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 DEFINE_CORESIGHT_DEVLIST(replicator_devs, "replicator");
28 
29 /**
30  * struct replicator_drvdata - specifics associated to a replicator component
31  * @base:	memory mapped base address for this component. Also indicates
32  *		whether this one is programmable or not.
33  * @atclk:	optional clock for the core parts of the replicator.
34  * @csdev:	component vitals needed by the framework
35  * @spinlock:	serialize enable/disable operations.
36  * @check_idfilter_val: check if the context is lost upon clock removal.
37  */
38 struct replicator_drvdata {
39 	void __iomem		*base;
40 	struct clk		*atclk;
41 	struct coresight_device	*csdev;
42 	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 inline 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, int inport,
118 			     int outport)
119 {
120 	int rc = 0;
121 	struct replicator_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
122 	unsigned long flags;
123 	bool first_enable = false;
124 
125 	spin_lock_irqsave(&drvdata->spinlock, flags);
126 	if (atomic_read(&csdev->refcnt[outport]) == 0) {
127 		if (drvdata->base)
128 			rc = dynamic_replicator_enable(drvdata, inport,
129 						       outport);
130 		if (!rc)
131 			first_enable = true;
132 	}
133 	if (!rc)
134 		atomic_inc(&csdev->refcnt[outport]);
135 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
136 
137 	if (first_enable)
138 		dev_dbg(&csdev->dev, "REPLICATOR enabled\n");
139 	return rc;
140 }
141 
142 static void dynamic_replicator_disable(struct replicator_drvdata *drvdata,
143 				       int inport, int outport)
144 {
145 	u32 reg;
146 	struct coresight_device *csdev = drvdata->csdev;
147 
148 	switch (outport) {
149 	case 0:
150 		reg = REPLICATOR_IDFILTER0;
151 		break;
152 	case 1:
153 		reg = REPLICATOR_IDFILTER1;
154 		break;
155 	default:
156 		WARN_ON(1);
157 		return;
158 	}
159 
160 	CS_UNLOCK(drvdata->base);
161 
162 	/* disable the flow of ATB data through port */
163 	writel_relaxed(0xff, drvdata->base + reg);
164 
165 	if ((readl_relaxed(drvdata->base + REPLICATOR_IDFILTER0) == 0xff) &&
166 	    (readl_relaxed(drvdata->base + REPLICATOR_IDFILTER1) == 0xff))
167 		coresight_disclaim_device_unlocked(csdev);
168 	CS_LOCK(drvdata->base);
169 }
170 
171 static void replicator_disable(struct coresight_device *csdev, int inport,
172 			       int outport)
173 {
174 	struct replicator_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
175 	unsigned long flags;
176 	bool last_disable = false;
177 
178 	spin_lock_irqsave(&drvdata->spinlock, flags);
179 	if (atomic_dec_return(&csdev->refcnt[outport]) == 0) {
180 		if (drvdata->base)
181 			dynamic_replicator_disable(drvdata, inport, outport);
182 		last_disable = true;
183 	}
184 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
185 
186 	if (last_disable)
187 		dev_dbg(&csdev->dev, "REPLICATOR disabled\n");
188 }
189 
190 static const struct coresight_ops_link replicator_link_ops = {
191 	.enable		= replicator_enable,
192 	.disable	= replicator_disable,
193 };
194 
195 static const struct coresight_ops replicator_cs_ops = {
196 	.link_ops	= &replicator_link_ops,
197 };
198 
199 #define coresight_replicator_reg(name, offset) \
200 	coresight_simple_reg32(struct replicator_drvdata, name, offset)
201 
202 coresight_replicator_reg(idfilter0, REPLICATOR_IDFILTER0);
203 coresight_replicator_reg(idfilter1, REPLICATOR_IDFILTER1);
204 
205 static struct attribute *replicator_mgmt_attrs[] = {
206 	&dev_attr_idfilter0.attr,
207 	&dev_attr_idfilter1.attr,
208 	NULL,
209 };
210 
211 static const struct attribute_group replicator_mgmt_group = {
212 	.attrs = replicator_mgmt_attrs,
213 	.name = "mgmt",
214 };
215 
216 static const struct attribute_group *replicator_groups[] = {
217 	&replicator_mgmt_group,
218 	NULL,
219 };
220 
221 static int replicator_probe(struct device *dev, struct resource *res)
222 {
223 	int ret = 0;
224 	struct coresight_platform_data *pdata = NULL;
225 	struct replicator_drvdata *drvdata;
226 	struct coresight_desc desc = { 0 };
227 	void __iomem *base;
228 
229 	if (is_of_node(dev_fwnode(dev)) &&
230 	    of_device_is_compatible(dev->of_node, "arm,coresight-replicator"))
231 		dev_warn_once(dev,
232 			      "Uses OBSOLETE CoreSight replicator binding\n");
233 
234 	desc.name = coresight_alloc_device_name(&replicator_devs, dev);
235 	if (!desc.name)
236 		return -ENOMEM;
237 
238 	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
239 	if (!drvdata)
240 		return -ENOMEM;
241 
242 	drvdata->atclk = devm_clk_get(dev, "atclk"); /* optional */
243 	if (!IS_ERR(drvdata->atclk)) {
244 		ret = clk_prepare_enable(drvdata->atclk);
245 		if (ret)
246 			return ret;
247 	}
248 
249 	/*
250 	 * Map the device base for dynamic-replicator, which has been
251 	 * validated by AMBA core
252 	 */
253 	if (res) {
254 		base = devm_ioremap_resource(dev, res);
255 		if (IS_ERR(base)) {
256 			ret = PTR_ERR(base);
257 			goto out_disable_clk;
258 		}
259 		drvdata->base = base;
260 		desc.groups = replicator_groups;
261 		desc.access = CSDEV_ACCESS_IOMEM(base);
262 	}
263 
264 	if (fwnode_property_present(dev_fwnode(dev),
265 				    "qcom,replicator-loses-context"))
266 		drvdata->check_idfilter_val = true;
267 
268 	dev_set_drvdata(dev, drvdata);
269 
270 	pdata = coresight_get_platform_data(dev);
271 	if (IS_ERR(pdata)) {
272 		ret = PTR_ERR(pdata);
273 		goto out_disable_clk;
274 	}
275 	dev->platform_data = pdata;
276 
277 	spin_lock_init(&drvdata->spinlock);
278 	desc.type = CORESIGHT_DEV_TYPE_LINK;
279 	desc.subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_SPLIT;
280 	desc.ops = &replicator_cs_ops;
281 	desc.pdata = dev->platform_data;
282 	desc.dev = dev;
283 
284 	drvdata->csdev = coresight_register(&desc);
285 	if (IS_ERR(drvdata->csdev)) {
286 		ret = PTR_ERR(drvdata->csdev);
287 		goto out_disable_clk;
288 	}
289 
290 	replicator_reset(drvdata);
291 	pm_runtime_put(dev);
292 
293 out_disable_clk:
294 	if (ret && !IS_ERR_OR_NULL(drvdata->atclk))
295 		clk_disable_unprepare(drvdata->atclk);
296 	return ret;
297 }
298 
299 static int replicator_remove(struct device *dev)
300 {
301 	struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
302 
303 	coresight_unregister(drvdata->csdev);
304 	return 0;
305 }
306 
307 static int static_replicator_probe(struct platform_device *pdev)
308 {
309 	int ret;
310 
311 	pm_runtime_get_noresume(&pdev->dev);
312 	pm_runtime_set_active(&pdev->dev);
313 	pm_runtime_enable(&pdev->dev);
314 
315 	/* Static replicators do not have programming base */
316 	ret = replicator_probe(&pdev->dev, NULL);
317 
318 	if (ret) {
319 		pm_runtime_put_noidle(&pdev->dev);
320 		pm_runtime_disable(&pdev->dev);
321 	}
322 
323 	return ret;
324 }
325 
326 static int static_replicator_remove(struct platform_device *pdev)
327 {
328 	replicator_remove(&pdev->dev);
329 	pm_runtime_disable(&pdev->dev);
330 	return 0;
331 }
332 
333 #ifdef CONFIG_PM
334 static int replicator_runtime_suspend(struct device *dev)
335 {
336 	struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
337 
338 	if (drvdata && !IS_ERR(drvdata->atclk))
339 		clk_disable_unprepare(drvdata->atclk);
340 
341 	return 0;
342 }
343 
344 static int replicator_runtime_resume(struct device *dev)
345 {
346 	struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
347 
348 	if (drvdata && !IS_ERR(drvdata->atclk))
349 		clk_prepare_enable(drvdata->atclk);
350 
351 	return 0;
352 }
353 #endif
354 
355 static const struct dev_pm_ops replicator_dev_pm_ops = {
356 	SET_RUNTIME_PM_OPS(replicator_runtime_suspend,
357 			   replicator_runtime_resume, NULL)
358 };
359 
360 static const struct of_device_id static_replicator_match[] = {
361 	{.compatible = "arm,coresight-replicator"},
362 	{.compatible = "arm,coresight-static-replicator"},
363 	{}
364 };
365 
366 MODULE_DEVICE_TABLE(of, static_replicator_match);
367 
368 #ifdef CONFIG_ACPI
369 static const struct acpi_device_id static_replicator_acpi_ids[] = {
370 	{"ARMHC985", 0}, /* ARM CoreSight Static Replicator */
371 	{}
372 };
373 
374 MODULE_DEVICE_TABLE(acpi, static_replicator_acpi_ids);
375 #endif
376 
377 static struct platform_driver static_replicator_driver = {
378 	.probe          = static_replicator_probe,
379 	.remove         = static_replicator_remove,
380 	.driver         = {
381 		.name   = "coresight-static-replicator",
382 		/* THIS_MODULE is taken care of by platform_driver_register() */
383 		.of_match_table = of_match_ptr(static_replicator_match),
384 		.acpi_match_table = ACPI_PTR(static_replicator_acpi_ids),
385 		.pm	= &replicator_dev_pm_ops,
386 		.suppress_bind_attrs = true,
387 	},
388 };
389 
390 static int dynamic_replicator_probe(struct amba_device *adev,
391 				    const struct amba_id *id)
392 {
393 	return replicator_probe(&adev->dev, &adev->res);
394 }
395 
396 static void dynamic_replicator_remove(struct amba_device *adev)
397 {
398 	replicator_remove(&adev->dev);
399 }
400 
401 static const struct amba_id dynamic_replicator_ids[] = {
402 	CS_AMBA_ID(0x000bb909),
403 	CS_AMBA_ID(0x000bb9ec),		/* Coresight SoC-600 */
404 	{},
405 };
406 
407 MODULE_DEVICE_TABLE(amba, dynamic_replicator_ids);
408 
409 static struct amba_driver dynamic_replicator_driver = {
410 	.drv = {
411 		.name	= "coresight-dynamic-replicator",
412 		.pm	= &replicator_dev_pm_ops,
413 		.owner	= THIS_MODULE,
414 		.suppress_bind_attrs = true,
415 	},
416 	.probe		= dynamic_replicator_probe,
417 	.remove         = dynamic_replicator_remove,
418 	.id_table	= dynamic_replicator_ids,
419 };
420 
421 static int __init replicator_init(void)
422 {
423 	int ret;
424 
425 	ret = platform_driver_register(&static_replicator_driver);
426 	if (ret) {
427 		pr_info("Error registering platform driver\n");
428 		return ret;
429 	}
430 
431 	ret = amba_driver_register(&dynamic_replicator_driver);
432 	if (ret) {
433 		pr_info("Error registering amba driver\n");
434 		platform_driver_unregister(&static_replicator_driver);
435 	}
436 
437 	return ret;
438 }
439 
440 static void __exit replicator_exit(void)
441 {
442 	platform_driver_unregister(&static_replicator_driver);
443 	amba_driver_unregister(&dynamic_replicator_driver);
444 }
445 
446 module_init(replicator_init);
447 module_exit(replicator_exit);
448 
449 MODULE_AUTHOR("Pratik Patel <pratikp@codeaurora.org>");
450 MODULE_AUTHOR("Mathieu Poirier <mathieu.poirier@linaro.org>");
451 MODULE_DESCRIPTION("Arm CoreSight Replicator Driver");
452 MODULE_LICENSE("GPL v2");
453