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