1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27#include "qemu/osdep.h"
28#include "hw/sysbus.h"
29#include "sysemu/sysemu.h"
30#include "qemu/log.h"
31#include "qemu/fifo8.h"
32
33#include "hw/ssi/ssi.h"
34
35#ifdef XILINX_SPI_ERR_DEBUG
36#define DB_PRINT(...) do { \
37 fprintf(stderr, ": %s: ", __func__); \
38 fprintf(stderr, ## __VA_ARGS__); \
39 } while (0)
40#else
41 #define DB_PRINT(...)
42#endif
43
44#define R_DGIER (0x1c / 4)
45#define R_DGIER_IE (1 << 31)
46
47#define R_IPISR (0x20 / 4)
48#define IRQ_DRR_NOT_EMPTY (1 << (31 - 23))
49#define IRQ_DRR_OVERRUN (1 << (31 - 26))
50#define IRQ_DRR_FULL (1 << (31 - 27))
51#define IRQ_TX_FF_HALF_EMPTY (1 << 6)
52#define IRQ_DTR_UNDERRUN (1 << 3)
53#define IRQ_DTR_EMPTY (1 << (31 - 29))
54
55#define R_IPIER (0x28 / 4)
56#define R_SRR (0x40 / 4)
57#define R_SPICR (0x60 / 4)
58#define R_SPICR_TXFF_RST (1 << 5)
59#define R_SPICR_RXFF_RST (1 << 6)
60#define R_SPICR_MTI (1 << 8)
61
62#define R_SPISR (0x64 / 4)
63#define SR_TX_FULL (1 << 3)
64#define SR_TX_EMPTY (1 << 2)
65#define SR_RX_FULL (1 << 1)
66#define SR_RX_EMPTY (1 << 0)
67
68#define R_SPIDTR (0x68 / 4)
69#define R_SPIDRR (0x6C / 4)
70#define R_SPISSR (0x70 / 4)
71#define R_TX_FF_OCY (0x74 / 4)
72#define R_RX_FF_OCY (0x78 / 4)
73#define R_MAX (0x7C / 4)
74
75#define FIFO_CAPACITY 256
76
77#define TYPE_XILINX_SPI "xlnx.xps-spi"
78#define XILINX_SPI(obj) OBJECT_CHECK(XilinxSPI, (obj), TYPE_XILINX_SPI)
79
80typedef struct XilinxSPI {
81 SysBusDevice parent_obj;
82
83 MemoryRegion mmio;
84
85 qemu_irq irq;
86 int irqline;
87
88 uint8_t num_cs;
89 qemu_irq *cs_lines;
90
91 SSIBus *spi;
92
93 Fifo8 rx_fifo;
94 Fifo8 tx_fifo;
95
96 uint32_t regs[R_MAX];
97} XilinxSPI;
98
99static void txfifo_reset(XilinxSPI *s)
100{
101 fifo8_reset(&s->tx_fifo);
102
103 s->regs[R_SPISR] &= ~SR_TX_FULL;
104 s->regs[R_SPISR] |= SR_TX_EMPTY;
105}
106
107static void rxfifo_reset(XilinxSPI *s)
108{
109 fifo8_reset(&s->rx_fifo);
110
111 s->regs[R_SPISR] |= SR_RX_EMPTY;
112 s->regs[R_SPISR] &= ~SR_RX_FULL;
113}
114
115static void xlx_spi_update_cs(XilinxSPI *s)
116{
117 int i;
118
119 for (i = 0; i < s->num_cs; ++i) {
120 qemu_set_irq(s->cs_lines[i], !(~s->regs[R_SPISSR] & 1 << i));
121 }
122}
123
124static void xlx_spi_update_irq(XilinxSPI *s)
125{
126 uint32_t pending;
127
128 s->regs[R_IPISR] |=
129 (!fifo8_is_empty(&s->rx_fifo) ? IRQ_DRR_NOT_EMPTY : 0) |
130 (fifo8_is_full(&s->rx_fifo) ? IRQ_DRR_FULL : 0);
131
132 pending = s->regs[R_IPISR] & s->regs[R_IPIER];
133
134 pending = pending && (s->regs[R_DGIER] & R_DGIER_IE);
135 pending = !!pending;
136
137
138
139 if (pending != s->irqline) {
140 s->irqline = pending;
141 DB_PRINT("irq_change of state %d ISR:%x IER:%X\n",
142 pending, s->regs[R_IPISR], s->regs[R_IPIER]);
143 qemu_set_irq(s->irq, pending);
144 }
145
146}
147
148static void xlx_spi_do_reset(XilinxSPI *s)
149{
150 memset(s->regs, 0, sizeof s->regs);
151
152 rxfifo_reset(s);
153 txfifo_reset(s);
154
155 s->regs[R_SPISSR] = ~0;
156 xlx_spi_update_irq(s);
157 xlx_spi_update_cs(s);
158}
159
160static void xlx_spi_reset(DeviceState *d)
161{
162 xlx_spi_do_reset(XILINX_SPI(d));
163}
164
165static inline int spi_master_enabled(XilinxSPI *s)
166{
167 return !(s->regs[R_SPICR] & R_SPICR_MTI);
168}
169
170static void spi_flush_txfifo(XilinxSPI *s)
171{
172 uint32_t tx;
173 uint32_t rx;
174
175 while (!fifo8_is_empty(&s->tx_fifo)) {
176 tx = (uint32_t)fifo8_pop(&s->tx_fifo);
177 DB_PRINT("data tx:%x\n", tx);
178 rx = ssi_transfer(s->spi, tx);
179 DB_PRINT("data rx:%x\n", rx);
180 if (fifo8_is_full(&s->rx_fifo)) {
181 s->regs[R_IPISR] |= IRQ_DRR_OVERRUN;
182 } else {
183 fifo8_push(&s->rx_fifo, (uint8_t)rx);
184 if (fifo8_is_full(&s->rx_fifo)) {
185 s->regs[R_SPISR] |= SR_RX_FULL;
186 s->regs[R_IPISR] |= IRQ_DRR_FULL;
187 }
188 }
189
190 s->regs[R_SPISR] &= ~SR_RX_EMPTY;
191 s->regs[R_SPISR] &= ~SR_TX_FULL;
192 s->regs[R_SPISR] |= SR_TX_EMPTY;
193
194 s->regs[R_IPISR] |= IRQ_DTR_EMPTY;
195 s->regs[R_IPISR] |= IRQ_DRR_NOT_EMPTY;
196 }
197
198}
199
200static uint64_t
201spi_read(void *opaque, hwaddr addr, unsigned int size)
202{
203 XilinxSPI *s = opaque;
204 uint32_t r = 0;
205
206 addr >>= 2;
207 switch (addr) {
208 case R_SPIDRR:
209 if (fifo8_is_empty(&s->rx_fifo)) {
210 DB_PRINT("Read from empty FIFO!\n");
211 return 0xdeadbeef;
212 }
213
214 s->regs[R_SPISR] &= ~SR_RX_FULL;
215 r = fifo8_pop(&s->rx_fifo);
216 if (fifo8_is_empty(&s->rx_fifo)) {
217 s->regs[R_SPISR] |= SR_RX_EMPTY;
218 }
219 break;
220
221 case R_SPISR:
222 r = s->regs[addr];
223 break;
224
225 default:
226 if (addr < ARRAY_SIZE(s->regs)) {
227 r = s->regs[addr];
228 }
229 break;
230
231 }
232 DB_PRINT("addr=" TARGET_FMT_plx " = %x\n", addr * 4, r);
233 xlx_spi_update_irq(s);
234 return r;
235}
236
237static void
238spi_write(void *opaque, hwaddr addr,
239 uint64_t val64, unsigned int size)
240{
241 XilinxSPI *s = opaque;
242 uint32_t value = val64;
243
244 DB_PRINT("addr=" TARGET_FMT_plx " = %x\n", addr, value);
245 addr >>= 2;
246 switch (addr) {
247 case R_SRR:
248 if (value != 0xa) {
249 DB_PRINT("Invalid write to SRR %x\n", value);
250 } else {
251 xlx_spi_do_reset(s);
252 }
253 break;
254
255 case R_SPIDTR:
256 s->regs[R_SPISR] &= ~SR_TX_EMPTY;
257 fifo8_push(&s->tx_fifo, (uint8_t)value);
258 if (fifo8_is_full(&s->tx_fifo)) {
259 s->regs[R_SPISR] |= SR_TX_FULL;
260 }
261 if (!spi_master_enabled(s)) {
262 goto done;
263 } else {
264 DB_PRINT("DTR and master enabled\n");
265 }
266 spi_flush_txfifo(s);
267 break;
268
269 case R_SPISR:
270 DB_PRINT("Invalid write to SPISR %x\n", value);
271 break;
272
273 case R_IPISR:
274
275 s->regs[addr] ^= value;
276 break;
277
278
279 case R_SPISSR:
280 s->regs[addr] = value;
281 xlx_spi_update_cs(s);
282 break;
283
284 case R_SPICR:
285
286 if (value & R_SPICR_RXFF_RST) {
287 rxfifo_reset(s);
288 }
289
290 if (value & R_SPICR_TXFF_RST) {
291 txfifo_reset(s);
292 }
293 value &= ~(R_SPICR_RXFF_RST | R_SPICR_TXFF_RST);
294 s->regs[addr] = value;
295
296 if (!(value & R_SPICR_MTI)) {
297 spi_flush_txfifo(s);
298 }
299 break;
300
301 default:
302 if (addr < ARRAY_SIZE(s->regs)) {
303 s->regs[addr] = value;
304 }
305 break;
306 }
307
308done:
309 xlx_spi_update_irq(s);
310}
311
312static const MemoryRegionOps spi_ops = {
313 .read = spi_read,
314 .write = spi_write,
315 .endianness = DEVICE_NATIVE_ENDIAN,
316 .valid = {
317 .min_access_size = 4,
318 .max_access_size = 4
319 }
320};
321
322static int xilinx_spi_init(SysBusDevice *sbd)
323{
324 DeviceState *dev = DEVICE(sbd);
325 XilinxSPI *s = XILINX_SPI(dev);
326 int i;
327
328 DB_PRINT("\n");
329
330 s->spi = ssi_create_bus(dev, "spi");
331
332 sysbus_init_irq(sbd, &s->irq);
333 s->cs_lines = g_new0(qemu_irq, s->num_cs);
334 ssi_auto_connect_slaves(dev, s->cs_lines, s->spi);
335 for (i = 0; i < s->num_cs; ++i) {
336 sysbus_init_irq(sbd, &s->cs_lines[i]);
337 }
338
339 memory_region_init_io(&s->mmio, OBJECT(s), &spi_ops, s,
340 "xilinx-spi", R_MAX * 4);
341 sysbus_init_mmio(sbd, &s->mmio);
342
343 s->irqline = -1;
344
345 fifo8_create(&s->tx_fifo, FIFO_CAPACITY);
346 fifo8_create(&s->rx_fifo, FIFO_CAPACITY);
347
348 return 0;
349}
350
351static const VMStateDescription vmstate_xilinx_spi = {
352 .name = "xilinx_spi",
353 .version_id = 1,
354 .minimum_version_id = 1,
355 .fields = (VMStateField[]) {
356 VMSTATE_FIFO8(tx_fifo, XilinxSPI),
357 VMSTATE_FIFO8(rx_fifo, XilinxSPI),
358 VMSTATE_UINT32_ARRAY(regs, XilinxSPI, R_MAX),
359 VMSTATE_END_OF_LIST()
360 }
361};
362
363static Property xilinx_spi_properties[] = {
364 DEFINE_PROP_UINT8("num-ss-bits", XilinxSPI, num_cs, 1),
365 DEFINE_PROP_END_OF_LIST(),
366};
367
368static void xilinx_spi_class_init(ObjectClass *klass, void *data)
369{
370 DeviceClass *dc = DEVICE_CLASS(klass);
371 SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
372
373 k->init = xilinx_spi_init;
374 dc->reset = xlx_spi_reset;
375 dc->props = xilinx_spi_properties;
376 dc->vmsd = &vmstate_xilinx_spi;
377}
378
379static const TypeInfo xilinx_spi_info = {
380 .name = TYPE_XILINX_SPI,
381 .parent = TYPE_SYS_BUS_DEVICE,
382 .instance_size = sizeof(XilinxSPI),
383 .class_init = xilinx_spi_class_init,
384};
385
386static void xilinx_spi_register_types(void)
387{
388 type_register_static(&xilinx_spi_info);
389}
390
391type_init(xilinx_spi_register_types)
392
