xref: /linux/drivers/hwtracing/coresight/coresight-tpda.c (revision 68a052239fc4b351e961f698b824f7654a346091)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2023-2025 Qualcomm Innovation Center, Inc. All rights reserved.
4  */
5 
6 #include <linux/amba/bus.h>
7 #include <linux/bitfield.h>
8 #include <linux/coresight.h>
9 #include <linux/device.h>
10 #include <linux/err.h>
11 #include <linux/fs.h>
12 #include <linux/io.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/of.h>
16 #include <linux/platform_device.h>
17 
18 #include "coresight-priv.h"
19 #include "coresight-tpda.h"
20 #include "coresight-trace-id.h"
21 #include "coresight-tpdm.h"
22 
23 DEFINE_CORESIGHT_DEVLIST(tpda_devs, "tpda");
24 
25 static bool coresight_device_is_tpdm(struct coresight_device *csdev)
26 {
27 	return (coresight_is_device_source(csdev)) &&
28 	       (csdev->subtype.source_subtype ==
29 			CORESIGHT_DEV_SUBTYPE_SOURCE_TPDM);
30 }
31 
32 static void tpda_clear_element_size(struct coresight_device *csdev)
33 {
34 	struct tpda_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
35 
36 	drvdata->dsb_esize = 0;
37 	drvdata->cmb_esize = 0;
38 }
39 
40 static void tpda_set_element_size(struct tpda_drvdata *drvdata, u32 *val)
41 {
42 	/* Clear all relevant fields */
43 	*val &= ~(TPDA_Pn_CR_DSBSIZE | TPDA_Pn_CR_CMBSIZE);
44 
45 	if (drvdata->dsb_esize == 64)
46 		*val |= TPDA_Pn_CR_DSBSIZE;
47 	else if (drvdata->dsb_esize == 32)
48 		*val &= ~TPDA_Pn_CR_DSBSIZE;
49 
50 	if (drvdata->cmb_esize == 64)
51 		*val |= FIELD_PREP(TPDA_Pn_CR_CMBSIZE, 0x2);
52 	else if (drvdata->cmb_esize == 32)
53 		*val |= FIELD_PREP(TPDA_Pn_CR_CMBSIZE, 0x1);
54 	else if (drvdata->cmb_esize == 8)
55 		*val &= ~TPDA_Pn_CR_CMBSIZE;
56 }
57 
58 /*
59  * Read the element size from the TPDM device. One TPDM must have at least one of the
60  * element size property.
61  * Returns
62  *    0 - The element size property is read
63  *    Others - Cannot read the property of the element size
64  */
65 static int tpdm_read_element_size(struct tpda_drvdata *drvdata,
66 				  struct coresight_device *csdev)
67 {
68 	int rc = -EINVAL;
69 	struct tpdm_drvdata *tpdm_data = dev_get_drvdata(csdev->dev.parent);
70 
71 	if (tpdm_data->dsb) {
72 		rc = fwnode_property_read_u32(dev_fwnode(csdev->dev.parent),
73 				"qcom,dsb-element-bits", &drvdata->dsb_esize);
74 		if (rc)
75 			goto out;
76 	}
77 
78 	if (tpdm_data->cmb) {
79 		rc = fwnode_property_read_u32(dev_fwnode(csdev->dev.parent),
80 				"qcom,cmb-element-bits", &drvdata->cmb_esize);
81 	}
82 
83 out:
84 	if (rc)
85 		dev_warn_once(&csdev->dev,
86 			"Failed to read TPDM Element size: %d\n", rc);
87 
88 	return rc;
89 }
90 
91 /*
92  * Search and read element data size from the TPDM node in
93  * the devicetree. Each input port of TPDA is connected to
94  * a TPDM. Different TPDM supports different types of dataset,
95  * and some may support more than one type of dataset.
96  * Parameter "inport" is used to pass in the input port number
97  * of TPDA, and it is set to -1 in the recursize call.
98  */
99 static int tpda_get_element_size(struct tpda_drvdata *drvdata,
100 				 struct coresight_device *csdev,
101 				 int inport)
102 {
103 	int rc = 0;
104 	int i;
105 	struct coresight_device *in;
106 
107 	for (i = 0; i < csdev->pdata->nr_inconns; i++) {
108 		in = csdev->pdata->in_conns[i]->src_dev;
109 		if (!in)
110 			continue;
111 
112 		/* Ignore the paths that do not match port */
113 		if (inport >= 0 &&
114 		    csdev->pdata->in_conns[i]->dest_port != inport)
115 			continue;
116 
117 		/*
118 		 * If this port has a hardcoded filter, use the source
119 		 * device directly.
120 		 */
121 		if (csdev->pdata->in_conns[i]->filter_src_fwnode) {
122 			in = csdev->pdata->in_conns[i]->filter_src_dev;
123 			if (!in)
124 				continue;
125 		}
126 
127 		if (coresight_device_is_tpdm(in)) {
128 			if (drvdata->dsb_esize || drvdata->cmb_esize)
129 				return -EEXIST;
130 			rc = tpdm_read_element_size(drvdata, in);
131 			if (rc)
132 				return rc;
133 		} else {
134 			/* Recurse down the path */
135 			rc = tpda_get_element_size(drvdata, in, -1);
136 			if (rc)
137 				return rc;
138 		}
139 	}
140 
141 	return rc;
142 }
143 
144 /* Settings pre enabling port control register */
145 static void tpda_enable_pre_port(struct tpda_drvdata *drvdata)
146 {
147 	u32 val;
148 
149 	val = readl_relaxed(drvdata->base + TPDA_CR);
150 	val &= ~TPDA_CR_ATID;
151 	val |= FIELD_PREP(TPDA_CR_ATID, drvdata->atid);
152 	writel_relaxed(val, drvdata->base + TPDA_CR);
153 }
154 
155 static int tpda_enable_port(struct tpda_drvdata *drvdata, int port)
156 {
157 	u32 val;
158 	int rc;
159 
160 	val = readl_relaxed(drvdata->base + TPDA_Pn_CR(port));
161 	tpda_clear_element_size(drvdata->csdev);
162 	rc = tpda_get_element_size(drvdata, drvdata->csdev, port);
163 	if (!rc && (drvdata->dsb_esize || drvdata->cmb_esize)) {
164 		tpda_set_element_size(drvdata, &val);
165 		/* Enable the port */
166 		val |= TPDA_Pn_CR_ENA;
167 		writel_relaxed(val, drvdata->base + TPDA_Pn_CR(port));
168 	} else if (rc == -EEXIST)
169 		dev_warn_once(&drvdata->csdev->dev,
170 			      "Detected multiple TPDMs on port %d", port);
171 	else
172 		dev_warn_once(&drvdata->csdev->dev,
173 			      "Didn't find TPDM element size");
174 
175 	return rc;
176 }
177 
178 static int __tpda_enable(struct tpda_drvdata *drvdata, int port)
179 {
180 	int ret;
181 
182 	CS_UNLOCK(drvdata->base);
183 
184 	/*
185 	 * Only do pre-port enable for first port that calls enable when the
186 	 * device's main refcount is still 0
187 	 */
188 	lockdep_assert_held(&drvdata->spinlock);
189 	if (!drvdata->csdev->refcnt)
190 		tpda_enable_pre_port(drvdata);
191 
192 	ret = tpda_enable_port(drvdata, port);
193 	CS_LOCK(drvdata->base);
194 
195 	return ret;
196 }
197 
198 static int tpda_enable(struct coresight_device *csdev,
199 		       struct coresight_connection *in,
200 		       struct coresight_connection *out)
201 {
202 	struct tpda_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
203 	int ret = 0;
204 
205 	spin_lock(&drvdata->spinlock);
206 	if (in->dest_refcnt == 0) {
207 		ret = __tpda_enable(drvdata, in->dest_port);
208 		if (!ret) {
209 			in->dest_refcnt++;
210 			csdev->refcnt++;
211 			dev_dbg(drvdata->dev, "TPDA inport %d enabled.\n", in->dest_port);
212 		}
213 	}
214 
215 	spin_unlock(&drvdata->spinlock);
216 	return ret;
217 }
218 
219 static void __tpda_disable(struct tpda_drvdata *drvdata, int port)
220 {
221 	u32 val;
222 
223 	CS_UNLOCK(drvdata->base);
224 
225 	val = readl_relaxed(drvdata->base + TPDA_Pn_CR(port));
226 	val &= ~TPDA_Pn_CR_ENA;
227 	writel_relaxed(val, drvdata->base + TPDA_Pn_CR(port));
228 
229 	CS_LOCK(drvdata->base);
230 }
231 
232 static void tpda_disable(struct coresight_device *csdev,
233 			 struct coresight_connection *in,
234 			 struct coresight_connection *out)
235 {
236 	struct tpda_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
237 
238 	spin_lock(&drvdata->spinlock);
239 	if (--in->dest_refcnt == 0) {
240 		__tpda_disable(drvdata, in->dest_port);
241 		csdev->refcnt--;
242 	}
243 	spin_unlock(&drvdata->spinlock);
244 
245 	dev_dbg(drvdata->dev, "TPDA inport %d disabled\n", in->dest_port);
246 }
247 
248 static int tpda_trace_id(struct coresight_device *csdev, __maybe_unused enum cs_mode mode,
249 			 __maybe_unused struct coresight_device *sink)
250 {
251 	struct tpda_drvdata *drvdata;
252 
253 	drvdata = dev_get_drvdata(csdev->dev.parent);
254 
255 	return drvdata->atid;
256 }
257 
258 static const struct coresight_ops_link tpda_link_ops = {
259 	.enable		= tpda_enable,
260 	.disable	= tpda_disable,
261 };
262 
263 static const struct coresight_ops tpda_cs_ops = {
264 	.trace_id	= tpda_trace_id,
265 	.link_ops	= &tpda_link_ops,
266 };
267 
268 static int tpda_init_default_data(struct tpda_drvdata *drvdata)
269 {
270 	int atid;
271 	/*
272 	 * TPDA must has a unique atid. This atid can uniquely
273 	 * identify the TPDM trace source connected to the TPDA.
274 	 * The TPDMs which are connected to same TPDA share the
275 	 * same trace-id. When TPDA does packetization, different
276 	 * port will have unique channel number for decoding.
277 	 */
278 	atid = coresight_trace_id_get_system_id();
279 	if (atid < 0)
280 		return atid;
281 
282 	drvdata->atid = atid;
283 	return 0;
284 }
285 
286 static int tpda_probe(struct amba_device *adev, const struct amba_id *id)
287 {
288 	int ret;
289 	struct device *dev = &adev->dev;
290 	struct coresight_platform_data *pdata;
291 	struct tpda_drvdata *drvdata;
292 	struct coresight_desc desc = { 0 };
293 	void __iomem *base;
294 
295 	pdata = coresight_get_platform_data(dev);
296 	if (IS_ERR(pdata))
297 		return PTR_ERR(pdata);
298 	adev->dev.platform_data = pdata;
299 
300 	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
301 	if (!drvdata)
302 		return -ENOMEM;
303 
304 	drvdata->dev = &adev->dev;
305 	dev_set_drvdata(dev, drvdata);
306 
307 	base = devm_ioremap_resource(dev, &adev->res);
308 	if (IS_ERR(base))
309 		return PTR_ERR(base);
310 	drvdata->base = base;
311 
312 	spin_lock_init(&drvdata->spinlock);
313 
314 	ret = tpda_init_default_data(drvdata);
315 	if (ret)
316 		return ret;
317 
318 	desc.name = coresight_alloc_device_name(&tpda_devs, dev);
319 	if (!desc.name)
320 		return -ENOMEM;
321 	desc.type = CORESIGHT_DEV_TYPE_LINK;
322 	desc.subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_MERG;
323 	desc.ops = &tpda_cs_ops;
324 	desc.pdata = adev->dev.platform_data;
325 	desc.dev = &adev->dev;
326 	desc.access = CSDEV_ACCESS_IOMEM(base);
327 	drvdata->csdev = coresight_register(&desc);
328 	if (IS_ERR(drvdata->csdev))
329 		return PTR_ERR(drvdata->csdev);
330 
331 	pm_runtime_put(&adev->dev);
332 
333 	dev_dbg(drvdata->dev, "TPDA initialized\n");
334 	return 0;
335 }
336 
337 static void tpda_remove(struct amba_device *adev)
338 {
339 	struct tpda_drvdata *drvdata = dev_get_drvdata(&adev->dev);
340 
341 	coresight_trace_id_put_system_id(drvdata->atid);
342 	coresight_unregister(drvdata->csdev);
343 }
344 
345 /*
346  * Different TPDA has different periph id.
347  * The difference is 0-7 bits' value. So ignore 0-7 bits.
348  */
349 static const struct amba_id tpda_ids[] = {
350 	{
351 		.id     = 0x000f0f00,
352 		.mask   = 0x000fff00,
353 	},
354 	{ 0, 0, NULL },
355 };
356 
357 static struct amba_driver tpda_driver = {
358 	.drv = {
359 		.name   = "coresight-tpda",
360 		.suppress_bind_attrs = true,
361 	},
362 	.probe          = tpda_probe,
363 	.remove		= tpda_remove,
364 	.id_table	= tpda_ids,
365 };
366 
367 module_amba_driver(tpda_driver);
368 
369 MODULE_LICENSE("GPL");
370 MODULE_DESCRIPTION("Trace, Profiling & Diagnostic Aggregator driver");
371