1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Silvaco dual-role I3C master driver
4 *
5 * Copyright (C) 2020 Silvaco
6 * Author: Miquel RAYNAL <miquel.raynal@bootlin.com>
7 * Based on a work from: Conor Culhane <conor.culhane@silvaco.com>
8 */
9
10 #include <linux/bitfield.h>
11 #include <linux/clk.h>
12 #include <linux/completion.h>
13 #include <linux/errno.h>
14 #include <linux/i3c/master.h>
15 #include <linux/interrupt.h>
16 #include <linux/iopoll.h>
17 #include <linux/list.h>
18 #include <linux/module.h>
19 #include <linux/of.h>
20 #include <linux/pinctrl/consumer.h>
21 #include <linux/platform_device.h>
22 #include <linux/pm_runtime.h>
23
24 /* Master Mode Registers */
25 #define SVC_I3C_MCONFIG 0x000
26 #define SVC_I3C_MCONFIG_MASTER_EN BIT(0)
27 #define SVC_I3C_MCONFIG_DISTO(x) FIELD_PREP(BIT(3), (x))
28 #define SVC_I3C_MCONFIG_HKEEP(x) FIELD_PREP(GENMASK(5, 4), (x))
29 #define SVC_I3C_MCONFIG_ODSTOP(x) FIELD_PREP(BIT(6), (x))
30 #define SVC_I3C_MCONFIG_PPBAUD(x) FIELD_PREP(GENMASK(11, 8), (x))
31 #define SVC_I3C_MCONFIG_PPLOW(x) FIELD_PREP(GENMASK(15, 12), (x))
32 #define SVC_I3C_MCONFIG_ODBAUD(x) FIELD_PREP(GENMASK(23, 16), (x))
33 #define SVC_I3C_MCONFIG_ODHPP(x) FIELD_PREP(BIT(24), (x))
34 #define SVC_I3C_MCONFIG_SKEW(x) FIELD_PREP(GENMASK(27, 25), (x))
35 #define SVC_I3C_MCONFIG_I2CBAUD(x) FIELD_PREP(GENMASK(31, 28), (x))
36
37 #define SVC_I3C_MCTRL 0x084
38 #define SVC_I3C_MCTRL_REQUEST_MASK GENMASK(2, 0)
39 #define SVC_I3C_MCTRL_REQUEST_NONE 0
40 #define SVC_I3C_MCTRL_REQUEST_START_ADDR 1
41 #define SVC_I3C_MCTRL_REQUEST_STOP 2
42 #define SVC_I3C_MCTRL_REQUEST_IBI_ACKNACK 3
43 #define SVC_I3C_MCTRL_REQUEST_PROC_DAA 4
44 #define SVC_I3C_MCTRL_REQUEST_AUTO_IBI 7
45 #define SVC_I3C_MCTRL_TYPE_I3C 0
46 #define SVC_I3C_MCTRL_TYPE_I2C BIT(4)
47 #define SVC_I3C_MCTRL_IBIRESP_AUTO 0
48 #define SVC_I3C_MCTRL_IBIRESP_ACK_WITHOUT_BYTE 0
49 #define SVC_I3C_MCTRL_IBIRESP_ACK_WITH_BYTE BIT(7)
50 #define SVC_I3C_MCTRL_IBIRESP_NACK BIT(6)
51 #define SVC_I3C_MCTRL_IBIRESP_MANUAL GENMASK(7, 6)
52 #define SVC_I3C_MCTRL_DIR(x) FIELD_PREP(BIT(8), (x))
53 #define SVC_I3C_MCTRL_DIR_WRITE 0
54 #define SVC_I3C_MCTRL_DIR_READ 1
55 #define SVC_I3C_MCTRL_ADDR(x) FIELD_PREP(GENMASK(15, 9), (x))
56 #define SVC_I3C_MCTRL_RDTERM(x) FIELD_PREP(GENMASK(23, 16), (x))
57
58 #define SVC_I3C_MSTATUS 0x088
59 #define SVC_I3C_MSTATUS_STATE(x) FIELD_GET(GENMASK(2, 0), (x))
60 #define SVC_I3C_MSTATUS_STATE_DAA(x) (SVC_I3C_MSTATUS_STATE(x) == 5)
61 #define SVC_I3C_MSTATUS_STATE_IDLE(x) (SVC_I3C_MSTATUS_STATE(x) == 0)
62 #define SVC_I3C_MSTATUS_BETWEEN(x) FIELD_GET(BIT(4), (x))
63 #define SVC_I3C_MSTATUS_NACKED(x) FIELD_GET(BIT(5), (x))
64 #define SVC_I3C_MSTATUS_IBITYPE(x) FIELD_GET(GENMASK(7, 6), (x))
65 #define SVC_I3C_MSTATUS_IBITYPE_IBI 1
66 #define SVC_I3C_MSTATUS_IBITYPE_MASTER_REQUEST 2
67 #define SVC_I3C_MSTATUS_IBITYPE_HOT_JOIN 3
68 #define SVC_I3C_MINT_SLVSTART BIT(8)
69 #define SVC_I3C_MINT_MCTRLDONE BIT(9)
70 #define SVC_I3C_MINT_COMPLETE BIT(10)
71 #define SVC_I3C_MINT_RXPEND BIT(11)
72 #define SVC_I3C_MINT_TXNOTFULL BIT(12)
73 #define SVC_I3C_MINT_IBIWON BIT(13)
74 #define SVC_I3C_MINT_ERRWARN BIT(15)
75 #define SVC_I3C_MSTATUS_SLVSTART(x) FIELD_GET(SVC_I3C_MINT_SLVSTART, (x))
76 #define SVC_I3C_MSTATUS_MCTRLDONE(x) FIELD_GET(SVC_I3C_MINT_MCTRLDONE, (x))
77 #define SVC_I3C_MSTATUS_COMPLETE(x) FIELD_GET(SVC_I3C_MINT_COMPLETE, (x))
78 #define SVC_I3C_MSTATUS_RXPEND(x) FIELD_GET(SVC_I3C_MINT_RXPEND, (x))
79 #define SVC_I3C_MSTATUS_TXNOTFULL(x) FIELD_GET(SVC_I3C_MINT_TXNOTFULL, (x))
80 #define SVC_I3C_MSTATUS_IBIWON(x) FIELD_GET(SVC_I3C_MINT_IBIWON, (x))
81 #define SVC_I3C_MSTATUS_ERRWARN(x) FIELD_GET(SVC_I3C_MINT_ERRWARN, (x))
82 #define SVC_I3C_MSTATUS_IBIADDR(x) FIELD_GET(GENMASK(30, 24), (x))
83
84 #define SVC_I3C_IBIRULES 0x08C
85 #define SVC_I3C_IBIRULES_ADDR(slot, addr) FIELD_PREP(GENMASK(29, 0), \
86 ((addr) & 0x3F) << ((slot) * 6))
87 #define SVC_I3C_IBIRULES_ADDRS 5
88 #define SVC_I3C_IBIRULES_MSB0 BIT(30)
89 #define SVC_I3C_IBIRULES_NOBYTE BIT(31)
90 #define SVC_I3C_IBIRULES_MANDBYTE 0
91 #define SVC_I3C_MINTSET 0x090
92 #define SVC_I3C_MINTCLR 0x094
93 #define SVC_I3C_MINTMASKED 0x098
94 #define SVC_I3C_MERRWARN 0x09C
95 #define SVC_I3C_MDMACTRL 0x0A0
96 #define SVC_I3C_MDATACTRL 0x0AC
97 #define SVC_I3C_MDATACTRL_FLUSHTB BIT(0)
98 #define SVC_I3C_MDATACTRL_FLUSHRB BIT(1)
99 #define SVC_I3C_MDATACTRL_UNLOCK_TRIG BIT(3)
100 #define SVC_I3C_MDATACTRL_TXTRIG_FIFO_NOT_FULL GENMASK(5, 4)
101 #define SVC_I3C_MDATACTRL_RXTRIG_FIFO_NOT_EMPTY 0
102 #define SVC_I3C_MDATACTRL_RXCOUNT(x) FIELD_GET(GENMASK(28, 24), (x))
103 #define SVC_I3C_MDATACTRL_TXFULL BIT(30)
104 #define SVC_I3C_MDATACTRL_RXEMPTY BIT(31)
105
106 #define SVC_I3C_MWDATAB 0x0B0
107 #define SVC_I3C_MWDATAB_END BIT(8)
108
109 #define SVC_I3C_MWDATABE 0x0B4
110 #define SVC_I3C_MWDATAH 0x0B8
111 #define SVC_I3C_MWDATAHE 0x0BC
112 #define SVC_I3C_MRDATAB 0x0C0
113 #define SVC_I3C_MRDATAH 0x0C8
114 #define SVC_I3C_MWMSG_SDR 0x0D0
115 #define SVC_I3C_MRMSG_SDR 0x0D4
116 #define SVC_I3C_MWMSG_DDR 0x0D8
117 #define SVC_I3C_MRMSG_DDR 0x0DC
118
119 #define SVC_I3C_MDYNADDR 0x0E4
120 #define SVC_MDYNADDR_VALID BIT(0)
121 #define SVC_MDYNADDR_ADDR(x) FIELD_PREP(GENMASK(7, 1), (x))
122
123 #define SVC_I3C_MAX_DEVS 32
124 #define SVC_I3C_PM_TIMEOUT_MS 1000
125
126 /* This parameter depends on the implementation and may be tuned */
127 #define SVC_I3C_FIFO_SIZE 16
128
129 struct svc_i3c_cmd {
130 u8 addr;
131 bool rnw;
132 u8 *in;
133 const void *out;
134 unsigned int len;
135 unsigned int read_len;
136 bool continued;
137 };
138
139 struct svc_i3c_xfer {
140 struct list_head node;
141 struct completion comp;
142 int ret;
143 unsigned int type;
144 unsigned int ncmds;
145 struct svc_i3c_cmd cmds[];
146 };
147
148 /**
149 * struct svc_i3c_master - Silvaco I3C Master structure
150 * @base: I3C master controller
151 * @dev: Corresponding device
152 * @regs: Memory mapping
153 * @free_slots: Bit array of available slots
154 * @addrs: Array containing the dynamic addresses of each attached device
155 * @descs: Array of descriptors, one per attached device
156 * @hj_work: Hot-join work
157 * @ibi_work: IBI work
158 * @irq: Main interrupt
159 * @pclk: System clock
160 * @fclk: Fast clock (bus)
161 * @sclk: Slow clock (other events)
162 * @xferqueue: Transfer queue structure
163 * @xferqueue.list: List member
164 * @xferqueue.cur: Current ongoing transfer
165 * @xferqueue.lock: Queue lock
166 * @ibi: IBI structure
167 * @ibi.num_slots: Number of slots available in @ibi.slots
168 * @ibi.slots: Available IBI slots
169 * @ibi.tbq_slot: To be queued IBI slot
170 * @ibi.lock: IBI lock
171 */
172 struct svc_i3c_master {
173 struct i3c_master_controller base;
174 struct device *dev;
175 void __iomem *regs;
176 u32 free_slots;
177 u8 addrs[SVC_I3C_MAX_DEVS];
178 struct i3c_dev_desc *descs[SVC_I3C_MAX_DEVS];
179 struct work_struct hj_work;
180 struct work_struct ibi_work;
181 int irq;
182 struct clk *pclk;
183 struct clk *fclk;
184 struct clk *sclk;
185 struct {
186 struct list_head list;
187 struct svc_i3c_xfer *cur;
188 /* Prevent races between transfers */
189 spinlock_t lock;
190 } xferqueue;
191 struct {
192 unsigned int num_slots;
193 struct i3c_dev_desc **slots;
194 struct i3c_ibi_slot *tbq_slot;
195 /* Prevent races within IBI handlers */
196 spinlock_t lock;
197 } ibi;
198 };
199
200 /**
201 * struct svc_i3c_i2c_dev_data - Device specific data
202 * @index: Index in the master tables corresponding to this device
203 * @ibi: IBI slot index in the master structure
204 * @ibi_pool: IBI pool associated to this device
205 */
206 struct svc_i3c_i2c_dev_data {
207 u8 index;
208 int ibi;
209 struct i3c_generic_ibi_pool *ibi_pool;
210 };
211
svc_i3c_master_error(struct svc_i3c_master * master)212 static bool svc_i3c_master_error(struct svc_i3c_master *master)
213 {
214 u32 mstatus, merrwarn;
215
216 mstatus = readl(master->regs + SVC_I3C_MSTATUS);
217 if (SVC_I3C_MSTATUS_ERRWARN(mstatus)) {
218 merrwarn = readl(master->regs + SVC_I3C_MERRWARN);
219 writel(merrwarn, master->regs + SVC_I3C_MERRWARN);
220 dev_err(master->dev,
221 "Error condition: MSTATUS 0x%08x, MERRWARN 0x%08x\n",
222 mstatus, merrwarn);
223
224 return true;
225 }
226
227 return false;
228 }
229
svc_i3c_master_enable_interrupts(struct svc_i3c_master * master,u32 mask)230 static void svc_i3c_master_enable_interrupts(struct svc_i3c_master *master, u32 mask)
231 {
232 writel(mask, master->regs + SVC_I3C_MINTSET);
233 }
234
svc_i3c_master_disable_interrupts(struct svc_i3c_master * master)235 static void svc_i3c_master_disable_interrupts(struct svc_i3c_master *master)
236 {
237 u32 mask = readl(master->regs + SVC_I3C_MINTSET);
238
239 writel(mask, master->regs + SVC_I3C_MINTCLR);
240 }
241
svc_i3c_master_clear_merrwarn(struct svc_i3c_master * master)242 static void svc_i3c_master_clear_merrwarn(struct svc_i3c_master *master)
243 {
244 /* Clear pending warnings */
245 writel(readl(master->regs + SVC_I3C_MERRWARN),
246 master->regs + SVC_I3C_MERRWARN);
247 }
248
svc_i3c_master_flush_fifo(struct svc_i3c_master * master)249 static void svc_i3c_master_flush_fifo(struct svc_i3c_master *master)
250 {
251 /* Flush FIFOs */
252 writel(SVC_I3C_MDATACTRL_FLUSHTB | SVC_I3C_MDATACTRL_FLUSHRB,
253 master->regs + SVC_I3C_MDATACTRL);
254 }
255
svc_i3c_master_reset_fifo_trigger(struct svc_i3c_master * master)256 static void svc_i3c_master_reset_fifo_trigger(struct svc_i3c_master *master)
257 {
258 u32 reg;
259
260 /* Set RX and TX tigger levels, flush FIFOs */
261 reg = SVC_I3C_MDATACTRL_FLUSHTB |
262 SVC_I3C_MDATACTRL_FLUSHRB |
263 SVC_I3C_MDATACTRL_UNLOCK_TRIG |
264 SVC_I3C_MDATACTRL_TXTRIG_FIFO_NOT_FULL |
265 SVC_I3C_MDATACTRL_RXTRIG_FIFO_NOT_EMPTY;
266 writel(reg, master->regs + SVC_I3C_MDATACTRL);
267 }
268
svc_i3c_master_reset(struct svc_i3c_master * master)269 static void svc_i3c_master_reset(struct svc_i3c_master *master)
270 {
271 svc_i3c_master_clear_merrwarn(master);
272 svc_i3c_master_reset_fifo_trigger(master);
273 svc_i3c_master_disable_interrupts(master);
274 }
275
276 static inline struct svc_i3c_master *
to_svc_i3c_master(struct i3c_master_controller * master)277 to_svc_i3c_master(struct i3c_master_controller *master)
278 {
279 return container_of(master, struct svc_i3c_master, base);
280 }
281
svc_i3c_master_hj_work(struct work_struct * work)282 static void svc_i3c_master_hj_work(struct work_struct *work)
283 {
284 struct svc_i3c_master *master;
285
286 master = container_of(work, struct svc_i3c_master, hj_work);
287 i3c_master_do_daa(&master->base);
288 }
289
290 static struct i3c_dev_desc *
svc_i3c_master_dev_from_addr(struct svc_i3c_master * master,unsigned int ibiaddr)291 svc_i3c_master_dev_from_addr(struct svc_i3c_master *master,
292 unsigned int ibiaddr)
293 {
294 int i;
295
296 for (i = 0; i < SVC_I3C_MAX_DEVS; i++)
297 if (master->addrs[i] == ibiaddr)
298 break;
299
300 if (i == SVC_I3C_MAX_DEVS)
301 return NULL;
302
303 return master->descs[i];
304 }
305
svc_i3c_master_emit_stop(struct svc_i3c_master * master)306 static void svc_i3c_master_emit_stop(struct svc_i3c_master *master)
307 {
308 writel(SVC_I3C_MCTRL_REQUEST_STOP, master->regs + SVC_I3C_MCTRL);
309
310 /*
311 * This delay is necessary after the emission of a stop, otherwise eg.
312 * repeating IBIs do not get detected. There is a note in the manual
313 * about it, stating that the stop condition might not be settled
314 * correctly if a start condition follows too rapidly.
315 */
316 udelay(1);
317 }
318
svc_i3c_master_handle_ibi(struct svc_i3c_master * master,struct i3c_dev_desc * dev)319 static int svc_i3c_master_handle_ibi(struct svc_i3c_master *master,
320 struct i3c_dev_desc *dev)
321 {
322 struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
323 struct i3c_ibi_slot *slot;
324 unsigned int count;
325 u32 mdatactrl;
326 u8 *buf;
327
328 slot = i3c_generic_ibi_get_free_slot(data->ibi_pool);
329 if (!slot)
330 return -ENOSPC;
331
332 slot->len = 0;
333 buf = slot->data;
334
335 while (SVC_I3C_MSTATUS_RXPEND(readl(master->regs + SVC_I3C_MSTATUS)) &&
336 slot->len < SVC_I3C_FIFO_SIZE) {
337 mdatactrl = readl(master->regs + SVC_I3C_MDATACTRL);
338 count = SVC_I3C_MDATACTRL_RXCOUNT(mdatactrl);
339 readsl(master->regs + SVC_I3C_MRDATAB, buf, count);
340 slot->len += count;
341 buf += count;
342 }
343
344 master->ibi.tbq_slot = slot;
345
346 return 0;
347 }
348
svc_i3c_master_ack_ibi(struct svc_i3c_master * master,bool mandatory_byte)349 static void svc_i3c_master_ack_ibi(struct svc_i3c_master *master,
350 bool mandatory_byte)
351 {
352 unsigned int ibi_ack_nack;
353
354 ibi_ack_nack = SVC_I3C_MCTRL_REQUEST_IBI_ACKNACK;
355 if (mandatory_byte)
356 ibi_ack_nack |= SVC_I3C_MCTRL_IBIRESP_ACK_WITH_BYTE;
357 else
358 ibi_ack_nack |= SVC_I3C_MCTRL_IBIRESP_ACK_WITHOUT_BYTE;
359
360 writel(ibi_ack_nack, master->regs + SVC_I3C_MCTRL);
361 }
362
svc_i3c_master_nack_ibi(struct svc_i3c_master * master)363 static void svc_i3c_master_nack_ibi(struct svc_i3c_master *master)
364 {
365 writel(SVC_I3C_MCTRL_REQUEST_IBI_ACKNACK |
366 SVC_I3C_MCTRL_IBIRESP_NACK,
367 master->regs + SVC_I3C_MCTRL);
368 }
369
svc_i3c_master_ibi_work(struct work_struct * work)370 static void svc_i3c_master_ibi_work(struct work_struct *work)
371 {
372 struct svc_i3c_master *master = container_of(work, struct svc_i3c_master, ibi_work);
373 struct svc_i3c_i2c_dev_data *data;
374 unsigned int ibitype, ibiaddr;
375 struct i3c_dev_desc *dev;
376 u32 status, val;
377 int ret;
378
379 /* Acknowledge the incoming interrupt with the AUTOIBI mechanism */
380 writel(SVC_I3C_MCTRL_REQUEST_AUTO_IBI |
381 SVC_I3C_MCTRL_IBIRESP_AUTO,
382 master->regs + SVC_I3C_MCTRL);
383
384 /* Wait for IBIWON, should take approximately 100us */
385 ret = readl_relaxed_poll_timeout(master->regs + SVC_I3C_MSTATUS, val,
386 SVC_I3C_MSTATUS_IBIWON(val), 0, 1000);
387 if (ret) {
388 dev_err(master->dev, "Timeout when polling for IBIWON\n");
389 goto reenable_ibis;
390 }
391
392 /* Clear the interrupt status */
393 writel(SVC_I3C_MINT_IBIWON, master->regs + SVC_I3C_MSTATUS);
394
395 status = readl(master->regs + SVC_I3C_MSTATUS);
396 ibitype = SVC_I3C_MSTATUS_IBITYPE(status);
397 ibiaddr = SVC_I3C_MSTATUS_IBIADDR(status);
398
399 /* Handle the critical responses to IBI's */
400 switch (ibitype) {
401 case SVC_I3C_MSTATUS_IBITYPE_IBI:
402 dev = svc_i3c_master_dev_from_addr(master, ibiaddr);
403 if (!dev)
404 svc_i3c_master_nack_ibi(master);
405 else
406 svc_i3c_master_handle_ibi(master, dev);
407 break;
408 case SVC_I3C_MSTATUS_IBITYPE_HOT_JOIN:
409 svc_i3c_master_ack_ibi(master, false);
410 break;
411 case SVC_I3C_MSTATUS_IBITYPE_MASTER_REQUEST:
412 svc_i3c_master_nack_ibi(master);
413 break;
414 default:
415 break;
416 }
417
418 /*
419 * If an error happened, we probably got interrupted and the exchange
420 * timedout. In this case we just drop everything, emit a stop and wait
421 * for the slave to interrupt again.
422 */
423 if (svc_i3c_master_error(master)) {
424 if (master->ibi.tbq_slot) {
425 data = i3c_dev_get_master_data(dev);
426 i3c_generic_ibi_recycle_slot(data->ibi_pool,
427 master->ibi.tbq_slot);
428 master->ibi.tbq_slot = NULL;
429 }
430
431 svc_i3c_master_emit_stop(master);
432
433 goto reenable_ibis;
434 }
435
436 /* Handle the non critical tasks */
437 switch (ibitype) {
438 case SVC_I3C_MSTATUS_IBITYPE_IBI:
439 if (dev) {
440 i3c_master_queue_ibi(dev, master->ibi.tbq_slot);
441 master->ibi.tbq_slot = NULL;
442 }
443 svc_i3c_master_emit_stop(master);
444 break;
445 case SVC_I3C_MSTATUS_IBITYPE_HOT_JOIN:
446 queue_work(master->base.wq, &master->hj_work);
447 break;
448 case SVC_I3C_MSTATUS_IBITYPE_MASTER_REQUEST:
449 default:
450 break;
451 }
452
453 reenable_ibis:
454 svc_i3c_master_enable_interrupts(master, SVC_I3C_MINT_SLVSTART);
455 }
456
svc_i3c_master_irq_handler(int irq,void * dev_id)457 static irqreturn_t svc_i3c_master_irq_handler(int irq, void *dev_id)
458 {
459 struct svc_i3c_master *master = (struct svc_i3c_master *)dev_id;
460 u32 active = readl(master->regs + SVC_I3C_MINTMASKED);
461
462 if (!SVC_I3C_MSTATUS_SLVSTART(active))
463 return IRQ_NONE;
464
465 /* Clear the interrupt status */
466 writel(SVC_I3C_MINT_SLVSTART, master->regs + SVC_I3C_MSTATUS);
467
468 svc_i3c_master_disable_interrupts(master);
469
470 /* Handle the interrupt in a non atomic context */
471 queue_work(master->base.wq, &master->ibi_work);
472
473 return IRQ_HANDLED;
474 }
475
svc_i3c_master_bus_init(struct i3c_master_controller * m)476 static int svc_i3c_master_bus_init(struct i3c_master_controller *m)
477 {
478 struct svc_i3c_master *master = to_svc_i3c_master(m);
479 struct i3c_bus *bus = i3c_master_get_bus(m);
480 struct i3c_device_info info = {};
481 unsigned long fclk_rate, fclk_period_ns;
482 unsigned int high_period_ns, od_low_period_ns;
483 u32 ppbaud, pplow, odhpp, odbaud, odstop, i2cbaud, reg;
484 int ret;
485
486 ret = pm_runtime_resume_and_get(master->dev);
487 if (ret < 0) {
488 dev_err(master->dev,
489 "<%s> cannot resume i3c bus master, err: %d\n",
490 __func__, ret);
491 return ret;
492 }
493
494 /* Timings derivation */
495 fclk_rate = clk_get_rate(master->fclk);
496 if (!fclk_rate) {
497 ret = -EINVAL;
498 goto rpm_out;
499 }
500
501 fclk_period_ns = DIV_ROUND_UP(1000000000, fclk_rate);
502
503 /*
504 * Using I3C Push-Pull mode, target is 12.5MHz/80ns period.
505 * Simplest configuration is using a 50% duty-cycle of 40ns.
506 */
507 ppbaud = DIV_ROUND_UP(40, fclk_period_ns) - 1;
508 pplow = 0;
509
510 /*
511 * Using I3C Open-Drain mode, target is 4.17MHz/240ns with a
512 * duty-cycle tuned so that high levels are filetered out by
513 * the 50ns filter (target being 40ns).
514 */
515 odhpp = 1;
516 high_period_ns = (ppbaud + 1) * fclk_period_ns;
517 odbaud = DIV_ROUND_UP(240 - high_period_ns, high_period_ns) - 1;
518 od_low_period_ns = (odbaud + 1) * high_period_ns;
519
520 switch (bus->mode) {
521 case I3C_BUS_MODE_PURE:
522 i2cbaud = 0;
523 odstop = 0;
524 break;
525 case I3C_BUS_MODE_MIXED_FAST:
526 case I3C_BUS_MODE_MIXED_LIMITED:
527 /*
528 * Using I2C Fm+ mode, target is 1MHz/1000ns, the difference
529 * between the high and low period does not really matter.
530 */
531 i2cbaud = DIV_ROUND_UP(1000, od_low_period_ns) - 2;
532 odstop = 1;
533 break;
534 case I3C_BUS_MODE_MIXED_SLOW:
535 /*
536 * Using I2C Fm mode, target is 0.4MHz/2500ns, with the same
537 * constraints as the FM+ mode.
538 */
539 i2cbaud = DIV_ROUND_UP(2500, od_low_period_ns) - 2;
540 odstop = 1;
541 break;
542 default:
543 goto rpm_out;
544 }
545
546 reg = SVC_I3C_MCONFIG_MASTER_EN |
547 SVC_I3C_MCONFIG_DISTO(0) |
548 SVC_I3C_MCONFIG_HKEEP(0) |
549 SVC_I3C_MCONFIG_ODSTOP(odstop) |
550 SVC_I3C_MCONFIG_PPBAUD(ppbaud) |
551 SVC_I3C_MCONFIG_PPLOW(pplow) |
552 SVC_I3C_MCONFIG_ODBAUD(odbaud) |
553 SVC_I3C_MCONFIG_ODHPP(odhpp) |
554 SVC_I3C_MCONFIG_SKEW(0) |
555 SVC_I3C_MCONFIG_I2CBAUD(i2cbaud);
556 writel(reg, master->regs + SVC_I3C_MCONFIG);
557
558 /* Master core's registration */
559 ret = i3c_master_get_free_addr(m, 0);
560 if (ret < 0)
561 goto rpm_out;
562
563 info.dyn_addr = ret;
564
565 writel(SVC_MDYNADDR_VALID | SVC_MDYNADDR_ADDR(info.dyn_addr),
566 master->regs + SVC_I3C_MDYNADDR);
567
568 ret = i3c_master_set_info(&master->base, &info);
569 if (ret)
570 goto rpm_out;
571
572 rpm_out:
573 pm_runtime_mark_last_busy(master->dev);
574 pm_runtime_put_autosuspend(master->dev);
575
576 return ret;
577 }
578
svc_i3c_master_bus_cleanup(struct i3c_master_controller * m)579 static void svc_i3c_master_bus_cleanup(struct i3c_master_controller *m)
580 {
581 struct svc_i3c_master *master = to_svc_i3c_master(m);
582 int ret;
583
584 ret = pm_runtime_resume_and_get(master->dev);
585 if (ret < 0) {
586 dev_err(master->dev, "<%s> Cannot get runtime PM.\n", __func__);
587 return;
588 }
589
590 svc_i3c_master_disable_interrupts(master);
591
592 /* Disable master */
593 writel(0, master->regs + SVC_I3C_MCONFIG);
594
595 pm_runtime_mark_last_busy(master->dev);
596 pm_runtime_put_autosuspend(master->dev);
597 }
598
svc_i3c_master_reserve_slot(struct svc_i3c_master * master)599 static int svc_i3c_master_reserve_slot(struct svc_i3c_master *master)
600 {
601 unsigned int slot;
602
603 if (!(master->free_slots & GENMASK(SVC_I3C_MAX_DEVS - 1, 0)))
604 return -ENOSPC;
605
606 slot = ffs(master->free_slots) - 1;
607
608 master->free_slots &= ~BIT(slot);
609
610 return slot;
611 }
612
svc_i3c_master_release_slot(struct svc_i3c_master * master,unsigned int slot)613 static void svc_i3c_master_release_slot(struct svc_i3c_master *master,
614 unsigned int slot)
615 {
616 master->free_slots |= BIT(slot);
617 }
618
svc_i3c_master_attach_i3c_dev(struct i3c_dev_desc * dev)619 static int svc_i3c_master_attach_i3c_dev(struct i3c_dev_desc *dev)
620 {
621 struct i3c_master_controller *m = i3c_dev_get_master(dev);
622 struct svc_i3c_master *master = to_svc_i3c_master(m);
623 struct svc_i3c_i2c_dev_data *data;
624 int slot;
625
626 slot = svc_i3c_master_reserve_slot(master);
627 if (slot < 0)
628 return slot;
629
630 data = kzalloc(sizeof(*data), GFP_KERNEL);
631 if (!data) {
632 svc_i3c_master_release_slot(master, slot);
633 return -ENOMEM;
634 }
635
636 data->ibi = -1;
637 data->index = slot;
638 master->addrs[slot] = dev->info.dyn_addr ? dev->info.dyn_addr :
639 dev->info.static_addr;
640 master->descs[slot] = dev;
641
642 i3c_dev_set_master_data(dev, data);
643
644 return 0;
645 }
646
svc_i3c_master_reattach_i3c_dev(struct i3c_dev_desc * dev,u8 old_dyn_addr)647 static int svc_i3c_master_reattach_i3c_dev(struct i3c_dev_desc *dev,
648 u8 old_dyn_addr)
649 {
650 struct i3c_master_controller *m = i3c_dev_get_master(dev);
651 struct svc_i3c_master *master = to_svc_i3c_master(m);
652 struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
653
654 master->addrs[data->index] = dev->info.dyn_addr ? dev->info.dyn_addr :
655 dev->info.static_addr;
656
657 return 0;
658 }
659
svc_i3c_master_detach_i3c_dev(struct i3c_dev_desc * dev)660 static void svc_i3c_master_detach_i3c_dev(struct i3c_dev_desc *dev)
661 {
662 struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
663 struct i3c_master_controller *m = i3c_dev_get_master(dev);
664 struct svc_i3c_master *master = to_svc_i3c_master(m);
665
666 master->addrs[data->index] = 0;
667 svc_i3c_master_release_slot(master, data->index);
668
669 kfree(data);
670 }
671
svc_i3c_master_attach_i2c_dev(struct i2c_dev_desc * dev)672 static int svc_i3c_master_attach_i2c_dev(struct i2c_dev_desc *dev)
673 {
674 struct i3c_master_controller *m = i2c_dev_get_master(dev);
675 struct svc_i3c_master *master = to_svc_i3c_master(m);
676 struct svc_i3c_i2c_dev_data *data;
677 int slot;
678
679 slot = svc_i3c_master_reserve_slot(master);
680 if (slot < 0)
681 return slot;
682
683 data = kzalloc(sizeof(*data), GFP_KERNEL);
684 if (!data) {
685 svc_i3c_master_release_slot(master, slot);
686 return -ENOMEM;
687 }
688
689 data->index = slot;
690 master->addrs[slot] = dev->addr;
691
692 i2c_dev_set_master_data(dev, data);
693
694 return 0;
695 }
696
svc_i3c_master_detach_i2c_dev(struct i2c_dev_desc * dev)697 static void svc_i3c_master_detach_i2c_dev(struct i2c_dev_desc *dev)
698 {
699 struct svc_i3c_i2c_dev_data *data = i2c_dev_get_master_data(dev);
700 struct i3c_master_controller *m = i2c_dev_get_master(dev);
701 struct svc_i3c_master *master = to_svc_i3c_master(m);
702
703 svc_i3c_master_release_slot(master, data->index);
704
705 kfree(data);
706 }
707
svc_i3c_master_readb(struct svc_i3c_master * master,u8 * dst,unsigned int len)708 static int svc_i3c_master_readb(struct svc_i3c_master *master, u8 *dst,
709 unsigned int len)
710 {
711 int ret, i;
712 u32 reg;
713
714 for (i = 0; i < len; i++) {
715 ret = readl_poll_timeout_atomic(master->regs + SVC_I3C_MSTATUS,
716 reg,
717 SVC_I3C_MSTATUS_RXPEND(reg),
718 0, 1000);
719 if (ret)
720 return ret;
721
722 dst[i] = readl(master->regs + SVC_I3C_MRDATAB);
723 }
724
725 return 0;
726 }
727
svc_i3c_master_do_daa_locked(struct svc_i3c_master * master,u8 * addrs,unsigned int * count)728 static int svc_i3c_master_do_daa_locked(struct svc_i3c_master *master,
729 u8 *addrs, unsigned int *count)
730 {
731 u64 prov_id[SVC_I3C_MAX_DEVS] = {}, nacking_prov_id = 0;
732 unsigned int dev_nb = 0, last_addr = 0;
733 u32 reg;
734 int ret, i;
735
736 while (true) {
737 /* Enter/proceed with DAA */
738 writel(SVC_I3C_MCTRL_REQUEST_PROC_DAA |
739 SVC_I3C_MCTRL_TYPE_I3C |
740 SVC_I3C_MCTRL_IBIRESP_NACK |
741 SVC_I3C_MCTRL_DIR(SVC_I3C_MCTRL_DIR_WRITE),
742 master->regs + SVC_I3C_MCTRL);
743
744 /*
745 * Either one slave will send its ID, or the assignment process
746 * is done.
747 */
748 ret = readl_poll_timeout_atomic(master->regs + SVC_I3C_MSTATUS,
749 reg,
750 SVC_I3C_MSTATUS_RXPEND(reg) |
751 SVC_I3C_MSTATUS_MCTRLDONE(reg),
752 1, 1000);
753 if (ret)
754 return ret;
755
756 if (SVC_I3C_MSTATUS_RXPEND(reg)) {
757 u8 data[6];
758
759 /*
760 * We only care about the 48-bit provisional ID yet to
761 * be sure a device does not nack an address twice.
762 * Otherwise, we would just need to flush the RX FIFO.
763 */
764 ret = svc_i3c_master_readb(master, data, 6);
765 if (ret)
766 return ret;
767
768 for (i = 0; i < 6; i++)
769 prov_id[dev_nb] |= (u64)(data[i]) << (8 * (5 - i));
770
771 /* We do not care about the BCR and DCR yet */
772 ret = svc_i3c_master_readb(master, data, 2);
773 if (ret)
774 return ret;
775 } else if (SVC_I3C_MSTATUS_MCTRLDONE(reg)) {
776 if (SVC_I3C_MSTATUS_STATE_IDLE(reg) &&
777 SVC_I3C_MSTATUS_COMPLETE(reg)) {
778 /*
779 * All devices received and acked they dynamic
780 * address, this is the natural end of the DAA
781 * procedure.
782 */
783 break;
784 } else if (SVC_I3C_MSTATUS_NACKED(reg)) {
785 /*
786 * A slave device nacked the address, this is
787 * allowed only once, DAA will be stopped and
788 * then resumed. The same device is supposed to
789 * answer again immediately and shall ack the
790 * address this time.
791 */
792 if (prov_id[dev_nb] == nacking_prov_id)
793 return -EIO;
794
795 dev_nb--;
796 nacking_prov_id = prov_id[dev_nb];
797 svc_i3c_master_emit_stop(master);
798
799 continue;
800 } else {
801 return -EIO;
802 }
803 }
804
805 /* Wait for the slave to be ready to receive its address */
806 ret = readl_poll_timeout_atomic(master->regs + SVC_I3C_MSTATUS,
807 reg,
808 SVC_I3C_MSTATUS_MCTRLDONE(reg) &&
809 SVC_I3C_MSTATUS_STATE_DAA(reg) &&
810 SVC_I3C_MSTATUS_BETWEEN(reg),
811 0, 1000);
812 if (ret)
813 return ret;
814
815 /* Give the slave device a suitable dynamic address */
816 ret = i3c_master_get_free_addr(&master->base, last_addr + 1);
817 if (ret < 0)
818 return ret;
819
820 addrs[dev_nb] = ret;
821 dev_dbg(master->dev, "DAA: device %d assigned to 0x%02x\n",
822 dev_nb, addrs[dev_nb]);
823
824 writel(addrs[dev_nb], master->regs + SVC_I3C_MWDATAB);
825 last_addr = addrs[dev_nb++];
826 }
827
828 *count = dev_nb;
829
830 return 0;
831 }
832
svc_i3c_update_ibirules(struct svc_i3c_master * master)833 static int svc_i3c_update_ibirules(struct svc_i3c_master *master)
834 {
835 struct i3c_dev_desc *dev;
836 u32 reg_mbyte = 0, reg_nobyte = SVC_I3C_IBIRULES_NOBYTE;
837 unsigned int mbyte_addr_ok = 0, mbyte_addr_ko = 0, nobyte_addr_ok = 0,
838 nobyte_addr_ko = 0;
839 bool list_mbyte = false, list_nobyte = false;
840
841 /* Create the IBIRULES register for both cases */
842 i3c_bus_for_each_i3cdev(&master->base.bus, dev) {
843 if (I3C_BCR_DEVICE_ROLE(dev->info.bcr) == I3C_BCR_I3C_MASTER)
844 continue;
845
846 if (dev->info.bcr & I3C_BCR_IBI_PAYLOAD) {
847 reg_mbyte |= SVC_I3C_IBIRULES_ADDR(mbyte_addr_ok,
848 dev->info.dyn_addr);
849
850 /* IBI rules cannot be applied to devices with MSb=1 */
851 if (dev->info.dyn_addr & BIT(7))
852 mbyte_addr_ko++;
853 else
854 mbyte_addr_ok++;
855 } else {
856 reg_nobyte |= SVC_I3C_IBIRULES_ADDR(nobyte_addr_ok,
857 dev->info.dyn_addr);
858
859 /* IBI rules cannot be applied to devices with MSb=1 */
860 if (dev->info.dyn_addr & BIT(7))
861 nobyte_addr_ko++;
862 else
863 nobyte_addr_ok++;
864 }
865 }
866
867 /* Device list cannot be handled by hardware */
868 if (!mbyte_addr_ko && mbyte_addr_ok <= SVC_I3C_IBIRULES_ADDRS)
869 list_mbyte = true;
870
871 if (!nobyte_addr_ko && nobyte_addr_ok <= SVC_I3C_IBIRULES_ADDRS)
872 list_nobyte = true;
873
874 /* No list can be properly handled, return an error */
875 if (!list_mbyte && !list_nobyte)
876 return -ERANGE;
877
878 /* Pick the first list that can be handled by hardware, randomly */
879 if (list_mbyte)
880 writel(reg_mbyte, master->regs + SVC_I3C_IBIRULES);
881 else
882 writel(reg_nobyte, master->regs + SVC_I3C_IBIRULES);
883
884 return 0;
885 }
886
svc_i3c_master_do_daa(struct i3c_master_controller * m)887 static int svc_i3c_master_do_daa(struct i3c_master_controller *m)
888 {
889 struct svc_i3c_master *master = to_svc_i3c_master(m);
890 u8 addrs[SVC_I3C_MAX_DEVS];
891 unsigned long flags;
892 unsigned int dev_nb;
893 int ret, i;
894
895 ret = pm_runtime_resume_and_get(master->dev);
896 if (ret < 0) {
897 dev_err(master->dev, "<%s> Cannot get runtime PM.\n", __func__);
898 return ret;
899 }
900
901 spin_lock_irqsave(&master->xferqueue.lock, flags);
902 ret = svc_i3c_master_do_daa_locked(master, addrs, &dev_nb);
903 spin_unlock_irqrestore(&master->xferqueue.lock, flags);
904 if (ret) {
905 svc_i3c_master_emit_stop(master);
906 svc_i3c_master_clear_merrwarn(master);
907 goto rpm_out;
908 }
909
910 /* Register all devices who participated to the core */
911 for (i = 0; i < dev_nb; i++) {
912 ret = i3c_master_add_i3c_dev_locked(m, addrs[i]);
913 if (ret)
914 goto rpm_out;
915 }
916
917 /* Configure IBI auto-rules */
918 ret = svc_i3c_update_ibirules(master);
919 if (ret)
920 dev_err(master->dev, "Cannot handle such a list of devices");
921
922 rpm_out:
923 pm_runtime_mark_last_busy(master->dev);
924 pm_runtime_put_autosuspend(master->dev);
925
926 return ret;
927 }
928
svc_i3c_master_read(struct svc_i3c_master * master,u8 * in,unsigned int len)929 static int svc_i3c_master_read(struct svc_i3c_master *master,
930 u8 *in, unsigned int len)
931 {
932 int offset = 0, i;
933 u32 mdctrl, mstatus;
934 bool completed = false;
935 unsigned int count;
936 unsigned long start = jiffies;
937
938 while (!completed) {
939 mstatus = readl(master->regs + SVC_I3C_MSTATUS);
940 if (SVC_I3C_MSTATUS_COMPLETE(mstatus) != 0)
941 completed = true;
942
943 if (time_after(jiffies, start + msecs_to_jiffies(1000))) {
944 dev_dbg(master->dev, "I3C read timeout\n");
945 return -ETIMEDOUT;
946 }
947
948 mdctrl = readl(master->regs + SVC_I3C_MDATACTRL);
949 count = SVC_I3C_MDATACTRL_RXCOUNT(mdctrl);
950 if (offset + count > len) {
951 dev_err(master->dev, "I3C receive length too long!\n");
952 return -EINVAL;
953 }
954 for (i = 0; i < count; i++)
955 in[offset + i] = readl(master->regs + SVC_I3C_MRDATAB);
956
957 offset += count;
958 }
959
960 return offset;
961 }
962
svc_i3c_master_write(struct svc_i3c_master * master,const u8 * out,unsigned int len)963 static int svc_i3c_master_write(struct svc_i3c_master *master,
964 const u8 *out, unsigned int len)
965 {
966 int offset = 0, ret;
967 u32 mdctrl;
968
969 while (offset < len) {
970 ret = readl_poll_timeout(master->regs + SVC_I3C_MDATACTRL,
971 mdctrl,
972 !(mdctrl & SVC_I3C_MDATACTRL_TXFULL),
973 0, 1000);
974 if (ret)
975 return ret;
976
977 /*
978 * The last byte to be sent over the bus must either have the
979 * "end" bit set or be written in MWDATABE.
980 */
981 if (likely(offset < (len - 1)))
982 writel(out[offset++], master->regs + SVC_I3C_MWDATAB);
983 else
984 writel(out[offset++], master->regs + SVC_I3C_MWDATABE);
985 }
986
987 return 0;
988 }
989
svc_i3c_master_xfer(struct svc_i3c_master * master,bool rnw,unsigned int xfer_type,u8 addr,u8 * in,const u8 * out,unsigned int xfer_len,unsigned int * read_len,bool continued)990 static int svc_i3c_master_xfer(struct svc_i3c_master *master,
991 bool rnw, unsigned int xfer_type, u8 addr,
992 u8 *in, const u8 *out, unsigned int xfer_len,
993 unsigned int *read_len, bool continued)
994 {
995 u32 reg;
996 int ret;
997
998 writel(SVC_I3C_MCTRL_REQUEST_START_ADDR |
999 xfer_type |
1000 SVC_I3C_MCTRL_IBIRESP_NACK |
1001 SVC_I3C_MCTRL_DIR(rnw) |
1002 SVC_I3C_MCTRL_ADDR(addr) |
1003 SVC_I3C_MCTRL_RDTERM(*read_len),
1004 master->regs + SVC_I3C_MCTRL);
1005
1006 ret = readl_poll_timeout(master->regs + SVC_I3C_MSTATUS, reg,
1007 SVC_I3C_MSTATUS_MCTRLDONE(reg), 0, 1000);
1008 if (ret)
1009 goto emit_stop;
1010
1011 if (rnw)
1012 ret = svc_i3c_master_read(master, in, xfer_len);
1013 else
1014 ret = svc_i3c_master_write(master, out, xfer_len);
1015 if (ret < 0)
1016 goto emit_stop;
1017
1018 if (rnw)
1019 *read_len = ret;
1020
1021 ret = readl_poll_timeout(master->regs + SVC_I3C_MSTATUS, reg,
1022 SVC_I3C_MSTATUS_COMPLETE(reg), 0, 1000);
1023 if (ret)
1024 goto emit_stop;
1025
1026 writel(SVC_I3C_MINT_COMPLETE, master->regs + SVC_I3C_MSTATUS);
1027
1028 if (!continued) {
1029 svc_i3c_master_emit_stop(master);
1030
1031 /* Wait idle if stop is sent. */
1032 readl_poll_timeout(master->regs + SVC_I3C_MSTATUS, reg,
1033 SVC_I3C_MSTATUS_STATE_IDLE(reg), 0, 1000);
1034 }
1035
1036 return 0;
1037
1038 emit_stop:
1039 svc_i3c_master_emit_stop(master);
1040 svc_i3c_master_clear_merrwarn(master);
1041
1042 return ret;
1043 }
1044
1045 static struct svc_i3c_xfer *
svc_i3c_master_alloc_xfer(struct svc_i3c_master * master,unsigned int ncmds)1046 svc_i3c_master_alloc_xfer(struct svc_i3c_master *master, unsigned int ncmds)
1047 {
1048 struct svc_i3c_xfer *xfer;
1049
1050 xfer = kzalloc(struct_size(xfer, cmds, ncmds), GFP_KERNEL);
1051 if (!xfer)
1052 return NULL;
1053
1054 INIT_LIST_HEAD(&xfer->node);
1055 xfer->ncmds = ncmds;
1056 xfer->ret = -ETIMEDOUT;
1057
1058 return xfer;
1059 }
1060
svc_i3c_master_free_xfer(struct svc_i3c_xfer * xfer)1061 static void svc_i3c_master_free_xfer(struct svc_i3c_xfer *xfer)
1062 {
1063 kfree(xfer);
1064 }
1065
svc_i3c_master_dequeue_xfer_locked(struct svc_i3c_master * master,struct svc_i3c_xfer * xfer)1066 static void svc_i3c_master_dequeue_xfer_locked(struct svc_i3c_master *master,
1067 struct svc_i3c_xfer *xfer)
1068 {
1069 if (master->xferqueue.cur == xfer)
1070 master->xferqueue.cur = NULL;
1071 else
1072 list_del_init(&xfer->node);
1073 }
1074
svc_i3c_master_dequeue_xfer(struct svc_i3c_master * master,struct svc_i3c_xfer * xfer)1075 static void svc_i3c_master_dequeue_xfer(struct svc_i3c_master *master,
1076 struct svc_i3c_xfer *xfer)
1077 {
1078 unsigned long flags;
1079
1080 spin_lock_irqsave(&master->xferqueue.lock, flags);
1081 svc_i3c_master_dequeue_xfer_locked(master, xfer);
1082 spin_unlock_irqrestore(&master->xferqueue.lock, flags);
1083 }
1084
svc_i3c_master_start_xfer_locked(struct svc_i3c_master * master)1085 static void svc_i3c_master_start_xfer_locked(struct svc_i3c_master *master)
1086 {
1087 struct svc_i3c_xfer *xfer = master->xferqueue.cur;
1088 int ret, i;
1089
1090 if (!xfer)
1091 return;
1092
1093 ret = pm_runtime_resume_and_get(master->dev);
1094 if (ret < 0) {
1095 dev_err(master->dev, "<%s> Cannot get runtime PM.\n", __func__);
1096 return;
1097 }
1098
1099 svc_i3c_master_clear_merrwarn(master);
1100 svc_i3c_master_flush_fifo(master);
1101
1102 for (i = 0; i < xfer->ncmds; i++) {
1103 struct svc_i3c_cmd *cmd = &xfer->cmds[i];
1104
1105 ret = svc_i3c_master_xfer(master, cmd->rnw, xfer->type,
1106 cmd->addr, cmd->in, cmd->out,
1107 cmd->len, &cmd->read_len,
1108 cmd->continued);
1109 if (ret)
1110 break;
1111 }
1112
1113 pm_runtime_mark_last_busy(master->dev);
1114 pm_runtime_put_autosuspend(master->dev);
1115
1116 xfer->ret = ret;
1117 complete(&xfer->comp);
1118
1119 if (ret < 0)
1120 svc_i3c_master_dequeue_xfer_locked(master, xfer);
1121
1122 xfer = list_first_entry_or_null(&master->xferqueue.list,
1123 struct svc_i3c_xfer,
1124 node);
1125 if (xfer)
1126 list_del_init(&xfer->node);
1127
1128 master->xferqueue.cur = xfer;
1129 svc_i3c_master_start_xfer_locked(master);
1130 }
1131
svc_i3c_master_enqueue_xfer(struct svc_i3c_master * master,struct svc_i3c_xfer * xfer)1132 static void svc_i3c_master_enqueue_xfer(struct svc_i3c_master *master,
1133 struct svc_i3c_xfer *xfer)
1134 {
1135 unsigned long flags;
1136
1137 init_completion(&xfer->comp);
1138 spin_lock_irqsave(&master->xferqueue.lock, flags);
1139 if (master->xferqueue.cur) {
1140 list_add_tail(&xfer->node, &master->xferqueue.list);
1141 } else {
1142 master->xferqueue.cur = xfer;
1143 svc_i3c_master_start_xfer_locked(master);
1144 }
1145 spin_unlock_irqrestore(&master->xferqueue.lock, flags);
1146 }
1147
1148 static bool
svc_i3c_master_supports_ccc_cmd(struct i3c_master_controller * master,const struct i3c_ccc_cmd * cmd)1149 svc_i3c_master_supports_ccc_cmd(struct i3c_master_controller *master,
1150 const struct i3c_ccc_cmd *cmd)
1151 {
1152 /* No software support for CCC commands targeting more than one slave */
1153 return (cmd->ndests == 1);
1154 }
1155
svc_i3c_master_send_bdcast_ccc_cmd(struct svc_i3c_master * master,struct i3c_ccc_cmd * ccc)1156 static int svc_i3c_master_send_bdcast_ccc_cmd(struct svc_i3c_master *master,
1157 struct i3c_ccc_cmd *ccc)
1158 {
1159 unsigned int xfer_len = ccc->dests[0].payload.len + 1;
1160 struct svc_i3c_xfer *xfer;
1161 struct svc_i3c_cmd *cmd;
1162 u8 *buf;
1163 int ret;
1164
1165 xfer = svc_i3c_master_alloc_xfer(master, 1);
1166 if (!xfer)
1167 return -ENOMEM;
1168
1169 buf = kmalloc(xfer_len, GFP_KERNEL);
1170 if (!buf) {
1171 svc_i3c_master_free_xfer(xfer);
1172 return -ENOMEM;
1173 }
1174
1175 buf[0] = ccc->id;
1176 memcpy(&buf[1], ccc->dests[0].payload.data, ccc->dests[0].payload.len);
1177
1178 xfer->type = SVC_I3C_MCTRL_TYPE_I3C;
1179
1180 cmd = &xfer->cmds[0];
1181 cmd->addr = ccc->dests[0].addr;
1182 cmd->rnw = ccc->rnw;
1183 cmd->in = NULL;
1184 cmd->out = buf;
1185 cmd->len = xfer_len;
1186 cmd->read_len = 0;
1187 cmd->continued = false;
1188
1189 svc_i3c_master_enqueue_xfer(master, xfer);
1190 if (!wait_for_completion_timeout(&xfer->comp, msecs_to_jiffies(1000)))
1191 svc_i3c_master_dequeue_xfer(master, xfer);
1192
1193 ret = xfer->ret;
1194 kfree(buf);
1195 svc_i3c_master_free_xfer(xfer);
1196
1197 return ret;
1198 }
1199
svc_i3c_master_send_direct_ccc_cmd(struct svc_i3c_master * master,struct i3c_ccc_cmd * ccc)1200 static int svc_i3c_master_send_direct_ccc_cmd(struct svc_i3c_master *master,
1201 struct i3c_ccc_cmd *ccc)
1202 {
1203 unsigned int xfer_len = ccc->dests[0].payload.len;
1204 unsigned int read_len = ccc->rnw ? xfer_len : 0;
1205 struct svc_i3c_xfer *xfer;
1206 struct svc_i3c_cmd *cmd;
1207 int ret;
1208
1209 xfer = svc_i3c_master_alloc_xfer(master, 2);
1210 if (!xfer)
1211 return -ENOMEM;
1212
1213 xfer->type = SVC_I3C_MCTRL_TYPE_I3C;
1214
1215 /* Broadcasted message */
1216 cmd = &xfer->cmds[0];
1217 cmd->addr = I3C_BROADCAST_ADDR;
1218 cmd->rnw = 0;
1219 cmd->in = NULL;
1220 cmd->out = &ccc->id;
1221 cmd->len = 1;
1222 cmd->read_len = 0;
1223 cmd->continued = true;
1224
1225 /* Directed message */
1226 cmd = &xfer->cmds[1];
1227 cmd->addr = ccc->dests[0].addr;
1228 cmd->rnw = ccc->rnw;
1229 cmd->in = ccc->rnw ? ccc->dests[0].payload.data : NULL;
1230 cmd->out = ccc->rnw ? NULL : ccc->dests[0].payload.data,
1231 cmd->len = xfer_len;
1232 cmd->read_len = read_len;
1233 cmd->continued = false;
1234
1235 svc_i3c_master_enqueue_xfer(master, xfer);
1236 if (!wait_for_completion_timeout(&xfer->comp, msecs_to_jiffies(1000)))
1237 svc_i3c_master_dequeue_xfer(master, xfer);
1238
1239 if (cmd->read_len != xfer_len)
1240 ccc->dests[0].payload.len = cmd->read_len;
1241
1242 ret = xfer->ret;
1243 svc_i3c_master_free_xfer(xfer);
1244
1245 return ret;
1246 }
1247
svc_i3c_master_send_ccc_cmd(struct i3c_master_controller * m,struct i3c_ccc_cmd * cmd)1248 static int svc_i3c_master_send_ccc_cmd(struct i3c_master_controller *m,
1249 struct i3c_ccc_cmd *cmd)
1250 {
1251 struct svc_i3c_master *master = to_svc_i3c_master(m);
1252 bool broadcast = cmd->id < 0x80;
1253
1254 if (broadcast)
1255 return svc_i3c_master_send_bdcast_ccc_cmd(master, cmd);
1256 else
1257 return svc_i3c_master_send_direct_ccc_cmd(master, cmd);
1258 }
1259
svc_i3c_master_priv_xfers(struct i3c_dev_desc * dev,struct i3c_priv_xfer * xfers,int nxfers)1260 static int svc_i3c_master_priv_xfers(struct i3c_dev_desc *dev,
1261 struct i3c_priv_xfer *xfers,
1262 int nxfers)
1263 {
1264 struct i3c_master_controller *m = i3c_dev_get_master(dev);
1265 struct svc_i3c_master *master = to_svc_i3c_master(m);
1266 struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
1267 struct svc_i3c_xfer *xfer;
1268 int ret, i;
1269
1270 xfer = svc_i3c_master_alloc_xfer(master, nxfers);
1271 if (!xfer)
1272 return -ENOMEM;
1273
1274 xfer->type = SVC_I3C_MCTRL_TYPE_I3C;
1275
1276 for (i = 0; i < nxfers; i++) {
1277 struct svc_i3c_cmd *cmd = &xfer->cmds[i];
1278
1279 cmd->addr = master->addrs[data->index];
1280 cmd->rnw = xfers[i].rnw;
1281 cmd->in = xfers[i].rnw ? xfers[i].data.in : NULL;
1282 cmd->out = xfers[i].rnw ? NULL : xfers[i].data.out;
1283 cmd->len = xfers[i].len;
1284 cmd->read_len = xfers[i].rnw ? xfers[i].len : 0;
1285 cmd->continued = (i + 1) < nxfers;
1286 }
1287
1288 svc_i3c_master_enqueue_xfer(master, xfer);
1289 if (!wait_for_completion_timeout(&xfer->comp, msecs_to_jiffies(1000)))
1290 svc_i3c_master_dequeue_xfer(master, xfer);
1291
1292 ret = xfer->ret;
1293 svc_i3c_master_free_xfer(xfer);
1294
1295 return ret;
1296 }
1297
svc_i3c_master_i2c_xfers(struct i2c_dev_desc * dev,const struct i2c_msg * xfers,int nxfers)1298 static int svc_i3c_master_i2c_xfers(struct i2c_dev_desc *dev,
1299 const struct i2c_msg *xfers,
1300 int nxfers)
1301 {
1302 struct i3c_master_controller *m = i2c_dev_get_master(dev);
1303 struct svc_i3c_master *master = to_svc_i3c_master(m);
1304 struct svc_i3c_i2c_dev_data *data = i2c_dev_get_master_data(dev);
1305 struct svc_i3c_xfer *xfer;
1306 int ret, i;
1307
1308 xfer = svc_i3c_master_alloc_xfer(master, nxfers);
1309 if (!xfer)
1310 return -ENOMEM;
1311
1312 xfer->type = SVC_I3C_MCTRL_TYPE_I2C;
1313
1314 for (i = 0; i < nxfers; i++) {
1315 struct svc_i3c_cmd *cmd = &xfer->cmds[i];
1316
1317 cmd->addr = master->addrs[data->index];
1318 cmd->rnw = xfers[i].flags & I2C_M_RD;
1319 cmd->in = cmd->rnw ? xfers[i].buf : NULL;
1320 cmd->out = cmd->rnw ? NULL : xfers[i].buf;
1321 cmd->len = xfers[i].len;
1322 cmd->read_len = cmd->rnw ? xfers[i].len : 0;
1323 cmd->continued = (i + 1 < nxfers);
1324 }
1325
1326 svc_i3c_master_enqueue_xfer(master, xfer);
1327 if (!wait_for_completion_timeout(&xfer->comp, msecs_to_jiffies(1000)))
1328 svc_i3c_master_dequeue_xfer(master, xfer);
1329
1330 ret = xfer->ret;
1331 svc_i3c_master_free_xfer(xfer);
1332
1333 return ret;
1334 }
1335
svc_i3c_master_request_ibi(struct i3c_dev_desc * dev,const struct i3c_ibi_setup * req)1336 static int svc_i3c_master_request_ibi(struct i3c_dev_desc *dev,
1337 const struct i3c_ibi_setup *req)
1338 {
1339 struct i3c_master_controller *m = i3c_dev_get_master(dev);
1340 struct svc_i3c_master *master = to_svc_i3c_master(m);
1341 struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
1342 unsigned long flags;
1343 unsigned int i;
1344
1345 if (dev->ibi->max_payload_len > SVC_I3C_FIFO_SIZE) {
1346 dev_err(master->dev, "IBI max payload %d should be < %d\n",
1347 dev->ibi->max_payload_len, SVC_I3C_FIFO_SIZE);
1348 return -ERANGE;
1349 }
1350
1351 data->ibi_pool = i3c_generic_ibi_alloc_pool(dev, req);
1352 if (IS_ERR(data->ibi_pool))
1353 return PTR_ERR(data->ibi_pool);
1354
1355 spin_lock_irqsave(&master->ibi.lock, flags);
1356 for (i = 0; i < master->ibi.num_slots; i++) {
1357 if (!master->ibi.slots[i]) {
1358 data->ibi = i;
1359 master->ibi.slots[i] = dev;
1360 break;
1361 }
1362 }
1363 spin_unlock_irqrestore(&master->ibi.lock, flags);
1364
1365 if (i < master->ibi.num_slots)
1366 return 0;
1367
1368 i3c_generic_ibi_free_pool(data->ibi_pool);
1369 data->ibi_pool = NULL;
1370
1371 return -ENOSPC;
1372 }
1373
svc_i3c_master_free_ibi(struct i3c_dev_desc * dev)1374 static void svc_i3c_master_free_ibi(struct i3c_dev_desc *dev)
1375 {
1376 struct i3c_master_controller *m = i3c_dev_get_master(dev);
1377 struct svc_i3c_master *master = to_svc_i3c_master(m);
1378 struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
1379 unsigned long flags;
1380
1381 spin_lock_irqsave(&master->ibi.lock, flags);
1382 master->ibi.slots[data->ibi] = NULL;
1383 data->ibi = -1;
1384 spin_unlock_irqrestore(&master->ibi.lock, flags);
1385
1386 i3c_generic_ibi_free_pool(data->ibi_pool);
1387 }
1388
svc_i3c_master_enable_ibi(struct i3c_dev_desc * dev)1389 static int svc_i3c_master_enable_ibi(struct i3c_dev_desc *dev)
1390 {
1391 struct i3c_master_controller *m = i3c_dev_get_master(dev);
1392 struct svc_i3c_master *master = to_svc_i3c_master(m);
1393 int ret;
1394
1395 ret = pm_runtime_resume_and_get(master->dev);
1396 if (ret < 0) {
1397 dev_err(master->dev, "<%s> Cannot get runtime PM.\n", __func__);
1398 return ret;
1399 }
1400
1401 svc_i3c_master_enable_interrupts(master, SVC_I3C_MINT_SLVSTART);
1402
1403 return i3c_master_enec_locked(m, dev->info.dyn_addr, I3C_CCC_EVENT_SIR);
1404 }
1405
svc_i3c_master_disable_ibi(struct i3c_dev_desc * dev)1406 static int svc_i3c_master_disable_ibi(struct i3c_dev_desc *dev)
1407 {
1408 struct i3c_master_controller *m = i3c_dev_get_master(dev);
1409 struct svc_i3c_master *master = to_svc_i3c_master(m);
1410 int ret;
1411
1412 svc_i3c_master_disable_interrupts(master);
1413
1414 ret = i3c_master_disec_locked(m, dev->info.dyn_addr, I3C_CCC_EVENT_SIR);
1415
1416 pm_runtime_mark_last_busy(master->dev);
1417 pm_runtime_put_autosuspend(master->dev);
1418
1419 return ret;
1420 }
1421
svc_i3c_master_recycle_ibi_slot(struct i3c_dev_desc * dev,struct i3c_ibi_slot * slot)1422 static void svc_i3c_master_recycle_ibi_slot(struct i3c_dev_desc *dev,
1423 struct i3c_ibi_slot *slot)
1424 {
1425 struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
1426
1427 i3c_generic_ibi_recycle_slot(data->ibi_pool, slot);
1428 }
1429
1430 static const struct i3c_master_controller_ops svc_i3c_master_ops = {
1431 .bus_init = svc_i3c_master_bus_init,
1432 .bus_cleanup = svc_i3c_master_bus_cleanup,
1433 .attach_i3c_dev = svc_i3c_master_attach_i3c_dev,
1434 .detach_i3c_dev = svc_i3c_master_detach_i3c_dev,
1435 .reattach_i3c_dev = svc_i3c_master_reattach_i3c_dev,
1436 .attach_i2c_dev = svc_i3c_master_attach_i2c_dev,
1437 .detach_i2c_dev = svc_i3c_master_detach_i2c_dev,
1438 .do_daa = svc_i3c_master_do_daa,
1439 .supports_ccc_cmd = svc_i3c_master_supports_ccc_cmd,
1440 .send_ccc_cmd = svc_i3c_master_send_ccc_cmd,
1441 .priv_xfers = svc_i3c_master_priv_xfers,
1442 .i2c_xfers = svc_i3c_master_i2c_xfers,
1443 .request_ibi = svc_i3c_master_request_ibi,
1444 .free_ibi = svc_i3c_master_free_ibi,
1445 .recycle_ibi_slot = svc_i3c_master_recycle_ibi_slot,
1446 .enable_ibi = svc_i3c_master_enable_ibi,
1447 .disable_ibi = svc_i3c_master_disable_ibi,
1448 };
1449
svc_i3c_master_prepare_clks(struct svc_i3c_master * master)1450 static int svc_i3c_master_prepare_clks(struct svc_i3c_master *master)
1451 {
1452 int ret = 0;
1453
1454 ret = clk_prepare_enable(master->pclk);
1455 if (ret)
1456 return ret;
1457
1458 ret = clk_prepare_enable(master->fclk);
1459 if (ret) {
1460 clk_disable_unprepare(master->pclk);
1461 return ret;
1462 }
1463
1464 ret = clk_prepare_enable(master->sclk);
1465 if (ret) {
1466 clk_disable_unprepare(master->pclk);
1467 clk_disable_unprepare(master->fclk);
1468 return ret;
1469 }
1470
1471 return 0;
1472 }
1473
svc_i3c_master_unprepare_clks(struct svc_i3c_master * master)1474 static void svc_i3c_master_unprepare_clks(struct svc_i3c_master *master)
1475 {
1476 clk_disable_unprepare(master->pclk);
1477 clk_disable_unprepare(master->fclk);
1478 clk_disable_unprepare(master->sclk);
1479 }
1480
svc_i3c_master_probe(struct platform_device * pdev)1481 static int svc_i3c_master_probe(struct platform_device *pdev)
1482 {
1483 struct device *dev = &pdev->dev;
1484 struct svc_i3c_master *master;
1485 int ret;
1486
1487 master = devm_kzalloc(dev, sizeof(*master), GFP_KERNEL);
1488 if (!master)
1489 return -ENOMEM;
1490
1491 master->regs = devm_platform_ioremap_resource(pdev, 0);
1492 if (IS_ERR(master->regs))
1493 return PTR_ERR(master->regs);
1494
1495 master->pclk = devm_clk_get(dev, "pclk");
1496 if (IS_ERR(master->pclk))
1497 return PTR_ERR(master->pclk);
1498
1499 master->fclk = devm_clk_get(dev, "fast_clk");
1500 if (IS_ERR(master->fclk))
1501 return PTR_ERR(master->fclk);
1502
1503 master->sclk = devm_clk_get(dev, "slow_clk");
1504 if (IS_ERR(master->sclk))
1505 return PTR_ERR(master->sclk);
1506
1507 master->irq = platform_get_irq(pdev, 0);
1508 if (master->irq <= 0)
1509 return -ENOENT;
1510
1511 master->dev = dev;
1512
1513 ret = svc_i3c_master_prepare_clks(master);
1514 if (ret)
1515 return ret;
1516
1517 INIT_WORK(&master->hj_work, svc_i3c_master_hj_work);
1518 INIT_WORK(&master->ibi_work, svc_i3c_master_ibi_work);
1519 ret = devm_request_irq(dev, master->irq, svc_i3c_master_irq_handler,
1520 IRQF_NO_SUSPEND, "svc-i3c-irq", master);
1521 if (ret)
1522 goto err_disable_clks;
1523
1524 master->free_slots = GENMASK(SVC_I3C_MAX_DEVS - 1, 0);
1525
1526 spin_lock_init(&master->xferqueue.lock);
1527 INIT_LIST_HEAD(&master->xferqueue.list);
1528
1529 spin_lock_init(&master->ibi.lock);
1530 master->ibi.num_slots = SVC_I3C_MAX_DEVS;
1531 master->ibi.slots = devm_kcalloc(&pdev->dev, master->ibi.num_slots,
1532 sizeof(*master->ibi.slots),
1533 GFP_KERNEL);
1534 if (!master->ibi.slots) {
1535 ret = -ENOMEM;
1536 goto err_disable_clks;
1537 }
1538
1539 platform_set_drvdata(pdev, master);
1540
1541 pm_runtime_set_autosuspend_delay(&pdev->dev, SVC_I3C_PM_TIMEOUT_MS);
1542 pm_runtime_use_autosuspend(&pdev->dev);
1543 pm_runtime_get_noresume(&pdev->dev);
1544 pm_runtime_set_active(&pdev->dev);
1545 pm_runtime_enable(&pdev->dev);
1546
1547 svc_i3c_master_reset(master);
1548
1549 /* Register the master */
1550 ret = i3c_master_register(&master->base, &pdev->dev,
1551 &svc_i3c_master_ops, false);
1552 if (ret)
1553 goto rpm_disable;
1554
1555 pm_runtime_mark_last_busy(&pdev->dev);
1556 pm_runtime_put_autosuspend(&pdev->dev);
1557
1558 return 0;
1559
1560 rpm_disable:
1561 pm_runtime_dont_use_autosuspend(&pdev->dev);
1562 pm_runtime_put_noidle(&pdev->dev);
1563 pm_runtime_set_suspended(&pdev->dev);
1564 pm_runtime_disable(&pdev->dev);
1565
1566 err_disable_clks:
1567 svc_i3c_master_unprepare_clks(master);
1568
1569 return ret;
1570 }
1571
svc_i3c_master_remove(struct platform_device * pdev)1572 static int svc_i3c_master_remove(struct platform_device *pdev)
1573 {
1574 struct svc_i3c_master *master = platform_get_drvdata(pdev);
1575 int ret;
1576
1577 ret = i3c_master_unregister(&master->base);
1578 if (ret)
1579 return ret;
1580
1581 pm_runtime_dont_use_autosuspend(&pdev->dev);
1582 pm_runtime_disable(&pdev->dev);
1583
1584 return 0;
1585 }
1586
svc_i3c_runtime_suspend(struct device * dev)1587 static int __maybe_unused svc_i3c_runtime_suspend(struct device *dev)
1588 {
1589 struct svc_i3c_master *master = dev_get_drvdata(dev);
1590
1591 svc_i3c_master_unprepare_clks(master);
1592 pinctrl_pm_select_sleep_state(dev);
1593
1594 return 0;
1595 }
1596
svc_i3c_runtime_resume(struct device * dev)1597 static int __maybe_unused svc_i3c_runtime_resume(struct device *dev)
1598 {
1599 struct svc_i3c_master *master = dev_get_drvdata(dev);
1600
1601 pinctrl_pm_select_default_state(dev);
1602 svc_i3c_master_prepare_clks(master);
1603
1604 return 0;
1605 }
1606
1607 static const struct dev_pm_ops svc_i3c_pm_ops = {
1608 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
1609 pm_runtime_force_resume)
1610 SET_RUNTIME_PM_OPS(svc_i3c_runtime_suspend,
1611 svc_i3c_runtime_resume, NULL)
1612 };
1613
1614 static const struct of_device_id svc_i3c_master_of_match_tbl[] = {
1615 { .compatible = "silvaco,i3c-master" },
1616 { /* sentinel */ },
1617 };
1618 MODULE_DEVICE_TABLE(of, svc_i3c_master_of_match_tbl);
1619
1620 static struct platform_driver svc_i3c_master = {
1621 .probe = svc_i3c_master_probe,
1622 .remove = svc_i3c_master_remove,
1623 .driver = {
1624 .name = "silvaco-i3c-master",
1625 .of_match_table = svc_i3c_master_of_match_tbl,
1626 .pm = &svc_i3c_pm_ops,
1627 },
1628 };
1629 module_platform_driver(svc_i3c_master);
1630
1631 MODULE_AUTHOR("Conor Culhane <conor.culhane@silvaco.com>");
1632 MODULE_AUTHOR("Miquel Raynal <miquel.raynal@bootlin.com>");
1633 MODULE_DESCRIPTION("Silvaco dual-role I3C master driver");
1634 MODULE_LICENSE("GPL v2");
1635
