ .name = "TXFIFO_DLC",  .addr = A_TXFIFO_DLC,
936         .rsvd = 0xfffffff,
937         .post_write = can_tx_post_write,
938     },{ .name = "TXFIFO_DATA1",  .addr = A_TXFIFO_DATA1,
939         .post_write = can_tx_post_write,
940     },{ .name = "TXFIFO_DATA2",  .addr = A_TXFIFO_DATA2,
941         .post_write = can_tx_post_write,
942     },{ .name = "TXHPB_ID",  .addr = A_TXHPB_ID,
943         .post_write = can_tx_post_write,
944     },{ .name = "TXHPB_DLC",  .addr = A_TXHPB_DLC,
945         .rsvd = 0xfffffff,
946         .post_write = can_tx_post_write,
947     },{ .name = "TXHPB_DATA1",  .addr = A_TXHPB_DATA1,
948         .post_write = can_tx_post_write,
949     },{ .name = "TXHPB_DATA2",  .addr = A_TXHPB_DATA2,
950         .post_write = can_tx_post_write,
951     },{ .name = "RXFIFO_ID",  .addr = A_RXFIFO_ID,
952         .ro = 0xffffffff,
953         .post_read = can_rxfifo_post_read_id,
954     },{ .name = "RXFIFO_DLC",  .addr = A_RXFIFO_DLC,
955         .rsvd = 0xfff0000,
956     },{ .name = "RXFIFO_DATA1",  .addr = A_RXFIFO_DATA1,
957     },{ .name = "RXFIFO_DATA2",  .addr = A_RXFIFO_DATA2,
958     },{ .name = "AFR",  .addr = A_AFR,
959         .rsvd = 0xfffffff0,
960         .post_write = can_filter_enable_post_write,
961     },{ .name = "AFMR1",  .addr = A_AFMR1,
962         .pre_write = can_filter_mask_pre_write,
963     },{ .name = "AFIR1",  .addr = A_AFIR1,
964         .pre_write = can_filter_id_pre_write,
965     },{ .name = "AFMR2",  .addr = A_AFMR2,
966         .pre_write = can_filter_mask_pre_write,
967     },{ .name = "AFIR2",  .addr = A_AFIR2,
968         .pre_write = can_filter_id_pre_write,
969     },{ .name = "AFMR3",  .addr = A_AFMR3,
970         .pre_write = can_filter_mask_pre_write,
971     },{ .name = "AFIR3",  .addr = A_AFIR3,
972         .pre_write = can_filter_id_pre_write,
973     },{ .name = "AFMR4",  .addr = A_AFMR4,
974         .pre_write = can_filter_mask_pre_write,
975     },{ .name = "AFIR4",  .addr = A_AFIR4,
976         .pre_write = can_filter_id_pre_write,
977     }
978 };
979 
980 static void xlnx_zynqmp_can_ptimer_cb(void *opaque)
981 {
982     /* No action required on the timer rollover. */
983 }
984 
985 static const MemoryRegionOps can_ops = {
986     .read = register_read_memory,
987     .write = register_write_memory,
988     .endianness = DEVICE_LITTLE_ENDIAN,
989     .valid = {
990         .min_access_size = 4,
991         .max_access_size = 4,
992     },
993 };
994 
995 static void xlnx_zynqmp_can_reset_init(Object *obj, ResetType type)
996 {
997     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(obj);
998     unsigned int i;
999 
1000     for (i = R_RXFIFO_ID; i < ARRAY_SIZE(s->reg_info); ++i) {
1001         register_reset(&s->reg_info[i]);
1002     }
1003 
1004     ptimer_transaction_begin(s->can_timer);
1005     ptimer_set_count(s->can_timer, 0);
1006     ptimer_transaction_commit(s->can_timer);
1007 }
1008 
1009 static void xlnx_zynqmp_can_reset_hold(Object *obj, ResetType type)
1010 {
1011     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(obj);
1012     unsigned int i;
1013 
1014     for (i = 0; i < R_RXFIFO_ID; ++i) {
1015         register_reset(&s->reg_info[i]);
1016     }
1017 
1018     /*
1019      * Reset FIFOs when CAN model is reset. This will clear the fifo writes
1020      * done by post_write which gets called from register_reset function,
1021      * post_write handle will not be able to trigger tx because CAN will be
1022      * disabled when software_reset_register is cleared first.
1023      */
1024     fifo32_reset(&s->rx_fifo);
1025     fifo32_reset(&s->tx_fifo);
1026     fifo32_reset(&s->txhpb_fifo);
1027 }
1028 
1029 static bool xlnx_zynqmp_can_can_receive(CanBusClientState *client)
1030 {
1031     XlnxZynqMPCANState *s = container_of(client, XlnxZynqMPCANState,
1032                                          bus_client);
1033 
1034     if (ARRAY_FIELD_EX32(s->regs, SOFTWARE_RESET_REGISTER, SRST)) {
1035         g_autofree char *path = object_get_canonical_path(OBJECT(s));
1036 
1037         qemu_log_mask(LOG_GUEST_ERROR, "%s: Controller is in reset state.\n",
1038                       path);
1039         return false;
1040     }
1041 
1042     if ((ARRAY_FIELD_EX32(s->regs, SOFTWARE_RESET_REGISTER, CEN)) == 0) {
1043         g_autofree char *path = object_get_canonical_path(OBJECT(s));
1044 
1045         qemu_log_mask(LOG_GUEST_ERROR, "%s: Controller is disabled. Incoming"
1046                       " messages will be discarded.\n", path);
1047         return false;
1048     }
1049 
1050     return true;
1051 }
1052 
1053 static ssize_t xlnx_zynqmp_can_receive(CanBusClientState *client,
1054                                const qemu_can_frame *buf, size_t buf_size) {
1055     XlnxZynqMPCANState *s = container_of(client, XlnxZynqMPCANState,
1056                                          bus_client);
1057     const qemu_can_frame *frame = buf;
1058 
1059     if (buf_size <= 0) {
1060         g_autofree char *path = object_get_canonical_path(OBJECT(s));
1061 
1062         qemu_log_mask(LOG_GUEST_ERROR, "%s: Error in the data received.\n",
1063                       path);
1064         return 0;
1065     }
1066 
1067     if (ARRAY_FIELD_EX32(s->regs, STATUS_REGISTER, SNOOP)) {
1068         /* Snoop Mode: Just keep the data. no response back. */
1069         update_rx_fifo(s, frame);
1070     } else if ((ARRAY_FIELD_EX32(s->regs, STATUS_REGISTER, SLEEP))) {
1071         /*
1072          * XlnxZynqMPCAN is in sleep mode. Any data on bus will bring it to wake
1073          * up state.
1074          */
1075         can_exit_sleep_mode(s);
1076         update_rx_fifo(s, frame);
1077     } else if ((ARRAY_FIELD_EX32(s->regs, STATUS_REGISTER, SLEEP)) == 0) {
1078         update_rx_fifo(s, frame);
1079     } else {
1080         /*
1081          * XlnxZynqMPCAN will not participate in normal bus communication
1082          * and will not receive any messages transmitted by other CAN nodes.
1083          */
1084         trace_xlnx_can_rx_discard(s->regs[R_STATUS_REGISTER]);
1085     }
1086 
1087     return 1;
1088 }
1089 
1090 static CanBusClientInfo can_xilinx_bus_client_info = {
1091     .can_receive = xlnx_zynqmp_can_can_receive,
1092     .receive = xlnx_zynqmp_can_receive,
1093 };
1094 
1095 static int xlnx_zynqmp_can_connect_to_bus(XlnxZynqMPCANState *s,
1096                                           CanBusState *bus)
1097 {
1098     s->bus_client.info = &can_xilinx_bus_client_info;
1099 
1100     if (can_bus_insert_client(bus, &s->bus_client) < 0) {
1101         return -1;
1102     }
1103     return 0;
1104 }
1105 
1106 static void xlnx_zynqmp_can_realize(DeviceState *dev, Error **errp)
1107 {
1108     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(dev);
1109 
1110     if (s->canbus) {
1111         if (xlnx_zynqmp_can_connect_to_bus(s, s->canbus) < 0) {
1112             g_autofree char *path = object_get_canonical_path(OBJECT(s));
1113 
1114             error_setg(errp, "%s: xlnx_zynqmp_can_connect_to_bus"
1115                        " failed.", path);
1116             return;
1117         }
1118     }
1119 
1120     /* Create RX FIFO, TXFIFO, TXHPB storage. */
1121     fifo32_create(&s->rx_fifo, RXFIFO_SIZE);
1122     fifo32_create(&s->tx_fifo, RXFIFO_SIZE);
1123     fifo32_create(&s->txhpb_fifo, CAN_FRAME_SIZE);
1124 
1125     /* Allocate a new timer. */
1126     s->can_timer = ptimer_init(xlnx_zynqmp_can_ptimer_cb, s,
1127                                PTIMER_POLICY_LEGACY);
1128 
1129     ptimer_transaction_begin(s->can_timer);
1130 
1131     ptimer_set_freq(s->can_timer, s->cfg.ext_clk_freq);
1132     ptimer_set_limit(s->can_timer, CAN_TIMER_MAX, 1);
1133     ptimer_run(s->can_timer, 0);
1134     ptimer_transaction_commit(s->can_timer);
1135 }
1136 
1137 static void xlnx_zynqmp_can_init(Object *obj)
1138 {
1139     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(obj);
1140     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
1141 
1142     RegisterInfoArray *reg_array;
1143 
1144     memory_region_init(&s->iomem, obj, TYPE_XLNX_ZYNQMP_CAN,
1145                         XLNX_ZYNQMP_CAN_R_MAX * 4);
1146     reg_array = register_init_block32(DEVICE(obj), can_regs_info,
1147                                ARRAY_SIZE(can_regs_info),
1148                                s->reg_info, s->regs,
1149                                &can_ops,
1150                                XLNX_ZYNQMP_CAN_ERR_DEBUG,
1151                                XLNX_ZYNQMP_CAN_R_MAX * 4);
1152 
1153     memory_region_add_subregion(&s->iomem, 0x00, &reg_array->mem);
1154     sysbus_init_mmio(sbd, &s->iomem);
1155     sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->irq);
1156 }
1157 
1158 static const VMStateDescription vmstate_can = {
1159     .name = TYPE_XLNX_ZYNQMP_CAN,
1160     .version_id = 1,
1161     .minimum_version_id = 1,
1162     .fields = (const VMStateField[]) {
1163         VMSTATE_FIFO32(rx_fifo, XlnxZynqMPCANState),
1164         VMSTATE_FIFO32(tx_fifo, XlnxZynqMPCANState),
1165         VMSTATE_FIFO32(txhpb_fifo, XlnxZynqMPCANState),
1166         VMSTATE_UINT32_ARRAY(regs, XlnxZynqMPCANState, XLNX_ZYNQMP_CAN_R_MAX),
1167         VMSTATE_PTIMER(can_timer, XlnxZynqMPCANState),
1168         VMSTATE_END_OF_LIST(),
1169     }
1170 };
1171 
1172 static Property xlnx_zynqmp_can_properties[] = {
1173     DEFINE_PROP_UINT32("ext_clk_freq", XlnxZynqMPCANState, cfg.ext_clk_freq,
1174                        CAN_DEFAULT_CLOCK),
1175     DEFINE_PROP_LINK("canbus", XlnxZynqMPCANState, canbus, TYPE_CAN_BUS,
1176                      CanBusState *),
1177     DEFINE_PROP_END_OF_LIST(),
1178 };
1179 
1180 static void xlnx_zynqmp_can_class_init(ObjectClass *klass, void *data)
1181 {
1182     DeviceClass *dc = DEVICE_CLASS(klass);
1183     ResettableClass *rc = RESETTABLE_CLASS(klass);
1184 
1185     rc->phases.enter = xlnx_zynqmp_can_reset_init;
1186     rc->phases.hold = xlnx_zynqmp_can_reset_hold;
1187     dc->realize = xlnx_zynqmp_can_realize;
1188     device_class_set_props(dc, xlnx_zynqmp_can_properties);
1189     dc->vmsd = &vmstate_can;
1190 }
1191 
1192 static const TypeInfo can_info = {
1193     .name          = TYPE_XLNX_ZYNQMP_CAN,
1194     .parent        = TYPE_SYS_BUS_DEVICE,
1195     .instance_size = sizeof(XlnxZynqMPCANState),
1196     .class_init    = xlnx_zynqmp_can_class_init,
1197     .instance_init = xlnx_zynqmp_can_init,
1198 };
1199 
1200 static void can_register_types(void)
1201 {
1202     type_register_static(&can_info);
1203 }
1204 
1205 type_init(can_register_types)
1206