1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2012, The Linux Foundation. All rights reserved.
3  *
4  * Description: CoreSight Trace Memory Controller driver
5  */
6 
7 #include <linux/kernel.h>
8 #include <linux/init.h>
9 #include <linux/types.h>
10 #include <linux/device.h>
11 #include <linux/idr.h>
12 #include <linux/io.h>
13 #include <linux/err.h>
14 #include <linux/fs.h>
15 #include <linux/miscdevice.h>
16 #include <linux/mutex.h>
17 #include <linux/property.h>
18 #include <linux/uaccess.h>
19 #include <linux/slab.h>
20 #include <linux/dma-mapping.h>
21 #include <linux/spinlock.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/of.h>
24 #include <linux/coresight.h>
25 #include <linux/amba/bus.h>
26 
27 #include "coresight-priv.h"
28 #include "coresight-tmc.h"
29 
30 DEFINE_CORESIGHT_DEVLIST(etb_devs, "tmc_etb");
31 DEFINE_CORESIGHT_DEVLIST(etf_devs, "tmc_etf");
32 DEFINE_CORESIGHT_DEVLIST(etr_devs, "tmc_etr");
33 
34 void tmc_wait_for_tmcready(struct tmc_drvdata *drvdata)
35 {
36 	/* Ensure formatter, unformatter and hardware fifo are empty */
37 	if (coresight_timeout(drvdata->base,
38 			      TMC_STS, TMC_STS_TMCREADY_BIT, 1)) {
39 		dev_err(&drvdata->csdev->dev,
40 			"timeout while waiting for TMC to be Ready\n");
41 	}
42 }
43 
44 void tmc_flush_and_stop(struct tmc_drvdata *drvdata)
45 {
46 	u32 ffcr;
47 
48 	ffcr = readl_relaxed(drvdata->base + TMC_FFCR);
49 	ffcr |= TMC_FFCR_STOP_ON_FLUSH;
50 	writel_relaxed(ffcr, drvdata->base + TMC_FFCR);
51 	ffcr |= BIT(TMC_FFCR_FLUSHMAN_BIT);
52 	writel_relaxed(ffcr, drvdata->base + TMC_FFCR);
53 	/* Ensure flush completes */
54 	if (coresight_timeout(drvdata->base,
55 			      TMC_FFCR, TMC_FFCR_FLUSHMAN_BIT, 0)) {
56 		dev_err(&drvdata->csdev->dev,
57 		"timeout while waiting for completion of Manual Flush\n");
58 	}
59 
60 	tmc_wait_for_tmcready(drvdata);
61 }
62 
63 void tmc_enable_hw(struct tmc_drvdata *drvdata)
64 {
65 	writel_relaxed(TMC_CTL_CAPT_EN, drvdata->base + TMC_CTL);
66 }
67 
68 void tmc_disable_hw(struct tmc_drvdata *drvdata)
69 {
70 	writel_relaxed(0x0, drvdata->base + TMC_CTL);
71 }
72 
73 u32 tmc_get_memwidth_mask(struct tmc_drvdata *drvdata)
74 {
75 	u32 mask = 0;
76 
77 	/*
78 	 * When moving RRP or an offset address forward, the new values must
79 	 * be byte-address aligned to the width of the trace memory databus
80 	 * _and_ to a frame boundary (16 byte), whichever is the biggest. For
81 	 * example, for 32-bit, 64-bit and 128-bit wide trace memory, the four
82 	 * LSBs must be 0s. For 256-bit wide trace memory, the five LSBs must
83 	 * be 0s.
84 	 */
85 	switch (drvdata->memwidth) {
86 	case TMC_MEM_INTF_WIDTH_32BITS:
87 	case TMC_MEM_INTF_WIDTH_64BITS:
88 	case TMC_MEM_INTF_WIDTH_128BITS:
89 		mask = GENMASK(31, 4);
90 		break;
91 	case TMC_MEM_INTF_WIDTH_256BITS:
92 		mask = GENMASK(31, 5);
93 		break;
94 	}
95 
96 	return mask;
97 }
98 
99 static int tmc_read_prepare(struct tmc_drvdata *drvdata)
100 {
101 	int ret = 0;
102 
103 	switch (drvdata->config_type) {
104 	case TMC_CONFIG_TYPE_ETB:
105 	case TMC_CONFIG_TYPE_ETF:
106 		ret = tmc_read_prepare_etb(drvdata);
107 		break;
108 	case TMC_CONFIG_TYPE_ETR:
109 		ret = tmc_read_prepare_etr(drvdata);
110 		break;
111 	default:
112 		ret = -EINVAL;
113 	}
114 
115 	if (!ret)
116 		dev_dbg(&drvdata->csdev->dev, "TMC read start\n");
117 
118 	return ret;
119 }
120 
121 static int tmc_read_unprepare(struct tmc_drvdata *drvdata)
122 {
123 	int ret = 0;
124 
125 	switch (drvdata->config_type) {
126 	case TMC_CONFIG_TYPE_ETB:
127 	case TMC_CONFIG_TYPE_ETF:
128 		ret = tmc_read_unprepare_etb(drvdata);
129 		break;
130 	case TMC_CONFIG_TYPE_ETR:
131 		ret = tmc_read_unprepare_etr(drvdata);
132 		break;
133 	default:
134 		ret = -EINVAL;
135 	}
136 
137 	if (!ret)
138 		dev_dbg(&drvdata->csdev->dev, "TMC read end\n");
139 
140 	return ret;
141 }
142 
143 static int tmc_open(struct inode *inode, struct file *file)
144 {
145 	int ret;
146 	struct tmc_drvdata *drvdata = container_of(file->private_data,
147 						   struct tmc_drvdata, miscdev);
148 
149 	ret = tmc_read_prepare(drvdata);
150 	if (ret)
151 		return ret;
152 
153 	nonseekable_open(inode, file);
154 
155 	dev_dbg(&drvdata->csdev->dev, "%s: successfully opened\n", __func__);
156 	return 0;
157 }
158 
159 static inline ssize_t tmc_get_sysfs_trace(struct tmc_drvdata *drvdata,
160 					  loff_t pos, size_t len, char **bufpp)
161 {
162 	switch (drvdata->config_type) {
163 	case TMC_CONFIG_TYPE_ETB:
164 	case TMC_CONFIG_TYPE_ETF:
165 		return tmc_etb_get_sysfs_trace(drvdata, pos, len, bufpp);
166 	case TMC_CONFIG_TYPE_ETR:
167 		return tmc_etr_get_sysfs_trace(drvdata, pos, len, bufpp);
168 	}
169 
170 	return -EINVAL;
171 }
172 
173 static ssize_t tmc_read(struct file *file, char __user *data, size_t len,
174 			loff_t *ppos)
175 {
176 	char *bufp;
177 	ssize_t actual;
178 	struct tmc_drvdata *drvdata = container_of(file->private_data,
179 						   struct tmc_drvdata, miscdev);
180 	actual = tmc_get_sysfs_trace(drvdata, *ppos, len, &bufp);
181 	if (actual <= 0)
182 		return 0;
183 
184 	if (copy_to_user(data, bufp, actual)) {
185 		dev_dbg(&drvdata->csdev->dev,
186 			"%s: copy_to_user failed\n", __func__);
187 		return -EFAULT;
188 	}
189 
190 	*ppos += actual;
191 	dev_dbg(&drvdata->csdev->dev, "%zu bytes copied\n", actual);
192 
193 	return actual;
194 }
195 
196 static int tmc_release(struct inode *inode, struct file *file)
197 {
198 	int ret;
199 	struct tmc_drvdata *drvdata = container_of(file->private_data,
200 						   struct tmc_drvdata, miscdev);
201 
202 	ret = tmc_read_unprepare(drvdata);
203 	if (ret)
204 		return ret;
205 
206 	dev_dbg(&drvdata->csdev->dev, "%s: released\n", __func__);
207 	return 0;
208 }
209 
210 static const struct file_operations tmc_fops = {
211 	.owner		= THIS_MODULE,
212 	.open		= tmc_open,
213 	.read		= tmc_read,
214 	.release	= tmc_release,
215 	.llseek		= no_llseek,
216 };
217 
218 static enum tmc_mem_intf_width tmc_get_memwidth(u32 devid)
219 {
220 	enum tmc_mem_intf_width memwidth;
221 
222 	/*
223 	 * Excerpt from the TRM:
224 	 *
225 	 * DEVID::MEMWIDTH[10:8]
226 	 * 0x2 Memory interface databus is 32 bits wide.
227 	 * 0x3 Memory interface databus is 64 bits wide.
228 	 * 0x4 Memory interface databus is 128 bits wide.
229 	 * 0x5 Memory interface databus is 256 bits wide.
230 	 */
231 	switch (BMVAL(devid, 8, 10)) {
232 	case 0x2:
233 		memwidth = TMC_MEM_INTF_WIDTH_32BITS;
234 		break;
235 	case 0x3:
236 		memwidth = TMC_MEM_INTF_WIDTH_64BITS;
237 		break;
238 	case 0x4:
239 		memwidth = TMC_MEM_INTF_WIDTH_128BITS;
240 		break;
241 	case 0x5:
242 		memwidth = TMC_MEM_INTF_WIDTH_256BITS;
243 		break;
244 	default:
245 		memwidth = 0;
246 	}
247 
248 	return memwidth;
249 }
250 
251 #define coresight_tmc_reg(name, offset)			\
252 	coresight_simple_reg32(struct tmc_drvdata, name, offset)
253 #define coresight_tmc_reg64(name, lo_off, hi_off)	\
254 	coresight_simple_reg64(struct tmc_drvdata, name, lo_off, hi_off)
255 
256 coresight_tmc_reg(rsz, TMC_RSZ);
257 coresight_tmc_reg(sts, TMC_STS);
258 coresight_tmc_reg(trg, TMC_TRG);
259 coresight_tmc_reg(ctl, TMC_CTL);
260 coresight_tmc_reg(ffsr, TMC_FFSR);
261 coresight_tmc_reg(ffcr, TMC_FFCR);
262 coresight_tmc_reg(mode, TMC_MODE);
263 coresight_tmc_reg(pscr, TMC_PSCR);
264 coresight_tmc_reg(axictl, TMC_AXICTL);
265 coresight_tmc_reg(authstatus, TMC_AUTHSTATUS);
266 coresight_tmc_reg(devid, CORESIGHT_DEVID);
267 coresight_tmc_reg64(rrp, TMC_RRP, TMC_RRPHI);
268 coresight_tmc_reg64(rwp, TMC_RWP, TMC_RWPHI);
269 coresight_tmc_reg64(dba, TMC_DBALO, TMC_DBAHI);
270 
271 static struct attribute *coresight_tmc_mgmt_attrs[] = {
272 	&dev_attr_rsz.attr,
273 	&dev_attr_sts.attr,
274 	&dev_attr_rrp.attr,
275 	&dev_attr_rwp.attr,
276 	&dev_attr_trg.attr,
277 	&dev_attr_ctl.attr,
278 	&dev_attr_ffsr.attr,
279 	&dev_attr_ffcr.attr,
280 	&dev_attr_mode.attr,
281 	&dev_attr_pscr.attr,
282 	&dev_attr_devid.attr,
283 	&dev_attr_dba.attr,
284 	&dev_attr_axictl.attr,
285 	&dev_attr_authstatus.attr,
286 	NULL,
287 };
288 
289 static ssize_t trigger_cntr_show(struct device *dev,
290 				 struct device_attribute *attr, char *buf)
291 {
292 	struct tmc_drvdata *drvdata = dev_get_drvdata(dev->parent);
293 	unsigned long val = drvdata->trigger_cntr;
294 
295 	return sprintf(buf, "%#lx\n", val);
296 }
297 
298 static ssize_t trigger_cntr_store(struct device *dev,
299 			     struct device_attribute *attr,
300 			     const char *buf, size_t size)
301 {
302 	int ret;
303 	unsigned long val;
304 	struct tmc_drvdata *drvdata = dev_get_drvdata(dev->parent);
305 
306 	ret = kstrtoul(buf, 16, &val);
307 	if (ret)
308 		return ret;
309 
310 	drvdata->trigger_cntr = val;
311 	return size;
312 }
313 static DEVICE_ATTR_RW(trigger_cntr);
314 
315 static ssize_t buffer_size_show(struct device *dev,
316 				struct device_attribute *attr, char *buf)
317 {
318 	struct tmc_drvdata *drvdata = dev_get_drvdata(dev->parent);
319 
320 	return sprintf(buf, "%#x\n", drvdata->size);
321 }
322 
323 static ssize_t buffer_size_store(struct device *dev,
324 				 struct device_attribute *attr,
325 				 const char *buf, size_t size)
326 {
327 	int ret;
328 	unsigned long val;
329 	struct tmc_drvdata *drvdata = dev_get_drvdata(dev->parent);
330 
331 	/* Only permitted for TMC-ETRs */
332 	if (drvdata->config_type != TMC_CONFIG_TYPE_ETR)
333 		return -EPERM;
334 
335 	ret = kstrtoul(buf, 0, &val);
336 	if (ret)
337 		return ret;
338 	/* The buffer size should be page aligned */
339 	if (val & (PAGE_SIZE - 1))
340 		return -EINVAL;
341 	drvdata->size = val;
342 	return size;
343 }
344 
345 static DEVICE_ATTR_RW(buffer_size);
346 
347 static struct attribute *coresight_tmc_attrs[] = {
348 	&dev_attr_trigger_cntr.attr,
349 	&dev_attr_buffer_size.attr,
350 	NULL,
351 };
352 
353 static const struct attribute_group coresight_tmc_group = {
354 	.attrs = coresight_tmc_attrs,
355 };
356 
357 static const struct attribute_group coresight_tmc_mgmt_group = {
358 	.attrs = coresight_tmc_mgmt_attrs,
359 	.name = "mgmt",
360 };
361 
362 static const struct attribute_group *coresight_tmc_groups[] = {
363 	&coresight_tmc_group,
364 	&coresight_tmc_mgmt_group,
365 	NULL,
366 };
367 
368 static inline bool tmc_etr_can_use_sg(struct device *dev)
369 {
370 	return fwnode_property_present(dev->fwnode, "arm,scatter-gather");
371 }
372 
373 static inline bool tmc_etr_has_non_secure_access(struct tmc_drvdata *drvdata)
374 {
375 	u32 auth = readl_relaxed(drvdata->base + TMC_AUTHSTATUS);
376 
377 	return (auth & TMC_AUTH_NSID_MASK) == 0x3;
378 }
379 
380 /* Detect and initialise the capabilities of a TMC ETR */
381 static int tmc_etr_setup_caps(struct device *parent, u32 devid, void *dev_caps)
382 {
383 	int rc;
384 	u32 dma_mask = 0;
385 	struct tmc_drvdata *drvdata = dev_get_drvdata(parent);
386 
387 	if (!tmc_etr_has_non_secure_access(drvdata))
388 		return -EACCES;
389 
390 	/* Set the unadvertised capabilities */
391 	tmc_etr_init_caps(drvdata, (u32)(unsigned long)dev_caps);
392 
393 	if (!(devid & TMC_DEVID_NOSCAT) && tmc_etr_can_use_sg(parent))
394 		tmc_etr_set_cap(drvdata, TMC_ETR_SG);
395 
396 	/* Check if the AXI address width is available */
397 	if (devid & TMC_DEVID_AXIAW_VALID)
398 		dma_mask = ((devid >> TMC_DEVID_AXIAW_SHIFT) &
399 				TMC_DEVID_AXIAW_MASK);
400 
401 	/*
402 	 * Unless specified in the device configuration, ETR uses a 40-bit
403 	 * AXI master in place of the embedded SRAM of ETB/ETF.
404 	 */
405 	switch (dma_mask) {
406 	case 32:
407 	case 40:
408 	case 44:
409 	case 48:
410 	case 52:
411 		dev_info(parent, "Detected dma mask %dbits\n", dma_mask);
412 		break;
413 	default:
414 		dma_mask = 40;
415 	}
416 
417 	rc = dma_set_mask_and_coherent(parent, DMA_BIT_MASK(dma_mask));
418 	if (rc)
419 		dev_err(parent, "Failed to setup DMA mask: %d\n", rc);
420 	return rc;
421 }
422 
423 static u32 tmc_etr_get_default_buffer_size(struct device *dev)
424 {
425 	u32 size;
426 
427 	if (fwnode_property_read_u32(dev->fwnode, "arm,buffer-size", &size))
428 		size = SZ_1M;
429 	return size;
430 }
431 
432 static int tmc_probe(struct amba_device *adev, const struct amba_id *id)
433 {
434 	int ret = 0;
435 	u32 devid;
436 	void __iomem *base;
437 	struct device *dev = &adev->dev;
438 	struct coresight_platform_data *pdata = NULL;
439 	struct tmc_drvdata *drvdata;
440 	struct resource *res = &adev->res;
441 	struct coresight_desc desc = { 0 };
442 	struct coresight_dev_list *dev_list = NULL;
443 
444 	ret = -ENOMEM;
445 	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
446 	if (!drvdata)
447 		goto out;
448 
449 	dev_set_drvdata(dev, drvdata);
450 
451 	/* Validity for the resource is already checked by the AMBA core */
452 	base = devm_ioremap_resource(dev, res);
453 	if (IS_ERR(base)) {
454 		ret = PTR_ERR(base);
455 		goto out;
456 	}
457 
458 	drvdata->base = base;
459 
460 	spin_lock_init(&drvdata->spinlock);
461 
462 	devid = readl_relaxed(drvdata->base + CORESIGHT_DEVID);
463 	drvdata->config_type = BMVAL(devid, 6, 7);
464 	drvdata->memwidth = tmc_get_memwidth(devid);
465 	/* This device is not associated with a session */
466 	drvdata->pid = -1;
467 
468 	if (drvdata->config_type == TMC_CONFIG_TYPE_ETR)
469 		drvdata->size = tmc_etr_get_default_buffer_size(dev);
470 	else
471 		drvdata->size = readl_relaxed(drvdata->base + TMC_RSZ) * 4;
472 
473 	desc.dev = dev;
474 	desc.groups = coresight_tmc_groups;
475 
476 	switch (drvdata->config_type) {
477 	case TMC_CONFIG_TYPE_ETB:
478 		desc.type = CORESIGHT_DEV_TYPE_SINK;
479 		desc.subtype.sink_subtype = CORESIGHT_DEV_SUBTYPE_SINK_BUFFER;
480 		desc.ops = &tmc_etb_cs_ops;
481 		dev_list = &etb_devs;
482 		break;
483 	case TMC_CONFIG_TYPE_ETR:
484 		desc.type = CORESIGHT_DEV_TYPE_SINK;
485 		desc.subtype.sink_subtype = CORESIGHT_DEV_SUBTYPE_SINK_SYSMEM;
486 		desc.ops = &tmc_etr_cs_ops;
487 		ret = tmc_etr_setup_caps(dev, devid,
488 					 coresight_get_uci_data(id));
489 		if (ret)
490 			goto out;
491 		idr_init(&drvdata->idr);
492 		mutex_init(&drvdata->idr_mutex);
493 		dev_list = &etr_devs;
494 		break;
495 	case TMC_CONFIG_TYPE_ETF:
496 		desc.type = CORESIGHT_DEV_TYPE_LINKSINK;
497 		desc.subtype.sink_subtype = CORESIGHT_DEV_SUBTYPE_SINK_BUFFER;
498 		desc.subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_FIFO;
499 		desc.ops = &tmc_etf_cs_ops;
500 		dev_list = &etf_devs;
501 		break;
502 	default:
503 		pr_err("%s: Unsupported TMC config\n", desc.name);
504 		ret = -EINVAL;
505 		goto out;
506 	}
507 
508 	desc.name = coresight_alloc_device_name(dev_list, dev);
509 	if (!desc.name) {
510 		ret = -ENOMEM;
511 		goto out;
512 	}
513 
514 	pdata = coresight_get_platform_data(dev);
515 	if (IS_ERR(pdata)) {
516 		ret = PTR_ERR(pdata);
517 		goto out;
518 	}
519 	adev->dev.platform_data = pdata;
520 	desc.pdata = pdata;
521 
522 	drvdata->csdev = coresight_register(&desc);
523 	if (IS_ERR(drvdata->csdev)) {
524 		ret = PTR_ERR(drvdata->csdev);
525 		goto out;
526 	}
527 
528 	drvdata->miscdev.name = desc.name;
529 	drvdata->miscdev.minor = MISC_DYNAMIC_MINOR;
530 	drvdata->miscdev.fops = &tmc_fops;
531 	ret = misc_register(&drvdata->miscdev);
532 	if (ret)
533 		coresight_unregister(drvdata->csdev);
534 	else
535 		pm_runtime_put(&adev->dev);
536 out:
537 	return ret;
538 }
539 
540 static void tmc_shutdown(struct amba_device *adev)
541 {
542 	unsigned long flags;
543 	struct tmc_drvdata *drvdata = amba_get_drvdata(adev);
544 
545 	spin_lock_irqsave(&drvdata->spinlock, flags);
546 
547 	if (drvdata->mode == CS_MODE_DISABLED)
548 		goto out;
549 
550 	if (drvdata->config_type == TMC_CONFIG_TYPE_ETR)
551 		tmc_etr_disable_hw(drvdata);
552 
553 	/*
554 	 * We do not care about coresight unregister here unlike remove
555 	 * callback which is required for making coresight modular since
556 	 * the system is going down after this.
557 	 */
558 out:
559 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
560 }
561 
562 static int tmc_remove(struct amba_device *adev)
563 {
564 	struct tmc_drvdata *drvdata = dev_get_drvdata(&adev->dev);
565 
566 	/*
567 	 * Since misc_open() holds a refcount on the f_ops, which is
568 	 * etb fops in this case, device is there until last file
569 	 * handler to this device is closed.
570 	 */
571 	misc_deregister(&drvdata->miscdev);
572 	coresight_unregister(drvdata->csdev);
573 
574 	return 0;
575 }
576 
577 static const struct amba_id tmc_ids[] = {
578 	CS_AMBA_ID(0x000bb961),
579 	/* Coresight SoC 600 TMC-ETR/ETS */
580 	CS_AMBA_ID_DATA(0x000bb9e8, (unsigned long)CORESIGHT_SOC_600_ETR_CAPS),
581 	/* Coresight SoC 600 TMC-ETB */
582 	CS_AMBA_ID(0x000bb9e9),
583 	/* Coresight SoC 600 TMC-ETF */
584 	CS_AMBA_ID(0x000bb9ea),
585 	{ 0, 0},
586 };
587 
588 MODULE_DEVICE_TABLE(amba, tmc_ids);
589 
590 static struct amba_driver tmc_driver = {
591 	.drv = {
592 		.name   = "coresight-tmc",
593 		.owner  = THIS_MODULE,
594 		.suppress_bind_attrs = true,
595 	},
596 	.probe		= tmc_probe,
597 	.shutdown	= tmc_shutdown,
598 	.remove		= tmc_remove,
599 	.id_table	= tmc_ids,
600 };
601 
602 module_amba_driver(tmc_driver);
603 
604 MODULE_AUTHOR("Pratik Patel <pratikp@codeaurora.org>");
605 MODULE_DESCRIPTION("Arm CoreSight Trace Memory Controller driver");
606 MODULE_LICENSE("GPL v2");
607