xref: /openbmc/qemu/hw/ssi/ibex_spi_host.c (revision ffe98631)
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/ssi/ibex_spi_host.h"
30 #include "hw/irq.h"
31 #include "hw/qdev-properties.h"
32 #include "hw/qdev-properties-system.h"
33 #include "migration/vmstate.h"
34 #include "trace.h"
35 
36 REG32(INTR_STATE, 0x00)
37     FIELD(INTR_STATE, ERROR, 0, 1)
38     FIELD(INTR_STATE, SPI_EVENT, 1, 1)
39 REG32(INTR_ENABLE, 0x04)
40     FIELD(INTR_ENABLE, ERROR, 0, 1)
41     FIELD(INTR_ENABLE, SPI_EVENT, 1, 1)
42 REG32(INTR_TEST, 0x08)
43     FIELD(INTR_TEST, ERROR, 0, 1)
44     FIELD(INTR_TEST, SPI_EVENT, 1, 1)
45 REG32(ALERT_TEST, 0x0c)
46     FIELD(ALERT_TEST, FETAL_TEST, 0, 1)
47 REG32(CONTROL, 0x10)
48     FIELD(CONTROL, RX_WATERMARK, 0, 8)
49     FIELD(CONTROL, TX_WATERMARK, 1, 8)
50     FIELD(CONTROL, OUTPUT_EN, 29, 1)
51     FIELD(CONTROL, SW_RST, 30, 1)
52     FIELD(CONTROL, SPIEN, 31, 1)
53 REG32(STATUS, 0x14)
54     FIELD(STATUS, TXQD, 0, 8)
55     FIELD(STATUS, RXQD, 18, 8)
56     FIELD(STATUS, CMDQD, 16, 3)
57     FIELD(STATUS, RXWM, 20, 1)
58     FIELD(STATUS, BYTEORDER, 22, 1)
59     FIELD(STATUS, RXSTALL, 23, 1)
60     FIELD(STATUS, RXEMPTY, 24, 1)
61     FIELD(STATUS, RXFULL, 25, 1)
62     FIELD(STATUS, TXWM, 26, 1)
63     FIELD(STATUS, TXSTALL, 27, 1)
64     FIELD(STATUS, TXEMPTY, 28, 1)
65     FIELD(STATUS, TXFULL, 29, 1)
66     FIELD(STATUS, ACTIVE, 30, 1)
67     FIELD(STATUS, READY, 31, 1)
68 REG32(CONFIGOPTS, 0x18)
69     FIELD(CONFIGOPTS, CLKDIV_0, 0, 16)
70     FIELD(CONFIGOPTS, CSNIDLE_0, 16, 4)
71     FIELD(CONFIGOPTS, CSNTRAIL_0, 20, 4)
72     FIELD(CONFIGOPTS, CSNLEAD_0, 24, 4)
73     FIELD(CONFIGOPTS, FULLCYC_0, 29, 1)
74     FIELD(CONFIGOPTS, CPHA_0, 30, 1)
75     FIELD(CONFIGOPTS, CPOL_0, 31, 1)
76 REG32(CSID, 0x1c)
77     FIELD(CSID, CSID, 0, 32)
78 REG32(COMMAND, 0x20)
79     FIELD(COMMAND, LEN, 0, 8)
80     FIELD(COMMAND, CSAAT, 9, 1)
81     FIELD(COMMAND, SPEED, 10, 2)
82     FIELD(COMMAND, DIRECTION, 12, 2)
83 REG32(ERROR_ENABLE, 0x2c)
84     FIELD(ERROR_ENABLE, CMDBUSY, 0, 1)
85     FIELD(ERROR_ENABLE, OVERFLOW, 1, 1)
86     FIELD(ERROR_ENABLE, UNDERFLOW, 2, 1)
87     FIELD(ERROR_ENABLE, CMDINVAL, 3, 1)
88     FIELD(ERROR_ENABLE, CSIDINVAL, 4, 1)
89 REG32(ERROR_STATUS, 0x30)
90     FIELD(ERROR_STATUS, CMDBUSY, 0, 1)
91     FIELD(ERROR_STATUS, OVERFLOW, 1, 1)
92     FIELD(ERROR_STATUS, UNDERFLOW, 2, 1)
93     FIELD(ERROR_STATUS, CMDINVAL, 3, 1)
94     FIELD(ERROR_STATUS, CSIDINVAL, 4, 1)
95     FIELD(ERROR_STATUS, ACCESSINVAL, 5, 1)
96 REG32(EVENT_ENABLE, 0x34)
97     FIELD(EVENT_ENABLE, RXFULL, 0, 1)
98     FIELD(EVENT_ENABLE, TXEMPTY, 1, 1)
99     FIELD(EVENT_ENABLE, RXWM, 2, 1)
100     FIELD(EVENT_ENABLE, TXWM, 3, 1)
101     FIELD(EVENT_ENABLE, READY, 4, 1)
102     FIELD(EVENT_ENABLE, IDLE, 5, 1)
103 
104 static inline uint8_t div4_round_up(uint8_t dividend)
105 {
106     return (dividend + 3) / 4;
107 }
108 
109 static void ibex_spi_rxfifo_reset(IbexSPIHostState *s)
110 {
111     uint32_t data = s->regs[IBEX_SPI_HOST_STATUS];
112     /* Empty the RX FIFO and assert RXEMPTY */
113     fifo8_reset(&s->rx_fifo);
114     data = FIELD_DP32(data, STATUS, RXFULL, 0);
115     data = FIELD_DP32(data, STATUS, RXEMPTY, 1);
116     s->regs[IBEX_SPI_HOST_STATUS] = data;
117 }
118 
119 static void ibex_spi_txfifo_reset(IbexSPIHostState *s)
120 {
121     uint32_t data = s->regs[IBEX_SPI_HOST_STATUS];
122     /* Empty the TX FIFO and assert TXEMPTY */
123     fifo8_reset(&s->tx_fifo);
124     data = FIELD_DP32(data, STATUS, TXFULL, 0);
125     data = FIELD_DP32(data, STATUS, TXEMPTY, 1);
126     s->regs[IBEX_SPI_HOST_STATUS] = data;
127 }
128 
129 static void ibex_spi_host_reset(DeviceState *dev)
130 {
131     IbexSPIHostState *s = IBEX_SPI_HOST(dev);
132     trace_ibex_spi_host_reset("Resetting Ibex SPI");
133 
134     /* SPI Host Register Reset */
135     s->regs[IBEX_SPI_HOST_INTR_STATE]   = 0x00;
136     s->regs[IBEX_SPI_HOST_INTR_ENABLE]  = 0x00;
137     s->regs[IBEX_SPI_HOST_INTR_TEST]    = 0x00;
138     s->regs[IBEX_SPI_HOST_ALERT_TEST]   = 0x00;
139     s->regs[IBEX_SPI_HOST_CONTROL]      = 0x7f;
140     s->regs[IBEX_SPI_HOST_STATUS]       = 0x00;
141     s->regs[IBEX_SPI_HOST_CONFIGOPTS]   = 0x00;
142     s->regs[IBEX_SPI_HOST_CSID]         = 0x00;
143     s->regs[IBEX_SPI_HOST_COMMAND]      = 0x00;
144     /* RX/TX Modelled by FIFO */
145     s->regs[IBEX_SPI_HOST_RXDATA]       = 0x00;
146     s->regs[IBEX_SPI_HOST_TXDATA]       = 0x00;
147 
148     s->regs[IBEX_SPI_HOST_ERROR_ENABLE] = 0x1F;
149     s->regs[IBEX_SPI_HOST_ERROR_STATUS] = 0x00;
150     s->regs[IBEX_SPI_HOST_EVENT_ENABLE] = 0x00;
151 
152     ibex_spi_rxfifo_reset(s);
153     ibex_spi_txfifo_reset(s);
154 
155     s->init_status = true;
156     return;
157 }
158 
159 /*
160  * Check if we need to trigger an interrupt.
161  * The two interrupts lines (host_err and event) can
162  * be enabled separately in 'IBEX_SPI_HOST_INTR_ENABLE'.
163  *
164  * Interrupts are triggered based on the ones
165  * enabled in the `IBEX_SPI_HOST_EVENT_ENABLE` and `IBEX_SPI_HOST_ERROR_ENABLE`.
166  */
167 static void ibex_spi_host_irq(IbexSPIHostState *s)
168 {
169     uint32_t intr_test_reg = s->regs[IBEX_SPI_HOST_INTR_TEST];
170     uint32_t intr_en_reg = s->regs[IBEX_SPI_HOST_INTR_ENABLE];
171     uint32_t intr_state_reg = s->regs[IBEX_SPI_HOST_INTR_STATE];
172 
173     uint32_t err_en_reg = s->regs[IBEX_SPI_HOST_ERROR_ENABLE];
174     uint32_t event_en_reg = s->regs[IBEX_SPI_HOST_EVENT_ENABLE];
175     uint32_t err_status_reg = s->regs[IBEX_SPI_HOST_ERROR_STATUS];
176     uint32_t status_reg = s->regs[IBEX_SPI_HOST_STATUS];
177 
178 
179     bool error_en = FIELD_EX32(intr_en_reg, INTR_ENABLE, ERROR);
180     bool event_en = FIELD_EX32(intr_en_reg, INTR_ENABLE, SPI_EVENT);
181     bool err_pending = FIELD_EX32(intr_state_reg, INTR_STATE, ERROR);
182     bool status_pending = FIELD_EX32(intr_state_reg, INTR_STATE, SPI_EVENT);
183 
184     int err_irq = 0, event_irq = 0;
185 
186     /* Error IRQ enabled and Error IRQ Cleared */
187     if (error_en && !err_pending) {
188         /* Event enabled, Interrupt Test Error */
189         if (FIELD_EX32(intr_test_reg, INTR_TEST,  ERROR)) {
190             err_irq = 1;
191         } else if (FIELD_EX32(err_en_reg, ERROR_ENABLE,  CMDBUSY) &&
192                    FIELD_EX32(err_status_reg, ERROR_STATUS,  CMDBUSY)) {
193             /* Wrote to COMMAND when not READY */
194             err_irq = 1;
195         } else if (FIELD_EX32(err_en_reg, ERROR_ENABLE,  CMDINVAL)  &&
196                    FIELD_EX32(err_status_reg, ERROR_STATUS,  CMDINVAL)) {
197             /* Invalid command segment */
198             err_irq = 1;
199         } else if (FIELD_EX32(err_en_reg, ERROR_ENABLE,  CSIDINVAL) &&
200                    FIELD_EX32(err_status_reg, ERROR_STATUS,  CSIDINVAL)) {
201             /* Invalid value for CSID */
202             err_irq = 1;
203         }
204         if (err_irq) {
205             s->regs[IBEX_SPI_HOST_INTR_STATE] |= R_INTR_STATE_ERROR_MASK;
206         }
207         qemu_set_irq(s->host_err, err_irq);
208     }
209 
210     /* Event IRQ Enabled and Event IRQ Cleared */
211     if (event_en && !status_pending) {
212         if (FIELD_EX32(intr_test_reg, INTR_STATE,  SPI_EVENT)) {
213             /* Event enabled, Interrupt Test Event */
214             event_irq = 1;
215         } else if (FIELD_EX32(event_en_reg, EVENT_ENABLE,  READY) &&
216                    FIELD_EX32(status_reg, STATUS, READY)) {
217             /* SPI Host ready for next command */
218             event_irq = 1;
219         } else if (FIELD_EX32(event_en_reg, EVENT_ENABLE,  TXEMPTY) &&
220                    FIELD_EX32(status_reg, STATUS,  TXEMPTY)) {
221             /* SPI TXEMPTY, TXFIFO drained */
222             event_irq = 1;
223         } else if (FIELD_EX32(event_en_reg, EVENT_ENABLE,  RXFULL) &&
224                    FIELD_EX32(status_reg, STATUS,  RXFULL)) {
225             /* SPI RXFULL, RXFIFO  full */
226             event_irq = 1;
227         }
228         if (event_irq) {
229             s->regs[IBEX_SPI_HOST_INTR_STATE] |= R_INTR_STATE_SPI_EVENT_MASK;
230         }
231         qemu_set_irq(s->event, event_irq);
232     }
233 }
234 
235 static void ibex_spi_host_transfer(IbexSPIHostState *s)
236 {
237     uint32_t rx, tx, data;
238     /* Get num of one byte transfers */
239     uint8_t segment_len = FIELD_EX32(s->regs[IBEX_SPI_HOST_COMMAND],
240                                      COMMAND,  LEN);
241 
242     while (segment_len > 0) {
243         if (fifo8_is_empty(&s->tx_fifo)) {
244             /* Assert Stall */
245             s->regs[IBEX_SPI_HOST_STATUS] |= R_STATUS_TXSTALL_MASK;
246             break;
247         } else if (fifo8_is_full(&s->rx_fifo)) {
248             /* Assert Stall */
249             s->regs[IBEX_SPI_HOST_STATUS] |= R_STATUS_RXSTALL_MASK;
250             break;
251         } else {
252             tx = fifo8_pop(&s->tx_fifo);
253         }
254 
255         rx = ssi_transfer(s->ssi, tx);
256 
257         trace_ibex_spi_host_transfer(tx, rx);
258 
259         if (!fifo8_is_full(&s->rx_fifo)) {
260             fifo8_push(&s->rx_fifo, rx);
261         } else {
262             /* Assert RXFULL */
263             s->regs[IBEX_SPI_HOST_STATUS] |= R_STATUS_RXFULL_MASK;
264         }
265         --segment_len;
266     }
267 
268     data = s->regs[IBEX_SPI_HOST_STATUS];
269     /* Assert Ready */
270     data = FIELD_DP32(data, STATUS, READY, 1);
271     /* Set RXQD */
272     data = FIELD_DP32(data, STATUS, RXQD, div4_round_up(segment_len));
273     /* Set TXQD */
274     data = FIELD_DP32(data, STATUS, TXQD, fifo8_num_used(&s->tx_fifo) / 4);
275     /* Clear TXFULL */
276     data = FIELD_DP32(data, STATUS, TXFULL, 0);
277     /* Reset RXEMPTY */
278     data = FIELD_DP32(data, STATUS, RXEMPTY, 0);
279     /* Update register status */
280     s->regs[IBEX_SPI_HOST_STATUS] = data;
281     /* Drop remaining bytes that exceed segment_len */
282     ibex_spi_txfifo_reset(s);
283 
284     ibex_spi_host_irq(s);
285 }
286 
287 static uint64_t ibex_spi_host_read(void *opaque, hwaddr addr,
288                                      unsigned int size)
289 {
290     IbexSPIHostState *s = opaque;
291     uint32_t rc = 0;
292     uint8_t rx_byte = 0;
293 
294     trace_ibex_spi_host_read(addr, size);
295 
296     /* Match reg index */
297     addr = addr >> 2;
298     switch (addr) {
299     /* Skipping any W/O registers */
300     case IBEX_SPI_HOST_INTR_STATE...IBEX_SPI_HOST_INTR_ENABLE:
301     case IBEX_SPI_HOST_CONTROL...IBEX_SPI_HOST_STATUS:
302         rc = s->regs[addr];
303         break;
304     case IBEX_SPI_HOST_CSID:
305         rc = s->regs[addr];
306         break;
307     case IBEX_SPI_HOST_CONFIGOPTS:
308         rc = s->config_opts[s->regs[IBEX_SPI_HOST_CSID]];
309         break;
310     case IBEX_SPI_HOST_TXDATA:
311         rc = s->regs[addr];
312         break;
313     case IBEX_SPI_HOST_RXDATA:
314         /* Clear RXFULL */
315         s->regs[IBEX_SPI_HOST_STATUS] &= ~R_STATUS_RXFULL_MASK;
316 
317         for (int i = 0; i < 4; ++i) {
318             if (fifo8_is_empty(&s->rx_fifo)) {
319                 /* Assert RXEMPTY, no IRQ */
320                 s->regs[IBEX_SPI_HOST_STATUS] |= R_STATUS_RXEMPTY_MASK;
321                 s->regs[IBEX_SPI_HOST_ERROR_STATUS] |=
322                                                 R_ERROR_STATUS_UNDERFLOW_MASK;
323                 return rc;
324             }
325             rx_byte = fifo8_pop(&s->rx_fifo);
326             rc |= rx_byte << (i * 8);
327         }
328         break;
329     case IBEX_SPI_HOST_ERROR_ENABLE...IBEX_SPI_HOST_EVENT_ENABLE:
330         rc = s->regs[addr];
331         break;
332     default:
333         qemu_log_mask(LOG_GUEST_ERROR, "Bad offset 0x%" HWADDR_PRIx "\n",
334                       addr << 2);
335     }
336     return rc;
337 }
338 
339 
340 static void ibex_spi_host_write(void *opaque, hwaddr addr,
341                                 uint64_t val64, unsigned int size)
342 {
343     IbexSPIHostState *s = opaque;
344     uint32_t val32 = val64;
345     uint32_t shift_mask = 0xff, status = 0, data = 0;
346     uint8_t txqd_len;
347 
348     trace_ibex_spi_host_write(addr, size, val64);
349 
350     /* Match reg index */
351     addr = addr >> 2;
352 
353     switch (addr) {
354     /* Skipping any R/O registers */
355     case IBEX_SPI_HOST_INTR_STATE:
356         /* rw1c status register */
357         if (FIELD_EX32(val32, INTR_STATE, ERROR)) {
358             data = FIELD_DP32(data, INTR_STATE, ERROR, 0);
359         }
360         if (FIELD_EX32(val32, INTR_STATE, SPI_EVENT)) {
361             data = FIELD_DP32(data, INTR_STATE, SPI_EVENT, 0);
362         }
363         s->regs[addr] = data;
364         break;
365     case IBEX_SPI_HOST_INTR_ENABLE:
366         s->regs[addr] = val32;
367         break;
368     case IBEX_SPI_HOST_INTR_TEST:
369         s->regs[addr] = val32;
370         ibex_spi_host_irq(s);
371         break;
372     case IBEX_SPI_HOST_ALERT_TEST:
373         s->regs[addr] = val32;
374         qemu_log_mask(LOG_UNIMP,
375                         "%s: SPI_ALERT_TEST is not supported\n", __func__);
376         break;
377     case IBEX_SPI_HOST_CONTROL:
378         s->regs[addr] = val32;
379 
380         if (val32 & R_CONTROL_SW_RST_MASK)  {
381             ibex_spi_host_reset((DeviceState *)s);
382             /* Clear active if any */
383             s->regs[IBEX_SPI_HOST_STATUS] &=  ~R_STATUS_ACTIVE_MASK;
384         }
385 
386         if (val32 & R_CONTROL_OUTPUT_EN_MASK)  {
387             qemu_log_mask(LOG_UNIMP,
388                           "%s: CONTROL_OUTPUT_EN is not supported\n", __func__);
389         }
390         break;
391     case IBEX_SPI_HOST_CONFIGOPTS:
392         /* Update the respective config-opts register based on CSIDth index */
393         s->config_opts[s->regs[IBEX_SPI_HOST_CSID]] = val32;
394         qemu_log_mask(LOG_UNIMP,
395                       "%s: CONFIGOPTS Hardware settings not supported\n",
396                          __func__);
397         break;
398     case IBEX_SPI_HOST_CSID:
399         if (val32 >= s->num_cs) {
400             /* CSID exceeds max num_cs */
401             s->regs[IBEX_SPI_HOST_ERROR_STATUS] |=
402                                                 R_ERROR_STATUS_CSIDINVAL_MASK;
403             ibex_spi_host_irq(s);
404             return;
405         }
406         s->regs[addr] = val32;
407         break;
408     case IBEX_SPI_HOST_COMMAND:
409         s->regs[addr] = val32;
410 
411         /* STALL, IP not enabled */
412         if (!(FIELD_EX32(s->regs[IBEX_SPI_HOST_CONTROL],
413                          CONTROL, SPIEN))) {
414             return;
415         }
416 
417         /* SPI not ready, IRQ Error */
418         if (!(FIELD_EX32(s->regs[IBEX_SPI_HOST_STATUS],
419                          STATUS, READY))) {
420             s->regs[IBEX_SPI_HOST_ERROR_STATUS] |= R_ERROR_STATUS_CMDBUSY_MASK;
421             ibex_spi_host_irq(s);
422             return;
423         }
424 
425         /* Assert Not Ready */
426         s->regs[IBEX_SPI_HOST_STATUS] &= ~R_STATUS_READY_MASK;
427 
428         if (FIELD_EX32(val32, COMMAND, DIRECTION) != BIDIRECTIONAL_TRANSFER) {
429             qemu_log_mask(LOG_UNIMP,
430                           "%s: Rx Only/Tx Only are not supported\n", __func__);
431         }
432 
433         if (val32 & R_COMMAND_CSAAT_MASK)  {
434             qemu_log_mask(LOG_UNIMP,
435                           "%s: CSAAT is not supported\n", __func__);
436         }
437         if (val32 & R_COMMAND_SPEED_MASK)  {
438             qemu_log_mask(LOG_UNIMP,
439                           "%s: SPEED is not supported\n", __func__);
440         }
441 
442         /* Set Transfer Callback */
443         timer_mod(s->fifo_trigger_handle,
444                     qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
445                     (TX_INTERRUPT_TRIGGER_DELAY_NS));
446 
447         break;
448     case IBEX_SPI_HOST_TXDATA:
449         /*
450          * This is a hardware `feature` where
451          * the first word written to TXDATA after init is omitted entirely
452          */
453         if (s->init_status) {
454             s->init_status = false;
455             return;
456         }
457 
458         for (int i = 0; i < 4; ++i) {
459             /* Attempting to write when TXFULL */
460             if (fifo8_is_full(&s->tx_fifo)) {
461                 /* Assert RXEMPTY, no IRQ */
462                 s->regs[IBEX_SPI_HOST_STATUS] |= R_STATUS_TXFULL_MASK;
463                 s->regs[IBEX_SPI_HOST_ERROR_STATUS] |=
464                                                  R_ERROR_STATUS_OVERFLOW_MASK;
465                 ibex_spi_host_irq(s);
466                 return;
467             }
468             /* Byte ordering is set by the IP */
469             status = s->regs[IBEX_SPI_HOST_STATUS];
470             if (FIELD_EX32(status, STATUS, BYTEORDER) == 0) {
471                 /* LE: LSB transmitted first (default for ibex processor) */
472                 shift_mask = 0xff << (i * 8);
473             } else {
474                 /* BE: MSB transmitted first */
475                 qemu_log_mask(LOG_UNIMP,
476                              "%s: Big endian is not supported\n", __func__);
477             }
478 
479             fifo8_push(&s->tx_fifo, (val32 & shift_mask) >> (i * 8));
480         }
481         status = s->regs[IBEX_SPI_HOST_STATUS];
482         /* Reset TXEMPTY */
483         status = FIELD_DP32(status, STATUS, TXEMPTY, 0);
484         /* Update TXQD */
485         txqd_len = FIELD_EX32(status, STATUS, TXQD);
486         /* Partial bytes (size < 4) are padded, in words. */
487         txqd_len += 1;
488         status = FIELD_DP32(status, STATUS, TXQD, txqd_len);
489         /* Assert Ready */
490         status = FIELD_DP32(status, STATUS, READY, 1);
491         /* Update register status */
492         s->regs[IBEX_SPI_HOST_STATUS] = status;
493         break;
494     case IBEX_SPI_HOST_ERROR_ENABLE:
495         s->regs[addr] = val32;
496 
497         if (val32 & R_ERROR_ENABLE_CMDINVAL_MASK)  {
498             qemu_log_mask(LOG_UNIMP,
499                           "%s: Segment Length is not supported\n", __func__);
500         }
501         break;
502     case IBEX_SPI_HOST_ERROR_STATUS:
503     /*
504      *  Indicates any errors that have occurred.
505      *  When an error occurs, the corresponding bit must be cleared
506      *  here before issuing any further commands
507      */
508         status = s->regs[addr];
509         /* rw1c status register */
510         if (FIELD_EX32(val32, ERROR_STATUS, CMDBUSY)) {
511             status = FIELD_DP32(status, ERROR_STATUS, CMDBUSY, 0);
512         }
513         if (FIELD_EX32(val32, ERROR_STATUS, OVERFLOW)) {
514             status = FIELD_DP32(status, ERROR_STATUS, OVERFLOW, 0);
515         }
516         if (FIELD_EX32(val32, ERROR_STATUS, UNDERFLOW)) {
517             status = FIELD_DP32(status, ERROR_STATUS, UNDERFLOW, 0);
518         }
519         if (FIELD_EX32(val32, ERROR_STATUS, CMDINVAL)) {
520             status = FIELD_DP32(status, ERROR_STATUS, CMDINVAL, 0);
521         }
522         if (FIELD_EX32(val32, ERROR_STATUS, CSIDINVAL)) {
523             status = FIELD_DP32(status, ERROR_STATUS, CSIDINVAL, 0);
524         }
525         if (FIELD_EX32(val32, ERROR_STATUS, ACCESSINVAL)) {
526             status = FIELD_DP32(status, ERROR_STATUS, ACCESSINVAL, 0);
527         }
528         s->regs[addr] = status;
529         break;
530     case IBEX_SPI_HOST_EVENT_ENABLE:
531     /* Controls which classes of SPI events raise an interrupt. */
532         s->regs[addr] = val32;
533 
534         if (val32 & R_EVENT_ENABLE_RXWM_MASK)  {
535             qemu_log_mask(LOG_UNIMP,
536                           "%s: RXWM is not supported\n", __func__);
537         }
538         if (val32 & R_EVENT_ENABLE_TXWM_MASK)  {
539             qemu_log_mask(LOG_UNIMP,
540                           "%s: TXWM is not supported\n", __func__);
541         }
542 
543         if (val32 & R_EVENT_ENABLE_IDLE_MASK)  {
544             qemu_log_mask(LOG_UNIMP,
545                           "%s: IDLE is not supported\n", __func__);
546         }
547         break;
548     default:
549         qemu_log_mask(LOG_GUEST_ERROR, "Bad offset 0x%" HWADDR_PRIx "\n",
550                       addr << 2);
551     }
552 }
553 
554 static const MemoryRegionOps ibex_spi_ops = {
555     .read = ibex_spi_host_read,
556     .write = ibex_spi_host_write,
557     /* Ibex default LE */
558     .endianness = DEVICE_LITTLE_ENDIAN,
559 };
560 
561 static Property ibex_spi_properties[] = {
562     DEFINE_PROP_UINT32("num_cs", IbexSPIHostState, num_cs, 1),
563     DEFINE_PROP_END_OF_LIST(),
564 };
565 
566 static const VMStateDescription vmstate_ibex = {
567     .name = TYPE_IBEX_SPI_HOST,
568     .version_id = 1,
569     .minimum_version_id = 1,
570     .fields = (VMStateField[]) {
571         VMSTATE_UINT32_ARRAY(regs, IbexSPIHostState, IBEX_SPI_HOST_MAX_REGS),
572         VMSTATE_VARRAY_UINT32(config_opts, IbexSPIHostState,
573                               num_cs, 0, vmstate_info_uint32, uint32_t),
574         VMSTATE_FIFO8(rx_fifo, IbexSPIHostState),
575         VMSTATE_FIFO8(tx_fifo, IbexSPIHostState),
576         VMSTATE_TIMER_PTR(fifo_trigger_handle, IbexSPIHostState),
577         VMSTATE_BOOL(init_status, IbexSPIHostState),
578         VMSTATE_END_OF_LIST()
579     }
580 };
581 
582 static void fifo_trigger_update(void *opaque)
583 {
584     IbexSPIHostState *s = opaque;
585     ibex_spi_host_transfer(s);
586 }
587 
588 static void ibex_spi_host_realize(DeviceState *dev, Error **errp)
589 {
590     IbexSPIHostState *s = IBEX_SPI_HOST(dev);
591     int i;
592 
593     s->ssi = ssi_create_bus(dev, "ssi");
594     s->cs_lines = g_new0(qemu_irq, s->num_cs);
595 
596     for (i = 0; i < s->num_cs; ++i) {
597         sysbus_init_irq(SYS_BUS_DEVICE(dev), &s->cs_lines[i]);
598     }
599 
600     /* Setup CONFIGOPTS Multi-register */
601     s->config_opts = g_new0(uint32_t, s->num_cs);
602 
603     /* Setup FIFO Interrupt Timer */
604     s->fifo_trigger_handle = timer_new_ns(QEMU_CLOCK_VIRTUAL,
605                                           fifo_trigger_update, s);
606 
607     /* FIFO sizes as per OT Spec */
608     fifo8_create(&s->tx_fifo, IBEX_SPI_HOST_TXFIFO_LEN);
609     fifo8_create(&s->rx_fifo, IBEX_SPI_HOST_RXFIFO_LEN);
610 }
611 
612 static void ibex_spi_host_init(Object *obj)
613 {
614     IbexSPIHostState *s = IBEX_SPI_HOST(obj);
615 
616     sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->host_err);
617     sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->event);
618 
619     memory_region_init_io(&s->mmio, obj, &ibex_spi_ops, s,
620                           TYPE_IBEX_SPI_HOST, 0x1000);
621     sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio);
622 }
623 
624 static void ibex_spi_host_class_init(ObjectClass *klass, void *data)
625 {
626     DeviceClass *dc = DEVICE_CLASS(klass);
627     dc->realize = ibex_spi_host_realize;
628     dc->reset = ibex_spi_host_reset;
629     dc->vmsd = &vmstate_ibex;
630     device_class_set_props(dc, ibex_spi_properties);
631 }
632 
633 static const TypeInfo ibex_spi_host_info = {
634     .name          = TYPE_IBEX_SPI_HOST,
635     .parent        = TYPE_SYS_BUS_DEVICE,
636     .instance_size = sizeof(IbexSPIHostState),
637     .instance_init = ibex_spi_host_init,
638     .class_init    = ibex_spi_host_class_init,
639 };
640 
641 static void ibex_spi_host_register_types(void)
642 {
643     type_register_static(&ibex_spi_host_info);
644 }
645 
646 type_init(ibex_spi_host_register_types)
647