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
22 struct 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 */
34 static const unsigned int pti_mode[] = {
35 0, 4, 8, 0, 12, 0, 0, 0, 16, 0, 0, 0, 0, 0, 0, 0,
36 };
37
pti_width_mode(unsigned int width)38 static 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
mode_show(struct device * dev,struct device_attribute * attr,char * buf)49 static 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, "%d\n", pti_mode[pti->mode]);
55 }
56
mode_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t size)57 static 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(buf, 10, &val);
65 if (ret)
66 return ret;
67
68 ret = pti_width_mode(val);
69 if (ret < 0)
70 return ret;
71
72 pti->mode = ret;
73
74 return size;
75 }
76
77 static DEVICE_ATTR_RW(mode);
78
79 static ssize_t
freerunning_clock_show(struct device * dev,struct device_attribute * attr,char * buf)80 freerunning_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, "%d\n", pti->freeclk);
86 }
87
88 static ssize_t
freerunning_clock_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t size)89 freerunning_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(buf, 10, &val);
97 if (ret)
98 return ret;
99
100 pti->freeclk = !!val;
101
102 return size;
103 }
104
105 static DEVICE_ATTR_RW(freerunning_clock);
106
107 static ssize_t
clock_divider_show(struct device * dev,struct device_attribute * attr,char * buf)108 clock_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, "%d\n", 1u << pti->clkdiv);
114 }
115
116 static ssize_t
clock_divider_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t size)117 clock_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(buf, 10, &val);
125 if (ret)
126 return ret;
127
128 if (!is_power_of_2(val) || val > 8 || !val)
129 return -EINVAL;
130
131 pti->clkdiv = val;
132
133 return size;
134 }
135
136 static DEVICE_ATTR_RW(clock_divider);
137
138 static 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
145 static const struct attribute_group pti_output_group = {
146 .attrs = pti_output_attrs,
147 };
148
intel_th_pti_activate(struct intel_th_device * thdev)149 static int intel_th_pti_activate(struct intel_th_device *thdev)
150 {
151 struct pti_device *pti = dev_get_drvdata(&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
intel_th_pti_deactivate(struct intel_th_device * thdev)169 static void intel_th_pti_deactivate(struct intel_th_device *thdev)
170 {
171 struct pti_device *pti = dev_get_drvdata(&thdev->dev);
172
173 intel_th_trace_disable(thdev);
174
175 iowrite32(0, pti->base + REG_PTI_CTL);
176 }
177
read_hw_config(struct pti_device * pti)178 static 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(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
intel_th_pti_probe(struct intel_th_device * thdev)201 static 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, 0);
209 if (!res)
210 return -ENODEV;
211
212 base = devm_ioremap(dev, res->start, resource_size(res));
213 if (!base)
214 return -ENOMEM;
215
216 pti = devm_kzalloc(dev, 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, pti);
226
227 return 0;
228 }
229
intel_th_pti_remove(struct intel_th_device * thdev)230 static void intel_th_pti_remove(struct intel_th_device *thdev)
231 {
232 }
233
234 static 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
246 static const char * const lpp_dest_str[] = { "pti", "exi" };
247
lpp_dest_show(struct device * dev,struct device_attribute * attr,char * buf)248 static 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 + 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
lpp_dest_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t size)271 static 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
288 static DEVICE_ATTR_RW(lpp_dest);
289
290 static 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
298 static const struct attribute_group lpp_output_group = {
299 .attrs = lpp_output_attrs,
300 };
301
302 static 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
intel_th_pti_lpp_init(void)314 static int __init intel_th_pti_lpp_init(void)
315 {
316 int err;
317
318 err = intel_th_driver_register(&intel_th_pti_driver);
319 if (err)
320 return err;
321
322 err = intel_th_driver_register(&intel_th_lpp_driver);
323 if (err) {
324 intel_th_driver_unregister(&intel_th_pti_driver);
325 return err;
326 }
327
328 return 0;
329 }
330
331 module_init(intel_th_pti_lpp_init);
332
intel_th_pti_lpp_exit(void)333 static void __exit intel_th_pti_lpp_exit(void)
334 {
335 intel_th_driver_unregister(&intel_th_pti_driver);
336 intel_th_driver_unregister(&intel_th_lpp_driver);
337 }
338
339 module_exit(intel_th_pti_lpp_exit);
340
341 MODULE_LICENSE("GPL v2");
342 MODULE_DESCRIPTION("Intel(R) Trace Hub PTI/LPP output driver");
343 MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");
344