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 	CS_UNLOCK(drvdata->base);
49 
50 	if (!coresight_claim_device_unlocked(drvdata->base)) {
51 		writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER0);
52 		writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER1);
53 		coresight_disclaim_device_unlocked(drvdata->base);
54 	}
55 
56 	CS_LOCK(drvdata->base);
57 }
58 
59 /*
60  * replicator_reset : Reset the replicator configuration to sane values.
61  */
62 static inline void replicator_reset(struct replicator_drvdata *drvdata)
63 {
64 	if (drvdata->base)
65 		dynamic_replicator_reset(drvdata);
66 }
67 
68 static int dynamic_replicator_enable(struct replicator_drvdata *drvdata,
69 				     int inport, int outport)
70 {
71 	int rc = 0;
72 	u32 id0val, id1val;
73 
74 	CS_UNLOCK(drvdata->base);
75 
76 	id0val = readl_relaxed(drvdata->base + REPLICATOR_IDFILTER0);
77 	id1val = readl_relaxed(drvdata->base + REPLICATOR_IDFILTER1);
78 
79 	/*
80 	 * Some replicator designs lose context when AMBA clocks are removed,
81 	 * so have a check for this.
82 	 */
83 	if (drvdata->check_idfilter_val && id0val == 0x0 && id1val == 0x0)
84 		id0val = id1val = 0xff;
85 
86 	if (id0val == 0xff && id1val == 0xff)
87 		rc = coresight_claim_device_unlocked(drvdata->base);
88 
89 	if (!rc) {
90 		switch (outport) {
91 		case 0:
92 			id0val = 0x0;
93 			break;
94 		case 1:
95 			id1val = 0x0;
96 			break;
97 		default:
98 			WARN_ON(1);
99 			rc = -EINVAL;
100 		}
101 	}
102 
103 	/* Ensure that the outport is enabled. */
104 	if (!rc) {
105 		writel_relaxed(id0val, drvdata->base + REPLICATOR_IDFILTER0);
106 		writel_relaxed(id1val, drvdata->base + REPLICATOR_IDFILTER1);
107 	}
108 
109 	CS_LOCK(drvdata->base);
110 
111 	return rc;
112 }
113 
114 static int replicator_enable(struct coresight_device *csdev, int inport,
115 			     int outport)
116 {
117 	int rc = 0;
118 	struct replicator_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
119 	unsigned long flags;
120 	bool first_enable = false;
121 
122 	spin_lock_irqsave(&drvdata->spinlock, flags);
123 	if (atomic_read(&csdev->refcnt[outport]) == 0) {
124 		if (drvdata->base)
125 			rc = dynamic_replicator_enable(drvdata, inport,
126 						       outport);
127 		if (!rc)
128 			first_enable = true;
129 	}
130 	if (!rc)
131 		atomic_inc(&csdev->refcnt[outport]);
132 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
133 
134 	if (first_enable)
135 		dev_dbg(&csdev->dev, "REPLICATOR enabled\n");
136 	return rc;
137 }
138 
139 static void dynamic_replicator_disable(struct replicator_drvdata *drvdata,
140 				       int inport, int outport)
141 {
142 	u32 reg;
143 
144 	switch (outport) {
145 	case 0:
146 		reg = REPLICATOR_IDFILTER0;
147 		break;
148 	case 1:
149 		reg = REPLICATOR_IDFILTER1;
150 		break;
151 	default:
152 		WARN_ON(1);
153 		return;
154 	}
155 
156 	CS_UNLOCK(drvdata->base);
157 
158 	/* disable the flow of ATB data through port */
159 	writel_relaxed(0xff, drvdata->base + reg);
160 
161 	if ((readl_relaxed(drvdata->base + REPLICATOR_IDFILTER0) == 0xff) &&
162 	    (readl_relaxed(drvdata->base + REPLICATOR_IDFILTER1) == 0xff))
163 		coresight_disclaim_device_unlocked(drvdata->base);
164 	CS_LOCK(drvdata->base);
165 }
166 
167 static void replicator_disable(struct coresight_device *csdev, int inport,
168 			       int outport)
169 {
170 	struct replicator_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
171 	unsigned long flags;
172 	bool last_disable = false;
173 
174 	spin_lock_irqsave(&drvdata->spinlock, flags);
175 	if (atomic_dec_return(&csdev->refcnt[outport]) == 0) {
176 		if (drvdata->base)
177 			dynamic_replicator_disable(drvdata, inport, outport);
178 		last_disable = true;
179 	}
180 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
181 
182 	if (last_disable)
183 		dev_dbg(&csdev->dev, "REPLICATOR disabled\n");
184 }
185 
186 static const struct coresight_ops_link replicator_link_ops = {
187 	.enable		= replicator_enable,
188 	.disable	= replicator_disable,
189 };
190 
191 static const struct coresight_ops replicator_cs_ops = {
192 	.link_ops	= &replicator_link_ops,
193 };
194 
195 #define coresight_replicator_reg(name, offset) \
196 	coresight_simple_reg32(struct replicator_drvdata, name, offset)
197 
198 coresight_replicator_reg(idfilter0, REPLICATOR_IDFILTER0);
199 coresight_replicator_reg(idfilter1, REPLICATOR_IDFILTER1);
200 
201 static struct attribute *replicator_mgmt_attrs[] = {
202 	&dev_attr_idfilter0.attr,
203 	&dev_attr_idfilter1.attr,
204 	NULL,
205 };
206 
207 static const struct attribute_group replicator_mgmt_group = {
208 	.attrs = replicator_mgmt_attrs,
209 	.name = "mgmt",
210 };
211 
212 static const struct attribute_group *replicator_groups[] = {
213 	&replicator_mgmt_group,
214 	NULL,
215 };
216 
217 static int replicator_probe(struct device *dev, struct resource *res)
218 {
219 	int ret = 0;
220 	struct coresight_platform_data *pdata = NULL;
221 	struct replicator_drvdata *drvdata;
222 	struct coresight_desc desc = { 0 };
223 	void __iomem *base;
224 
225 	if (is_of_node(dev_fwnode(dev)) &&
226 	    of_device_is_compatible(dev->of_node, "arm,coresight-replicator"))
227 		dev_warn_once(dev,
228 			      "Uses OBSOLETE CoreSight replicator binding\n");
229 
230 	desc.name = coresight_alloc_device_name(&replicator_devs, dev);
231 	if (!desc.name)
232 		return -ENOMEM;
233 
234 	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
235 	if (!drvdata)
236 		return -ENOMEM;
237 
238 	drvdata->atclk = devm_clk_get(dev, "atclk"); /* optional */
239 	if (!IS_ERR(drvdata->atclk)) {
240 		ret = clk_prepare_enable(drvdata->atclk);
241 		if (ret)
242 			return ret;
243 	}
244 
245 	/*
246 	 * Map the device base for dynamic-replicator, which has been
247 	 * validated by AMBA core
248 	 */
249 	if (res) {
250 		base = devm_ioremap_resource(dev, res);
251 		if (IS_ERR(base)) {
252 			ret = PTR_ERR(base);
253 			goto out_disable_clk;
254 		}
255 		drvdata->base = base;
256 		desc.groups = replicator_groups;
257 	}
258 
259 	if (fwnode_property_present(dev_fwnode(dev),
260 				    "qcom,replicator-loses-context"))
261 		drvdata->check_idfilter_val = true;
262 
263 	dev_set_drvdata(dev, drvdata);
264 
265 	pdata = coresight_get_platform_data(dev);
266 	if (IS_ERR(pdata)) {
267 		ret = PTR_ERR(pdata);
268 		goto out_disable_clk;
269 	}
270 	dev->platform_data = pdata;
271 
272 	spin_lock_init(&drvdata->spinlock);
273 	desc.type = CORESIGHT_DEV_TYPE_LINK;
274 	desc.subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_SPLIT;
275 	desc.ops = &replicator_cs_ops;
276 	desc.pdata = dev->platform_data;
277 	desc.dev = dev;
278 
279 	drvdata->csdev = coresight_register(&desc);
280 	if (IS_ERR(drvdata->csdev)) {
281 		ret = PTR_ERR(drvdata->csdev);
282 		goto out_disable_clk;
283 	}
284 
285 	replicator_reset(drvdata);
286 	pm_runtime_put(dev);
287 
288 out_disable_clk:
289 	if (ret && !IS_ERR_OR_NULL(drvdata->atclk))
290 		clk_disable_unprepare(drvdata->atclk);
291 	return ret;
292 }
293 
294 static int static_replicator_probe(struct platform_device *pdev)
295 {
296 	int ret;
297 
298 	pm_runtime_get_noresume(&pdev->dev);
299 	pm_runtime_set_active(&pdev->dev);
300 	pm_runtime_enable(&pdev->dev);
301 
302 	/* Static replicators do not have programming base */
303 	ret = replicator_probe(&pdev->dev, NULL);
304 
305 	if (ret) {
306 		pm_runtime_put_noidle(&pdev->dev);
307 		pm_runtime_disable(&pdev->dev);
308 	}
309 
310 	return ret;
311 }
312 
313 #ifdef CONFIG_PM
314 static int replicator_runtime_suspend(struct device *dev)
315 {
316 	struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
317 
318 	if (drvdata && !IS_ERR(drvdata->atclk))
319 		clk_disable_unprepare(drvdata->atclk);
320 
321 	return 0;
322 }
323 
324 static int replicator_runtime_resume(struct device *dev)
325 {
326 	struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
327 
328 	if (drvdata && !IS_ERR(drvdata->atclk))
329 		clk_prepare_enable(drvdata->atclk);
330 
331 	return 0;
332 }
333 #endif
334 
335 static const struct dev_pm_ops replicator_dev_pm_ops = {
336 	SET_RUNTIME_PM_OPS(replicator_runtime_suspend,
337 			   replicator_runtime_resume, NULL)
338 };
339 
340 static const struct of_device_id static_replicator_match[] = {
341 	{.compatible = "arm,coresight-replicator"},
342 	{.compatible = "arm,coresight-static-replicator"},
343 	{}
344 };
345 
346 #ifdef CONFIG_ACPI
347 static const struct acpi_device_id static_replicator_acpi_ids[] = {
348 	{"ARMHC985", 0}, /* ARM CoreSight Static Replicator */
349 	{}
350 };
351 #endif
352 
353 static struct platform_driver static_replicator_driver = {
354 	.probe          = static_replicator_probe,
355 	.driver         = {
356 		.name   = "coresight-static-replicator",
357 		.of_match_table = of_match_ptr(static_replicator_match),
358 		.acpi_match_table = ACPI_PTR(static_replicator_acpi_ids),
359 		.pm	= &replicator_dev_pm_ops,
360 		.suppress_bind_attrs = true,
361 	},
362 };
363 builtin_platform_driver(static_replicator_driver);
364 
365 static int dynamic_replicator_probe(struct amba_device *adev,
366 				    const struct amba_id *id)
367 {
368 	return replicator_probe(&adev->dev, &adev->res);
369 }
370 
371 static const struct amba_id dynamic_replicator_ids[] = {
372 	CS_AMBA_ID(0x000bb909),
373 	CS_AMBA_ID(0x000bb9ec),		/* Coresight SoC-600 */
374 	{},
375 };
376 
377 static struct amba_driver dynamic_replicator_driver = {
378 	.drv = {
379 		.name	= "coresight-dynamic-replicator",
380 		.pm	= &replicator_dev_pm_ops,
381 		.suppress_bind_attrs = true,
382 	},
383 	.probe		= dynamic_replicator_probe,
384 	.id_table	= dynamic_replicator_ids,
385 };
386 builtin_amba_driver(dynamic_replicator_driver);
387