xref: /openbmc/qemu/hw/ssi/ibex_spi_host.c (revision ce799a04)
1 /*
2  * QEMU model of the Ibex SPI Controller
3  * SPEC Reference: https://docs.opentitan.org/hw/ip/spi_host/doc/
4  *
5  * Copyright (C) 2022 Western Digital
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a copy
8  * of this software and associated documentation files (the "Software"), to deal
9  * in the Software without restriction, including without limitation the rights
10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11  * copies of the Software, and to permit persons to whom the Software is
12  * furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in
15  * all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23  * THE SOFTWARE.
24  */
25 
26 #include "qemu/osdep.h"
27 #include "qemu/log.h"
28 #include "qemu/module.h"
29 #include "hw/registerfields.h"
30 #include "hw/ssi/ibex_spi_host.h"
31 #include "hw/irq.h"
32 #include "hw/qdev-properties.h"
33 #include "hw/qdev-properties-system.h"
34 #include "migration/vmstate.h"
35 #include "trace.h"
36 
37 REG32(INTR_STATE, 0x00)
38     FIELD(INTR_STATE, ERROR, 0, 1)
39     FIELD(INTR_STATE, SPI_EVENT, 1, 1)
40 REG32(INTR_ENABLE, 0x04)
41     FIELD(INTR_ENABLE, ERROR, 0, 1)
42     FIELD(INTR_ENABLE, SPI_EVENT, 1, 1)
43 REG32(INTR_TEST, 0x08)
44     FIELD(INTR_TEST, ERROR, 0, 1)
45     FIELD(INTR_TEST, SPI_EVENT, 1, 1)
46 REG32(ALERT_TEST, 0x0c)
47     FIELD(ALERT_TEST, FETAL_TEST, 0, 1)
48 REG32(CONTROL, 0x10)
49     FIELD(CONTROL, RX_WATERMARK, 0, 8)
50     FIELD(CONTROL, TX_WATERMARK, 1, 8)
51     FIELD(CONTROL, OUTPUT_EN, 29, 1)
52     FIELD(CONTROL, SW_RST, 30, 1)
53     FIELD(CONTROL, SPIEN, 31, 1)
54 REG32(STATUS, 0x14)
55     FIELD(STATUS, TXQD, 0, 8)
56     FIELD(STATUS, RXQD, 18, 8)
57     FIELD(STATUS, CMDQD, 16, 3)
58     FIELD(STATUS, RXWM, 20, 1)
59     FIELD(STATUS, BYTEORDER, 22, 1)
60     FIELD(STATUS, RXSTALL, 23, 1)
61     FIELD(STATUS, RXEMPTY, 24, 1)
62     FIELD(STATUS, RXFULL, 25, 1)
63     FIELD(STATUS, TXWM, 26, 1)
64     FIELD(STATUS, TXSTALL, 27, 1)
65     FIELD(STATUS, TXEMPTY, 28, 1)
66     FIELD(STATUS, TXFULL, 29, 1)
67     FIELD(STATUS, ACTIVE, 30, 1)
68     FIELD(STATUS, READY, 31, 1)
69 REG32(CONFIGOPTS, 0x18)
70     FIELD(CONFIGOPTS, CLKDIV_0, 0, 16)
71     FIELD(CONFIGOPTS, CSNIDLE_0, 16, 4)
72     FIELD(CONFIGOPTS, CSNTRAIL_0, 20, 4)
73     FIELD(CONFIGOPTS, CSNLEAD_0, 24, 4)
74     FIELD(CONFIGOPTS, FULLCYC_0, 29, 1)
75     FIELD(CONFIGOPTS, CPHA_0, 30, 1)
76     FIELD(CONFIGOPTS, CPOL_0, 31, 1)
77 REG32(CSID, 0x1c)
78     FIELD(CSID, CSID, 0, 32)
79 REG32(COMMAND, 0x20)
80     FIELD(COMMAND, LEN, 0, 8)
81     FIELD(COMMAND, CSAAT, 9, 1)
82     FIELD(COMMAND, SPEED, 10, 2)
83     FIELD(COMMAND, DIRECTION, 12, 2)
84 REG32(ERROR_ENABLE, 0x2c)
85     FIELD(ERROR_ENABLE, CMDBUSY, 0, 1)
86     FIELD(ERROR_ENABLE, OVERFLOW, 1, 1)
87     FIELD(ERROR_ENABLE, UNDERFLOW, 2, 1)
88     FIELD(ERROR_ENABLE, CMDINVAL, 3, 1)
89     FIELD(ERROR_ENABLE, CSIDINVAL, 4, 1)
90 REG32(ERROR_STATUS, 0x30)
91     FIELD(ERROR_STATUS, CMDBUSY, 0, 1)
92     FIELD(ERROR_STATUS, OVERFLOW, 1, 1)
93     FIELD(ERROR_STATUS, UNDERFLOW, 2, 1)
94     FIELD(ERROR_STATUS, CMDINVAL, 3, 1)
95     FIELD(ERROR_STATUS, CSIDINVAL, 4, 1)
96     FIELD(ERROR_STATUS, ACCESSINVAL, 5, 1)
97 REG32(EVENT_ENABLE, 0x34)
98     FIELD(EVENT_ENABLE, RXFULL, 0, 1)
99     FIELD(EVENT_ENABLE, TXEMPTY, 1, 1)
100     FIELD(EVENT_ENABLE, RXWM, 2, 1)
101     FIELD(EVENT_ENABLE, TXWM, 3, 1)
102     FIELD(EVENT_ENABLE, READY, 4, 1)
103     FIELD(EVENT_ENABLE, IDLE, 5, 1)
104 
105 static inline uint8_t div4_round_up(uint8_t dividend)
106 {
107     return (dividend + 3) / 4;
108 }
109 
110 static void ibex_spi_rxfifo_reset(IbexSPIHostState *s)
111 {
112     uint32_t data = s->regs[IBEX_SPI_HOST_STATUS];
113     /* Empty the RX FIFO and assert RXEMPTY */
114     fifo8_reset(&s->rx_fifo);
115     data = FIELD_DP32(data, STATUS, RXFULL, 0);
116     data = FIELD_DP32(data, STATUS, RXEMPTY, 1);
117     s->regs[IBEX_SPI_HOST_STATUS] = data;
118 }
119 
120 static void ibex_spi_txfifo_reset(IbexSPIHostState *s)
121 {
122     uint32_t data = s->regs[IBEX_SPI_HOST_STATUS];
123     /* Empty the TX FIFO and assert TXEMPTY */
124     fifo8_reset(&s->tx_fifo);
125     data = FIELD_DP32(data, STATUS, TXFULL, 0);
126     data = FIELD_DP32(data, STATUS, TXEMPTY, 1);
127     s->regs[IBEX_SPI_HOST_STATUS] = data;
128 }
129 
130 static void ibex_spi_host_reset(DeviceState *dev)
131 {
132     IbexSPIHostState *s = IBEX_SPI_HOST(dev);
133     trace_ibex_spi_host_reset("Resetting Ibex SPI");
134 
135     /* SPI Host Register Reset */
136     s->regs[IBEX_SPI_HOST_INTR_STATE]   = 0x00;
137     s->regs[IBEX_SPI_HOST_INTR_ENABLE]  = 0x00;
138     s->regs[IBEX_SPI_HOST_INTR_TEST]    = 0x00;
139     s->regs[IBEX_SPI_HOST_ALERT_TEST]   = 0x00;
140     s->regs[IBEX_SPI_HOST_CONTROL]      = 0x7f;
141     s->regs[IBEX_SPI_HOST_STATUS]       = 0x00;
142     s->regs[IBEX_SPI_HOST_CONFIGOPTS]   = 0x00;
143     s->regs[IBEX_SPI_HOST_CSID]         = 0x00;
144     s->regs[IBEX_SPI_HOST_COMMAND]      = 0x00;
145     /* RX/TX Modelled by FIFO */
146     s->regs[IBEX_SPI_HOST_RXDATA]       = 0x00;
147     s->regs[IBEX_SPI_HOST_TXDATA]       = 0x00;
148 
149     s->regs[IBEX_SPI_HOST_ERROR_ENABLE] = 0x1F;
150     s->regs[IBEX_SPI_HOST_ERROR_STATUS] = 0x00;
151     s->regs[IBEX_SPI_HOST_EVENT_ENABLE] = 0x00;
152 
153     ibex_spi_rxfifo_reset(s);
154     ibex_spi_txfifo_reset(s);
155 
156     s->init_status = true;
157     return;
158 }
159 
160 /*
161  * Check if we need to trigger an interrupt.
162  * The two interrupts lines (host_err and event) can
163  * be enabled separately in 'IBEX_SPI_HOST_INTR_ENABLE'.
164  *
165  * Interrupts are triggered based on the ones
166  * enabled in the `IBEX_SPI_HOST_EVENT_ENABLE` and `IBEX_SPI_HOST_ERROR_ENABLE`.
167  */
168 static void ibex_spi_host_irq(IbexSPIHostState *s)
169 {
170     uint32_t intr_test_reg = s->regs[IBEX_SPI_HOST_INTR_TEST];
171     uint32_t intr_en_reg = s->regs[IBEX_SPI_HOST_INTR_ENABLE];
172     uint32_t intr_state_reg = s->regs[IBEX_SPI_HOST_INTR_STATE];
173 
174     uint32_t err_en_reg = s->regs[IBEX_SPI_HOST_ERROR_ENABLE];
175     uint32_t event_en_reg = s->regs[IBEX_SPI_HOST_EVENT_ENABLE];
176     uint32_t err_status_reg = s->regs[IBEX_SPI_HOST_ERROR_STATUS];
177     uint32_t status_reg = s->regs[IBEX_SPI_HOST_STATUS];
178 
179 
180     bool error_en = FIELD_EX32(intr_en_reg, INTR_ENABLE, ERROR);
181     bool event_en = FIELD_EX32(intr_en_reg, INTR_ENABLE, SPI_EVENT);
182     bool err_pending = FIELD_EX32(intr_state_reg, INTR_STATE, ERROR);
183     bool status_pending = FIELD_EX32(intr_state_reg, INTR_STATE, SPI_EVENT);
184 
185     int err_irq = 0, event_irq = 0;
186 
187     /* Error IRQ enabled and Error IRQ Cleared */
188     if (error_en && !err_pending) {
189         /* Event enabled, Interrupt Test Error */
190         if (FIELD_EX32(intr_test_reg, INTR_TEST,  ERROR)) {
191             err_irq = 1;
192         } else if (FIELD_EX32(err_en_reg, ERROR_ENABLE,  CMDBUSY) &&
193                    FIELD_EX32(err_status_reg, ERROR_STATUS,  CMDBUSY)) {
194             /* Wrote to COMMAND when not READY */
195             err_irq = 1;
196         } else if (FIELD_EX32(err_en_reg, ERROR_ENABLE,  CMDINVAL)  &&
197                    FIELD_EX32(err_status_reg, ERROR_STATUS,  CMDINVAL)) {
198             /* Invalid command segment */
199             err_irq = 1;
200         } else if (FIELD_EX32(err_en_reg, ERROR_ENABLE,  CSIDINVAL) &&
201                    FIELD_EX32(err_status_reg, ERROR_STATUS,  CSIDINVAL)) {
202             /* Invalid value for CSID */
203             err_irq = 1;
204         }
205         if (err_irq) {
206             s->regs[IBEX_SPI_HOST_INTR_STATE] |= R_INTR_STATE_ERROR_MASK;
207         }
208         qemu_set_irq(s->host_err, err_irq);
209     }
210 
211     /* Event IRQ Enabled and Event IRQ Cleared */
212     if (event_en && !status_pending) {
213         if (FIELD_EX32(intr_test_reg, INTR_STATE,  SPI_EVENT)) {
214             /* Event enabled, Interrupt Test Event */
215             event_irq = 1;
216         } else if (FIELD_EX32(event_en_reg, EVENT_ENABLE,  READY) &&
217                    FIELD_EX32(status_reg, STATUS, READY)) {
218             /* SPI Host ready for next command */
219             event_irq = 1;
220         } else if (FIELD_EX32(event_en_reg, EVENT_ENABLE,  TXEMPTY) &&
221                    FIELD_EX32(status_reg, STATUS,  TXEMPTY)) {
222             /* SPI TXEMPTY, TXFIFO drained */
223             event_irq = 1;
224         } else if (FIELD_EX32(event_en_reg, EVENT_ENABLE,  RXFULL) &&
225                    FIELD_EX32(status_reg, STATUS,  RXFULL)) {
226             /* SPI RXFULL, RXFIFO  full */
227             event_irq = 1;
228         }
229         if (event_irq) {
230             s->regs[IBEX_SPI_HOST_INTR_STATE] |= R_INTR_STATE_SPI_EVENT_MASK;
231         }
232         qemu_set_irq(s->event, event_irq);
233     }
234 }
235 
236 static void ibex_spi_host_transfer(IbexSPIHostState *s)
237 {
238     uint32_t rx, tx, data;
239     /* Get num of one byte transfers */
240     uint8_t segment_len = FIELD_EX32(s->regs[IBEX_SPI_HOST_COMMAND],
241                                      COMMAND,  LEN);
242 
243     while (segment_len > 0) {
244         if (fifo8_is_empty(&s->tx_fifo)) {
245             /* Assert Stall */
246             s->regs[IBEX_SPI_HOST_STATUS] |= R_STATUS_TXSTALL_MASK;
247             break;
248         } else if (fifo8_is_full(&s->rx_fifo)) {
249             /* Assert Stall */
250             s->regs[IBEX_SPI_HOST_STATUS] |= R_STATUS_RXSTALL_MASK;
251             break;
252         } else {
253             tx = fifo8_pop(&s->tx_fifo);
254         }
255 
256         rx = ssi_transfer(s->ssi, tx);
257 
258         trace_ibex_spi_host_transfer(tx, rx);
259 
260         if (!fifo8_is_full(&s->rx_fifo)) {
261             fifo8_push(&s->rx_fifo, rx);
262         } else {
263             /* Assert RXFULL */
264             s->regs[IBEX_SPI_HOST_STATUS] |= R_STATUS_RXFULL_MASK;
265         }
266         --segment_len;
267     }
268 
269     data = s->regs[IBEX_SPI_HOST_STATUS];
270     /* Assert Ready */
271     data = FIELD_DP32(data, STATUS, READY, 1);
272     /* Set RXQD */
273     data = FIELD_DP32(data, STATUS, RXQD, div4_round_up(segment_len));
274     /* Set TXQD */
275     data = FIELD_DP32(data, STATUS, TXQD, fifo8_num_used(&s->tx_fifo) / 4);
276     /* Clear TXFULL */
277     data = FIELD_DP32(data, STATUS, TXFULL, 0);
278     /* Reset RXEMPTY */
279     data = FIELD_DP32(data, STATUS, RXEMPTY, 0);
280     /* Update register status */
281     s->regs[IBEX_SPI_HOST_STATUS] = data;
282     /* Drop remaining bytes that exceed segment_len */
283     ibex_spi_txfifo_reset(s);
284 
285     ibex_spi_host_irq(s);
286 }
287 
288 static uint64_t ibex_spi_host_read(void *opaque, hwaddr addr,
289                                      unsigned int size)
290 {
291     IbexSPIHostState *s = opaque;
292     uint32_t rc = 0;
293     uint8_t rx_byte = 0;
294 
295     trace_ibex_spi_host_read(addr, size);
296 
297     /* Match reg index */
298     addr = addr >> 2;
299     switch (addr) {
300     /* Skipping any W/O registers */
301     case IBEX_SPI_HOST_INTR_STATE...IBEX_SPI_HOST_INTR_ENABLE:
302     case IBEX_SPI_HOST_CONTROL...IBEX_SPI_HOST_STATUS:
303         rc = s->regs[addr];
304         break;
305     case IBEX_SPI_HOST_CSID:
306         rc = s->regs[addr];
307         break;
308     case IBEX_SPI_HOST_CONFIGOPTS:
309         rc = s->config_opts[s->regs[IBEX_SPI_HOST_CSID]];
310         break;
311     case IBEX_SPI_HOST_TXDATA:
312         rc = s->regs[addr];
313         break;
314     case IBEX_SPI_HOST_RXDATA:
315         /* Clear RXFULL */
316         s->regs[IBEX_SPI_HOST_STATUS] &= ~R_STATUS_RXFULL_MASK;
317 
318         for (int i = 0; i < 4; ++i) {
319             if (fifo8_is_empty(&s->rx_fifo)) {
320                 /* Assert RXEMPTY, no IRQ */
321                 s->regs[IBEX_SPI_HOST_STATUS] |= R_STATUS_RXEMPTY_MASK;
322                 s->regs[IBEX_SPI_HOST_ERROR_STATUS] |=
323                                                 R_ERROR_STATUS_UNDERFLOW_MASK;
324                 return rc;
325             }
326             rx_byte = fifo8_pop(&s->rx_fifo);
327             rc |= rx_byte << (i * 8);
328         }
329         break;
330     case IBEX_SPI_HOST_ERROR_ENABLE...IBEX_SPI_HOST_EVENT_ENABLE:
331         rc = s->regs[addr];
332         break;
333     default:
334         qemu_log_mask(LOG_GUEST_ERROR, "Bad offset 0x%" HWADDR_PRIx "\n",
335                       addr << 2);
336     }
337     return rc;
338 }
339 
340 
341 static void ibex_spi_host_write(void *opaque, hwaddr addr,
342                                 uint64_t val64, unsigned int size)
343 {
344     IbexSPIHostState *s = opaque;
345     uint32_t val32 = val64;
346     uint32_t shift_mask = 0xff, status = 0, data = 0;
347     uint8_t txqd_len;
348 
349     trace_ibex_spi_host_write(addr, size, val64);
350 
351     /* Match reg index */
352     addr = addr >> 2;
353 
354     switch (addr) {
355     /* Skipping any R/O registers */
356     case IBEX_SPI_HOST_INTR_STATE:
357         /* rw1c status register */
358         if (FIELD_EX32(val32, INTR_STATE, ERROR)) {
359             data = FIELD_DP32(data, INTR_STATE, ERROR, 0);
360         }
361         if (FIELD_EX32(val32, INTR_STATE, SPI_EVENT)) {
362             data = FIELD_DP32(data, INTR_STATE, SPI_EVENT, 0);
363         }
364         s->regs[addr] = data;
365         break;
366     case IBEX_SPI_HOST_INTR_ENABLE:
367         s->regs[addr] = val32;
368         break;
369     case IBEX_SPI_HOST_INTR_TEST:
370         s->regs[addr] = val32;
371         ibex_spi_host_irq(s);
372         break;
373     case IBEX_SPI_HOST_ALERT_TEST:
374         s->regs[addr] = val32;
375         qemu_log_mask(LOG_UNIMP,
376                         "%s: SPI_ALERT_TEST is not supported\n", __func__);
377         break;
378     case IBEX_SPI_HOST_CONTROL:
379         s->regs[addr] = val32;
380 
381         if (val32 & R_CONTROL_SW_RST_MASK)  {
382             ibex_spi_host_reset((DeviceState *)s);
383             /* Clear active if any */
384             s->regs[IBEX_SPI_HOST_STATUS] &=  ~R_STATUS_ACTIVE_MASK;
385         }
386 
387         if (val32 & R_CONTROL_OUTPUT_EN_MASK)  {
388             qemu_log_mask(LOG_UNIMP,
389                           "%s: CONTROL_OUTPUT_EN is not supported\n", __func__);
390         }
391         break;
392     case IBEX_SPI_HOST_CONFIGOPTS:
393         /* Update the respective config-opts register based on CSIDth index */
394         s->config_opts[s->regs[IBEX_SPI_HOST_CSID]] = val32;
395         qemu_log_mask(LOG_UNIMP,
396                       "%s: CONFIGOPTS Hardware settings not supported\n",
397                          __func__);
398         break;
399     case IBEX_SPI_HOST_CSID:
400         if (val32 >= s->num_cs) {
401             /* CSID exceeds max num_cs */
402             s->regs[IBEX_SPI_HOST_ERROR_STATUS] |=
403                                                 R_ERROR_STATUS_CSIDINVAL_MASK;
404             ibex_spi_host_irq(s);
405             return;
406         }
407         s->regs[addr] = val32;
408         break;
409     case IBEX_SPI_HOST_COMMAND:
410         s->regs[addr] = val32;
411 
412         /* STALL, IP not enabled */
413         if (!(FIELD_EX32(s->regs[IBEX_SPI_HOST_CONTROL],
414                          CONTROL, SPIEN))) {
415             return;
416         }
417 
418         /* SPI not ready, IRQ Error */
419         if (!(FIELD_EX32(s->regs[IBEX_SPI_HOST_STATUS],
420                          STATUS, READY))) {
421             s->regs[IBEX_SPI_HOST_ERROR_STATUS] |= R_ERROR_STATUS_CMDBUSY_MASK;
422             ibex_spi_host_irq(s);
423             return;
424         }
425 
426         /* Assert Not Ready */
427         s->regs[IBEX_SPI_HOST_STATUS] &= ~R_STATUS_READY_MASK;
428 
429         if (FIELD_EX32(val32, COMMAND, DIRECTION) != BIDIRECTIONAL_TRANSFER) {
430             qemu_log_mask(LOG_UNIMP,
431                           "%s: Rx Only/Tx Only are not supported\n", __func__);
432         }
433 
434         if (val32 & R_COMMAND_CSAAT_MASK)  {
435             qemu_log_mask(LOG_UNIMP,
436                           "%s: CSAAT is not supported\n", __func__);
437         }
438         if (val32 & R_COMMAND_SPEED_MASK)  {
439             qemu_log_mask(LOG_UNIMP,
440                           "%s: SPEED is not supported\n", __func__);
441         }
442 
443         /* Set Transfer Callback */
444         timer_mod(s->fifo_trigger_handle,
445                     qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
446                     (TX_INTERRUPT_TRIGGER_DELAY_NS));
447 
448         break;
449     case IBEX_SPI_HOST_TXDATA:
450         /*
451          * This is a hardware `feature` where
452          * the first word written to TXDATA after init is omitted entirely
453          */
454         if (s->init_status) {
455             s->init_status = false;
456             return;
457         }
458 
459         for (int i = 0; i < 4; ++i) {
460             /* Attempting to write when TXFULL */
461             if (fifo8_is_full(&s->tx_fifo)) {
462                 /* Assert RXEMPTY, no IRQ */
463                 s->regs[IBEX_SPI_HOST_STATUS] |= R_STATUS_TXFULL_MASK;
464                 s->regs[IBEX_SPI_HOST_ERROR_STATUS] |=
465                                                  R_ERROR_STATUS_OVERFLOW_MASK;
466                 ibex_spi_host_irq(s);
467                 return;
468             }
469             /* Byte ordering is set by the IP */
470             status = s->regs[IBEX_SPI_HOST_STATUS];
471             if (FIELD_EX32(status, STATUS, BYTEORDER) == 0) {
472                 /* LE: LSB transmitted first (default for ibex processor) */
473                 shift_mask = 0xff << (i * 8);
474             } else {
475                 /* BE: MSB transmitted first */
476                 qemu_log_mask(LOG_UNIMP,
477                              "%s: Big endian is not supported\n", __func__);
478             }
479 
480             fifo8_push(&s->tx_fifo, (val32 & shift_mask) >> (i * 8));
481         }
482         status = s->regs[IBEX_SPI_HOST_STATUS];
483         /* Reset TXEMPTY */
484         status = FIELD_DP32(status, STATUS, TXEMPTY, 0);
485         /* Update TXQD */
486         txqd_len = FIELD_EX32(status, STATUS, TXQD);
487         /* Partial bytes (size < 4) are padded, in words. */
488         txqd_len += 1;
489         status = FIELD_DP32(status, STATUS, TXQD, txqd_len);
490         /* Assert Ready */
491         status = FIELD_DP32(status, STATUS, READY, 1);
492         /* Update register status */
493         s->regs[IBEX_SPI_HOST_STATUS] = status;
494         break;
495     case IBEX_SPI_HOST_ERROR_ENABLE:
496         s->regs[addr] = val32;
497 
498         if (val32 & R_ERROR_ENABLE_CMDINVAL_MASK)  {
499             qemu_log_mask(LOG_UNIMP,
500                           "%s: Segment Length is not supported\n", __func__);
501         }
502         break;
503     case IBEX_SPI_HOST_ERROR_STATUS:
504     /*
505      *  Indicates any errors that have occurred.
506      *  When an error occurs, the corresponding bit must be cleared
507      *  here before issuing any further commands
508      */
509         status = s->regs[addr];
510         /* rw1c status register */
511         if (FIELD_EX32(val32, ERROR_STATUS, CMDBUSY)) {
512             status = FIELD_DP32(status, ERROR_STATUS, CMDBUSY, 0);
513         }
514         if (FIELD_EX32(val32, ERROR_STATUS, OVERFLOW)) {
515             status = FIELD_DP32(status, ERROR_STATUS, OVERFLOW, 0);
516         }
517         if (FIELD_EX32(val32, ERROR_STATUS, UNDERFLOW)) {
518             status = FIELD_DP32(status, ERROR_STATUS, UNDERFLOW, 0);
519         }
520         if (FIELD_EX32(val32, ERROR_STATUS, CMDINVAL)) {
521             status = FIELD_DP32(status, ERROR_STATUS, CMDINVAL, 0);
522         }
523         if (FIELD_EX32(val32, ERROR_STATUS, CSIDINVAL)) {
524             status = FIELD_DP32(status, ERROR_STATUS, CSIDINVAL, 0);
525         }
526         if (FIELD_EX32(val32, ERROR_STATUS, ACCESSINVAL)) {
527             status = FIELD_DP32(status, ERROR_STATUS, ACCESSINVAL, 0);
528         }
529         s->regs[addr] = status;
530         break;
531     case IBEX_SPI_HOST_EVENT_ENABLE:
532     /* Controls which classes of SPI events raise an interrupt. */
533         s->regs[addr] = val32;
534 
535         if (val32 & R_EVENT_ENABLE_RXWM_MASK)  {
536             qemu_log_mask(LOG_UNIMP,
537                           "%s: RXWM is not supported\n", __func__);
538         }
539         if (val32 & R_EVENT_ENABLE_TXWM_MASK)  {
540             qemu_log_mask(LOG_UNIMP,
541                           "%s: TXWM is not supported\n", __func__);
542         }
543 
544         if (val32 & R_EVENT_ENABLE_IDLE_MASK)  {
545             qemu_log_mask(LOG_UNIMP,
546                           "%s: IDLE is not supported\n", __func__);
547         }
548         break;
549     default:
550         qemu_log_mask(LOG_GUEST_ERROR, "Bad offset 0x%" HWADDR_PRIx "\n",
551                       addr << 2);
552     }
553 }
554 
555 static const MemoryRegionOps ibex_spi_ops = {
556     .read = ibex_spi_host_read,
557     .write = ibex_spi_host_write,
558     /* Ibex default LE */
559     .endianness = DEVICE_LITTLE_ENDIAN,
560 };
561 
562 static Property ibex_spi_properties[] = {
563     DEFINE_PROP_UINT32("num_cs", IbexSPIHostState, num_cs, 1),
564     DEFINE_PROP_END_OF_LIST(),
565 };
566 
567 static const VMStateDescription vmstate_ibex = {
568     .name = TYPE_IBEX_SPI_HOST,
569     .version_id = 1,
570     .minimum_version_id = 1,
571     .fields = (VMStateField[]) {
572         VMSTATE_UINT32_ARRAY(regs, IbexSPIHostState, IBEX_SPI_HOST_MAX_REGS),
573         VMSTATE_VARRAY_UINT32(config_opts, IbexSPIHostState,
574                               num_cs, 0, vmstate_info_uint32, uint32_t),
575         VMSTATE_FIFO8(rx_fifo, IbexSPIHostState),
576         VMSTATE_FIFO8(tx_fifo, IbexSPIHostState),
577         VMSTATE_TIMER_PTR(fifo_trigger_handle, IbexSPIHostState),
578         VMSTATE_BOOL(init_status, IbexSPIHostState),
579         VMSTATE_END_OF_LIST()
580     }
581 };
582 
583 static void fifo_trigger_update(void *opaque)
584 {
585     IbexSPIHostState *s = opaque;
586     ibex_spi_host_transfer(s);
587 }
588 
589 static void ibex_spi_host_realize(DeviceState *dev, Error **errp)
590 {
591     IbexSPIHostState *s = IBEX_SPI_HOST(dev);
592     int i;
593 
594     s->ssi = ssi_create_bus(dev, "ssi");
595     s->cs_lines = g_new0(qemu_irq, s->num_cs);
596 
597     for (i = 0; i < s->num_cs; ++i) {
598         sysbus_init_irq(SYS_BUS_DEVICE(dev), &s->cs_lines[i]);
599     }
600 
601     /* Setup CONFIGOPTS Multi-register */
602     s->config_opts = g_new0(uint32_t, s->num_cs);
603 
604     /* Setup FIFO Interrupt Timer */
605     s->fifo_trigger_handle = timer_new_ns(QEMU_CLOCK_VIRTUAL,
606                                           fifo_trigger_update, s);
607 
608     /* FIFO sizes as per OT Spec */
609     fifo8_create(&s->tx_fifo, IBEX_SPI_HOST_TXFIFO_LEN);
610     fifo8_create(&s->rx_fifo, IBEX_SPI_HOST_RXFIFO_LEN);
611 }
612 
613 static void ibex_spi_host_init(Object *obj)
614 {
615     IbexSPIHostState *s = IBEX_SPI_HOST(obj);
616 
617     sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->host_err);
618     sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->event);
619 
620     memory_region_init_io(&s->mmio, obj, &ibex_spi_ops, s,
621                           TYPE_IBEX_SPI_HOST, 0x1000);
622     sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio);
623 }
624 
625 static void ibex_spi_host_class_init(ObjectClass *klass, void *data)
626 {
627     DeviceClass *dc = DEVICE_CLASS(klass);
628     dc->realize = ibex_spi_host_realize;
629     dc->reset = ibex_spi_host_reset;
630     dc->vmsd = &vmstate_ibex;
631     device_class_set_props(dc, ibex_spi_properties);
632 }
633 
634 static const TypeInfo ibex_spi_host_info = {
635     .name          = TYPE_IBEX_SPI_HOST,
636     .parent        = TYPE_SYS_BUS_DEVICE,
637     .instance_size = sizeof(IbexSPIHostState),
638     .instance_init = ibex_spi_host_init,
639     .class_init    = ibex_spi_host_class_init,
640 };
641 
642 static void ibex_spi_host_register_types(void)
643 {
644     type_register_static(&ibex_spi_host_info);
645 }
646 
647 type_init(ibex_spi_host_register_types)
648