1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Intel(R) Trace Hub PTI output driver
4 *
5 * Copyright (C) 2014-2016 Intel Corporation.
6 */
7
8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
10#include <linux/types.h>
11#include <linux/module.h>
12#include <linux/device.h>
13#include <linux/sizes.h>
14#include <linux/printk.h>
15#include <linux/slab.h>
16#include <linux/mm.h>
17#include <linux/io.h>
18
19#include "intel_th.h"
20#include "pti.h"
21
22struct pti_device {
23 void __iomem *base;
24 struct intel_th_device *thdev;
25 unsigned int mode;
26 unsigned int freeclk;
27 unsigned int clkdiv;
28 unsigned int patgen;
29 unsigned int lpp_dest_mask;
30 unsigned int lpp_dest;
31};
32
33/* map PTI widths to MODE settings of PTI_CTL register */
34static const unsigned int pti_mode[] = {
35 0, 4, 8, 0, 12, 0, 0, 0, 16, 0, 0, 0, 0, 0, 0, 0,
36};
37
38static int pti_width_mode(unsigned int width)
39{
40 int i;
41
42 for (i = 0; i < ARRAY_SIZE(pti_mode); i++)
43 if (pti_mode[i] == width)
44 return i;
45
46 return -EINVAL;
47}
48
49static ssize_t mode_show(struct device *dev, struct device_attribute *attr,
50 char *buf)
51{
52 struct pti_device *pti = dev_get_drvdata(dev);
53
54 return scnprintf(buf, PAGE_SIZE, fmt: "%d\n", pti_mode[pti->mode]);
55}
56
57static ssize_t mode_store(struct device *dev, struct device_attribute *attr,
58 const char *buf, size_t size)
59{
60 struct pti_device *pti = dev_get_drvdata(dev);
61 unsigned long val;
62 int ret;
63
64 ret = kstrtoul(s: buf, base: 10, res: &val);
65 if (ret)
66 return ret;
67
68 ret = pti_width_mode(width: val);
69 if (ret < 0)
70 return ret;
71
72 pti->mode = ret;
73
74 return size;
75}
76
77static DEVICE_ATTR_RW(mode);
78
79static ssize_t
80freerunning_clock_show(struct device *dev, struct device_attribute *attr,
81 char *buf)
82{
83 struct pti_device *pti = dev_get_drvdata(dev);
84
85 return scnprintf(buf, PAGE_SIZE, fmt: "%d\n", pti->freeclk);
86}
87
88static ssize_t
89freerunning_clock_store(struct device *dev, struct device_attribute *attr,
90 const char *buf, size_t size)
91{
92 struct pti_device *pti = dev_get_drvdata(dev);
93 unsigned long val;
94 int ret;
95
96 ret = kstrtoul(s: buf, base: 10, res: &val);
97 if (ret)
98 return ret;
99
100 pti->freeclk = !!val;
101
102 return size;
103}
104
105static DEVICE_ATTR_RW(freerunning_clock);
106
107static ssize_t
108clock_divider_show(struct device *dev, struct device_attribute *attr,
109 char *buf)
110{
111 struct pti_device *pti = dev_get_drvdata(dev);
112
113 return scnprintf(buf, PAGE_SIZE, fmt: "%d\n", 1u << pti->clkdiv);
114}
115
116static ssize_t
117clock_divider_store(struct device *dev, struct device_attribute *attr,
118 const char *buf, size_t size)
119{
120 struct pti_device *pti = dev_get_drvdata(dev);
121 unsigned long val;
122 int ret;
123
124 ret = kstrtoul(s: buf, base: 10, res: &val);
125 if (ret)
126 return ret;
127
128 if (!is_power_of_2(n: val) || val > 8 || !val)
129 return -EINVAL;
130
131 pti->clkdiv = val;
132
133 return size;
134}
135
136static DEVICE_ATTR_RW(clock_divider);
137
138static struct attribute *pti_output_attrs[] = {
139 &dev_attr_mode.attr,
140 &dev_attr_freerunning_clock.attr,
141 &dev_attr_clock_divider.attr,
142 NULL,
143};
144
145static const struct attribute_group pti_output_group = {
146 .attrs = pti_output_attrs,
147};
148
149static int intel_th_pti_activate(struct intel_th_device *thdev)
150{
151 struct pti_device *pti = dev_get_drvdata(dev: &thdev->dev);
152 u32 ctl = PTI_EN;
153
154 if (pti->patgen)
155 ctl |= pti->patgen << __ffs(PTI_PATGENMODE);
156 if (pti->freeclk)
157 ctl |= PTI_FCEN;
158 ctl |= pti->mode << __ffs(PTI_MODE);
159 ctl |= pti->clkdiv << __ffs(PTI_CLKDIV);
160 ctl |= pti->lpp_dest << __ffs(LPP_DEST);
161
162 iowrite32(ctl, pti->base + REG_PTI_CTL);
163
164 intel_th_trace_enable(thdev);
165
166 return 0;
167}
168
169static void intel_th_pti_deactivate(struct intel_th_device *thdev)
170{
171 struct pti_device *pti = dev_get_drvdata(dev: &thdev->dev);
172
173 intel_th_trace_disable(thdev);
174
175 iowrite32(0, pti->base + REG_PTI_CTL);
176}
177
178static void read_hw_config(struct pti_device *pti)
179{
180 u32 ctl = ioread32(pti->base + REG_PTI_CTL);
181
182 pti->mode = (ctl & PTI_MODE) >> __ffs(PTI_MODE);
183 pti->clkdiv = (ctl & PTI_CLKDIV) >> __ffs(PTI_CLKDIV);
184 pti->freeclk = !!(ctl & PTI_FCEN);
185
186 if (!pti_mode[pti->mode])
187 pti->mode = pti_width_mode(width: 4);
188 if (!pti->clkdiv)
189 pti->clkdiv = 1;
190
191 if (pti->thdev->output.type == GTH_LPP) {
192 if (ctl & LPP_PTIPRESENT)
193 pti->lpp_dest_mask |= LPP_DEST_PTI;
194 if (ctl & LPP_BSSBPRESENT)
195 pti->lpp_dest_mask |= LPP_DEST_EXI;
196 if (ctl & LPP_DEST)
197 pti->lpp_dest = 1;
198 }
199}
200
201static int intel_th_pti_probe(struct intel_th_device *thdev)
202{
203 struct device *dev = &thdev->dev;
204 struct resource *res;
205 struct pti_device *pti;
206 void __iomem *base;
207
208 res = intel_th_device_get_resource(thdev, IORESOURCE_MEM, num: 0);
209 if (!res)
210 return -ENODEV;
211
212 base = devm_ioremap(dev, offset: res->start, size: resource_size(res));
213 if (!base)
214 return -ENOMEM;
215
216 pti = devm_kzalloc(dev, size: sizeof(*pti), GFP_KERNEL);
217 if (!pti)
218 return -ENOMEM;
219
220 pti->thdev = thdev;
221 pti->base = base;
222
223 read_hw_config(pti);
224
225 dev_set_drvdata(dev, data: pti);
226
227 return 0;
228}
229
230static void intel_th_pti_remove(struct intel_th_device *thdev)
231{
232}
233
234static struct intel_th_driver intel_th_pti_driver = {
235 .probe = intel_th_pti_probe,
236 .remove = intel_th_pti_remove,
237 .activate = intel_th_pti_activate,
238 .deactivate = intel_th_pti_deactivate,
239 .attr_group = &pti_output_group,
240 .driver = {
241 .name = "pti",
242 .owner = THIS_MODULE,
243 },
244};
245
246static const char * const lpp_dest_str[] = { "pti", "exi" };
247
248static ssize_t lpp_dest_show(struct device *dev, struct device_attribute *attr,
249 char *buf)
250{
251 struct pti_device *pti = dev_get_drvdata(dev);
252 ssize_t ret = 0;
253 int i;
254
255 for (i = ARRAY_SIZE(lpp_dest_str) - 1; i >= 0; i--) {
256 const char *fmt = pti->lpp_dest == i ? "[%s] " : "%s ";
257
258 if (!(pti->lpp_dest_mask & BIT(i)))
259 continue;
260
261 ret += scnprintf(buf: buf + ret, PAGE_SIZE - ret,
262 fmt, lpp_dest_str[i]);
263 }
264
265 if (ret)
266 buf[ret - 1] = '\n';
267
268 return ret;
269}
270
271static ssize_t lpp_dest_store(struct device *dev, struct device_attribute *attr,
272 const char *buf, size_t size)
273{
274 struct pti_device *pti = dev_get_drvdata(dev);
275 int i;
276
277 i = sysfs_match_string(lpp_dest_str, buf);
278 if (i < 0)
279 return i;
280
281 if (!(pti->lpp_dest_mask & BIT(i)))
282 return -EINVAL;
283
284 pti->lpp_dest = i;
285 return size;
286}
287
288static DEVICE_ATTR_RW(lpp_dest);
289
290static struct attribute *lpp_output_attrs[] = {
291 &dev_attr_mode.attr,
292 &dev_attr_freerunning_clock.attr,
293 &dev_attr_clock_divider.attr,
294 &dev_attr_lpp_dest.attr,
295 NULL,
296};
297
298static const struct attribute_group lpp_output_group = {
299 .attrs = lpp_output_attrs,
300};
301
302static struct intel_th_driver intel_th_lpp_driver = {
303 .probe = intel_th_pti_probe,
304 .remove = intel_th_pti_remove,
305 .activate = intel_th_pti_activate,
306 .deactivate = intel_th_pti_deactivate,
307 .attr_group = &lpp_output_group,
308 .driver = {
309 .name = "lpp",
310 .owner = THIS_MODULE,
311 },
312};
313
314static int __init intel_th_pti_lpp_init(void)
315{
316 int err;
317
318 err = intel_th_driver_register(thdrv: &intel_th_pti_driver);
319 if (err)
320 return err;
321
322 err = intel_th_driver_register(thdrv: &intel_th_lpp_driver);
323 if (err) {
324 intel_th_driver_unregister(thdrv: &intel_th_pti_driver);
325 return err;
326 }
327
328 return 0;
329}
330
331module_init(intel_th_pti_lpp_init);
332
333static void __exit intel_th_pti_lpp_exit(void)
334{
335 intel_th_driver_unregister(thdrv: &intel_th_pti_driver);
336 intel_th_driver_unregister(thdrv: &intel_th_lpp_driver);
337}
338
339module_exit(intel_th_pti_lpp_exit);
340
341MODULE_LICENSE("GPL v2");
342MODULE_DESCRIPTION("Intel(R) Trace Hub PTI/LPP output driver");
343MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");
344

source code of linux/drivers/hwtracing/intel_th/pti.c