xref: /openbmc/qemu/hw/net/can/xlnx-zynqmp-can.c (revision c63ca4ff)
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 "sysemu/sysemu.h"
41 #include "migration/vmstate.h"
42 #include "hw/qdev-properties.h"
43 #include "net/can_emu.h"
44 #include "net/can_host.h"
45 #include "qemu/event_notifier.h"
46 #include "qom/object_interfaces.h"
47 #include "hw/net/xlnx-zynqmp-can.h"
48 #include "trace.h"
49 
50 #ifndef XLNX_ZYNQMP_CAN_ERR_DEBUG
51 #define XLNX_ZYNQMP_CAN_ERR_DEBUG 0
52 #endif
53 
54 #define MAX_DLC            8
55 #undef ERROR
56 
57 REG32(SOFTWARE_RESET_REGISTER, 0x0)
58     FIELD(SOFTWARE_RESET_REGISTER, CEN, 1, 1)
59     FIELD(SOFTWARE_RESET_REGISTER, SRST, 0, 1)
60 REG32(MODE_SELECT_REGISTER, 0x4)
61     FIELD(MODE_SELECT_REGISTER, SNOOP, 2, 1)
62     FIELD(MODE_SELECT_REGISTER, LBACK, 1, 1)
63     FIELD(MODE_SELECT_REGISTER, SLEEP, 0, 1)
64 REG32(ARBITRATION_PHASE_BAUD_RATE_PRESCALER_REGISTER, 0x8)
65     FIELD(ARBITRATION_PHASE_BAUD_RATE_PRESCALER_REGISTER, BRP, 0, 8)
66 REG32(ARBITRATION_PHASE_BIT_TIMING_REGISTER, 0xc)
67     FIELD(ARBITRATION_PHASE_BIT_TIMING_REGISTER, SJW, 7, 2)
68     FIELD(ARBITRATION_PHASE_BIT_TIMING_REGISTER, TS2, 4, 3)
69     FIELD(ARBITRATION_PHASE_BIT_TIMING_REGISTER, TS1, 0, 4)
70 REG32(ERROR_COUNTER_REGISTER, 0x10)
71     FIELD(ERROR_COUNTER_REGISTER, REC, 8, 8)
72     FIELD(ERROR_COUNTER_REGISTER, TEC, 0, 8)
73 REG32(ERROR_STATUS_REGISTER, 0x14)
74     FIELD(ERROR_STATUS_REGISTER, ACKER, 4, 1)
75     FIELD(ERROR_STATUS_REGISTER, BERR, 3, 1)
76     FIELD(ERROR_STATUS_REGISTER, STER, 2, 1)
77     FIELD(ERROR_STATUS_REGISTER, FMER, 1, 1)
78     FIELD(ERROR_STATUS_REGISTER, CRCER, 0, 1)
79 REG32(STATUS_REGISTER, 0x18)
80     FIELD(STATUS_REGISTER, SNOOP, 12, 1)
81     FIELD(STATUS_REGISTER, ACFBSY, 11, 1)
82     FIELD(STATUS_REGISTER, TXFLL, 10, 1)
83     FIELD(STATUS_REGISTER, TXBFLL, 9, 1)
84     FIELD(STATUS_REGISTER, ESTAT, 7, 2)
85     FIELD(STATUS_REGISTER, ERRWRN, 6, 1)
86     FIELD(STATUS_REGISTER, BBSY, 5, 1)
87     FIELD(STATUS_REGISTER, BIDLE, 4, 1)
88     FIELD(STATUS_REGISTER, NORMAL, 3, 1)
89     FIELD(STATUS_REGISTER, SLEEP, 2, 1)
90     FIELD(STATUS_REGISTER, LBACK, 1, 1)
91     FIELD(STATUS_REGISTER, CONFIG, 0, 1)
92 REG32(INTERRUPT_STATUS_REGISTER, 0x1c)
93     FIELD(INTERRUPT_STATUS_REGISTER, TXFEMP, 14, 1)
94     FIELD(INTERRUPT_STATUS_REGISTER, TXFWMEMP, 13, 1)
95     FIELD(INTERRUPT_STATUS_REGISTER, RXFWMFLL, 12, 1)
96     FIELD(INTERRUPT_STATUS_REGISTER, WKUP, 11, 1)
97     FIELD(INTERRUPT_STATUS_REGISTER, SLP, 10, 1)
98     FIELD(INTERRUPT_STATUS_REGISTER, BSOFF, 9, 1)
99     FIELD(INTERRUPT_STATUS_REGISTER, ERROR, 8, 1)
100     FIELD(INTERRUPT_STATUS_REGISTER, RXNEMP, 7, 1)
101     FIELD(INTERRUPT_STATUS_REGISTER, RXOFLW, 6, 1)
102     FIELD(INTERRUPT_STATUS_REGISTER, RXUFLW, 5, 1)
103     FIELD(INTERRUPT_STATUS_REGISTER, RXOK, 4, 1)
104     FIELD(INTERRUPT_STATUS_REGISTER, TXBFLL, 3, 1)
105     FIELD(INTERRUPT_STATUS_REGISTER, TXFLL, 2, 1)
106     FIELD(INTERRUPT_STATUS_REGISTER, TXOK, 1, 1)
107     FIELD(INTERRUPT_STATUS_REGISTER, ARBLST, 0, 1)
108 REG32(INTERRUPT_ENABLE_REGISTER, 0x20)
109     FIELD(INTERRUPT_ENABLE_REGISTER, ETXFEMP, 14, 1)
110     FIELD(INTERRUPT_ENABLE_REGISTER, ETXFWMEMP, 13, 1)
111     FIELD(INTERRUPT_ENABLE_REGISTER, ERXFWMFLL, 12, 1)
112     FIELD(INTERRUPT_ENABLE_REGISTER, EWKUP, 11, 1)
113     FIELD(INTERRUPT_ENABLE_REGISTER, ESLP, 10, 1)
114     FIELD(INTERRUPT_ENABLE_REGISTER, EBSOFF, 9, 1)
115     FIELD(INTERRUPT_ENABLE_REGISTER, EERROR, 8, 1)
116     FIELD(INTERRUPT_ENABLE_REGISTER, ERXNEMP, 7, 1)
117     FIELD(INTERRUPT_ENABLE_REGISTER, ERXOFLW, 6, 1)
118     FIELD(INTERRUPT_ENABLE_REGISTER, ERXUFLW, 5, 1)
119     FIELD(INTERRUPT_ENABLE_REGISTER, ERXOK, 4, 1)
120     FIELD(INTERRUPT_ENABLE_REGISTER, ETXBFLL, 3, 1)
121     FIELD(INTERRUPT_ENABLE_REGISTER, ETXFLL, 2, 1)
122     FIELD(INTERRUPT_ENABLE_REGISTER, ETXOK, 1, 1)
123     FIELD(INTERRUPT_ENABLE_REGISTER, EARBLST, 0, 1)
124 REG32(INTERRUPT_CLEAR_REGISTER, 0x24)
125     FIELD(INTERRUPT_CLEAR_REGISTER, CTXFEMP, 14, 1)
126     FIELD(INTERRUPT_CLEAR_REGISTER, CTXFWMEMP, 13, 1)
127     FIELD(INTERRUPT_CLEAR_REGISTER, CRXFWMFLL, 12, 1)
128     FIELD(INTERRUPT_CLEAR_REGISTER, CWKUP, 11, 1)
129     FIELD(INTERRUPT_CLEAR_REGISTER, CSLP, 10, 1)
130     FIELD(INTERRUPT_CLEAR_REGISTER, CBSOFF, 9, 1)
131     FIELD(INTERRUPT_CLEAR_REGISTER, CERROR, 8, 1)
132     FIELD(INTERRUPT_CLEAR_REGISTER, CRXNEMP, 7, 1)
133     FIELD(INTERRUPT_CLEAR_REGISTER, CRXOFLW, 6, 1)
134     FIELD(INTERRUPT_CLEAR_REGISTER, CRXUFLW, 5, 1)
135     FIELD(INTERRUPT_CLEAR_REGISTER, CRXOK, 4, 1)
136     FIELD(INTERRUPT_CLEAR_REGISTER, CTXBFLL, 3, 1)
137     FIELD(INTERRUPT_CLEAR_REGISTER, CTXFLL, 2, 1)
138     FIELD(INTERRUPT_CLEAR_REGISTER, CTXOK, 1, 1)
139     FIELD(INTERRUPT_CLEAR_REGISTER, CARBLST, 0, 1)
140 REG32(TIMESTAMP_REGISTER, 0x28)
141     FIELD(TIMESTAMP_REGISTER, CTS, 0, 1)
142 REG32(WIR, 0x2c)
143     FIELD(WIR, EW, 8, 8)
144     FIELD(WIR, FW, 0, 8)
145 REG32(TXFIFO_ID, 0x30)
146     FIELD(TXFIFO_ID, IDH, 21, 11)
147     FIELD(TXFIFO_ID, SRRRTR, 20, 1)
148     FIELD(TXFIFO_ID, IDE, 19, 1)
149     FIELD(TXFIFO_ID, IDL, 1, 18)
150     FIELD(TXFIFO_ID, RTR, 0, 1)
151 REG32(TXFIFO_DLC, 0x34)
152     FIELD(TXFIFO_DLC, DLC, 28, 4)
153 REG32(TXFIFO_DATA1, 0x38)
154     FIELD(TXFIFO_DATA1, DB0, 24, 8)
155     FIELD(TXFIFO_DATA1, DB1, 16, 8)
156     FIELD(TXFIFO_DATA1, DB2, 8, 8)
157     FIELD(TXFIFO_DATA1, DB3, 0, 8)
158 REG32(TXFIFO_DATA2, 0x3c)
159     FIELD(TXFIFO_DATA2, DB4, 24, 8)
160     FIELD(TXFIFO_DATA2, DB5, 16, 8)
161     FIELD(TXFIFO_DATA2, DB6, 8, 8)
162     FIELD(TXFIFO_DATA2, DB7, 0, 8)
163 REG32(TXHPB_ID, 0x40)
164     FIELD(TXHPB_ID, IDH, 21, 11)
165     FIELD(TXHPB_ID, SRRRTR, 20, 1)
166     FIELD(TXHPB_ID, IDE, 19, 1)
167     FIELD(TXHPB_ID, IDL, 1, 18)
168     FIELD(TXHPB_ID, RTR, 0, 1)
169 REG32(TXHPB_DLC, 0x44)
170     FIELD(TXHPB_DLC, DLC, 28, 4)
171 REG32(TXHPB_DATA1, 0x48)
172     FIELD(TXHPB_DATA1, DB0, 24, 8)
173     FIELD(TXHPB_DATA1, DB1, 16, 8)
174     FIELD(TXHPB_DATA1, DB2, 8, 8)
175     FIELD(TXHPB_DATA1, DB3, 0, 8)
176 REG32(TXHPB_DATA2, 0x4c)
177     FIELD(TXHPB_DATA2, DB4, 24, 8)
178     FIELD(TXHPB_DATA2, DB5, 16, 8)
179     FIELD(TXHPB_DATA2, DB6, 8, 8)
180     FIELD(TXHPB_DATA2, DB7, 0, 8)
181 REG32(RXFIFO_ID, 0x50)
182     FIELD(RXFIFO_ID, IDH, 21, 11)
183     FIELD(RXFIFO_ID, SRRRTR, 20, 1)
184     FIELD(RXFIFO_ID, IDE, 19, 1)
185     FIELD(RXFIFO_ID, IDL, 1, 18)
186     FIELD(RXFIFO_ID, RTR, 0, 1)
187 REG32(RXFIFO_DLC, 0x54)
188     FIELD(RXFIFO_DLC, DLC, 28, 4)
189     FIELD(RXFIFO_DLC, RXT, 0, 16)
190 REG32(RXFIFO_DATA1, 0x58)
191     FIELD(RXFIFO_DATA1, DB0, 24, 8)
192     FIELD(RXFIFO_DATA1, DB1, 16, 8)
193     FIELD(RXFIFO_DATA1, DB2, 8, 8)
194     FIELD(RXFIFO_DATA1, DB3, 0, 8)
195 REG32(RXFIFO_DATA2, 0x5c)
196     FIELD(RXFIFO_DATA2, DB4, 24, 8)
197     FIELD(RXFIFO_DATA2, DB5, 16, 8)
198     FIELD(RXFIFO_DATA2, DB6, 8, 8)
199     FIELD(RXFIFO_DATA2, DB7, 0, 8)
200 REG32(AFR, 0x60)
201     FIELD(AFR, UAF4, 3, 1)
202     FIELD(AFR, UAF3, 2, 1)
203     FIELD(AFR, UAF2, 1, 1)
204     FIELD(AFR, UAF1, 0, 1)
205 REG32(AFMR1, 0x64)
206     FIELD(AFMR1, AMIDH, 21, 11)
207     FIELD(AFMR1, AMSRR, 20, 1)
208     FIELD(AFMR1, AMIDE, 19, 1)
209     FIELD(AFMR1, AMIDL, 1, 18)
210     FIELD(AFMR1, AMRTR, 0, 1)
211 REG32(AFIR1, 0x68)
212     FIELD(AFIR1, AIIDH, 21, 11)
213     FIELD(AFIR1, AISRR, 20, 1)
214     FIELD(AFIR1, AIIDE, 19, 1)
215     FIELD(AFIR1, AIIDL, 1, 18)
216     FIELD(AFIR1, AIRTR, 0, 1)
217 REG32(AFMR2, 0x6c)
218     FIELD(AFMR2, AMIDH, 21, 11)
219     FIELD(AFMR2, AMSRR, 20, 1)
220     FIELD(AFMR2, AMIDE, 19, 1)
221     FIELD(AFMR2, AMIDL, 1, 18)
222     FIELD(AFMR2, AMRTR, 0, 1)
223 REG32(AFIR2, 0x70)
224     FIELD(AFIR2, AIIDH, 21, 11)
225     FIELD(AFIR2, AISRR, 20, 1)
226     FIELD(AFIR2, AIIDE, 19, 1)
227     FIELD(AFIR2, AIIDL, 1, 18)
228     FIELD(AFIR2, AIRTR, 0, 1)
229 REG32(AFMR3, 0x74)
230     FIELD(AFMR3, AMIDH, 21, 11)
231     FIELD(AFMR3, AMSRR, 20, 1)
232     FIELD(AFMR3, AMIDE, 19, 1)
233     FIELD(AFMR3, AMIDL, 1, 18)
234     FIELD(AFMR3, AMRTR, 0, 1)
235 REG32(AFIR3, 0x78)
236     FIELD(AFIR3, AIIDH, 21, 11)
237     FIELD(AFIR3, AISRR, 20, 1)
238     FIELD(AFIR3, AIIDE, 19, 1)
239     FIELD(AFIR3, AIIDL, 1, 18)
240     FIELD(AFIR3, AIRTR, 0, 1)
241 REG32(AFMR4, 0x7c)
242     FIELD(AFMR4, AMIDH, 21, 11)
243     FIELD(AFMR4, AMSRR, 20, 1)
244     FIELD(AFMR4, AMIDE, 19, 1)
245     FIELD(AFMR4, AMIDL, 1, 18)
246     FIELD(AFMR4, AMRTR, 0, 1)
247 REG32(AFIR4, 0x80)
248     FIELD(AFIR4, AIIDH, 21, 11)
249     FIELD(AFIR4, AISRR, 20, 1)
250     FIELD(AFIR4, AIIDE, 19, 1)
251     FIELD(AFIR4, AIIDL, 1, 18)
252     FIELD(AFIR4, AIRTR, 0, 1)
253 
254 static void can_update_irq(XlnxZynqMPCANState *s)
255 {
256     uint32_t irq;
257 
258     /* Watermark register interrupts. */
259     if ((fifo32_num_free(&s->tx_fifo) / CAN_FRAME_SIZE) >
260             ARRAY_FIELD_EX32(s->regs, WIR, EW)) {
261         ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, TXFWMEMP, 1);
262     }
263 
264     if ((fifo32_num_used(&s->rx_fifo) / CAN_FRAME_SIZE) >
265             ARRAY_FIELD_EX32(s->regs, WIR, FW)) {
266         ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, RXFWMFLL, 1);
267     }
268 
269     /* RX Interrupts. */
270     if (fifo32_num_used(&s->rx_fifo) >= CAN_FRAME_SIZE) {
271         ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, RXNEMP, 1);
272     }
273 
274     /* TX interrupts. */
275     if (fifo32_is_empty(&s->tx_fifo)) {
276         ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, TXFEMP, 1);
277     }
278 
279     if (fifo32_is_full(&s->tx_fifo)) {
280         ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, TXFLL, 1);
281     }
282 
283     if (fifo32_is_full(&s->txhpb_fifo)) {
284         ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, TXBFLL, 1);
285     }
286 
287     irq = s->regs[R_INTERRUPT_STATUS_REGISTER];
288     irq &= s->regs[R_INTERRUPT_ENABLE_REGISTER];
289 
290     trace_xlnx_can_update_irq(s->regs[R_INTERRUPT_STATUS_REGISTER],
291                               s->regs[R_INTERRUPT_ENABLE_REGISTER], irq);
292     qemu_set_irq(s->irq, irq);
293 }
294 
295 static void can_ier_post_write(RegisterInfo *reg, uint64_t val)
296 {
297     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
298 
299     can_update_irq(s);
300 }
301 
302 static uint64_t can_icr_pre_write(RegisterInfo *reg, uint64_t val)
303 {
304     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
305 
306     s->regs[R_INTERRUPT_STATUS_REGISTER] &= ~val;
307     can_update_irq(s);
308 
309     return 0;
310 }
311 
312 static void can_config_reset(XlnxZynqMPCANState *s)
313 {
314     /* Reset all the configuration registers. */
315     register_reset(&s->reg_info[R_SOFTWARE_RESET_REGISTER]);
316     register_reset(&s->reg_info[R_MODE_SELECT_REGISTER]);
317     register_reset(
318               &s->reg_info[R_ARBITRATION_PHASE_BAUD_RATE_PRESCALER_REGISTER]);
319     register_reset(&s->reg_info[R_ARBITRATION_PHASE_BIT_TIMING_REGISTER]);
320     register_reset(&s->reg_info[R_STATUS_REGISTER]);
321     register_reset(&s->reg_info[R_INTERRUPT_STATUS_REGISTER]);
322     register_reset(&s->reg_info[R_INTERRUPT_ENABLE_REGISTER]);
323     register_reset(&s->reg_info[R_INTERRUPT_CLEAR_REGISTER]);
324     register_reset(&s->reg_info[R_WIR]);
325 }
326 
327 static void can_config_mode(XlnxZynqMPCANState *s)
328 {
329     register_reset(&s->reg_info[R_ERROR_COUNTER_REGISTER]);
330     register_reset(&s->reg_info[R_ERROR_STATUS_REGISTER]);
331 
332     /* Put XlnxZynqMPCAN in configuration mode. */
333     ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, CONFIG, 1);
334     ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, WKUP, 0);
335     ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, SLP, 0);
336     ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, BSOFF, 0);
337     ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, ERROR, 0);
338     ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, RXOFLW, 0);
339     ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, RXOK, 0);
340     ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, TXOK, 0);
341     ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, ARBLST, 0);
342 
343     can_update_irq(s);
344 }
345 
346 static void update_status_register_mode_bits(XlnxZynqMPCANState *s)
347 {
348     bool sleep_status = ARRAY_FIELD_EX32(s->regs, STATUS_REGISTER, SLEEP);
349     bool sleep_mode = ARRAY_FIELD_EX32(s->regs, MODE_SELECT_REGISTER, SLEEP);
350     /* Wake up interrupt bit. */
351     bool wakeup_irq_val = sleep_status && (sleep_mode == 0);
352     /* Sleep interrupt bit. */
353     bool sleep_irq_val = sleep_mode && (sleep_status == 0);
354 
355     /* Clear previous core mode status bits. */
356     ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, LBACK, 0);
357     ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, SLEEP, 0);
358     ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, SNOOP, 0);
359     ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, NORMAL, 0);
360 
361     /* set current mode bit and generate irqs accordingly. */
362     if (ARRAY_FIELD_EX32(s->regs, MODE_SELECT_REGISTER, LBACK)) {
363         ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, LBACK, 1);
364     } else if (ARRAY_FIELD_EX32(s->regs, MODE_SELECT_REGISTER, SLEEP)) {
365         ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, SLEEP, 1);
366         ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, SLP,
367                          sleep_irq_val);
368     } else if (ARRAY_FIELD_EX32(s->regs, MODE_SELECT_REGISTER, SNOOP)) {
369         ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, SNOOP, 1);
370     } else {
371         /*
372          * If all bits are zero then XlnxZynqMPCAN is set in normal mode.
373          */
374         ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, NORMAL, 1);
375         /* Set wakeup interrupt bit. */
376         ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, WKUP,
377                          wakeup_irq_val);
378     }
379 
380     can_update_irq(s);
381 }
382 
383 static void can_exit_sleep_mode(XlnxZynqMPCANState *s)
384 {
385     ARRAY_FIELD_DP32(s->regs, MODE_SELECT_REGISTER, SLEEP, 0);
386     update_status_register_mode_bits(s);
387 }
388 
389 static void generate_frame(qemu_can_frame *frame, uint32_t *data)
390 {
391     frame->can_id = data[0];
392     frame->can_dlc = FIELD_EX32(data[1], TXFIFO_DLC, DLC);
393 
394     frame->data[0] = FIELD_EX32(data[2], TXFIFO_DATA1, DB3);
395     frame->data[1] = FIELD_EX32(data[2], TXFIFO_DATA1, DB2);
396     frame->data[2] = FIELD_EX32(data[2], TXFIFO_DATA1, DB1);
397     frame->data[3] = FIELD_EX32(data[2], TXFIFO_DATA1, DB0);
398 
399     frame->data[4] = FIELD_EX32(data[3], TXFIFO_DATA2, DB7);
400     frame->data[5] = FIELD_EX32(data[3], TXFIFO_DATA2, DB6);
401     frame->data[6] = FIELD_EX32(data[3], TXFIFO_DATA2, DB5);
402     frame->data[7] = FIELD_EX32(data[3], TXFIFO_DATA2, DB4);
403 }
404 
405 static bool tx_ready_check(XlnxZynqMPCANState *s)
406 {
407     if (ARRAY_FIELD_EX32(s->regs, SOFTWARE_RESET_REGISTER, SRST)) {
408         g_autofree char *path = object_get_canonical_path(OBJECT(s));
409 
410         qemu_log_mask(LOG_GUEST_ERROR, "%s: Attempting to transfer data while"
411                       " data while controller is in reset mode.\n",
412                       path);
413         return false;
414     }
415 
416     if (ARRAY_FIELD_EX32(s->regs, SOFTWARE_RESET_REGISTER, CEN) == 0) {
417         g_autofree char *path = object_get_canonical_path(OBJECT(s));
418 
419         qemu_log_mask(LOG_GUEST_ERROR, "%s: Attempting to transfer"
420                       " data while controller is in configuration mode. Reset"
421                       " the core so operations can start fresh.\n",
422                       path);
423         return false;
424     }
425 
426     if (ARRAY_FIELD_EX32(s->regs, STATUS_REGISTER, SNOOP)) {
427         g_autofree char *path = object_get_canonical_path(OBJECT(s));
428 
429         qemu_log_mask(LOG_GUEST_ERROR, "%s: Attempting to transfer"
430                       " data while controller is in SNOOP MODE.\n",
431                       path);
432         return false;
433     }
434 
435     return true;
436 }
437 
438 static void transfer_fifo(XlnxZynqMPCANState *s, Fifo32 *fifo)
439 {
440     qemu_can_frame frame;
441     uint32_t data[CAN_FRAME_SIZE];
442     int i;
443     bool can_tx = tx_ready_check(s);
444 
445     if (!can_tx) {
446         g_autofree char *path = object_get_canonical_path(OBJECT(s));
447 
448         qemu_log_mask(LOG_GUEST_ERROR, "%s: Controller is not enabled for data"
449                       " transfer.\n", path);
450         can_update_irq(s);
451         return;
452     }
453 
454     while (!fifo32_is_empty(fifo)) {
455         for (i = 0; i < CAN_FRAME_SIZE; i++) {
456             data[i] = fifo32_pop(fifo);
457         }
458 
459         if (ARRAY_FIELD_EX32(s->regs, STATUS_REGISTER, LBACK)) {
460             /*
461              * Controller is in loopback. In Loopback mode, the CAN core
462              * transmits a recessive bitstream on to the XlnxZynqMPCAN Bus.
463              * Any message transmitted is looped back to the RX line and
464              * acknowledged. The XlnxZynqMPCAN core receives any message
465              * that it transmits.
466              */
467             if (fifo32_is_full(&s->rx_fifo)) {
468                 ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, RXOFLW, 1);
469             } else {
470                 for (i = 0; i < CAN_FRAME_SIZE; i++) {
471                     fifo32_push(&s->rx_fifo, data[i]);
472                 }
473 
474                 ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, RXOK, 1);
475             }
476         } else {
477             /* Normal mode Tx. */
478             generate_frame(&frame, data);
479 
480             trace_xlnx_can_tx_data(frame.can_id, frame.can_dlc,
481                                    frame.data[0], frame.data[1],
482                                    frame.data[2], frame.data[3],
483                                    frame.data[4], frame.data[5],
484                                    frame.data[6], frame.data[7]);
485             can_bus_client_send(&s->bus_client, &frame, 1);
486         }
487     }
488 
489     ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, TXOK, 1);
490     ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, TXBFLL, 0);
491 
492     if (ARRAY_FIELD_EX32(s->regs, STATUS_REGISTER, SLEEP)) {
493         can_exit_sleep_mode(s);
494     }
495 
496     can_update_irq(s);
497 }
498 
499 static uint64_t can_srr_pre_write(RegisterInfo *reg, uint64_t val)
500 {
501     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
502 
503     ARRAY_FIELD_DP32(s->regs, SOFTWARE_RESET_REGISTER, CEN,
504                      FIELD_EX32(val, SOFTWARE_RESET_REGISTER, CEN));
505 
506     if (FIELD_EX32(val, SOFTWARE_RESET_REGISTER, SRST)) {
507         trace_xlnx_can_reset(val);
508 
509         /* First, core will do software reset then will enter in config mode. */
510         can_config_reset(s);
511     }
512 
513     if (ARRAY_FIELD_EX32(s->regs, SOFTWARE_RESET_REGISTER, CEN) == 0) {
514         can_config_mode(s);
515     } else {
516         /*
517          * Leave config mode. Now XlnxZynqMPCAN core will enter normal,
518          * sleep, snoop or loopback mode depending upon LBACK, SLEEP, SNOOP
519          * register states.
520          */
521         ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, CONFIG, 0);
522 
523         ptimer_transaction_begin(s->can_timer);
524         ptimer_set_count(s->can_timer, 0);
525         ptimer_transaction_commit(s->can_timer);
526 
527         /* XlnxZynqMPCAN is out of config mode. It will send pending data. */
528         transfer_fifo(s, &s->txhpb_fifo);
529         transfer_fifo(s, &s->tx_fifo);
530     }
531 
532     update_status_register_mode_bits(s);
533 
534     return s->regs[R_SOFTWARE_RESET_REGISTER];
535 }
536 
537 static uint64_t can_msr_pre_write(RegisterInfo *reg, uint64_t val)
538 {
539     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
540     uint8_t multi_mode;
541 
542     /*
543      * Multiple mode set check. This is done to make sure user doesn't set
544      * multiple modes.
545      */
546     multi_mode = FIELD_EX32(val, MODE_SELECT_REGISTER, LBACK) +
547                  FIELD_EX32(val, MODE_SELECT_REGISTER, SLEEP) +
548                  FIELD_EX32(val, MODE_SELECT_REGISTER, SNOOP);
549 
550     if (multi_mode > 1) {
551         g_autofree char *path = object_get_canonical_path(OBJECT(s));
552 
553         qemu_log_mask(LOG_GUEST_ERROR, "%s: Attempting to config"
554                       " several modes simultaneously. One mode will be selected"
555                       " according to their priority: LBACK > SLEEP > SNOOP.\n",
556                       path);
557     }
558 
559     if (ARRAY_FIELD_EX32(s->regs, SOFTWARE_RESET_REGISTER, CEN) == 0) {
560         /* We are in configuration mode, any mode can be selected. */
561         s->regs[R_MODE_SELECT_REGISTER] = val;
562     } else {
563         bool sleep_mode_bit = FIELD_EX32(val, MODE_SELECT_REGISTER, SLEEP);
564 
565         ARRAY_FIELD_DP32(s->regs, MODE_SELECT_REGISTER, SLEEP, sleep_mode_bit);
566 
567         if (FIELD_EX32(val, MODE_SELECT_REGISTER, LBACK)) {
568             g_autofree char *path = object_get_canonical_path(OBJECT(s));
569 
570             qemu_log_mask(LOG_GUEST_ERROR, "%s: Attempting to set"
571                           " LBACK mode without setting CEN bit as 0.\n",
572                           path);
573         } else if (FIELD_EX32(val, MODE_SELECT_REGISTER, SNOOP)) {
574             g_autofree char *path = object_get_canonical_path(OBJECT(s));
575 
576             qemu_log_mask(LOG_GUEST_ERROR, "%s: Attempting to set"
577                           " SNOOP mode without setting CEN bit as 0.\n",
578                           path);
579         }
580 
581         update_status_register_mode_bits(s);
582     }
583 
584     return s->regs[R_MODE_SELECT_REGISTER];
585 }
586 
587 static uint64_t can_brpr_pre_write(RegisterInfo  *reg, uint64_t val)
588 {
589     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
590 
591     /* Only allow writes when in config mode. */
592     if (ARRAY_FIELD_EX32(s->regs, SOFTWARE_RESET_REGISTER, CEN)) {
593         return s->regs[R_ARBITRATION_PHASE_BAUD_RATE_PRESCALER_REGISTER];
594     }
595 
596     return val;
597 }
598 
599 static uint64_t can_btr_pre_write(RegisterInfo  *reg, uint64_t val)
600 {
601     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
602 
603     /* Only allow writes when in config mode. */
604     if (ARRAY_FIELD_EX32(s->regs, SOFTWARE_RESET_REGISTER, CEN)) {
605         return s->regs[R_ARBITRATION_PHASE_BIT_TIMING_REGISTER];
606     }
607 
608     return val;
609 }
610 
611 static uint64_t can_tcr_pre_write(RegisterInfo  *reg, uint64_t val)
612 {
613     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
614 
615     if (FIELD_EX32(val, TIMESTAMP_REGISTER, CTS)) {
616         ptimer_transaction_begin(s->can_timer);
617         ptimer_set_count(s->can_timer, 0);
618         ptimer_transaction_commit(s->can_timer);
619     }
620 
621     return 0;
622 }
623 
624 static void update_rx_fifo(XlnxZynqMPCANState *s, const qemu_can_frame *frame)
625 {
626     bool filter_pass = false;
627     uint16_t timestamp = 0;
628 
629     /* If no filter is enabled. Message will be stored in FIFO. */
630     if (!((ARRAY_FIELD_EX32(s->regs, AFR, UAF1)) |
631        (ARRAY_FIELD_EX32(s->regs, AFR, UAF2)) |
632        (ARRAY_FIELD_EX32(s->regs, AFR, UAF3)) |
633        (ARRAY_FIELD_EX32(s->regs, AFR, UAF4)))) {
634         filter_pass = true;
635     }
636 
637     /*
638      * Messages that pass any of the acceptance filters will be stored in
639      * the RX FIFO.
640      */
641     if (ARRAY_FIELD_EX32(s->regs, AFR, UAF1)) {
642         uint32_t id_masked = s->regs[R_AFMR1] & frame->can_id;
643         uint32_t filter_id_masked = s->regs[R_AFMR1] & s->regs[R_AFIR1];
644 
645         if (filter_id_masked == id_masked) {
646             filter_pass = true;
647         }
648     }
649 
650     if (ARRAY_FIELD_EX32(s->regs, AFR, UAF2)) {
651         uint32_t id_masked = s->regs[R_AFMR2] & frame->can_id;
652         uint32_t filter_id_masked = s->regs[R_AFMR2] & s->regs[R_AFIR2];
653 
654         if (filter_id_masked == id_masked) {
655             filter_pass = true;
656         }
657     }
658 
659     if (ARRAY_FIELD_EX32(s->regs, AFR, UAF3)) {
660         uint32_t id_masked = s->regs[R_AFMR3] & frame->can_id;
661         uint32_t filter_id_masked = s->regs[R_AFMR3] & s->regs[R_AFIR3];
662 
663         if (filter_id_masked == id_masked) {
664             filter_pass = true;
665         }
666     }
667 
668     if (ARRAY_FIELD_EX32(s->regs, AFR, UAF4)) {
669         uint32_t id_masked = s->regs[R_AFMR4] & frame->can_id;
670         uint32_t filter_id_masked = s->regs[R_AFMR4] & s->regs[R_AFIR4];
671 
672         if (filter_id_masked == id_masked) {
673             filter_pass = true;
674         }
675     }
676 
677     if (!filter_pass) {
678         trace_xlnx_can_rx_fifo_filter_reject(frame->can_id, frame->can_dlc);
679         return;
680     }
681 
682     /* Store the message in fifo if it passed through any of the filters. */
683     if (filter_pass && frame->can_dlc <= MAX_DLC) {
684 
685         if (fifo32_is_full(&s->rx_fifo)) {
686             ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, RXOFLW, 1);
687         } else {
688             timestamp = CAN_TIMER_MAX - ptimer_get_count(s->can_timer);
689 
690             fifo32_push(&s->rx_fifo, frame->can_id);
691 
692             fifo32_push(&s->rx_fifo, deposit32(0, R_RXFIFO_DLC_DLC_SHIFT,
693                                                R_RXFIFO_DLC_DLC_LENGTH,
694                                                frame->can_dlc) |
695                                      deposit32(0, R_RXFIFO_DLC_RXT_SHIFT,
696                                                R_RXFIFO_DLC_RXT_LENGTH,
697                                                timestamp));
698 
699             /* First 32 bit of the data. */
700             fifo32_push(&s->rx_fifo, deposit32(0, R_TXFIFO_DATA1_DB3_SHIFT,
701                                                R_TXFIFO_DATA1_DB3_LENGTH,
702                                                frame->data[0]) |
703                                      deposit32(0, R_TXFIFO_DATA1_DB2_SHIFT,
704                                                R_TXFIFO_DATA1_DB2_LENGTH,
705                                                frame->data[1]) |
706                                      deposit32(0, R_TXFIFO_DATA1_DB1_SHIFT,
707                                                R_TXFIFO_DATA1_DB1_LENGTH,
708                                                frame->data[2]) |
709                                      deposit32(0, R_TXFIFO_DATA1_DB0_SHIFT,
710                                                R_TXFIFO_DATA1_DB0_LENGTH,
711                                                frame->data[3]));
712             /* Last 32 bit of the data. */
713             fifo32_push(&s->rx_fifo, deposit32(0, R_TXFIFO_DATA2_DB7_SHIFT,
714                                                R_TXFIFO_DATA2_DB7_LENGTH,
715                                                frame->data[4]) |
716                                      deposit32(0, R_TXFIFO_DATA2_DB6_SHIFT,
717                                                R_TXFIFO_DATA2_DB6_LENGTH,
718                                                frame->data[5]) |
719                                      deposit32(0, R_TXFIFO_DATA2_DB5_SHIFT,
720                                                R_TXFIFO_DATA2_DB5_LENGTH,
721                                                frame->data[6]) |
722                                      deposit32(0, R_TXFIFO_DATA2_DB4_SHIFT,
723                                                R_TXFIFO_DATA2_DB4_LENGTH,
724                                                frame->data[7]));
725 
726             ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, RXOK, 1);
727             trace_xlnx_can_rx_data(frame->can_id, frame->can_dlc,
728                                    frame->data[0], frame->data[1],
729                                    frame->data[2], frame->data[3],
730                                    frame->data[4], frame->data[5],
731                                    frame->data[6], frame->data[7]);
732         }
733 
734         can_update_irq(s);
735     }
736 }
737 
738 static uint64_t can_rxfifo_pre_read(RegisterInfo *reg, uint64_t val)
739 {
740     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
741 
742     if (!fifo32_is_empty(&s->rx_fifo)) {
743         val = fifo32_pop(&s->rx_fifo);
744     } else {
745         ARRAY_FIELD_DP32(s->regs, INTERRUPT_STATUS_REGISTER, RXUFLW, 1);
746     }
747 
748     can_update_irq(s);
749     return val;
750 }
751 
752 static void can_filter_enable_post_write(RegisterInfo *reg, uint64_t val)
753 {
754     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
755 
756     if (ARRAY_FIELD_EX32(s->regs, AFR, UAF1) &&
757         ARRAY_FIELD_EX32(s->regs, AFR, UAF2) &&
758         ARRAY_FIELD_EX32(s->regs, AFR, UAF3) &&
759         ARRAY_FIELD_EX32(s->regs, AFR, UAF4)) {
760         ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, ACFBSY, 1);
761     } else {
762         ARRAY_FIELD_DP32(s->regs, STATUS_REGISTER, ACFBSY, 0);
763     }
764 }
765 
766 static uint64_t can_filter_mask_pre_write(RegisterInfo *reg, uint64_t val)
767 {
768     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
769     uint32_t reg_idx = (reg->access->addr) / 4;
770     uint32_t filter_number = (reg_idx - R_AFMR1) / 2;
771 
772     /* modify an acceptance filter, the corresponding UAF bit should be '0'. */
773     if (!(s->regs[R_AFR] & (1 << filter_number))) {
774         s->regs[reg_idx] = val;
775 
776         trace_xlnx_can_filter_mask_pre_write(filter_number, s->regs[reg_idx]);
777     } else {
778         g_autofree char *path = object_get_canonical_path(OBJECT(s));
779 
780         qemu_log_mask(LOG_GUEST_ERROR, "%s: Acceptance filter %d"
781                       " mask is not set as corresponding UAF bit is not 0.\n",
782                       path, filter_number + 1);
783     }
784 
785     return s->regs[reg_idx];
786 }
787 
788 static uint64_t can_filter_id_pre_write(RegisterInfo *reg, uint64_t val)
789 {
790     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
791     uint32_t reg_idx = (reg->access->addr) / 4;
792     uint32_t filter_number = (reg_idx - R_AFIR1) / 2;
793 
794     if (!(s->regs[R_AFR] & (1 << filter_number))) {
795         s->regs[reg_idx] = val;
796 
797         trace_xlnx_can_filter_id_pre_write(filter_number, s->regs[reg_idx]);
798     } else {
799         g_autofree char *path = object_get_canonical_path(OBJECT(s));
800 
801         qemu_log_mask(LOG_GUEST_ERROR, "%s: Acceptance filter %d"
802                       " id is not set as corresponding UAF bit is not 0.\n",
803                       path, filter_number + 1);
804     }
805 
806     return s->regs[reg_idx];
807 }
808 
809 static void can_tx_post_write(RegisterInfo *reg, uint64_t val)
810 {
811     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(reg->opaque);
812 
813     bool is_txhpb = reg->access->addr > A_TXFIFO_DATA2;
814 
815     bool initiate_transfer = (reg->access->addr == A_TXFIFO_DATA2) ||
816                              (reg->access->addr == A_TXHPB_DATA2);
817 
818     Fifo32 *f = is_txhpb ? &s->txhpb_fifo : &s->tx_fifo;
819 
820     if (!fifo32_is_full(f)) {
821         fifo32_push(f, val);
822     } else {
823         g_autofree char *path = object_get_canonical_path(OBJECT(s));
824 
825         qemu_log_mask(LOG_GUEST_ERROR, "%s: TX FIFO is full.\n", path);
826     }
827 
828     /* Initiate the message send if TX register is written. */
829     if (initiate_transfer &&
830         ARRAY_FIELD_EX32(s->regs, SOFTWARE_RESET_REGISTER, CEN)) {
831         transfer_fifo(s, f);
832     }
833 
834     can_update_irq(s);
835 }
836 
837 static const RegisterAccessInfo can_regs_info[] = {
838     {   .name = "SOFTWARE_RESET_REGISTER",
839         .addr = A_SOFTWARE_RESET_REGISTER,
840         .rsvd = 0xfffffffc,
841         .pre_write = can_srr_pre_write,
842     },{ .name = "MODE_SELECT_REGISTER",
843         .addr = A_MODE_SELECT_REGISTER,
844         .rsvd = 0xfffffff8,
845         .pre_write = can_msr_pre_write,
846     },{ .name = "ARBITRATION_PHASE_BAUD_RATE_PRESCALER_REGISTER",
847         .addr = A_ARBITRATION_PHASE_BAUD_RATE_PRESCALER_REGISTER,
848         .rsvd = 0xffffff00,
849         .pre_write = can_brpr_pre_write,
850     },{ .name = "ARBITRATION_PHASE_BIT_TIMING_REGISTER",
851         .addr = A_ARBITRATION_PHASE_BIT_TIMING_REGISTER,
852         .rsvd = 0xfffffe00,
853         .pre_write = can_btr_pre_write,
854     },{ .name = "ERROR_COUNTER_REGISTER",
855         .addr = A_ERROR_COUNTER_REGISTER,
856         .rsvd = 0xffff0000,
857         .ro = 0xffffffff,
858     },{ .name = "ERROR_STATUS_REGISTER",
859         .addr = A_ERROR_STATUS_REGISTER,
860         .rsvd = 0xffffffe0,
861         .w1c = 0x1f,
862     },{ .name = "STATUS_REGISTER",  .addr = A_STATUS_REGISTER,
863         .reset = 0x1,
864         .rsvd = 0xffffe000,
865         .ro = 0x1fff,
866     },{ .name = "INTERRUPT_STATUS_REGISTER",
867         .addr = A_INTERRUPT_STATUS_REGISTER,
868         .reset = 0x6000,
869         .rsvd = 0xffff8000,
870         .ro = 0x7fff,
871     },{ .name = "INTERRUPT_ENABLE_REGISTER",
872         .addr = A_INTERRUPT_ENABLE_REGISTER,
873         .rsvd = 0xffff8000,
874         .post_write = can_ier_post_write,
875     },{ .name = "INTERRUPT_CLEAR_REGISTER",
876         .addr = A_INTERRUPT_CLEAR_REGISTER,
877         .rsvd = 0xffff8000,
878         .pre_write = can_icr_pre_write,
879     },{ .name = "TIMESTAMP_REGISTER",
880         .addr = A_TIMESTAMP_REGISTER,
881         .rsvd = 0xfffffffe,
882         .pre_write = can_tcr_pre_write,
883     },{ .name = "WIR",  .addr = A_WIR,
884         .reset = 0x3f3f,
885         .rsvd = 0xffff0000,
886     },{ .name = "TXFIFO_ID",  .addr = A_TXFIFO_ID,
887         .post_write = can_tx_post_write,
888     },{ .name = "TXFIFO_DLC",  .addr = A_TXFIFO_DLC,
889         .rsvd = 0xfffffff,
890         .post_write = can_tx_post_write,
891     },{ .name = "TXFIFO_DATA1",  .addr = A_TXFIFO_DATA1,
892         .post_write = can_tx_post_write,
893     },{ .name = "TXFIFO_DATA2",  .addr = A_TXFIFO_DATA2,
894         .post_write = can_tx_post_write,
895     },{ .name = "TXHPB_ID",  .addr = A_TXHPB_ID,
896         .post_write = can_tx_post_write,
897     },{ .name = "TXHPB_DLC",  .addr = A_TXHPB_DLC,
898         .rsvd = 0xfffffff,
899         .post_write = can_tx_post_write,
900     },{ .name = "TXHPB_DATA1",  .addr = A_TXHPB_DATA1,
901         .post_write = can_tx_post_write,
902     },{ .name = "TXHPB_DATA2",  .addr = A_TXHPB_DATA2,
903         .post_write = can_tx_post_write,
904     },{ .name = "RXFIFO_ID",  .addr = A_RXFIFO_ID,
905         .ro = 0xffffffff,
906         .post_read = can_rxfifo_pre_read,
907     },{ .name = "RXFIFO_DLC",  .addr = A_RXFIFO_DLC,
908         .rsvd = 0xfff0000,
909         .post_read = can_rxfifo_pre_read,
910     },{ .name = "RXFIFO_DATA1",  .addr = A_RXFIFO_DATA1,
911         .post_read = can_rxfifo_pre_read,
912     },{ .name = "RXFIFO_DATA2",  .addr = A_RXFIFO_DATA2,
913         .post_read = can_rxfifo_pre_read,
914     },{ .name = "AFR",  .addr = A_AFR,
915         .rsvd = 0xfffffff0,
916         .post_write = can_filter_enable_post_write,
917     },{ .name = "AFMR1",  .addr = A_AFMR1,
918         .pre_write = can_filter_mask_pre_write,
919     },{ .name = "AFIR1",  .addr = A_AFIR1,
920         .pre_write = can_filter_id_pre_write,
921     },{ .name = "AFMR2",  .addr = A_AFMR2,
922         .pre_write = can_filter_mask_pre_write,
923     },{ .name = "AFIR2",  .addr = A_AFIR2,
924         .pre_write = can_filter_id_pre_write,
925     },{ .name = "AFMR3",  .addr = A_AFMR3,
926         .pre_write = can_filter_mask_pre_write,
927     },{ .name = "AFIR3",  .addr = A_AFIR3,
928         .pre_write = can_filter_id_pre_write,
929     },{ .name = "AFMR4",  .addr = A_AFMR4,
930         .pre_write = can_filter_mask_pre_write,
931     },{ .name = "AFIR4",  .addr = A_AFIR4,
932         .pre_write = can_filter_id_pre_write,
933     }
934 };
935 
936 static void xlnx_zynqmp_can_ptimer_cb(void *opaque)
937 {
938     /* No action required on the timer rollover. */
939 }
940 
941 static const MemoryRegionOps can_ops = {
942     .read = register_read_memory,
943     .write = register_write_memory,
944     .endianness = DEVICE_LITTLE_ENDIAN,
945     .valid = {
946         .min_access_size = 4,
947         .max_access_size = 4,
948     },
949 };
950 
951 static void xlnx_zynqmp_can_reset_init(Object *obj, ResetType type)
952 {
953     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(obj);
954     unsigned int i;
955 
956     for (i = R_RXFIFO_ID; i < ARRAY_SIZE(s->reg_info); ++i) {
957         register_reset(&s->reg_info[i]);
958     }
959 
960     ptimer_transaction_begin(s->can_timer);
961     ptimer_set_count(s->can_timer, 0);
962     ptimer_transaction_commit(s->can_timer);
963 }
964 
965 static void xlnx_zynqmp_can_reset_hold(Object *obj)
966 {
967     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(obj);
968     unsigned int i;
969 
970     for (i = 0; i < R_RXFIFO_ID; ++i) {
971         register_reset(&s->reg_info[i]);
972     }
973 
974     /*
975      * Reset FIFOs when CAN model is reset. This will clear the fifo writes
976      * done by post_write which gets called from register_reset function,
977      * post_write handle will not be able to trigger tx because CAN will be
978      * disabled when software_reset_register is cleared first.
979      */
980     fifo32_reset(&s->rx_fifo);
981     fifo32_reset(&s->tx_fifo);
982     fifo32_reset(&s->txhpb_fifo);
983 }
984 
985 static bool xlnx_zynqmp_can_can_receive(CanBusClientState *client)
986 {
987     XlnxZynqMPCANState *s = container_of(client, XlnxZynqMPCANState,
988                                          bus_client);
989 
990     if (ARRAY_FIELD_EX32(s->regs, SOFTWARE_RESET_REGISTER, SRST)) {
991         g_autofree char *path = object_get_canonical_path(OBJECT(s));
992 
993         qemu_log_mask(LOG_GUEST_ERROR, "%s: Controller is in reset state.\n",
994                       path);
995         return false;
996     }
997 
998     if ((ARRAY_FIELD_EX32(s->regs, SOFTWARE_RESET_REGISTER, CEN)) == 0) {
999         g_autofree char *path = object_get_canonical_path(OBJECT(s));
1000 
1001         qemu_log_mask(LOG_GUEST_ERROR, "%s: Controller is disabled. Incoming"
1002                       " messages will be discarded.\n", path);
1003         return false;
1004     }
1005 
1006     return true;
1007 }
1008 
1009 static ssize_t xlnx_zynqmp_can_receive(CanBusClientState *client,
1010                                const qemu_can_frame *buf, size_t buf_size) {
1011     XlnxZynqMPCANState *s = container_of(client, XlnxZynqMPCANState,
1012                                          bus_client);
1013     const qemu_can_frame *frame = buf;
1014 
1015     if (buf_size <= 0) {
1016         g_autofree char *path = object_get_canonical_path(OBJECT(s));
1017 
1018         qemu_log_mask(LOG_GUEST_ERROR, "%s: Error in the data received.\n",
1019                       path);
1020         return 0;
1021     }
1022 
1023     if (ARRAY_FIELD_EX32(s->regs, STATUS_REGISTER, SNOOP)) {
1024         /* Snoop Mode: Just keep the data. no response back. */
1025         update_rx_fifo(s, frame);
1026     } else if ((ARRAY_FIELD_EX32(s->regs, STATUS_REGISTER, SLEEP))) {
1027         /*
1028          * XlnxZynqMPCAN is in sleep mode. Any data on bus will bring it to wake
1029          * up state.
1030          */
1031         can_exit_sleep_mode(s);
1032         update_rx_fifo(s, frame);
1033     } else if ((ARRAY_FIELD_EX32(s->regs, STATUS_REGISTER, SLEEP)) == 0) {
1034         update_rx_fifo(s, frame);
1035     } else {
1036         /*
1037          * XlnxZynqMPCAN will not participate in normal bus communication
1038          * and will not receive any messages transmitted by other CAN nodes.
1039          */
1040         trace_xlnx_can_rx_discard(s->regs[R_STATUS_REGISTER]);
1041     }
1042 
1043     return 1;
1044 }
1045 
1046 static CanBusClientInfo can_xilinx_bus_client_info = {
1047     .can_receive = xlnx_zynqmp_can_can_receive,
1048     .receive = xlnx_zynqmp_can_receive,
1049 };
1050 
1051 static int xlnx_zynqmp_can_connect_to_bus(XlnxZynqMPCANState *s,
1052                                           CanBusState *bus)
1053 {
1054     s->bus_client.info = &can_xilinx_bus_client_info;
1055 
1056     if (can_bus_insert_client(bus, &s->bus_client) < 0) {
1057         return -1;
1058     }
1059     return 0;
1060 }
1061 
1062 static void xlnx_zynqmp_can_realize(DeviceState *dev, Error **errp)
1063 {
1064     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(dev);
1065 
1066     if (s->canbus) {
1067         if (xlnx_zynqmp_can_connect_to_bus(s, s->canbus) < 0) {
1068             g_autofree char *path = object_get_canonical_path(OBJECT(s));
1069 
1070             error_setg(errp, "%s: xlnx_zynqmp_can_connect_to_bus"
1071                        " failed.", path);
1072             return;
1073         }
1074     }
1075 
1076     /* Create RX FIFO, TXFIFO, TXHPB storage. */
1077     fifo32_create(&s->rx_fifo, RXFIFO_SIZE);
1078     fifo32_create(&s->tx_fifo, RXFIFO_SIZE);
1079     fifo32_create(&s->txhpb_fifo, CAN_FRAME_SIZE);
1080 
1081     /* Allocate a new timer. */
1082     s->can_timer = ptimer_init(xlnx_zynqmp_can_ptimer_cb, s,
1083                                PTIMER_POLICY_DEFAULT);
1084 
1085     ptimer_transaction_begin(s->can_timer);
1086 
1087     ptimer_set_freq(s->can_timer, s->cfg.ext_clk_freq);
1088     ptimer_set_limit(s->can_timer, CAN_TIMER_MAX, 1);
1089     ptimer_run(s->can_timer, 0);
1090     ptimer_transaction_commit(s->can_timer);
1091 }
1092 
1093 static void xlnx_zynqmp_can_init(Object *obj)
1094 {
1095     XlnxZynqMPCANState *s = XLNX_ZYNQMP_CAN(obj);
1096     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
1097 
1098     RegisterInfoArray *reg_array;
1099 
1100     memory_region_init(&s->iomem, obj, TYPE_XLNX_ZYNQMP_CAN,
1101                         XLNX_ZYNQMP_CAN_R_MAX * 4);
1102     reg_array = register_init_block32(DEVICE(obj), can_regs_info,
1103                                ARRAY_SIZE(can_regs_info),
1104                                s->reg_info, s->regs,
1105                                &can_ops,
1106                                XLNX_ZYNQMP_CAN_ERR_DEBUG,
1107                                XLNX_ZYNQMP_CAN_R_MAX * 4);
1108 
1109     memory_region_add_subregion(&s->iomem, 0x00, &reg_array->mem);
1110     sysbus_init_mmio(sbd, &s->iomem);
1111     sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->irq);
1112 }
1113 
1114 static const VMStateDescription vmstate_can = {
1115     .name = TYPE_XLNX_ZYNQMP_CAN,
1116     .version_id = 1,
1117     .minimum_version_id = 1,
1118     .fields = (VMStateField[]) {
1119         VMSTATE_FIFO32(rx_fifo, XlnxZynqMPCANState),
1120         VMSTATE_FIFO32(tx_fifo, XlnxZynqMPCANState),
1121         VMSTATE_FIFO32(txhpb_fifo, XlnxZynqMPCANState),
1122         VMSTATE_UINT32_ARRAY(regs, XlnxZynqMPCANState, XLNX_ZYNQMP_CAN_R_MAX),
1123         VMSTATE_PTIMER(can_timer, XlnxZynqMPCANState),
1124         VMSTATE_END_OF_LIST(),
1125     }
1126 };
1127 
1128 static Property xlnx_zynqmp_can_properties[] = {
1129     DEFINE_PROP_UINT32("ext_clk_freq", XlnxZynqMPCANState, cfg.ext_clk_freq,
1130                        CAN_DEFAULT_CLOCK),
1131     DEFINE_PROP_LINK("canbus", XlnxZynqMPCANState, canbus, TYPE_CAN_BUS,
1132                      CanBusState *),
1133     DEFINE_PROP_END_OF_LIST(),
1134 };
1135 
1136 static void xlnx_zynqmp_can_class_init(ObjectClass *klass, void *data)
1137 {
1138     DeviceClass *dc = DEVICE_CLASS(klass);
1139     ResettableClass *rc = RESETTABLE_CLASS(klass);
1140 
1141     rc->phases.enter = xlnx_zynqmp_can_reset_init;
1142     rc->phases.hold = xlnx_zynqmp_can_reset_hold;
1143     dc->realize = xlnx_zynqmp_can_realize;
1144     device_class_set_props(dc, xlnx_zynqmp_can_properties);
1145     dc->vmsd = &vmstate_can;
1146 }
1147 
1148 static const TypeInfo can_info = {
1149     .name          = TYPE_XLNX_ZYNQMP_CAN,
1150     .parent        = TYPE_SYS_BUS_DEVICE,
1151     .instance_size = sizeof(XlnxZynqMPCANState),
1152     .class_init    = xlnx_zynqmp_can_class_init,
1153     .instance_init = xlnx_zynqmp_can_init,
1154 };
1155 
1156 static void can_register_types(void)
1157 {
1158     type_register_static(&can_info);
1159 }
1160 
1161 type_init(can_register_types)
1162