1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * AMD SoC Power Management Controller Driver
4  *
5  * Copyright (c) 2020, Advanced Micro Devices, Inc.
6  * All Rights Reserved.
7  *
8  * Author: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
9  */
10 
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12 
13 #include <linux/acpi.h>
14 #include <linux/bitfield.h>
15 #include <linux/bits.h>
16 #include <linux/debugfs.h>
17 #include <linux/delay.h>
18 #include <linux/io.h>
19 #include <linux/iopoll.h>
20 #include <linux/module.h>
21 #include <linux/pci.h>
22 #include <linux/platform_device.h>
23 #include <linux/suspend.h>
24 #include <linux/seq_file.h>
25 #include <linux/uaccess.h>
26 
27 /* SMU communication registers */
28 #define AMD_PMC_REGISTER_MESSAGE	0x538
29 #define AMD_PMC_REGISTER_RESPONSE	0x980
30 #define AMD_PMC_REGISTER_ARGUMENT	0x9BC
31 
32 /* Base address of SMU for mapping physical address to virtual address */
33 #define AMD_PMC_SMU_INDEX_ADDRESS	0xB8
34 #define AMD_PMC_SMU_INDEX_DATA		0xBC
35 #define AMD_PMC_MAPPING_SIZE		0x01000
36 #define AMD_PMC_BASE_ADDR_OFFSET	0x10000
37 #define AMD_PMC_BASE_ADDR_LO		0x13B102E8
38 #define AMD_PMC_BASE_ADDR_HI		0x13B102EC
39 #define AMD_PMC_BASE_ADDR_LO_MASK	GENMASK(15, 0)
40 #define AMD_PMC_BASE_ADDR_HI_MASK	GENMASK(31, 20)
41 
42 /* SMU Response Codes */
43 #define AMD_PMC_RESULT_OK                    0x01
44 #define AMD_PMC_RESULT_CMD_REJECT_BUSY       0xFC
45 #define AMD_PMC_RESULT_CMD_REJECT_PREREQ     0xFD
46 #define AMD_PMC_RESULT_CMD_UNKNOWN           0xFE
47 #define AMD_PMC_RESULT_FAILED                0xFF
48 
49 /* FCH SSC Registers */
50 #define FCH_S0I3_ENTRY_TIME_L_OFFSET	0x30
51 #define FCH_S0I3_ENTRY_TIME_H_OFFSET	0x34
52 #define FCH_S0I3_EXIT_TIME_L_OFFSET	0x38
53 #define FCH_S0I3_EXIT_TIME_H_OFFSET	0x3C
54 #define FCH_SSC_MAPPING_SIZE		0x800
55 #define FCH_BASE_PHY_ADDR_LOW		0xFED81100
56 #define FCH_BASE_PHY_ADDR_HIGH		0x00000000
57 
58 /* SMU Message Definations */
59 #define SMU_MSG_GETSMUVERSION		0x02
60 #define SMU_MSG_LOG_GETDRAM_ADDR_HI	0x04
61 #define SMU_MSG_LOG_GETDRAM_ADDR_LO	0x05
62 #define SMU_MSG_LOG_START		0x06
63 #define SMU_MSG_LOG_RESET		0x07
64 #define SMU_MSG_LOG_DUMP_DATA		0x08
65 #define SMU_MSG_GET_SUP_CONSTRAINTS	0x09
66 /* List of supported CPU ids */
67 #define AMD_CPU_ID_RV			0x15D0
68 #define AMD_CPU_ID_RN			0x1630
69 #define AMD_CPU_ID_PCO			AMD_CPU_ID_RV
70 #define AMD_CPU_ID_CZN			AMD_CPU_ID_RN
71 #define AMD_CPU_ID_YC			0x14B5
72 
73 #define PMC_MSG_DELAY_MIN_US		100
74 #define RESPONSE_REGISTER_LOOP_MAX	20000
75 
76 #define SOC_SUBSYSTEM_IP_MAX	12
77 #define DELAY_MIN_US		2000
78 #define DELAY_MAX_US		3000
79 enum amd_pmc_def {
80 	MSG_TEST = 0x01,
81 	MSG_OS_HINT_PCO,
82 	MSG_OS_HINT_RN,
83 };
84 
85 struct amd_pmc_bit_map {
86 	const char *name;
87 	u32 bit_mask;
88 };
89 
90 static const struct amd_pmc_bit_map soc15_ip_blk[] = {
91 	{"DISPLAY",	BIT(0)},
92 	{"CPU",		BIT(1)},
93 	{"GFX",		BIT(2)},
94 	{"VDD",		BIT(3)},
95 	{"ACP",		BIT(4)},
96 	{"VCN",		BIT(5)},
97 	{"ISP",		BIT(6)},
98 	{"NBIO",	BIT(7)},
99 	{"DF",		BIT(8)},
100 	{"USB0",	BIT(9)},
101 	{"USB1",	BIT(10)},
102 	{"LAPIC",	BIT(11)},
103 	{}
104 };
105 
106 struct amd_pmc_dev {
107 	void __iomem *regbase;
108 	void __iomem *smu_virt_addr;
109 	void __iomem *fch_virt_addr;
110 	u32 base_addr;
111 	u32 cpu_id;
112 	u32 active_ips;
113 	struct device *dev;
114 	struct mutex lock; /* generic mutex lock */
115 #if IS_ENABLED(CONFIG_DEBUG_FS)
116 	struct dentry *dbgfs_dir;
117 #endif /* CONFIG_DEBUG_FS */
118 };
119 
120 static struct amd_pmc_dev pmc;
121 static int amd_pmc_send_cmd(struct amd_pmc_dev *dev, bool set, u32 *data, u8 msg, bool ret);
122 
amd_pmc_reg_read(struct amd_pmc_dev * dev,int reg_offset)123 static inline u32 amd_pmc_reg_read(struct amd_pmc_dev *dev, int reg_offset)
124 {
125 	return ioread32(dev->regbase + reg_offset);
126 }
127 
amd_pmc_reg_write(struct amd_pmc_dev * dev,int reg_offset,u32 val)128 static inline void amd_pmc_reg_write(struct amd_pmc_dev *dev, int reg_offset, u32 val)
129 {
130 	iowrite32(val, dev->regbase + reg_offset);
131 }
132 
133 struct smu_metrics {
134 	u32 table_version;
135 	u32 hint_count;
136 	u32 s0i3_cyclecount;
137 	u32 timein_s0i2;
138 	u64 timeentering_s0i3_lastcapture;
139 	u64 timeentering_s0i3_totaltime;
140 	u64 timeto_resume_to_os_lastcapture;
141 	u64 timeto_resume_to_os_totaltime;
142 	u64 timein_s0i3_lastcapture;
143 	u64 timein_s0i3_totaltime;
144 	u64 timein_swdrips_lastcapture;
145 	u64 timein_swdrips_totaltime;
146 	u64 timecondition_notmet_lastcapture[SOC_SUBSYSTEM_IP_MAX];
147 	u64 timecondition_notmet_totaltime[SOC_SUBSYSTEM_IP_MAX];
148 } __packed;
149 
150 #ifdef CONFIG_DEBUG_FS
smu_fw_info_show(struct seq_file * s,void * unused)151 static int smu_fw_info_show(struct seq_file *s, void *unused)
152 {
153 	struct amd_pmc_dev *dev = s->private;
154 	struct smu_metrics table;
155 	int idx;
156 
157 	if (dev->cpu_id == AMD_CPU_ID_PCO)
158 		return -EINVAL;
159 
160 	memcpy_fromio(&table, dev->smu_virt_addr, sizeof(struct smu_metrics));
161 
162 	seq_puts(s, "\n=== SMU Statistics ===\n");
163 	seq_printf(s, "Table Version: %d\n", table.table_version);
164 	seq_printf(s, "Hint Count: %d\n", table.hint_count);
165 	seq_printf(s, "S0i3 Cycle Count: %d\n", table.s0i3_cyclecount);
166 	seq_printf(s, "Time (in us) to S0i3: %lld\n", table.timeentering_s0i3_lastcapture);
167 	seq_printf(s, "Time (in us) in S0i3: %lld\n", table.timein_s0i3_lastcapture);
168 
169 	seq_puts(s, "\n=== Active time (in us) ===\n");
170 	for (idx = 0 ; idx < SOC_SUBSYSTEM_IP_MAX ; idx++) {
171 		if (soc15_ip_blk[idx].bit_mask & dev->active_ips)
172 			seq_printf(s, "%-8s : %lld\n", soc15_ip_blk[idx].name,
173 				   table.timecondition_notmet_lastcapture[idx]);
174 	}
175 
176 	return 0;
177 }
178 DEFINE_SHOW_ATTRIBUTE(smu_fw_info);
179 
s0ix_stats_show(struct seq_file * s,void * unused)180 static int s0ix_stats_show(struct seq_file *s, void *unused)
181 {
182 	struct amd_pmc_dev *dev = s->private;
183 	u64 entry_time, exit_time, residency;
184 
185 	entry_time = ioread32(dev->fch_virt_addr + FCH_S0I3_ENTRY_TIME_H_OFFSET);
186 	entry_time = entry_time << 32 | ioread32(dev->fch_virt_addr + FCH_S0I3_ENTRY_TIME_L_OFFSET);
187 
188 	exit_time = ioread32(dev->fch_virt_addr + FCH_S0I3_EXIT_TIME_H_OFFSET);
189 	exit_time = exit_time << 32 | ioread32(dev->fch_virt_addr + FCH_S0I3_EXIT_TIME_L_OFFSET);
190 
191 	/* It's in 48MHz. We need to convert it */
192 	residency = exit_time - entry_time;
193 	do_div(residency, 48);
194 
195 	seq_puts(s, "=== S0ix statistics ===\n");
196 	seq_printf(s, "S0ix Entry Time: %lld\n", entry_time);
197 	seq_printf(s, "S0ix Exit Time: %lld\n", exit_time);
198 	seq_printf(s, "Residency Time: %lld\n", residency);
199 
200 	return 0;
201 }
202 DEFINE_SHOW_ATTRIBUTE(s0ix_stats);
203 
amd_pmc_dbgfs_unregister(struct amd_pmc_dev * dev)204 static void amd_pmc_dbgfs_unregister(struct amd_pmc_dev *dev)
205 {
206 	debugfs_remove_recursive(dev->dbgfs_dir);
207 }
208 
amd_pmc_dbgfs_register(struct amd_pmc_dev * dev)209 static void amd_pmc_dbgfs_register(struct amd_pmc_dev *dev)
210 {
211 	dev->dbgfs_dir = debugfs_create_dir("amd_pmc", NULL);
212 	debugfs_create_file("smu_fw_info", 0644, dev->dbgfs_dir, dev,
213 			    &smu_fw_info_fops);
214 	debugfs_create_file("s0ix_stats", 0644, dev->dbgfs_dir, dev,
215 			    &s0ix_stats_fops);
216 }
217 #else
amd_pmc_dbgfs_register(struct amd_pmc_dev * dev)218 static inline void amd_pmc_dbgfs_register(struct amd_pmc_dev *dev)
219 {
220 }
221 
amd_pmc_dbgfs_unregister(struct amd_pmc_dev * dev)222 static inline void amd_pmc_dbgfs_unregister(struct amd_pmc_dev *dev)
223 {
224 }
225 #endif /* CONFIG_DEBUG_FS */
226 
amd_pmc_setup_smu_logging(struct amd_pmc_dev * dev)227 static int amd_pmc_setup_smu_logging(struct amd_pmc_dev *dev)
228 {
229 	u32 phys_addr_low, phys_addr_hi;
230 	u64 smu_phys_addr;
231 
232 	if (dev->cpu_id == AMD_CPU_ID_PCO)
233 		return -EINVAL;
234 
235 	/* Get Active devices list from SMU */
236 	amd_pmc_send_cmd(dev, 0, &dev->active_ips, SMU_MSG_GET_SUP_CONSTRAINTS, 1);
237 
238 	/* Get dram address */
239 	amd_pmc_send_cmd(dev, 0, &phys_addr_low, SMU_MSG_LOG_GETDRAM_ADDR_LO, 1);
240 	amd_pmc_send_cmd(dev, 0, &phys_addr_hi, SMU_MSG_LOG_GETDRAM_ADDR_HI, 1);
241 	smu_phys_addr = ((u64)phys_addr_hi << 32 | phys_addr_low);
242 
243 	dev->smu_virt_addr = devm_ioremap(dev->dev, smu_phys_addr, sizeof(struct smu_metrics));
244 	if (!dev->smu_virt_addr)
245 		return -ENOMEM;
246 
247 	/* Start the logging */
248 	amd_pmc_send_cmd(dev, 0, NULL, SMU_MSG_LOG_START, 0);
249 
250 	return 0;
251 }
252 
amd_pmc_dump_registers(struct amd_pmc_dev * dev)253 static void amd_pmc_dump_registers(struct amd_pmc_dev *dev)
254 {
255 	u32 value;
256 
257 	value = amd_pmc_reg_read(dev, AMD_PMC_REGISTER_RESPONSE);
258 	dev_dbg(dev->dev, "AMD_PMC_REGISTER_RESPONSE:%x\n", value);
259 
260 	value = amd_pmc_reg_read(dev, AMD_PMC_REGISTER_ARGUMENT);
261 	dev_dbg(dev->dev, "AMD_PMC_REGISTER_ARGUMENT:%x\n", value);
262 
263 	value = amd_pmc_reg_read(dev, AMD_PMC_REGISTER_MESSAGE);
264 	dev_dbg(dev->dev, "AMD_PMC_REGISTER_MESSAGE:%x\n", value);
265 }
266 
amd_pmc_send_cmd(struct amd_pmc_dev * dev,bool set,u32 * data,u8 msg,bool ret)267 static int amd_pmc_send_cmd(struct amd_pmc_dev *dev, bool set, u32 *data, u8 msg, bool ret)
268 {
269 	int rc;
270 	u32 val;
271 
272 	mutex_lock(&dev->lock);
273 	/* Wait until we get a valid response */
274 	rc = readx_poll_timeout(ioread32, dev->regbase + AMD_PMC_REGISTER_RESPONSE,
275 				val, val != 0, PMC_MSG_DELAY_MIN_US,
276 				PMC_MSG_DELAY_MIN_US * RESPONSE_REGISTER_LOOP_MAX);
277 	if (rc) {
278 		dev_err(dev->dev, "failed to talk to SMU\n");
279 		goto out_unlock;
280 	}
281 
282 	/* Write zero to response register */
283 	amd_pmc_reg_write(dev, AMD_PMC_REGISTER_RESPONSE, 0);
284 
285 	/* Write argument into response register */
286 	amd_pmc_reg_write(dev, AMD_PMC_REGISTER_ARGUMENT, set);
287 
288 	/* Write message ID to message ID register */
289 	amd_pmc_reg_write(dev, AMD_PMC_REGISTER_MESSAGE, msg);
290 
291 	/* Wait until we get a valid response */
292 	rc = readx_poll_timeout(ioread32, dev->regbase + AMD_PMC_REGISTER_RESPONSE,
293 				val, val != 0, PMC_MSG_DELAY_MIN_US,
294 				PMC_MSG_DELAY_MIN_US * RESPONSE_REGISTER_LOOP_MAX);
295 	if (rc) {
296 		dev_err(dev->dev, "SMU response timed out\n");
297 		goto out_unlock;
298 	}
299 
300 	switch (val) {
301 	case AMD_PMC_RESULT_OK:
302 		if (ret) {
303 			/* PMFW may take longer time to return back the data */
304 			usleep_range(DELAY_MIN_US, 10 * DELAY_MAX_US);
305 			*data = amd_pmc_reg_read(dev, AMD_PMC_REGISTER_ARGUMENT);
306 		}
307 		break;
308 	case AMD_PMC_RESULT_CMD_REJECT_BUSY:
309 		dev_err(dev->dev, "SMU not ready. err: 0x%x\n", val);
310 		rc = -EBUSY;
311 		goto out_unlock;
312 	case AMD_PMC_RESULT_CMD_UNKNOWN:
313 		dev_err(dev->dev, "SMU cmd unknown. err: 0x%x\n", val);
314 		rc = -EINVAL;
315 		goto out_unlock;
316 	case AMD_PMC_RESULT_CMD_REJECT_PREREQ:
317 	case AMD_PMC_RESULT_FAILED:
318 	default:
319 		dev_err(dev->dev, "SMU cmd failed. err: 0x%x\n", val);
320 		rc = -EIO;
321 		goto out_unlock;
322 	}
323 
324 out_unlock:
325 	mutex_unlock(&dev->lock);
326 	amd_pmc_dump_registers(dev);
327 	return rc;
328 }
329 
amd_pmc_get_os_hint(struct amd_pmc_dev * dev)330 static int amd_pmc_get_os_hint(struct amd_pmc_dev *dev)
331 {
332 	switch (dev->cpu_id) {
333 	case AMD_CPU_ID_PCO:
334 		return MSG_OS_HINT_PCO;
335 	case AMD_CPU_ID_RN:
336 	case AMD_CPU_ID_YC:
337 		return MSG_OS_HINT_RN;
338 	}
339 	return -EINVAL;
340 }
341 
amd_pmc_suspend(struct device * dev)342 static int __maybe_unused amd_pmc_suspend(struct device *dev)
343 {
344 	struct amd_pmc_dev *pdev = dev_get_drvdata(dev);
345 	int rc;
346 	u8 msg;
347 
348 	/* Reset and Start SMU logging - to monitor the s0i3 stats */
349 	amd_pmc_send_cmd(pdev, 0, NULL, SMU_MSG_LOG_RESET, 0);
350 	amd_pmc_send_cmd(pdev, 0, NULL, SMU_MSG_LOG_START, 0);
351 
352 	msg = amd_pmc_get_os_hint(pdev);
353 	rc = amd_pmc_send_cmd(pdev, 1, NULL, msg, 0);
354 	if (rc)
355 		dev_err(pdev->dev, "suspend failed\n");
356 
357 	return rc;
358 }
359 
amd_pmc_resume(struct device * dev)360 static int __maybe_unused amd_pmc_resume(struct device *dev)
361 {
362 	struct amd_pmc_dev *pdev = dev_get_drvdata(dev);
363 	int rc;
364 	u8 msg;
365 
366 	/* Let SMU know that we are looking for stats */
367 	amd_pmc_send_cmd(pdev, 0, NULL, SMU_MSG_LOG_DUMP_DATA, 0);
368 
369 	msg = amd_pmc_get_os_hint(pdev);
370 	rc = amd_pmc_send_cmd(pdev, 0, NULL, msg, 0);
371 	if (rc)
372 		dev_err(pdev->dev, "resume failed\n");
373 
374 	return 0;
375 }
376 
377 static const struct dev_pm_ops amd_pmc_pm_ops = {
378 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(amd_pmc_suspend, amd_pmc_resume)
379 };
380 
381 static const struct pci_device_id pmc_pci_ids[] = {
382 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, AMD_CPU_ID_YC) },
383 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, AMD_CPU_ID_CZN) },
384 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, AMD_CPU_ID_RN) },
385 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, AMD_CPU_ID_PCO) },
386 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, AMD_CPU_ID_RV) },
387 	{ }
388 };
389 
amd_pmc_probe(struct platform_device * pdev)390 static int amd_pmc_probe(struct platform_device *pdev)
391 {
392 	struct amd_pmc_dev *dev = &pmc;
393 	struct pci_dev *rdev;
394 	u32 base_addr_lo, base_addr_hi;
395 	u64 base_addr, fch_phys_addr;
396 	int err;
397 	u32 val;
398 
399 	dev->dev = &pdev->dev;
400 
401 	rdev = pci_get_domain_bus_and_slot(0, 0, PCI_DEVFN(0, 0));
402 	if (!rdev || !pci_match_id(pmc_pci_ids, rdev)) {
403 		pci_dev_put(rdev);
404 		return -ENODEV;
405 	}
406 
407 	dev->cpu_id = rdev->device;
408 	err = pci_write_config_dword(rdev, AMD_PMC_SMU_INDEX_ADDRESS, AMD_PMC_BASE_ADDR_LO);
409 	if (err) {
410 		dev_err(dev->dev, "error writing to 0x%x\n", AMD_PMC_SMU_INDEX_ADDRESS);
411 		pci_dev_put(rdev);
412 		return pcibios_err_to_errno(err);
413 	}
414 
415 	err = pci_read_config_dword(rdev, AMD_PMC_SMU_INDEX_DATA, &val);
416 	if (err) {
417 		pci_dev_put(rdev);
418 		return pcibios_err_to_errno(err);
419 	}
420 
421 	base_addr_lo = val & AMD_PMC_BASE_ADDR_HI_MASK;
422 
423 	err = pci_write_config_dword(rdev, AMD_PMC_SMU_INDEX_ADDRESS, AMD_PMC_BASE_ADDR_HI);
424 	if (err) {
425 		dev_err(dev->dev, "error writing to 0x%x\n", AMD_PMC_SMU_INDEX_ADDRESS);
426 		pci_dev_put(rdev);
427 		return pcibios_err_to_errno(err);
428 	}
429 
430 	err = pci_read_config_dword(rdev, AMD_PMC_SMU_INDEX_DATA, &val);
431 	if (err) {
432 		pci_dev_put(rdev);
433 		return pcibios_err_to_errno(err);
434 	}
435 
436 	base_addr_hi = val & AMD_PMC_BASE_ADDR_LO_MASK;
437 	pci_dev_put(rdev);
438 	base_addr = ((u64)base_addr_hi << 32 | base_addr_lo);
439 
440 	dev->regbase = devm_ioremap(dev->dev, base_addr + AMD_PMC_BASE_ADDR_OFFSET,
441 				    AMD_PMC_MAPPING_SIZE);
442 	if (!dev->regbase)
443 		return -ENOMEM;
444 
445 	mutex_init(&dev->lock);
446 
447 	/* Use FCH registers to get the S0ix stats */
448 	base_addr_lo = FCH_BASE_PHY_ADDR_LOW;
449 	base_addr_hi = FCH_BASE_PHY_ADDR_HIGH;
450 	fch_phys_addr = ((u64)base_addr_hi << 32 | base_addr_lo);
451 	dev->fch_virt_addr = devm_ioremap(dev->dev, fch_phys_addr, FCH_SSC_MAPPING_SIZE);
452 	if (!dev->fch_virt_addr)
453 		return -ENOMEM;
454 
455 	/* Use SMU to get the s0i3 debug stats */
456 	err = amd_pmc_setup_smu_logging(dev);
457 	if (err)
458 		dev_err(dev->dev, "SMU debugging info not supported on this platform\n");
459 
460 	platform_set_drvdata(pdev, dev);
461 	amd_pmc_dbgfs_register(dev);
462 	return 0;
463 }
464 
amd_pmc_remove(struct platform_device * pdev)465 static int amd_pmc_remove(struct platform_device *pdev)
466 {
467 	struct amd_pmc_dev *dev = platform_get_drvdata(pdev);
468 
469 	amd_pmc_dbgfs_unregister(dev);
470 	mutex_destroy(&dev->lock);
471 	return 0;
472 }
473 
474 static const struct acpi_device_id amd_pmc_acpi_ids[] = {
475 	{"AMDI0005", 0},
476 	{"AMDI0006", 0},
477 	{"AMDI0007", 0},
478 	{"AMD0004", 0},
479 	{"AMD0005", 0},
480 	{ }
481 };
482 MODULE_DEVICE_TABLE(acpi, amd_pmc_acpi_ids);
483 
484 static struct platform_driver amd_pmc_driver = {
485 	.driver = {
486 		.name = "amd_pmc",
487 		.acpi_match_table = amd_pmc_acpi_ids,
488 		.pm = &amd_pmc_pm_ops,
489 	},
490 	.probe = amd_pmc_probe,
491 	.remove = amd_pmc_remove,
492 };
493 module_platform_driver(amd_pmc_driver);
494 
495 MODULE_LICENSE("GPL v2");
496 MODULE_DESCRIPTION("AMD PMC Driver");
497