xref: /linux/drivers/platform/x86/intel/plr_tpmi.c (revision 9669b2499ea377764f8320dd562dd6cd4ea80a5d)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Performance Limit Reasons via TPMI
4  *
5  * Copyright (c) 2024, Intel Corporation.
6  */
7 
8 #include <linux/array_size.h>
9 #include <linux/auxiliary_bus.h>
10 #include <linux/bitfield.h>
11 #include <linux/bitmap.h>
12 #include <linux/debugfs.h>
13 #include <linux/device.h>
14 #include <linux/err.h>
15 #include <linux/gfp_types.h>
16 #include <linux/intel_tpmi.h>
17 #include <linux/intel_vsec.h>
18 #include <linux/io.h>
19 #include <linux/iopoll.h>
20 #include <linux/kstrtox.h>
21 #include <linux/lockdep.h>
22 #include <linux/module.h>
23 #include <linux/mod_devicetable.h>
24 #include <linux/mutex.h>
25 #include <linux/seq_file.h>
26 #include <linux/sprintf.h>
27 #include <linux/types.h>
28 
29 #include "tpmi_power_domains.h"
30 
31 #define PLR_HEADER		0x00
32 #define PLR_MAILBOX_INTERFACE	0x08
33 #define PLR_MAILBOX_DATA	0x10
34 #define PLR_DIE_LEVEL		0x18
35 
36 #define PLR_MODULE_ID_MASK	GENMASK_ULL(19, 12)
37 #define PLR_RUN_BUSY		BIT_ULL(63)
38 
39 #define PLR_COMMAND_WRITE	1
40 
41 #define PLR_INVALID		GENMASK_ULL(63, 0)
42 
43 #define PLR_TIMEOUT_US		5
44 #define PLR_TIMEOUT_MAX_US	1000
45 
46 #define PLR_COARSE_REASON_BITS	32
47 
48 struct tpmi_plr;
49 
50 struct tpmi_plr_die {
51 	void __iomem *base;
52 	struct mutex lock; /* Protect access to PLR mailbox */
53 	int package_id;
54 	int die_id;
55 	struct tpmi_plr *plr;
56 };
57 
58 struct tpmi_plr {
59 	struct dentry *dbgfs_dir;
60 	struct tpmi_plr_die *die_info;
61 	int num_dies;
62 	struct auxiliary_device *auxdev;
63 };
64 
65 static const char * const plr_coarse_reasons[] = {
66 	"FREQUENCY",
67 	"CURRENT",
68 	"POWER",
69 	"THERMAL",
70 	"PLATFORM",
71 	"MCP",
72 	"RAS",
73 	"MISC",
74 	"QOS",
75 	"DFC",
76 };
77 
78 static const char * const plr_fine_reasons[] = {
79 	"FREQUENCY_CDYN0",
80 	"FREQUENCY_CDYN1",
81 	"FREQUENCY_CDYN2",
82 	"FREQUENCY_CDYN3",
83 	"FREQUENCY_CDYN4",
84 	"FREQUENCY_CDYN5",
85 	"FREQUENCY_FCT",
86 	"FREQUENCY_PCS_TRL",
87 	"CURRENT_MTPMAX",
88 	"POWER_FAST_RAPL",
89 	"POWER_PKG_PL1_MSR_TPMI",
90 	"POWER_PKG_PL1_MMIO",
91 	"POWER_PKG_PL1_PCS",
92 	"POWER_PKG_PL2_MSR_TPMI",
93 	"POWER_PKG_PL2_MMIO",
94 	"POWER_PKG_PL2_PCS",
95 	"POWER_PLATFORM_PL1_MSR_TPMI",
96 	"POWER_PLATFORM_PL1_MMIO",
97 	"POWER_PLATFORM_PL1_PCS",
98 	"POWER_PLATFORM_PL2_MSR_TPMI",
99 	"POWER_PLATFORM_PL2_MMIO",
100 	"POWER_PLATFORM_PL2_PCS",
101 	"UNKNOWN(22)",
102 	"THERMAL_PER_CORE",
103 	"DFC_UFS",
104 	"PLATFORM_PROCHOT",
105 	"PLATFORM_HOT_VR",
106 	"UNKNOWN(27)",
107 	"UNKNOWN(28)",
108 	"MISC_PCS_PSTATE",
109 };
110 
plr_read(struct tpmi_plr_die * plr_die,int offset)111 static u64 plr_read(struct tpmi_plr_die *plr_die, int offset)
112 {
113 	return readq(plr_die->base + offset);
114 }
115 
plr_write(u64 val,struct tpmi_plr_die * plr_die,int offset)116 static void plr_write(u64 val, struct tpmi_plr_die *plr_die, int offset)
117 {
118 	writeq(val, plr_die->base + offset);
119 }
120 
plr_read_cpu_status(struct tpmi_plr_die * plr_die,int cpu,u64 * status)121 static int plr_read_cpu_status(struct tpmi_plr_die *plr_die, int cpu,
122 			       u64 *status)
123 {
124 	u64 regval;
125 	int ret;
126 
127 	lockdep_assert_held(&plr_die->lock);
128 
129 	regval = FIELD_PREP(PLR_MODULE_ID_MASK, tpmi_get_punit_core_number(cpu));
130 	regval |= PLR_RUN_BUSY;
131 
132 	plr_write(regval, plr_die, PLR_MAILBOX_INTERFACE);
133 
134 	ret = readq_poll_timeout(plr_die->base + PLR_MAILBOX_INTERFACE, regval,
135 				 !(regval & PLR_RUN_BUSY), PLR_TIMEOUT_US,
136 				 PLR_TIMEOUT_MAX_US);
137 	if (ret)
138 		return ret;
139 
140 	*status = plr_read(plr_die, PLR_MAILBOX_DATA);
141 
142 	return 0;
143 }
144 
plr_clear_cpu_status(struct tpmi_plr_die * plr_die,int cpu)145 static int plr_clear_cpu_status(struct tpmi_plr_die *plr_die, int cpu)
146 {
147 	u64 regval;
148 
149 	lockdep_assert_held(&plr_die->lock);
150 
151 	regval = FIELD_PREP(PLR_MODULE_ID_MASK, tpmi_get_punit_core_number(cpu));
152 	regval |= PLR_RUN_BUSY | PLR_COMMAND_WRITE;
153 
154 	plr_write(0, plr_die, PLR_MAILBOX_DATA);
155 
156 	plr_write(regval, plr_die, PLR_MAILBOX_INTERFACE);
157 
158 	return readq_poll_timeout(plr_die->base + PLR_MAILBOX_INTERFACE, regval,
159 				  !(regval & PLR_RUN_BUSY), PLR_TIMEOUT_US,
160 				  PLR_TIMEOUT_MAX_US);
161 }
162 
plr_print_bits(struct seq_file * s,u64 val,int bits)163 static void plr_print_bits(struct seq_file *s, u64 val, int bits)
164 {
165 	const unsigned long mask[] = { BITMAP_FROM_U64(val) };
166 	int bit, index;
167 
168 	for_each_set_bit(bit, mask, bits) {
169 		const char *str = NULL;
170 
171 		if (bit < PLR_COARSE_REASON_BITS) {
172 			if (bit < ARRAY_SIZE(plr_coarse_reasons))
173 				str = plr_coarse_reasons[bit];
174 		} else {
175 			index = bit - PLR_COARSE_REASON_BITS;
176 			if (index < ARRAY_SIZE(plr_fine_reasons))
177 				str = plr_fine_reasons[index];
178 		}
179 
180 		if (str)
181 			seq_printf(s, " %s", str);
182 		else
183 			seq_printf(s, " UNKNOWN(%d)", bit);
184 	}
185 
186 	if (!val)
187 		seq_puts(s, " none");
188 
189 	seq_putc(s, '\n');
190 }
191 
plr_status_show(struct seq_file * s,void * unused)192 static int plr_status_show(struct seq_file *s, void *unused)
193 {
194 	struct tpmi_plr_die *plr_die = s->private;
195 	int ret;
196 	u64 val;
197 
198 	val = plr_read(plr_die, PLR_DIE_LEVEL);
199 	seq_puts(s, "cpus");
200 	plr_print_bits(s, val, 32);
201 
202 	guard(mutex)(&plr_die->lock);
203 
204 	for (int cpu = 0; cpu < nr_cpu_ids; cpu++) {
205 		if (plr_die->die_id != tpmi_get_power_domain_id(cpu))
206 			continue;
207 
208 		if (plr_die->package_id != topology_physical_package_id(cpu))
209 			continue;
210 
211 		seq_printf(s, "cpu%d", cpu);
212 		ret = plr_read_cpu_status(plr_die, cpu, &val);
213 		if (ret) {
214 			dev_err(&plr_die->plr->auxdev->dev, "Failed to read PLR for cpu %d, ret=%d\n",
215 				cpu, ret);
216 			return ret;
217 		}
218 
219 		plr_print_bits(s, val, 64);
220 	}
221 
222 	return 0;
223 }
224 
plr_status_write(struct file * filp,const char __user * ubuf,size_t count,loff_t * ppos)225 static ssize_t plr_status_write(struct file *filp, const char __user *ubuf,
226 				size_t count, loff_t *ppos)
227 {
228 	struct seq_file *s = filp->private_data;
229 	struct tpmi_plr_die *plr_die = s->private;
230 	bool val;
231 	int ret;
232 
233 	ret = kstrtobool_from_user(ubuf, count, &val);
234 	if (ret)
235 		return ret;
236 
237 	if (val != 0)
238 		return -EINVAL;
239 
240 	plr_write(0, plr_die, PLR_DIE_LEVEL);
241 
242 	guard(mutex)(&plr_die->lock);
243 
244 	for (int cpu = 0; cpu < nr_cpu_ids; cpu++) {
245 		if (plr_die->die_id != tpmi_get_power_domain_id(cpu))
246 			continue;
247 
248 		if (plr_die->package_id != topology_physical_package_id(cpu))
249 			continue;
250 
251 		plr_clear_cpu_status(plr_die, cpu);
252 	}
253 
254 	return count;
255 }
256 DEFINE_SHOW_STORE_ATTRIBUTE(plr_status);
257 
intel_plr_probe(struct auxiliary_device * auxdev,const struct auxiliary_device_id * id)258 static int intel_plr_probe(struct auxiliary_device *auxdev, const struct auxiliary_device_id *id)
259 {
260 	struct oobmsm_plat_info *plat_info;
261 	struct dentry *dentry;
262 	int i, num_resources;
263 	struct resource *res;
264 	struct tpmi_plr *plr;
265 	void __iomem *base;
266 	char name[17];
267 	int err;
268 
269 	plat_info = tpmi_get_platform_data(auxdev);
270 	if (!plat_info)
271 		return dev_err_probe(&auxdev->dev, -EINVAL, "No platform info\n");
272 
273 	dentry = tpmi_get_debugfs_dir(auxdev);
274 	if (!dentry)
275 		return dev_err_probe(&auxdev->dev, -ENODEV, "No TPMI debugfs directory.\n");
276 
277 	num_resources = tpmi_get_resource_count(auxdev);
278 	if (!num_resources)
279 		return -EINVAL;
280 
281 	plr = devm_kzalloc(&auxdev->dev, sizeof(*plr), GFP_KERNEL);
282 	if (!plr)
283 		return -ENOMEM;
284 
285 	plr->die_info = devm_kcalloc(&auxdev->dev, num_resources, sizeof(*plr->die_info),
286 				     GFP_KERNEL);
287 	if (!plr->die_info)
288 		return -ENOMEM;
289 
290 	plr->num_dies = num_resources;
291 	plr->dbgfs_dir = debugfs_create_dir("plr", dentry);
292 	plr->auxdev = auxdev;
293 
294 	for (i = 0; i < num_resources; i++) {
295 		res = tpmi_get_resource_at_index(auxdev, i);
296 		if (!res) {
297 			err = dev_err_probe(&auxdev->dev, -EINVAL, "No resource\n");
298 			goto err;
299 		}
300 
301 		base = devm_ioremap_resource(&auxdev->dev, res);
302 		if (IS_ERR(base)) {
303 			err = PTR_ERR(base);
304 			goto err;
305 		}
306 
307 		plr->die_info[i].base = base;
308 		plr->die_info[i].package_id = plat_info->package_id;
309 		plr->die_info[i].die_id = i;
310 		plr->die_info[i].plr = plr;
311 		mutex_init(&plr->die_info[i].lock);
312 
313 		if (plr_read(&plr->die_info[i], PLR_HEADER) == PLR_INVALID)
314 			continue;
315 
316 		snprintf(name, sizeof(name), "domain%d", i);
317 
318 		dentry = debugfs_create_dir(name, plr->dbgfs_dir);
319 		debugfs_create_file("status", 0444, dentry, &plr->die_info[i],
320 				    &plr_status_fops);
321 	}
322 
323 	auxiliary_set_drvdata(auxdev, plr);
324 
325 	return 0;
326 
327 err:
328 	debugfs_remove_recursive(plr->dbgfs_dir);
329 	return err;
330 }
331 
intel_plr_remove(struct auxiliary_device * auxdev)332 static void intel_plr_remove(struct auxiliary_device *auxdev)
333 {
334 	struct tpmi_plr *plr = auxiliary_get_drvdata(auxdev);
335 
336 	debugfs_remove_recursive(plr->dbgfs_dir);
337 }
338 
339 static const struct auxiliary_device_id intel_plr_id_table[] = {
340 	{ .name = "intel_vsec.tpmi-plr" },
341 	{}
342 };
343 MODULE_DEVICE_TABLE(auxiliary, intel_plr_id_table);
344 
345 static struct auxiliary_driver intel_plr_aux_driver = {
346 	.id_table       = intel_plr_id_table,
347 	.remove         = intel_plr_remove,
348 	.probe          = intel_plr_probe,
349 };
350 module_auxiliary_driver(intel_plr_aux_driver);
351 
352 MODULE_IMPORT_NS("INTEL_TPMI");
353 MODULE_IMPORT_NS("INTEL_TPMI_POWER_DOMAIN");
354 MODULE_DESCRIPTION("Intel TPMI PLR Driver");
355 MODULE_LICENSE("GPL");
356