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 */
43struct 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
51static 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
67static 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
79static 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
92static 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
103static const struct coresight_ops_link funnel_link_ops = {
104	.enable		= funnel_enable,
105	.disable	= funnel_disable,
106};
107
108static const struct coresight_ops funnel_cs_ops = {
109	.link_ops	= &funnel_link_ops,
110};
111
112static 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
121static 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}
136static DEVICE_ATTR_RW(priority);
137
138static 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
149static 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}
163static DEVICE_ATTR_RO(funnel_ctrl);
164
165static struct attribute *coresight_funnel_attrs[] = {
166	&dev_attr_funnel_ctrl.attr,
167	&dev_attr_priority.attr,
168	NULL,
169};
170ATTRIBUTE_GROUPS(coresight_funnel);
171
172static 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
229static 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
238static 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
248static 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
259static const struct dev_pm_ops funnel_dev_pm_ops = {
260	SET_RUNTIME_PM_OPS(funnel_runtime_suspend, funnel_runtime_resume, NULL)
261};
262
263static struct amba_id funnel_ids[] = {
264	{
265		.id     = 0x0003b908,
266		.mask   = 0x0003ffff,
267	},
268	{ 0, 0},
269};
270
271static 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
282module_amba_driver(funnel_driver);
283
284MODULE_LICENSE("GPL v2");
285MODULE_DESCRIPTION("CoreSight Funnel driver");
286