1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2019, The Linaro Limited. All rights reserved.
4  */
5 
6 #include <dt-bindings/arm/coresight-cti-dt.h>
7 #include <linux/of.h>
8 
9 #include "coresight-cti.h"
10 
11 /* Number of CTI signals in the v8 architecturally defined connection */
12 #define NR_V8PE_IN_SIGS		2
13 #define NR_V8PE_OUT_SIGS	3
14 #define NR_V8ETM_INOUT_SIGS	4
15 
16 /* CTI device tree trigger connection node keyword */
17 #define CTI_DT_CONNS		"trig-conns"
18 
19 /* CTI device tree connection property keywords */
20 #define CTI_DT_V8ARCH_COMPAT	"arm,coresight-cti-v8-arch"
21 #define CTI_DT_CSDEV_ASSOC	"arm,cs-dev-assoc"
22 #define CTI_DT_TRIGIN_SIGS	"arm,trig-in-sigs"
23 #define CTI_DT_TRIGOUT_SIGS	"arm,trig-out-sigs"
24 #define CTI_DT_TRIGIN_TYPES	"arm,trig-in-types"
25 #define CTI_DT_TRIGOUT_TYPES	"arm,trig-out-types"
26 #define CTI_DT_FILTER_OUT_SIGS	"arm,trig-filters"
27 #define CTI_DT_CONN_NAME	"arm,trig-conn-name"
28 #define CTI_DT_CTM_ID		"arm,cti-ctm-id"
29 
30 #ifdef CONFIG_OF
31 /*
32  * CTI can be bound to a CPU, or a system device.
33  * CPU can be declared at the device top level or in a connections node
34  * so need to check relative to node not device.
35  */
36 static int of_cti_get_cpu_at_node(const struct device_node *node)
37 {
38 	int cpu;
39 	struct device_node *dn;
40 
41 	if (node == NULL)
42 		return -1;
43 
44 	dn = of_parse_phandle(node, "cpu", 0);
45 	/* CTI affinity defaults to no cpu */
46 	if (!dn)
47 		return -1;
48 	cpu = of_cpu_node_to_id(dn);
49 	of_node_put(dn);
50 
51 	/* No Affinity  if no cpu nodes are found */
52 	return (cpu < 0) ? -1 : cpu;
53 }
54 
55 #else
56 static int of_cti_get_cpu_at_node(const struct device_node *node)
57 {
58 	return -1;
59 }
60 
61 #endif
62 
63 /*
64  * CTI can be bound to a CPU, or a system device.
65  * CPU can be declared at the device top level or in a connections node
66  * so need to check relative to node not device.
67  */
68 static int cti_plat_get_cpu_at_node(struct fwnode_handle *fwnode)
69 {
70 	if (is_of_node(fwnode))
71 		return of_cti_get_cpu_at_node(to_of_node(fwnode));
72 	return -1;
73 }
74 
75 const char *cti_plat_get_node_name(struct fwnode_handle *fwnode)
76 {
77 	if (is_of_node(fwnode))
78 		return of_node_full_name(to_of_node(fwnode));
79 	return "unknown";
80 }
81 
82 /*
83  * Extract a name from the fwnode.
84  * If the device associated with the node is a coresight_device, then return
85  * that name and the coresight_device pointer, otherwise return the node name.
86  */
87 static const char *
88 cti_plat_get_csdev_or_node_name(struct fwnode_handle *fwnode,
89 				struct coresight_device **csdev)
90 {
91 	const char *name = NULL;
92 	*csdev = coresight_find_csdev_by_fwnode(fwnode);
93 	if (*csdev)
94 		name = dev_name(&(*csdev)->dev);
95 	else
96 		name = cti_plat_get_node_name(fwnode);
97 	return name;
98 }
99 
100 static bool cti_plat_node_name_eq(struct fwnode_handle *fwnode,
101 				  const char *name)
102 {
103 	if (is_of_node(fwnode))
104 		return of_node_name_eq(to_of_node(fwnode), name);
105 	return false;
106 }
107 
108 static int cti_plat_create_v8_etm_connection(struct device *dev,
109 					     struct cti_drvdata *drvdata)
110 {
111 	int ret = -ENOMEM, i;
112 	struct fwnode_handle *root_fwnode, *cs_fwnode;
113 	const char *assoc_name = NULL;
114 	struct coresight_device *csdev;
115 	struct cti_trig_con *tc = NULL;
116 
117 	root_fwnode = dev_fwnode(dev);
118 	if (IS_ERR_OR_NULL(root_fwnode))
119 		return -EINVAL;
120 
121 	/* Can optionally have an etm node - return if not  */
122 	cs_fwnode = fwnode_find_reference(root_fwnode, CTI_DT_CSDEV_ASSOC, 0);
123 	if (IS_ERR_OR_NULL(cs_fwnode))
124 		return 0;
125 
126 	/* allocate memory */
127 	tc = cti_allocate_trig_con(dev, NR_V8ETM_INOUT_SIGS,
128 				   NR_V8ETM_INOUT_SIGS);
129 	if (!tc)
130 		goto create_v8_etm_out;
131 
132 	/* build connection data */
133 	tc->con_in->used_mask = 0xF0; /* sigs <4,5,6,7> */
134 	tc->con_out->used_mask = 0xF0; /* sigs <4,5,6,7> */
135 
136 	/*
137 	 * The EXTOUT type signals from the ETM are connected to a set of input
138 	 * triggers on the CTI, the EXTIN being connected to output triggers.
139 	 */
140 	for (i = 0; i < NR_V8ETM_INOUT_SIGS; i++) {
141 		tc->con_in->sig_types[i] = ETM_EXTOUT;
142 		tc->con_out->sig_types[i] = ETM_EXTIN;
143 	}
144 
145 	/*
146 	 * We look to see if the ETM coresight device associated with this
147 	 * handle has been registered with the system - i.e. probed before
148 	 * this CTI. If so csdev will be non NULL and we can use the device
149 	 * name and pass the csdev to the connection entry function where
150 	 * the association will be recorded.
151 	 * If not, then simply record the name in the connection data, the
152 	 * probing of the ETM will call into the CTI driver API to update the
153 	 * association then.
154 	 */
155 	assoc_name = cti_plat_get_csdev_or_node_name(cs_fwnode, &csdev);
156 	ret = cti_add_connection_entry(dev, drvdata, tc, csdev, assoc_name);
157 
158 create_v8_etm_out:
159 	fwnode_handle_put(cs_fwnode);
160 	return ret;
161 }
162 
163 /*
164  * Create an architecturally defined v8 connection
165  * must have a cpu, can have an ETM.
166  */
167 static int cti_plat_create_v8_connections(struct device *dev,
168 					  struct cti_drvdata *drvdata)
169 {
170 	struct cti_device *cti_dev = &drvdata->ctidev;
171 	struct cti_trig_con *tc = NULL;
172 	int cpuid = 0;
173 	char cpu_name_str[16];
174 	int ret = -ENOMEM;
175 
176 	/* Must have a cpu node */
177 	cpuid = cti_plat_get_cpu_at_node(dev_fwnode(dev));
178 	if (cpuid < 0) {
179 		dev_warn(dev,
180 			 "ARM v8 architectural CTI connection: missing cpu\n");
181 		return -EINVAL;
182 	}
183 	cti_dev->cpu = cpuid;
184 
185 	/* Allocate the v8 cpu connection memory */
186 	tc = cti_allocate_trig_con(dev, NR_V8PE_IN_SIGS, NR_V8PE_OUT_SIGS);
187 	if (!tc)
188 		goto of_create_v8_out;
189 
190 	/* Set the v8 PE CTI connection data */
191 	tc->con_in->used_mask = 0x3; /* sigs <0 1> */
192 	tc->con_in->sig_types[0] = PE_DBGTRIGGER;
193 	tc->con_in->sig_types[1] = PE_PMUIRQ;
194 	tc->con_out->used_mask = 0x7; /* sigs <0 1 2 > */
195 	tc->con_out->sig_types[0] = PE_EDBGREQ;
196 	tc->con_out->sig_types[1] = PE_DBGRESTART;
197 	tc->con_out->sig_types[2] = PE_CTIIRQ;
198 	scnprintf(cpu_name_str, sizeof(cpu_name_str), "cpu%d", cpuid);
199 
200 	ret = cti_add_connection_entry(dev, drvdata, tc, NULL, cpu_name_str);
201 	if (ret)
202 		goto of_create_v8_out;
203 
204 	/* Create the v8 ETM associated connection */
205 	ret = cti_plat_create_v8_etm_connection(dev, drvdata);
206 	if (ret)
207 		goto of_create_v8_out;
208 
209 	/* filter pe_edbgreq - PE trigout sig <0> */
210 	drvdata->config.trig_out_filter |= 0x1;
211 
212 of_create_v8_out:
213 	return ret;
214 }
215 
216 static int cti_plat_check_v8_arch_compatible(struct device *dev)
217 {
218 	struct fwnode_handle *fwnode = dev_fwnode(dev);
219 
220 	if (is_of_node(fwnode))
221 		return of_device_is_compatible(to_of_node(fwnode),
222 					       CTI_DT_V8ARCH_COMPAT);
223 	return 0;
224 }
225 
226 static int cti_plat_count_sig_elements(const struct fwnode_handle *fwnode,
227 				       const char *name)
228 {
229 	int nr_elem = fwnode_property_count_u32(fwnode, name);
230 
231 	return (nr_elem < 0 ? 0 : nr_elem);
232 }
233 
234 static int cti_plat_read_trig_group(struct cti_trig_grp *tgrp,
235 				    const struct fwnode_handle *fwnode,
236 				    const char *grp_name)
237 {
238 	int idx, err = 0;
239 	u32 *values;
240 
241 	if (!tgrp->nr_sigs)
242 		return 0;
243 
244 	values = kcalloc(tgrp->nr_sigs, sizeof(u32), GFP_KERNEL);
245 	if (!values)
246 		return -ENOMEM;
247 
248 	err = fwnode_property_read_u32_array(fwnode, grp_name,
249 					     values, tgrp->nr_sigs);
250 
251 	if (!err) {
252 		/* set the signal usage mask */
253 		for (idx = 0; idx < tgrp->nr_sigs; idx++)
254 			tgrp->used_mask |= BIT(values[idx]);
255 	}
256 
257 	kfree(values);
258 	return err;
259 }
260 
261 static int cti_plat_read_trig_types(struct cti_trig_grp *tgrp,
262 				    const struct fwnode_handle *fwnode,
263 				    const char *type_name)
264 {
265 	int items, err = 0, nr_sigs;
266 	u32 *values = NULL, i;
267 
268 	/* allocate an array according to number of signals in connection */
269 	nr_sigs = tgrp->nr_sigs;
270 	if (!nr_sigs)
271 		return 0;
272 
273 	/* see if any types have been included in the device description */
274 	items = cti_plat_count_sig_elements(fwnode, type_name);
275 	if (items > nr_sigs)
276 		return -EINVAL;
277 
278 	/* need an array to store the values iff there are any */
279 	if (items) {
280 		values = kcalloc(items, sizeof(u32), GFP_KERNEL);
281 		if (!values)
282 			return -ENOMEM;
283 
284 		err = fwnode_property_read_u32_array(fwnode, type_name,
285 						     values, items);
286 		if (err)
287 			goto read_trig_types_out;
288 	}
289 
290 	/*
291 	 * Match type id to signal index, 1st type to 1st index etc.
292 	 * If fewer types than signals default remainder to GEN_IO.
293 	 */
294 	for (i = 0; i < nr_sigs; i++) {
295 		if (i < items) {
296 			tgrp->sig_types[i] =
297 				values[i] < CTI_TRIG_MAX ? values[i] : GEN_IO;
298 		} else {
299 			tgrp->sig_types[i] = GEN_IO;
300 		}
301 	}
302 
303 read_trig_types_out:
304 	kfree(values);
305 	return err;
306 }
307 
308 static int cti_plat_process_filter_sigs(struct cti_drvdata *drvdata,
309 					const struct fwnode_handle *fwnode)
310 {
311 	struct cti_trig_grp *tg = NULL;
312 	int err = 0, nr_filter_sigs;
313 
314 	nr_filter_sigs = cti_plat_count_sig_elements(fwnode,
315 						     CTI_DT_FILTER_OUT_SIGS);
316 	if (nr_filter_sigs == 0)
317 		return 0;
318 
319 	if (nr_filter_sigs > drvdata->config.nr_trig_max)
320 		return -EINVAL;
321 
322 	tg = kzalloc(sizeof(*tg), GFP_KERNEL);
323 	if (!tg)
324 		return -ENOMEM;
325 
326 	err = cti_plat_read_trig_group(tg, fwnode, CTI_DT_FILTER_OUT_SIGS);
327 	if (!err)
328 		drvdata->config.trig_out_filter |= tg->used_mask;
329 
330 	kfree(tg);
331 	return err;
332 }
333 
334 static int cti_plat_create_connection(struct device *dev,
335 				      struct cti_drvdata *drvdata,
336 				      struct fwnode_handle *fwnode)
337 {
338 	struct cti_trig_con *tc = NULL;
339 	int cpuid = -1, err = 0;
340 	struct fwnode_handle *cs_fwnode = NULL;
341 	struct coresight_device *csdev = NULL;
342 	const char *assoc_name = "unknown";
343 	char cpu_name_str[16];
344 	int nr_sigs_in, nr_sigs_out;
345 
346 	/* look to see how many in and out signals we have */
347 	nr_sigs_in = cti_plat_count_sig_elements(fwnode, CTI_DT_TRIGIN_SIGS);
348 	nr_sigs_out = cti_plat_count_sig_elements(fwnode, CTI_DT_TRIGOUT_SIGS);
349 
350 	if ((nr_sigs_in > drvdata->config.nr_trig_max) ||
351 	    (nr_sigs_out > drvdata->config.nr_trig_max))
352 		return -EINVAL;
353 
354 	tc = cti_allocate_trig_con(dev, nr_sigs_in, nr_sigs_out);
355 	if (!tc)
356 		return -ENOMEM;
357 
358 	/* look for the signals properties. */
359 	err = cti_plat_read_trig_group(tc->con_in, fwnode,
360 				       CTI_DT_TRIGIN_SIGS);
361 	if (err)
362 		goto create_con_err;
363 
364 	err = cti_plat_read_trig_types(tc->con_in, fwnode,
365 				       CTI_DT_TRIGIN_TYPES);
366 	if (err)
367 		goto create_con_err;
368 
369 	err = cti_plat_read_trig_group(tc->con_out, fwnode,
370 				       CTI_DT_TRIGOUT_SIGS);
371 	if (err)
372 		goto create_con_err;
373 
374 	err = cti_plat_read_trig_types(tc->con_out, fwnode,
375 				       CTI_DT_TRIGOUT_TYPES);
376 	if (err)
377 		goto create_con_err;
378 
379 	err = cti_plat_process_filter_sigs(drvdata, fwnode);
380 	if (err)
381 		goto create_con_err;
382 
383 	/* read the connection name if set - may be overridden by later */
384 	fwnode_property_read_string(fwnode, CTI_DT_CONN_NAME, &assoc_name);
385 
386 	/* associated cpu ? */
387 	cpuid = cti_plat_get_cpu_at_node(fwnode);
388 	if (cpuid >= 0) {
389 		drvdata->ctidev.cpu = cpuid;
390 		scnprintf(cpu_name_str, sizeof(cpu_name_str), "cpu%d", cpuid);
391 		assoc_name = cpu_name_str;
392 	} else {
393 		/* associated device ? */
394 		cs_fwnode = fwnode_find_reference(fwnode,
395 						  CTI_DT_CSDEV_ASSOC, 0);
396 		if (!IS_ERR_OR_NULL(cs_fwnode)) {
397 			assoc_name = cti_plat_get_csdev_or_node_name(cs_fwnode,
398 								     &csdev);
399 			fwnode_handle_put(cs_fwnode);
400 		}
401 	}
402 	/* set up a connection */
403 	err = cti_add_connection_entry(dev, drvdata, tc, csdev, assoc_name);
404 
405 create_con_err:
406 	return err;
407 }
408 
409 static int cti_plat_create_impdef_connections(struct device *dev,
410 					      struct cti_drvdata *drvdata)
411 {
412 	int rc = 0;
413 	struct fwnode_handle *fwnode = dev_fwnode(dev);
414 	struct fwnode_handle *child = NULL;
415 
416 	if (IS_ERR_OR_NULL(fwnode))
417 		return -EINVAL;
418 
419 	fwnode_for_each_child_node(fwnode, child) {
420 		if (cti_plat_node_name_eq(child, CTI_DT_CONNS))
421 			rc = cti_plat_create_connection(dev, drvdata,
422 							child);
423 		if (rc != 0)
424 			break;
425 	}
426 	fwnode_handle_put(child);
427 
428 	return rc;
429 }
430 
431 /* get the hardware configuration & connection data. */
432 int cti_plat_get_hw_data(struct device *dev,
433 			 struct cti_drvdata *drvdata)
434 {
435 	int rc = 0;
436 	struct cti_device *cti_dev = &drvdata->ctidev;
437 
438 	/* get any CTM ID - defaults to 0 */
439 	device_property_read_u32(dev, CTI_DT_CTM_ID, &cti_dev->ctm_id);
440 
441 	/* check for a v8 architectural CTI device */
442 	if (cti_plat_check_v8_arch_compatible(dev))
443 		rc = cti_plat_create_v8_connections(dev, drvdata);
444 	else
445 		rc = cti_plat_create_impdef_connections(dev, drvdata);
446 	if (rc)
447 		return rc;
448 
449 	/* if no connections, just add a single default based on max IN-OUT */
450 	if (cti_dev->nr_trig_con == 0)
451 		rc = cti_add_default_connection(dev, drvdata);
452 	return rc;
453 }
454 
455 struct coresight_platform_data *
456 coresight_cti_get_platform_data(struct device *dev)
457 {
458 	int ret = -ENOENT;
459 	struct coresight_platform_data *pdata = NULL;
460 	struct fwnode_handle *fwnode = dev_fwnode(dev);
461 	struct cti_drvdata *drvdata = dev_get_drvdata(dev);
462 
463 	if (IS_ERR_OR_NULL(fwnode))
464 		goto error;
465 
466 	/*
467 	 * Alloc platform data but leave it zero init. CTI does not use the
468 	 * same connection infrastructuree as trace path components but an
469 	 * empty struct enables us to use the standard coresight component
470 	 * registration code.
471 	 */
472 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
473 	if (!pdata) {
474 		ret = -ENOMEM;
475 		goto error;
476 	}
477 
478 	/* get some CTI specifics */
479 	ret = cti_plat_get_hw_data(dev, drvdata);
480 
481 	if (!ret)
482 		return pdata;
483 error:
484 	return ERR_PTR(ret);
485 }
486