1 // SPDX-License-Identifier: BSD-3-Clause
2 /*
3 * Copyright (c) 2020, MIPI Alliance, Inc.
4 *
5 * Author: Nicolas Pitre <npitre@baylibre.com>
6 *
7 * Core driver code with main interface to the I3C subsystem.
8 */
9
10 #include <linux/bitfield.h>
11 #include <linux/device.h>
12 #include <linux/errno.h>
13 #include <linux/i3c/master.h>
14 #include <linux/interrupt.h>
15 #include <linux/io.h>
16 #include <linux/iopoll.h>
17 #include <linux/module.h>
18 #include <linux/platform_device.h>
19
20 #include "hci.h"
21 #include "ext_caps.h"
22 #include "cmd.h"
23 #include "dat.h"
24
25
26 /*
27 * Host Controller Capabilities and Operation Registers
28 */
29
30 #define reg_read(r) readl(hci->base_regs + (r))
31 #define reg_write(r, v) writel(v, hci->base_regs + (r))
32 #define reg_set(r, v) reg_write(r, reg_read(r) | (v))
33 #define reg_clear(r, v) reg_write(r, reg_read(r) & ~(v))
34
35 #define HCI_VERSION 0x00 /* HCI Version (in BCD) */
36
37 #define HC_CONTROL 0x04
38 #define HC_CONTROL_BUS_ENABLE BIT(31)
39 #define HC_CONTROL_RESUME BIT(30)
40 #define HC_CONTROL_ABORT BIT(29)
41 #define HC_CONTROL_HALT_ON_CMD_TIMEOUT BIT(12)
42 #define HC_CONTROL_HOT_JOIN_CTRL BIT(8) /* Hot-Join ACK/NACK Control */
43 #define HC_CONTROL_I2C_TARGET_PRESENT BIT(7)
44 #define HC_CONTROL_PIO_MODE BIT(6) /* DMA/PIO Mode Selector */
45 #define HC_CONTROL_DATA_BIG_ENDIAN BIT(4)
46 #define HC_CONTROL_IBA_INCLUDE BIT(0) /* Include I3C Broadcast Address */
47
48 #define MASTER_DEVICE_ADDR 0x08 /* Master Device Address */
49 #define MASTER_DYNAMIC_ADDR_VALID BIT(31) /* Dynamic Address is Valid */
50 #define MASTER_DYNAMIC_ADDR(v) FIELD_PREP(GENMASK(22, 16), v)
51
52 #define HC_CAPABILITIES 0x0c
53 #define HC_CAP_SG_DC_EN BIT(30)
54 #define HC_CAP_SG_IBI_EN BIT(29)
55 #define HC_CAP_SG_CR_EN BIT(28)
56 #define HC_CAP_MAX_DATA_LENGTH GENMASK(24, 22)
57 #define HC_CAP_CMD_SIZE GENMASK(21, 20)
58 #define HC_CAP_DIRECT_COMMANDS_EN BIT(18)
59 #define HC_CAP_MULTI_LANE_EN BIT(15)
60 #define HC_CAP_CMD_CCC_DEFBYTE BIT(10)
61 #define HC_CAP_HDR_BT_EN BIT(8)
62 #define HC_CAP_HDR_TS_EN BIT(7)
63 #define HC_CAP_HDR_DDR_EN BIT(6)
64 #define HC_CAP_NON_CURRENT_MASTER_CAP BIT(5) /* master handoff capable */
65 #define HC_CAP_DATA_BYTE_CFG_EN BIT(4) /* endian selection possible */
66 #define HC_CAP_AUTO_COMMAND BIT(3)
67 #define HC_CAP_COMBO_COMMAND BIT(2)
68
69 #define RESET_CONTROL 0x10
70 #define BUS_RESET BIT(31)
71 #define BUS_RESET_TYPE GENMASK(30, 29)
72 #define IBI_QUEUE_RST BIT(5)
73 #define RX_FIFO_RST BIT(4)
74 #define TX_FIFO_RST BIT(3)
75 #define RESP_QUEUE_RST BIT(2)
76 #define CMD_QUEUE_RST BIT(1)
77 #define SOFT_RST BIT(0) /* Core Reset */
78
79 #define PRESENT_STATE 0x14
80 #define STATE_CURRENT_MASTER BIT(2)
81
82 #define INTR_STATUS 0x20
83 #define INTR_STATUS_ENABLE 0x24
84 #define INTR_SIGNAL_ENABLE 0x28
85 #define INTR_FORCE 0x2c
86 #define INTR_HC_CMD_SEQ_UFLOW_STAT BIT(12) /* Cmd Sequence Underflow */
87 #define INTR_HC_RESET_CANCEL BIT(11) /* HC Cancelled Reset */
88 #define INTR_HC_INTERNAL_ERR BIT(10) /* HC Internal Error */
89 #define INTR_HC_PIO BIT(8) /* cascaded PIO interrupt */
90 #define INTR_HC_RINGS GENMASK(7, 0)
91
92 #define DAT_SECTION 0x30 /* Device Address Table */
93 #define DAT_ENTRY_SIZE GENMASK(31, 28)
94 #define DAT_TABLE_SIZE GENMASK(18, 12)
95 #define DAT_TABLE_OFFSET GENMASK(11, 0)
96
97 #define DCT_SECTION 0x34 /* Device Characteristics Table */
98 #define DCT_ENTRY_SIZE GENMASK(31, 28)
99 #define DCT_TABLE_INDEX GENMASK(23, 19)
100 #define DCT_TABLE_SIZE GENMASK(18, 12)
101 #define DCT_TABLE_OFFSET GENMASK(11, 0)
102
103 #define RING_HEADERS_SECTION 0x38
104 #define RING_HEADERS_OFFSET GENMASK(15, 0)
105
106 #define PIO_SECTION 0x3c
107 #define PIO_REGS_OFFSET GENMASK(15, 0) /* PIO Offset */
108
109 #define EXT_CAPS_SECTION 0x40
110 #define EXT_CAPS_OFFSET GENMASK(15, 0)
111
112 #define IBI_NOTIFY_CTRL 0x58 /* IBI Notify Control */
113 #define IBI_NOTIFY_SIR_REJECTED BIT(3) /* Rejected Target Interrupt Request */
114 #define IBI_NOTIFY_MR_REJECTED BIT(1) /* Rejected Master Request Control */
115 #define IBI_NOTIFY_HJ_REJECTED BIT(0) /* Rejected Hot-Join Control */
116
117 #define DEV_CTX_BASE_LO 0x60
118 #define DEV_CTX_BASE_HI 0x64
119
120
to_i3c_hci(struct i3c_master_controller * m)121 static inline struct i3c_hci *to_i3c_hci(struct i3c_master_controller *m)
122 {
123 return container_of(m, struct i3c_hci, master);
124 }
125
i3c_hci_bus_init(struct i3c_master_controller * m)126 static int i3c_hci_bus_init(struct i3c_master_controller *m)
127 {
128 struct i3c_hci *hci = to_i3c_hci(m);
129 struct i3c_device_info info;
130 int ret;
131
132 DBG("");
133
134 if (hci->cmd == &mipi_i3c_hci_cmd_v1) {
135 ret = mipi_i3c_hci_dat_v1.init(hci);
136 if (ret)
137 return ret;
138 }
139
140 ret = i3c_master_get_free_addr(m, 0);
141 if (ret < 0)
142 return ret;
143 reg_write(MASTER_DEVICE_ADDR,
144 MASTER_DYNAMIC_ADDR(ret) | MASTER_DYNAMIC_ADDR_VALID);
145 memset(&info, 0, sizeof(info));
146 info.dyn_addr = ret;
147 ret = i3c_master_set_info(m, &info);
148 if (ret)
149 return ret;
150
151 ret = hci->io->init(hci);
152 if (ret)
153 return ret;
154
155 reg_set(HC_CONTROL, HC_CONTROL_BUS_ENABLE);
156 DBG("HC_CONTROL = %#x", reg_read(HC_CONTROL));
157
158 return 0;
159 }
160
i3c_hci_bus_cleanup(struct i3c_master_controller * m)161 static void i3c_hci_bus_cleanup(struct i3c_master_controller *m)
162 {
163 struct i3c_hci *hci = to_i3c_hci(m);
164
165 DBG("");
166
167 reg_clear(HC_CONTROL, HC_CONTROL_BUS_ENABLE);
168 hci->io->cleanup(hci);
169 if (hci->cmd == &mipi_i3c_hci_cmd_v1)
170 mipi_i3c_hci_dat_v1.cleanup(hci);
171 }
172
mipi_i3c_hci_resume(struct i3c_hci * hci)173 void mipi_i3c_hci_resume(struct i3c_hci *hci)
174 {
175 /* the HC_CONTROL_RESUME bit is R/W1C so just read and write back */
176 reg_write(HC_CONTROL, reg_read(HC_CONTROL));
177 }
178
179 /* located here rather than pio.c because needed bits are in core reg space */
mipi_i3c_hci_pio_reset(struct i3c_hci * hci)180 void mipi_i3c_hci_pio_reset(struct i3c_hci *hci)
181 {
182 reg_write(RESET_CONTROL, RX_FIFO_RST | TX_FIFO_RST | RESP_QUEUE_RST);
183 }
184
185 /* located here rather than dct.c because needed bits are in core reg space */
mipi_i3c_hci_dct_index_reset(struct i3c_hci * hci)186 void mipi_i3c_hci_dct_index_reset(struct i3c_hci *hci)
187 {
188 reg_write(DCT_SECTION, FIELD_PREP(DCT_TABLE_INDEX, 0));
189 }
190
i3c_hci_send_ccc_cmd(struct i3c_master_controller * m,struct i3c_ccc_cmd * ccc)191 static int i3c_hci_send_ccc_cmd(struct i3c_master_controller *m,
192 struct i3c_ccc_cmd *ccc)
193 {
194 struct i3c_hci *hci = to_i3c_hci(m);
195 struct hci_xfer *xfer;
196 bool raw = !!(hci->quirks & HCI_QUIRK_RAW_CCC);
197 bool prefixed = raw && !!(ccc->id & I3C_CCC_DIRECT);
198 unsigned int nxfers = ccc->ndests + prefixed;
199 DECLARE_COMPLETION_ONSTACK(done);
200 int i, last, ret = 0;
201
202 DBG("cmd=%#x rnw=%d ndests=%d data[0].len=%d",
203 ccc->id, ccc->rnw, ccc->ndests, ccc->dests[0].payload.len);
204
205 xfer = hci_alloc_xfer(nxfers);
206 if (!xfer)
207 return -ENOMEM;
208
209 if (prefixed) {
210 xfer->data = NULL;
211 xfer->data_len = 0;
212 xfer->rnw = false;
213 hci->cmd->prep_ccc(hci, xfer, I3C_BROADCAST_ADDR,
214 ccc->id, true);
215 xfer++;
216 }
217
218 for (i = 0; i < nxfers - prefixed; i++) {
219 xfer[i].data = ccc->dests[i].payload.data;
220 xfer[i].data_len = ccc->dests[i].payload.len;
221 xfer[i].rnw = ccc->rnw;
222 ret = hci->cmd->prep_ccc(hci, &xfer[i], ccc->dests[i].addr,
223 ccc->id, raw);
224 if (ret)
225 goto out;
226 xfer[i].cmd_desc[0] |= CMD_0_ROC;
227 }
228 last = i - 1;
229 xfer[last].cmd_desc[0] |= CMD_0_TOC;
230 xfer[last].completion = &done;
231
232 if (prefixed)
233 xfer--;
234
235 ret = hci->io->queue_xfer(hci, xfer, nxfers);
236 if (ret)
237 goto out;
238 if (!wait_for_completion_timeout(&done, HZ) &&
239 hci->io->dequeue_xfer(hci, xfer, nxfers)) {
240 ret = -ETIME;
241 goto out;
242 }
243 for (i = prefixed; i < nxfers; i++) {
244 if (ccc->rnw)
245 ccc->dests[i - prefixed].payload.len =
246 RESP_DATA_LENGTH(xfer[i].response);
247 if (RESP_STATUS(xfer[i].response) != RESP_SUCCESS) {
248 ret = -EIO;
249 goto out;
250 }
251 }
252
253 if (ccc->rnw)
254 DBG("got: %*ph",
255 ccc->dests[0].payload.len, ccc->dests[0].payload.data);
256
257 out:
258 hci_free_xfer(xfer, nxfers);
259 return ret;
260 }
261
i3c_hci_daa(struct i3c_master_controller * m)262 static int i3c_hci_daa(struct i3c_master_controller *m)
263 {
264 struct i3c_hci *hci = to_i3c_hci(m);
265
266 DBG("");
267
268 return hci->cmd->perform_daa(hci);
269 }
270
i3c_hci_priv_xfers(struct i3c_dev_desc * dev,struct i3c_priv_xfer * i3c_xfers,int nxfers)271 static int i3c_hci_priv_xfers(struct i3c_dev_desc *dev,
272 struct i3c_priv_xfer *i3c_xfers,
273 int nxfers)
274 {
275 struct i3c_master_controller *m = i3c_dev_get_master(dev);
276 struct i3c_hci *hci = to_i3c_hci(m);
277 struct hci_xfer *xfer;
278 DECLARE_COMPLETION_ONSTACK(done);
279 unsigned int size_limit;
280 int i, last, ret = 0;
281
282 DBG("nxfers = %d", nxfers);
283
284 xfer = hci_alloc_xfer(nxfers);
285 if (!xfer)
286 return -ENOMEM;
287
288 size_limit = 1U << (16 + FIELD_GET(HC_CAP_MAX_DATA_LENGTH, hci->caps));
289
290 for (i = 0; i < nxfers; i++) {
291 xfer[i].data_len = i3c_xfers[i].len;
292 ret = -EFBIG;
293 if (xfer[i].data_len >= size_limit)
294 goto out;
295 xfer[i].rnw = i3c_xfers[i].rnw;
296 if (i3c_xfers[i].rnw) {
297 xfer[i].data = i3c_xfers[i].data.in;
298 } else {
299 /* silence the const qualifier warning with a cast */
300 xfer[i].data = (void *) i3c_xfers[i].data.out;
301 }
302 hci->cmd->prep_i3c_xfer(hci, dev, &xfer[i]);
303 xfer[i].cmd_desc[0] |= CMD_0_ROC;
304 }
305 last = i - 1;
306 xfer[last].cmd_desc[0] |= CMD_0_TOC;
307 xfer[last].completion = &done;
308
309 ret = hci->io->queue_xfer(hci, xfer, nxfers);
310 if (ret)
311 goto out;
312 if (!wait_for_completion_timeout(&done, HZ) &&
313 hci->io->dequeue_xfer(hci, xfer, nxfers)) {
314 ret = -ETIME;
315 goto out;
316 }
317 for (i = 0; i < nxfers; i++) {
318 if (i3c_xfers[i].rnw)
319 i3c_xfers[i].len = RESP_DATA_LENGTH(xfer[i].response);
320 if (RESP_STATUS(xfer[i].response) != RESP_SUCCESS) {
321 ret = -EIO;
322 goto out;
323 }
324 }
325
326 out:
327 hci_free_xfer(xfer, nxfers);
328 return ret;
329 }
330
i3c_hci_i2c_xfers(struct i2c_dev_desc * dev,const struct i2c_msg * i2c_xfers,int nxfers)331 static int i3c_hci_i2c_xfers(struct i2c_dev_desc *dev,
332 const struct i2c_msg *i2c_xfers, int nxfers)
333 {
334 struct i3c_master_controller *m = i2c_dev_get_master(dev);
335 struct i3c_hci *hci = to_i3c_hci(m);
336 struct hci_xfer *xfer;
337 DECLARE_COMPLETION_ONSTACK(done);
338 int i, last, ret = 0;
339
340 DBG("nxfers = %d", nxfers);
341
342 xfer = hci_alloc_xfer(nxfers);
343 if (!xfer)
344 return -ENOMEM;
345
346 for (i = 0; i < nxfers; i++) {
347 xfer[i].data = i2c_xfers[i].buf;
348 xfer[i].data_len = i2c_xfers[i].len;
349 xfer[i].rnw = i2c_xfers[i].flags & I2C_M_RD;
350 hci->cmd->prep_i2c_xfer(hci, dev, &xfer[i]);
351 xfer[i].cmd_desc[0] |= CMD_0_ROC;
352 }
353 last = i - 1;
354 xfer[last].cmd_desc[0] |= CMD_0_TOC;
355 xfer[last].completion = &done;
356
357 ret = hci->io->queue_xfer(hci, xfer, nxfers);
358 if (ret)
359 goto out;
360 if (!wait_for_completion_timeout(&done, HZ) &&
361 hci->io->dequeue_xfer(hci, xfer, nxfers)) {
362 ret = -ETIME;
363 goto out;
364 }
365 for (i = 0; i < nxfers; i++) {
366 if (RESP_STATUS(xfer[i].response) != RESP_SUCCESS) {
367 ret = -EIO;
368 goto out;
369 }
370 }
371
372 out:
373 hci_free_xfer(xfer, nxfers);
374 return ret;
375 }
376
i3c_hci_attach_i3c_dev(struct i3c_dev_desc * dev)377 static int i3c_hci_attach_i3c_dev(struct i3c_dev_desc *dev)
378 {
379 struct i3c_master_controller *m = i3c_dev_get_master(dev);
380 struct i3c_hci *hci = to_i3c_hci(m);
381 struct i3c_hci_dev_data *dev_data;
382 int ret;
383
384 DBG("");
385
386 dev_data = kzalloc(sizeof(*dev_data), GFP_KERNEL);
387 if (!dev_data)
388 return -ENOMEM;
389 if (hci->cmd == &mipi_i3c_hci_cmd_v1) {
390 ret = mipi_i3c_hci_dat_v1.alloc_entry(hci);
391 if (ret < 0) {
392 kfree(dev_data);
393 return ret;
394 }
395 mipi_i3c_hci_dat_v1.set_dynamic_addr(hci, ret, dev->info.dyn_addr);
396 dev_data->dat_idx = ret;
397 }
398 i3c_dev_set_master_data(dev, dev_data);
399 return 0;
400 }
401
i3c_hci_reattach_i3c_dev(struct i3c_dev_desc * dev,u8 old_dyn_addr)402 static int i3c_hci_reattach_i3c_dev(struct i3c_dev_desc *dev, u8 old_dyn_addr)
403 {
404 struct i3c_master_controller *m = i3c_dev_get_master(dev);
405 struct i3c_hci *hci = to_i3c_hci(m);
406 struct i3c_hci_dev_data *dev_data = i3c_dev_get_master_data(dev);
407
408 DBG("");
409
410 if (hci->cmd == &mipi_i3c_hci_cmd_v1)
411 mipi_i3c_hci_dat_v1.set_dynamic_addr(hci, dev_data->dat_idx,
412 dev->info.dyn_addr);
413 return 0;
414 }
415
i3c_hci_detach_i3c_dev(struct i3c_dev_desc * dev)416 static void i3c_hci_detach_i3c_dev(struct i3c_dev_desc *dev)
417 {
418 struct i3c_master_controller *m = i3c_dev_get_master(dev);
419 struct i3c_hci *hci = to_i3c_hci(m);
420 struct i3c_hci_dev_data *dev_data = i3c_dev_get_master_data(dev);
421
422 DBG("");
423
424 i3c_dev_set_master_data(dev, NULL);
425 if (hci->cmd == &mipi_i3c_hci_cmd_v1)
426 mipi_i3c_hci_dat_v1.free_entry(hci, dev_data->dat_idx);
427 kfree(dev_data);
428 }
429
i3c_hci_attach_i2c_dev(struct i2c_dev_desc * dev)430 static int i3c_hci_attach_i2c_dev(struct i2c_dev_desc *dev)
431 {
432 struct i3c_master_controller *m = i2c_dev_get_master(dev);
433 struct i3c_hci *hci = to_i3c_hci(m);
434 struct i3c_hci_dev_data *dev_data;
435 int ret;
436
437 DBG("");
438
439 if (hci->cmd != &mipi_i3c_hci_cmd_v1)
440 return 0;
441 dev_data = kzalloc(sizeof(*dev_data), GFP_KERNEL);
442 if (!dev_data)
443 return -ENOMEM;
444 ret = mipi_i3c_hci_dat_v1.alloc_entry(hci);
445 if (ret < 0) {
446 kfree(dev_data);
447 return ret;
448 }
449 mipi_i3c_hci_dat_v1.set_static_addr(hci, ret, dev->addr);
450 mipi_i3c_hci_dat_v1.set_flags(hci, ret, DAT_0_I2C_DEVICE, 0);
451 dev_data->dat_idx = ret;
452 i2c_dev_set_master_data(dev, dev_data);
453 return 0;
454 }
455
i3c_hci_detach_i2c_dev(struct i2c_dev_desc * dev)456 static void i3c_hci_detach_i2c_dev(struct i2c_dev_desc *dev)
457 {
458 struct i3c_master_controller *m = i2c_dev_get_master(dev);
459 struct i3c_hci *hci = to_i3c_hci(m);
460 struct i3c_hci_dev_data *dev_data = i2c_dev_get_master_data(dev);
461
462 DBG("");
463
464 if (dev_data) {
465 i2c_dev_set_master_data(dev, NULL);
466 if (hci->cmd == &mipi_i3c_hci_cmd_v1)
467 mipi_i3c_hci_dat_v1.free_entry(hci, dev_data->dat_idx);
468 kfree(dev_data);
469 }
470 }
471
i3c_hci_request_ibi(struct i3c_dev_desc * dev,const struct i3c_ibi_setup * req)472 static int i3c_hci_request_ibi(struct i3c_dev_desc *dev,
473 const struct i3c_ibi_setup *req)
474 {
475 struct i3c_master_controller *m = i3c_dev_get_master(dev);
476 struct i3c_hci *hci = to_i3c_hci(m);
477 struct i3c_hci_dev_data *dev_data = i3c_dev_get_master_data(dev);
478 unsigned int dat_idx = dev_data->dat_idx;
479
480 if (req->max_payload_len != 0)
481 mipi_i3c_hci_dat_v1.set_flags(hci, dat_idx, DAT_0_IBI_PAYLOAD, 0);
482 else
483 mipi_i3c_hci_dat_v1.clear_flags(hci, dat_idx, DAT_0_IBI_PAYLOAD, 0);
484 return hci->io->request_ibi(hci, dev, req);
485 }
486
i3c_hci_free_ibi(struct i3c_dev_desc * dev)487 static void i3c_hci_free_ibi(struct i3c_dev_desc *dev)
488 {
489 struct i3c_master_controller *m = i3c_dev_get_master(dev);
490 struct i3c_hci *hci = to_i3c_hci(m);
491
492 hci->io->free_ibi(hci, dev);
493 }
494
i3c_hci_enable_ibi(struct i3c_dev_desc * dev)495 static int i3c_hci_enable_ibi(struct i3c_dev_desc *dev)
496 {
497 struct i3c_master_controller *m = i3c_dev_get_master(dev);
498 struct i3c_hci *hci = to_i3c_hci(m);
499 struct i3c_hci_dev_data *dev_data = i3c_dev_get_master_data(dev);
500
501 mipi_i3c_hci_dat_v1.clear_flags(hci, dev_data->dat_idx, DAT_0_SIR_REJECT, 0);
502 return i3c_master_enec_locked(m, dev->info.dyn_addr, I3C_CCC_EVENT_SIR);
503 }
504
i3c_hci_disable_ibi(struct i3c_dev_desc * dev)505 static int i3c_hci_disable_ibi(struct i3c_dev_desc *dev)
506 {
507 struct i3c_master_controller *m = i3c_dev_get_master(dev);
508 struct i3c_hci *hci = to_i3c_hci(m);
509 struct i3c_hci_dev_data *dev_data = i3c_dev_get_master_data(dev);
510
511 mipi_i3c_hci_dat_v1.set_flags(hci, dev_data->dat_idx, DAT_0_SIR_REJECT, 0);
512 return i3c_master_disec_locked(m, dev->info.dyn_addr, I3C_CCC_EVENT_SIR);
513 }
514
i3c_hci_recycle_ibi_slot(struct i3c_dev_desc * dev,struct i3c_ibi_slot * slot)515 static void i3c_hci_recycle_ibi_slot(struct i3c_dev_desc *dev,
516 struct i3c_ibi_slot *slot)
517 {
518 struct i3c_master_controller *m = i3c_dev_get_master(dev);
519 struct i3c_hci *hci = to_i3c_hci(m);
520
521 hci->io->recycle_ibi_slot(hci, dev, slot);
522 }
523
524 static const struct i3c_master_controller_ops i3c_hci_ops = {
525 .bus_init = i3c_hci_bus_init,
526 .bus_cleanup = i3c_hci_bus_cleanup,
527 .do_daa = i3c_hci_daa,
528 .send_ccc_cmd = i3c_hci_send_ccc_cmd,
529 .priv_xfers = i3c_hci_priv_xfers,
530 .i2c_xfers = i3c_hci_i2c_xfers,
531 .attach_i3c_dev = i3c_hci_attach_i3c_dev,
532 .reattach_i3c_dev = i3c_hci_reattach_i3c_dev,
533 .detach_i3c_dev = i3c_hci_detach_i3c_dev,
534 .attach_i2c_dev = i3c_hci_attach_i2c_dev,
535 .detach_i2c_dev = i3c_hci_detach_i2c_dev,
536 .request_ibi = i3c_hci_request_ibi,
537 .free_ibi = i3c_hci_free_ibi,
538 .enable_ibi = i3c_hci_enable_ibi,
539 .disable_ibi = i3c_hci_disable_ibi,
540 .recycle_ibi_slot = i3c_hci_recycle_ibi_slot,
541 };
542
i3c_hci_irq_handler(int irq,void * dev_id)543 static irqreturn_t i3c_hci_irq_handler(int irq, void *dev_id)
544 {
545 struct i3c_hci *hci = dev_id;
546 irqreturn_t result = IRQ_NONE;
547 u32 val;
548
549 val = reg_read(INTR_STATUS);
550 DBG("INTR_STATUS = %#x", val);
551
552 if (val) {
553 reg_write(INTR_STATUS, val);
554 } else {
555 /* v1.0 does not have PIO cascaded notification bits */
556 val |= INTR_HC_PIO;
557 }
558
559 if (val & INTR_HC_RESET_CANCEL) {
560 DBG("cancelled reset");
561 val &= ~INTR_HC_RESET_CANCEL;
562 }
563 if (val & INTR_HC_INTERNAL_ERR) {
564 dev_err(&hci->master.dev, "Host Controller Internal Error\n");
565 val &= ~INTR_HC_INTERNAL_ERR;
566 }
567 if (val & INTR_HC_PIO) {
568 hci->io->irq_handler(hci, 0);
569 val &= ~INTR_HC_PIO;
570 }
571 if (val & INTR_HC_RINGS) {
572 hci->io->irq_handler(hci, val & INTR_HC_RINGS);
573 val &= ~INTR_HC_RINGS;
574 }
575 if (val)
576 dev_err(&hci->master.dev, "unexpected INTR_STATUS %#x\n", val);
577 else
578 result = IRQ_HANDLED;
579
580 return result;
581 }
582
i3c_hci_init(struct i3c_hci * hci)583 static int i3c_hci_init(struct i3c_hci *hci)
584 {
585 u32 regval, offset;
586 int ret;
587
588 /* Validate HCI hardware version */
589 regval = reg_read(HCI_VERSION);
590 hci->version_major = (regval >> 8) & 0xf;
591 hci->version_minor = (regval >> 4) & 0xf;
592 hci->revision = regval & 0xf;
593 dev_notice(&hci->master.dev, "MIPI I3C HCI v%u.%u r%02u\n",
594 hci->version_major, hci->version_minor, hci->revision);
595 /* known versions */
596 switch (regval & ~0xf) {
597 case 0x100: /* version 1.0 */
598 case 0x110: /* version 1.1 */
599 case 0x200: /* version 2.0 */
600 break;
601 default:
602 dev_err(&hci->master.dev, "unsupported HCI version\n");
603 return -EPROTONOSUPPORT;
604 }
605
606 hci->caps = reg_read(HC_CAPABILITIES);
607 DBG("caps = %#x", hci->caps);
608
609 regval = reg_read(DAT_SECTION);
610 offset = FIELD_GET(DAT_TABLE_OFFSET, regval);
611 hci->DAT_regs = offset ? hci->base_regs + offset : NULL;
612 hci->DAT_entries = FIELD_GET(DAT_TABLE_SIZE, regval);
613 hci->DAT_entry_size = FIELD_GET(DAT_ENTRY_SIZE, regval);
614 dev_info(&hci->master.dev, "DAT: %u %u-bytes entries at offset %#x\n",
615 hci->DAT_entries, hci->DAT_entry_size * 4, offset);
616
617 regval = reg_read(DCT_SECTION);
618 offset = FIELD_GET(DCT_TABLE_OFFSET, regval);
619 hci->DCT_regs = offset ? hci->base_regs + offset : NULL;
620 hci->DCT_entries = FIELD_GET(DCT_TABLE_SIZE, regval);
621 hci->DCT_entry_size = FIELD_GET(DCT_ENTRY_SIZE, regval);
622 dev_info(&hci->master.dev, "DCT: %u %u-bytes entries at offset %#x\n",
623 hci->DCT_entries, hci->DCT_entry_size * 4, offset);
624
625 regval = reg_read(RING_HEADERS_SECTION);
626 offset = FIELD_GET(RING_HEADERS_OFFSET, regval);
627 hci->RHS_regs = offset ? hci->base_regs + offset : NULL;
628 dev_info(&hci->master.dev, "Ring Headers at offset %#x\n", offset);
629
630 regval = reg_read(PIO_SECTION);
631 offset = FIELD_GET(PIO_REGS_OFFSET, regval);
632 hci->PIO_regs = offset ? hci->base_regs + offset : NULL;
633 dev_info(&hci->master.dev, "PIO section at offset %#x\n", offset);
634
635 regval = reg_read(EXT_CAPS_SECTION);
636 offset = FIELD_GET(EXT_CAPS_OFFSET, regval);
637 hci->EXTCAPS_regs = offset ? hci->base_regs + offset : NULL;
638 dev_info(&hci->master.dev, "Extended Caps at offset %#x\n", offset);
639
640 ret = i3c_hci_parse_ext_caps(hci);
641 if (ret)
642 return ret;
643
644 /*
645 * Now let's reset the hardware.
646 * SOFT_RST must be clear before we write to it.
647 * Then we must wait until it clears again.
648 */
649 ret = readx_poll_timeout(reg_read, RESET_CONTROL, regval,
650 !(regval & SOFT_RST), 1, 10000);
651 if (ret)
652 return -ENXIO;
653 reg_write(RESET_CONTROL, SOFT_RST);
654 ret = readx_poll_timeout(reg_read, RESET_CONTROL, regval,
655 !(regval & SOFT_RST), 1, 10000);
656 if (ret)
657 return -ENXIO;
658
659 /* Disable all interrupts and allow all signal updates */
660 reg_write(INTR_SIGNAL_ENABLE, 0x0);
661 reg_write(INTR_STATUS_ENABLE, 0xffffffff);
662
663 /* Make sure our data ordering fits the host's */
664 regval = reg_read(HC_CONTROL);
665 if (IS_ENABLED(CONFIG_BIG_ENDIAN)) {
666 if (!(regval & HC_CONTROL_DATA_BIG_ENDIAN)) {
667 regval |= HC_CONTROL_DATA_BIG_ENDIAN;
668 reg_write(HC_CONTROL, regval);
669 regval = reg_read(HC_CONTROL);
670 if (!(regval & HC_CONTROL_DATA_BIG_ENDIAN)) {
671 dev_err(&hci->master.dev, "cannot set BE mode\n");
672 return -EOPNOTSUPP;
673 }
674 }
675 } else {
676 if (regval & HC_CONTROL_DATA_BIG_ENDIAN) {
677 regval &= ~HC_CONTROL_DATA_BIG_ENDIAN;
678 reg_write(HC_CONTROL, regval);
679 regval = reg_read(HC_CONTROL);
680 if (regval & HC_CONTROL_DATA_BIG_ENDIAN) {
681 dev_err(&hci->master.dev, "cannot clear BE mode\n");
682 return -EOPNOTSUPP;
683 }
684 }
685 }
686
687 /* Select our command descriptor model */
688 switch (FIELD_GET(HC_CAP_CMD_SIZE, hci->caps)) {
689 case 0:
690 hci->cmd = &mipi_i3c_hci_cmd_v1;
691 break;
692 case 1:
693 hci->cmd = &mipi_i3c_hci_cmd_v2;
694 break;
695 default:
696 dev_err(&hci->master.dev, "wrong CMD_SIZE capability value\n");
697 return -EINVAL;
698 }
699
700 /* Try activating DMA operations first */
701 if (hci->RHS_regs) {
702 reg_clear(HC_CONTROL, HC_CONTROL_PIO_MODE);
703 if (reg_read(HC_CONTROL) & HC_CONTROL_PIO_MODE) {
704 dev_err(&hci->master.dev, "PIO mode is stuck\n");
705 ret = -EIO;
706 } else {
707 hci->io = &mipi_i3c_hci_dma;
708 dev_info(&hci->master.dev, "Using DMA\n");
709 }
710 }
711
712 /* If no DMA, try PIO */
713 if (!hci->io && hci->PIO_regs) {
714 reg_set(HC_CONTROL, HC_CONTROL_PIO_MODE);
715 if (!(reg_read(HC_CONTROL) & HC_CONTROL_PIO_MODE)) {
716 dev_err(&hci->master.dev, "DMA mode is stuck\n");
717 ret = -EIO;
718 } else {
719 hci->io = &mipi_i3c_hci_pio;
720 dev_info(&hci->master.dev, "Using PIO\n");
721 }
722 }
723
724 if (!hci->io) {
725 dev_err(&hci->master.dev, "neither DMA nor PIO can be used\n");
726 if (!ret)
727 ret = -EINVAL;
728 return ret;
729 }
730
731 return 0;
732 }
733
i3c_hci_probe(struct platform_device * pdev)734 static int i3c_hci_probe(struct platform_device *pdev)
735 {
736 struct i3c_hci *hci;
737 int irq, ret;
738
739 hci = devm_kzalloc(&pdev->dev, sizeof(*hci), GFP_KERNEL);
740 if (!hci)
741 return -ENOMEM;
742 hci->base_regs = devm_platform_ioremap_resource(pdev, 0);
743 if (IS_ERR(hci->base_regs))
744 return PTR_ERR(hci->base_regs);
745
746 platform_set_drvdata(pdev, hci);
747 /* temporary for dev_printk's, to be replaced in i3c_master_register */
748 hci->master.dev.init_name = dev_name(&pdev->dev);
749
750 ret = i3c_hci_init(hci);
751 if (ret)
752 return ret;
753
754 irq = platform_get_irq(pdev, 0);
755 ret = devm_request_irq(&pdev->dev, irq, i3c_hci_irq_handler,
756 0, NULL, hci);
757 if (ret)
758 return ret;
759
760 ret = i3c_master_register(&hci->master, &pdev->dev,
761 &i3c_hci_ops, false);
762 if (ret)
763 return ret;
764
765 return 0;
766 }
767
i3c_hci_remove(struct platform_device * pdev)768 static int i3c_hci_remove(struct platform_device *pdev)
769 {
770 struct i3c_hci *hci = platform_get_drvdata(pdev);
771 int ret;
772
773 ret = i3c_master_unregister(&hci->master);
774 if (ret)
775 return ret;
776
777 return 0;
778 }
779
780 static const __maybe_unused struct of_device_id i3c_hci_of_match[] = {
781 { .compatible = "mipi-i3c-hci", },
782 {},
783 };
784 MODULE_DEVICE_TABLE(of, i3c_hci_of_match);
785
786 static struct platform_driver i3c_hci_driver = {
787 .probe = i3c_hci_probe,
788 .remove = i3c_hci_remove,
789 .driver = {
790 .name = "mipi-i3c-hci",
791 .of_match_table = of_match_ptr(i3c_hci_of_match),
792 },
793 };
794 module_platform_driver(i3c_hci_driver);
795
796 MODULE_AUTHOR("Nicolas Pitre <npitre@baylibre.com>");
797 MODULE_DESCRIPTION("MIPI I3C HCI driver");
798 MODULE_LICENSE("Dual BSD/GPL");
799
