1 /* Copyright (c) 2011-2012, The Linux Foundation. All rights reserved.
2  *
3  * This program is free software; you can redistribute it and/or modify
4  * it under the terms of the GNU General Public License version 2 and
5  * only version 2 as published by the Free Software Foundation.
6  *
7  * This program is distributed in the hope that it will be useful,
8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10  * GNU General Public License for more details.
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/types.h>
17 #include <linux/device.h>
18 #include <linux/err.h>
19 #include <linux/fs.h>
20 #include <linux/slab.h>
21 #include <linux/pm_runtime.h>
22 #include <linux/coresight.h>
23 #include <linux/amba/bus.h>
24 #include <linux/clk.h>
25 
26 #include "coresight-priv.h"
27 
28 #define FUNNEL_FUNCTL		0x000
29 #define FUNNEL_PRICTL		0x004
30 
31 #define FUNNEL_HOLDTIME_MASK	0xf00
32 #define FUNNEL_HOLDTIME_SHFT	0x8
33 #define FUNNEL_HOLDTIME		(0x7 << FUNNEL_HOLDTIME_SHFT)
34 
35 /**
36  * struct funnel_drvdata - specifics associated to a funnel component
37  * @base:	memory mapped base address for this component.
38  * @dev:	the device entity associated to this component.
39  * @atclk:	optional clock for the core parts of the funnel.
40  * @csdev:	component vitals needed by the framework.
41  * @priority:	port selection order.
42  */
43 struct funnel_drvdata {
44 	void __iomem		*base;
45 	struct device		*dev;
46 	struct clk		*atclk;
47 	struct coresight_device	*csdev;
48 	unsigned long		priority;
49 };
50 
51 static void funnel_enable_hw(struct funnel_drvdata *drvdata, int port)
52 {
53 	u32 functl;
54 
55 	CS_UNLOCK(drvdata->base);
56 
57 	functl = readl_relaxed(drvdata->base + FUNNEL_FUNCTL);
58 	functl &= ~FUNNEL_HOLDTIME_MASK;
59 	functl |= FUNNEL_HOLDTIME;
60 	functl |= (1 << port);
61 	writel_relaxed(functl, drvdata->base + FUNNEL_FUNCTL);
62 	writel_relaxed(drvdata->priority, drvdata->base + FUNNEL_PRICTL);
63 
64 	CS_LOCK(drvdata->base);
65 }
66 
67 static int funnel_enable(struct coresight_device *csdev, int inport,
68 			 int outport)
69 {
70 	struct funnel_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
71 
72 	pm_runtime_get_sync(drvdata->dev);
73 	funnel_enable_hw(drvdata, inport);
74 
75 	dev_info(drvdata->dev, "FUNNEL inport %d enabled\n", inport);
76 	return 0;
77 }
78 
79 static void funnel_disable_hw(struct funnel_drvdata *drvdata, int inport)
80 {
81 	u32 functl;
82 
83 	CS_UNLOCK(drvdata->base);
84 
85 	functl = readl_relaxed(drvdata->base + FUNNEL_FUNCTL);
86 	functl &= ~(1 << inport);
87 	writel_relaxed(functl, drvdata->base + FUNNEL_FUNCTL);
88 
89 	CS_LOCK(drvdata->base);
90 }
91 
92 static void funnel_disable(struct coresight_device *csdev, int inport,
93 			   int outport)
94 {
95 	struct funnel_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
96 
97 	funnel_disable_hw(drvdata, inport);
98 	pm_runtime_put(drvdata->dev);
99 
100 	dev_info(drvdata->dev, "FUNNEL inport %d disabled\n", inport);
101 }
102 
103 static const struct coresight_ops_link funnel_link_ops = {
104 	.enable		= funnel_enable,
105 	.disable	= funnel_disable,
106 };
107 
108 static const struct coresight_ops funnel_cs_ops = {
109 	.link_ops	= &funnel_link_ops,
110 };
111 
112 static ssize_t priority_show(struct device *dev,
113 			     struct device_attribute *attr, char *buf)
114 {
115 	struct funnel_drvdata *drvdata = dev_get_drvdata(dev->parent);
116 	unsigned long val = drvdata->priority;
117 
118 	return sprintf(buf, "%#lx\n", val);
119 }
120 
121 static ssize_t priority_store(struct device *dev,
122 			      struct device_attribute *attr,
123 			      const char *buf, size_t size)
124 {
125 	int ret;
126 	unsigned long val;
127 	struct funnel_drvdata *drvdata = dev_get_drvdata(dev->parent);
128 
129 	ret = kstrtoul(buf, 16, &val);
130 	if (ret)
131 		return ret;
132 
133 	drvdata->priority = val;
134 	return size;
135 }
136 static DEVICE_ATTR_RW(priority);
137 
138 static u32 get_funnel_ctrl_hw(struct funnel_drvdata *drvdata)
139 {
140 	u32 functl;
141 
142 	CS_UNLOCK(drvdata->base);
143 	functl = readl_relaxed(drvdata->base + FUNNEL_FUNCTL);
144 	CS_LOCK(drvdata->base);
145 
146 	return functl;
147 }
148 
149 static ssize_t funnel_ctrl_show(struct device *dev,
150 			     struct device_attribute *attr, char *buf)
151 {
152 	u32 val;
153 	struct funnel_drvdata *drvdata = dev_get_drvdata(dev->parent);
154 
155 	pm_runtime_get_sync(drvdata->dev);
156 
157 	val = get_funnel_ctrl_hw(drvdata);
158 
159 	pm_runtime_put(drvdata->dev);
160 
161 	return sprintf(buf, "%#x\n", val);
162 }
163 static DEVICE_ATTR_RO(funnel_ctrl);
164 
165 static struct attribute *coresight_funnel_attrs[] = {
166 	&dev_attr_funnel_ctrl.attr,
167 	&dev_attr_priority.attr,
168 	NULL,
169 };
170 ATTRIBUTE_GROUPS(coresight_funnel);
171 
172 static int funnel_probe(struct amba_device *adev, const struct amba_id *id)
173 {
174 	int ret;
175 	void __iomem *base;
176 	struct device *dev = &adev->dev;
177 	struct coresight_platform_data *pdata = NULL;
178 	struct funnel_drvdata *drvdata;
179 	struct resource *res = &adev->res;
180 	struct coresight_desc *desc;
181 	struct device_node *np = adev->dev.of_node;
182 
183 	if (np) {
184 		pdata = of_get_coresight_platform_data(dev, np);
185 		if (IS_ERR(pdata))
186 			return PTR_ERR(pdata);
187 		adev->dev.platform_data = pdata;
188 	}
189 
190 	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
191 	if (!drvdata)
192 		return -ENOMEM;
193 
194 	drvdata->dev = &adev->dev;
195 	drvdata->atclk = devm_clk_get(&adev->dev, "atclk"); /* optional */
196 	if (!IS_ERR(drvdata->atclk)) {
197 		ret = clk_prepare_enable(drvdata->atclk);
198 		if (ret)
199 			return ret;
200 	}
201 	dev_set_drvdata(dev, drvdata);
202 
203 	/* Validity for the resource is already checked by the AMBA core */
204 	base = devm_ioremap_resource(dev, res);
205 	if (IS_ERR(base))
206 		return PTR_ERR(base);
207 
208 	drvdata->base = base;
209 	pm_runtime_put(&adev->dev);
210 
211 	desc = devm_kzalloc(dev, sizeof(*desc), GFP_KERNEL);
212 	if (!desc)
213 		return -ENOMEM;
214 
215 	desc->type = CORESIGHT_DEV_TYPE_LINK;
216 	desc->subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_MERG;
217 	desc->ops = &funnel_cs_ops;
218 	desc->pdata = pdata;
219 	desc->dev = dev;
220 	desc->groups = coresight_funnel_groups;
221 	drvdata->csdev = coresight_register(desc);
222 	if (IS_ERR(drvdata->csdev))
223 		return PTR_ERR(drvdata->csdev);
224 
225 	dev_info(dev, "FUNNEL initialized\n");
226 	return 0;
227 }
228 
229 static int funnel_remove(struct amba_device *adev)
230 {
231 	struct funnel_drvdata *drvdata = amba_get_drvdata(adev);
232 
233 	coresight_unregister(drvdata->csdev);
234 	return 0;
235 }
236 
237 #ifdef CONFIG_PM
238 static int funnel_runtime_suspend(struct device *dev)
239 {
240 	struct funnel_drvdata *drvdata = dev_get_drvdata(dev);
241 
242 	if (drvdata && !IS_ERR(drvdata->atclk))
243 		clk_disable_unprepare(drvdata->atclk);
244 
245 	return 0;
246 }
247 
248 static int funnel_runtime_resume(struct device *dev)
249 {
250 	struct funnel_drvdata *drvdata = dev_get_drvdata(dev);
251 
252 	if (drvdata && !IS_ERR(drvdata->atclk))
253 		clk_prepare_enable(drvdata->atclk);
254 
255 	return 0;
256 }
257 #endif
258 
259 static const struct dev_pm_ops funnel_dev_pm_ops = {
260 	SET_RUNTIME_PM_OPS(funnel_runtime_suspend, funnel_runtime_resume, NULL)
261 };
262 
263 static struct amba_id funnel_ids[] = {
264 	{
265 		.id     = 0x0003b908,
266 		.mask   = 0x0003ffff,
267 	},
268 	{ 0, 0},
269 };
270 
271 static struct amba_driver funnel_driver = {
272 	.drv = {
273 		.name	= "coresight-funnel",
274 		.owner	= THIS_MODULE,
275 		.pm	= &funnel_dev_pm_ops,
276 	},
277 	.probe		= funnel_probe,
278 	.remove		= funnel_remove,
279 	.id_table	= funnel_ids,
280 };
281 
282 module_amba_driver(funnel_driver);
283 
284 MODULE_LICENSE("GPL v2");
285 MODULE_DESCRIPTION("CoreSight Funnel driver");
286