xref: /linux/drivers/hwtracing/coresight/coresight-replicator.c (revision 53597deca0e38c30e6cd4ba2114fa42d2bcd85bb)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2011-2015, The Linux Foundation. All rights reserved.
4  *
5  * Description: CoreSight Replicator driver
6  */
7 
8 #include <linux/acpi.h>
9 #include <linux/amba/bus.h>
10 #include <linux/kernel.h>
11 #include <linux/device.h>
12 #include <linux/platform_device.h>
13 #include <linux/io.h>
14 #include <linux/err.h>
15 #include <linux/slab.h>
16 #include <linux/pm_runtime.h>
17 #include <linux/property.h>
18 #include <linux/clk.h>
19 #include <linux/of.h>
20 #include <linux/coresight.h>
21 
22 #include "coresight-priv.h"
23 
24 #define REPLICATOR_IDFILTER0		0x000
25 #define REPLICATOR_IDFILTER1		0x004
26 
27 /**
28  * struct replicator_drvdata - specifics associated to a replicator component
29  * @base:	memory mapped base address for this component. Also indicates
30  *		whether this one is programmable or not.
31  * @atclk:	optional clock for the core parts of the replicator.
32  * @pclk:	APB clock if present, otherwise NULL
33  * @csdev:	component vitals needed by the framework
34  * @spinlock:	serialize enable/disable operations.
35  * @check_idfilter_val: check if the context is lost upon clock removal.
36  */
37 struct replicator_drvdata {
38 	void __iomem		*base;
39 	struct clk		*atclk;
40 	struct clk		*pclk;
41 	struct coresight_device	*csdev;
42 	raw_spinlock_t		spinlock;
43 	bool			check_idfilter_val;
44 };
45 
46 static void dynamic_replicator_reset(struct replicator_drvdata *drvdata)
47 {
48 	struct coresight_device *csdev = drvdata->csdev;
49 
50 	CS_UNLOCK(drvdata->base);
51 
52 	if (!coresight_claim_device_unlocked(csdev)) {
53 		writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER0);
54 		writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER1);
55 		coresight_disclaim_device_unlocked(csdev);
56 	}
57 
58 	CS_LOCK(drvdata->base);
59 }
60 
61 /*
62  * replicator_reset : Reset the replicator configuration to sane values.
63  */
64 static void replicator_reset(struct replicator_drvdata *drvdata)
65 {
66 	if (drvdata->base)
67 		dynamic_replicator_reset(drvdata);
68 }
69 
70 static int dynamic_replicator_enable(struct replicator_drvdata *drvdata,
71 				     int inport, int outport)
72 {
73 	int rc = 0;
74 	u32 id0val, id1val;
75 	struct coresight_device *csdev = drvdata->csdev;
76 
77 	CS_UNLOCK(drvdata->base);
78 
79 	id0val = readl_relaxed(drvdata->base + REPLICATOR_IDFILTER0);
80 	id1val = readl_relaxed(drvdata->base + REPLICATOR_IDFILTER1);
81 
82 	/*
83 	 * Some replicator designs lose context when AMBA clocks are removed,
84 	 * so have a check for this.
85 	 */
86 	if (drvdata->check_idfilter_val && id0val == 0x0 && id1val == 0x0)
87 		id0val = id1val = 0xff;
88 
89 	if (id0val == 0xff && id1val == 0xff)
90 		rc = coresight_claim_device_unlocked(csdev);
91 
92 	if (!rc) {
93 		switch (outport) {
94 		case 0:
95 			id0val = 0x0;
96 			break;
97 		case 1:
98 			id1val = 0x0;
99 			break;
100 		default:
101 			WARN_ON(1);
102 			rc = -EINVAL;
103 		}
104 	}
105 
106 	/* Ensure that the outport is enabled. */
107 	if (!rc) {
108 		writel_relaxed(id0val, drvdata->base + REPLICATOR_IDFILTER0);
109 		writel_relaxed(id1val, drvdata->base + REPLICATOR_IDFILTER1);
110 	}
111 
112 	CS_LOCK(drvdata->base);
113 
114 	return rc;
115 }
116 
117 static int replicator_enable(struct coresight_device *csdev,
118 			     struct coresight_connection *in,
119 			     struct coresight_connection *out)
120 {
121 	int rc = 0;
122 	struct replicator_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
123 	unsigned long flags;
124 	bool first_enable = false;
125 
126 	raw_spin_lock_irqsave(&drvdata->spinlock, flags);
127 	if (out->src_refcnt == 0) {
128 		if (drvdata->base)
129 			rc = dynamic_replicator_enable(drvdata, in->dest_port,
130 						       out->src_port);
131 		if (!rc)
132 			first_enable = true;
133 	}
134 	if (!rc)
135 		out->src_refcnt++;
136 	raw_spin_unlock_irqrestore(&drvdata->spinlock, flags);
137 
138 	if (first_enable)
139 		dev_dbg(&csdev->dev, "REPLICATOR enabled\n");
140 	return rc;
141 }
142 
143 static void dynamic_replicator_disable(struct replicator_drvdata *drvdata,
144 				       int inport, int outport)
145 {
146 	u32 reg;
147 	struct coresight_device *csdev = drvdata->csdev;
148 
149 	switch (outport) {
150 	case 0:
151 		reg = REPLICATOR_IDFILTER0;
152 		break;
153 	case 1:
154 		reg = REPLICATOR_IDFILTER1;
155 		break;
156 	default:
157 		WARN_ON(1);
158 		return;
159 	}
160 
161 	CS_UNLOCK(drvdata->base);
162 
163 	/* disable the flow of ATB data through port */
164 	writel_relaxed(0xff, drvdata->base + reg);
165 
166 	if ((readl_relaxed(drvdata->base + REPLICATOR_IDFILTER0) == 0xff) &&
167 	    (readl_relaxed(drvdata->base + REPLICATOR_IDFILTER1) == 0xff))
168 		coresight_disclaim_device_unlocked(csdev);
169 	CS_LOCK(drvdata->base);
170 }
171 
172 static void replicator_disable(struct coresight_device *csdev,
173 			       struct coresight_connection *in,
174 			       struct coresight_connection *out)
175 {
176 	struct replicator_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
177 	unsigned long flags;
178 	bool last_disable = false;
179 
180 	raw_spin_lock_irqsave(&drvdata->spinlock, flags);
181 	if (--out->src_refcnt == 0) {
182 		if (drvdata->base)
183 			dynamic_replicator_disable(drvdata, in->dest_port,
184 						   out->src_port);
185 		last_disable = true;
186 	}
187 	raw_spin_unlock_irqrestore(&drvdata->spinlock, flags);
188 
189 	if (last_disable)
190 		dev_dbg(&csdev->dev, "REPLICATOR disabled\n");
191 }
192 
193 static const struct coresight_ops_link replicator_link_ops = {
194 	.enable		= replicator_enable,
195 	.disable	= replicator_disable,
196 };
197 
198 static const struct coresight_ops replicator_cs_ops = {
199 	.link_ops	= &replicator_link_ops,
200 };
201 
202 static struct attribute *replicator_mgmt_attrs[] = {
203 	coresight_simple_reg32(idfilter0, REPLICATOR_IDFILTER0),
204 	coresight_simple_reg32(idfilter1, REPLICATOR_IDFILTER1),
205 	NULL,
206 };
207 
208 static const struct attribute_group replicator_mgmt_group = {
209 	.attrs = replicator_mgmt_attrs,
210 	.name = "mgmt",
211 };
212 
213 static const struct attribute_group *replicator_groups[] = {
214 	&replicator_mgmt_group,
215 	NULL,
216 };
217 
218 static int replicator_probe(struct device *dev, struct resource *res)
219 {
220 	struct coresight_platform_data *pdata = NULL;
221 	struct replicator_drvdata *drvdata;
222 	struct coresight_desc desc = { 0 };
223 	void __iomem *base;
224 	int ret;
225 
226 	if (is_of_node(dev_fwnode(dev)) &&
227 	    of_device_is_compatible(dev->of_node, "arm,coresight-replicator"))
228 		dev_warn_once(dev,
229 			      "Uses OBSOLETE CoreSight replicator binding\n");
230 
231 	desc.name = coresight_alloc_device_name("replicator", dev);
232 	if (!desc.name)
233 		return -ENOMEM;
234 
235 	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
236 	if (!drvdata)
237 		return -ENOMEM;
238 
239 	ret = coresight_get_enable_clocks(dev, &drvdata->pclk, &drvdata->atclk);
240 	if (ret)
241 		return ret;
242 
243 	/*
244 	 * Map the device base for dynamic-replicator, which has been
245 	 * validated by AMBA core
246 	 */
247 	if (res) {
248 		base = devm_ioremap_resource(dev, res);
249 		if (IS_ERR(base))
250 			return PTR_ERR(base);
251 		drvdata->base = base;
252 		desc.groups = replicator_groups;
253 		desc.access = CSDEV_ACCESS_IOMEM(base);
254 		coresight_clear_self_claim_tag(&desc.access);
255 	}
256 
257 	if (fwnode_property_present(dev_fwnode(dev),
258 				    "qcom,replicator-loses-context"))
259 		drvdata->check_idfilter_val = true;
260 
261 	dev_set_drvdata(dev, drvdata);
262 
263 	pdata = coresight_get_platform_data(dev);
264 	if (IS_ERR(pdata))
265 		return PTR_ERR(pdata);
266 	dev->platform_data = pdata;
267 
268 	raw_spin_lock_init(&drvdata->spinlock);
269 	desc.type = CORESIGHT_DEV_TYPE_LINK;
270 	desc.subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_SPLIT;
271 	desc.ops = &replicator_cs_ops;
272 	desc.pdata = dev->platform_data;
273 	desc.dev = dev;
274 
275 	drvdata->csdev = coresight_register(&desc);
276 	if (IS_ERR(drvdata->csdev))
277 		return PTR_ERR(drvdata->csdev);
278 
279 	replicator_reset(drvdata);
280 	return 0;
281 }
282 
283 static int replicator_remove(struct device *dev)
284 {
285 	struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
286 
287 	coresight_unregister(drvdata->csdev);
288 	return 0;
289 }
290 
291 static int replicator_platform_probe(struct platform_device *pdev)
292 {
293 	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
294 	int ret;
295 
296 	pm_runtime_get_noresume(&pdev->dev);
297 	pm_runtime_set_active(&pdev->dev);
298 	pm_runtime_enable(&pdev->dev);
299 
300 	ret = replicator_probe(&pdev->dev, res);
301 	pm_runtime_put(&pdev->dev);
302 	if (ret)
303 		pm_runtime_disable(&pdev->dev);
304 
305 	return ret;
306 }
307 
308 static void replicator_platform_remove(struct platform_device *pdev)
309 {
310 	struct replicator_drvdata *drvdata = dev_get_drvdata(&pdev->dev);
311 
312 	if (WARN_ON(!drvdata))
313 		return;
314 
315 	replicator_remove(&pdev->dev);
316 	pm_runtime_disable(&pdev->dev);
317 }
318 
319 #ifdef CONFIG_PM
320 static int replicator_runtime_suspend(struct device *dev)
321 {
322 	struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
323 
324 	clk_disable_unprepare(drvdata->atclk);
325 	clk_disable_unprepare(drvdata->pclk);
326 
327 	return 0;
328 }
329 
330 static int replicator_runtime_resume(struct device *dev)
331 {
332 	struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
333 	int ret;
334 
335 	ret = clk_prepare_enable(drvdata->pclk);
336 	if (ret)
337 		return ret;
338 
339 	ret = clk_prepare_enable(drvdata->atclk);
340 	if (ret)
341 		clk_disable_unprepare(drvdata->pclk);
342 
343 	return ret;
344 }
345 #endif
346 
347 static const struct dev_pm_ops replicator_dev_pm_ops = {
348 	SET_RUNTIME_PM_OPS(replicator_runtime_suspend,
349 			   replicator_runtime_resume, NULL)
350 };
351 
352 static const struct of_device_id replicator_match[] = {
353 	{.compatible = "arm,coresight-replicator"},
354 	{.compatible = "arm,coresight-static-replicator"},
355 	{}
356 };
357 
358 MODULE_DEVICE_TABLE(of, replicator_match);
359 
360 #ifdef CONFIG_ACPI
361 static const struct acpi_device_id replicator_acpi_ids[] = {
362 	{"ARMHC985", 0, 0, 0}, /* ARM CoreSight Static Replicator */
363 	{"ARMHC98D", 0, 0, 0}, /* ARM CoreSight Dynamic Replicator */
364 	{}
365 };
366 
367 MODULE_DEVICE_TABLE(acpi, replicator_acpi_ids);
368 #endif
369 
370 static struct platform_driver replicator_driver = {
371 	.probe          = replicator_platform_probe,
372 	.remove         = replicator_platform_remove,
373 	.driver         = {
374 		.name   = "coresight-replicator",
375 		/* THIS_MODULE is taken care of by platform_driver_register() */
376 		.of_match_table = of_match_ptr(replicator_match),
377 		.acpi_match_table = ACPI_PTR(replicator_acpi_ids),
378 		.pm	= &replicator_dev_pm_ops,
379 		.suppress_bind_attrs = true,
380 	},
381 };
382 
383 static int dynamic_replicator_probe(struct amba_device *adev,
384 				    const struct amba_id *id)
385 {
386 	int ret;
387 
388 	ret = replicator_probe(&adev->dev, &adev->res);
389 	if (!ret)
390 		pm_runtime_put(&adev->dev);
391 
392 	return ret;
393 }
394 
395 static void dynamic_replicator_remove(struct amba_device *adev)
396 {
397 	replicator_remove(&adev->dev);
398 }
399 
400 static const struct amba_id dynamic_replicator_ids[] = {
401 	CS_AMBA_ID(0x000bb909),
402 	CS_AMBA_ID(0x000bb9ec),		/* Coresight SoC-600 */
403 	{},
404 };
405 
406 MODULE_DEVICE_TABLE(amba, dynamic_replicator_ids);
407 
408 static struct amba_driver dynamic_replicator_driver = {
409 	.drv = {
410 		.name	= "coresight-dynamic-replicator",
411 		.pm	= &replicator_dev_pm_ops,
412 		.suppress_bind_attrs = true,
413 	},
414 	.probe		= dynamic_replicator_probe,
415 	.remove         = dynamic_replicator_remove,
416 	.id_table	= dynamic_replicator_ids,
417 };
418 
419 static int __init replicator_init(void)
420 {
421 	return coresight_init_driver("replicator", &dynamic_replicator_driver, &replicator_driver,
422 				     THIS_MODULE);
423 }
424 
425 static void __exit replicator_exit(void)
426 {
427 	coresight_remove_driver(&dynamic_replicator_driver, &replicator_driver);
428 }
429 
430 module_init(replicator_init);
431 module_exit(replicator_exit);
432 
433 MODULE_AUTHOR("Pratik Patel <pratikp@codeaurora.org>");
434 MODULE_AUTHOR("Mathieu Poirier <mathieu.poirier@linaro.org>");
435 MODULE_DESCRIPTION("Arm CoreSight Replicator Driver");
436 MODULE_LICENSE("GPL v2");
437