xref: /openbmc/linux/drivers/acpi/acpi_lpss.c (revision ea47eed33a3fe3d919e6e3cf4e4eb5507b817188)
1 /*
2  * ACPI support for Intel Lynxpoint LPSS.
3  *
4  * Copyright (C) 2013, Intel Corporation
5  * Authors: Mika Westerberg <mika.westerberg@linux.intel.com>
6  *          Rafael J. Wysocki <rafael.j.wysocki@intel.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #include <linux/acpi.h>
14 #include <linux/clkdev.h>
15 #include <linux/clk-provider.h>
16 #include <linux/err.h>
17 #include <linux/io.h>
18 #include <linux/mutex.h>
19 #include <linux/platform_device.h>
20 #include <linux/platform_data/clk-lpss.h>
21 #include <linux/platform_data/x86/pmc_atom.h>
22 #include <linux/pm_domain.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/pwm.h>
25 #include <linux/delay.h>
26 
27 #include "internal.h"
28 
29 ACPI_MODULE_NAME("acpi_lpss");
30 
31 #ifdef CONFIG_X86_INTEL_LPSS
32 
33 #include <asm/cpu_device_id.h>
34 #include <asm/intel-family.h>
35 #include <asm/iosf_mbi.h>
36 
37 #define LPSS_ADDR(desc) ((unsigned long)&desc)
38 
39 #define LPSS_CLK_SIZE	0x04
40 #define LPSS_LTR_SIZE	0x18
41 
42 /* Offsets relative to LPSS_PRIVATE_OFFSET */
43 #define LPSS_CLK_DIVIDER_DEF_MASK	(BIT(1) | BIT(16))
44 #define LPSS_RESETS			0x04
45 #define LPSS_RESETS_RESET_FUNC		BIT(0)
46 #define LPSS_RESETS_RESET_APB		BIT(1)
47 #define LPSS_GENERAL			0x08
48 #define LPSS_GENERAL_LTR_MODE_SW	BIT(2)
49 #define LPSS_GENERAL_UART_RTS_OVRD	BIT(3)
50 #define LPSS_SW_LTR			0x10
51 #define LPSS_AUTO_LTR			0x14
52 #define LPSS_LTR_SNOOP_REQ		BIT(15)
53 #define LPSS_LTR_SNOOP_MASK		0x0000FFFF
54 #define LPSS_LTR_SNOOP_LAT_1US		0x800
55 #define LPSS_LTR_SNOOP_LAT_32US		0xC00
56 #define LPSS_LTR_SNOOP_LAT_SHIFT	5
57 #define LPSS_LTR_SNOOP_LAT_CUTOFF	3000
58 #define LPSS_LTR_MAX_VAL		0x3FF
59 #define LPSS_TX_INT			0x20
60 #define LPSS_TX_INT_MASK		BIT(1)
61 
62 #define LPSS_PRV_REG_COUNT		9
63 
64 /* LPSS Flags */
65 #define LPSS_CLK			BIT(0)
66 #define LPSS_CLK_GATE			BIT(1)
67 #define LPSS_CLK_DIVIDER		BIT(2)
68 #define LPSS_LTR			BIT(3)
69 #define LPSS_SAVE_CTX			BIT(4)
70 #define LPSS_NO_D3_DELAY		BIT(5)
71 
72 /* Crystal Cove PMIC shares same ACPI ID between different platforms */
73 #define BYT_CRC_HRV			2
74 #define CHT_CRC_HRV			3
75 
76 struct lpss_private_data;
77 
78 struct lpss_device_desc {
79 	unsigned int flags;
80 	const char *clk_con_id;
81 	unsigned int prv_offset;
82 	size_t prv_size_override;
83 	struct property_entry *properties;
84 	void (*setup)(struct lpss_private_data *pdata);
85 };
86 
87 static const struct lpss_device_desc lpss_dma_desc = {
88 	.flags = LPSS_CLK,
89 };
90 
91 struct lpss_private_data {
92 	struct acpi_device *adev;
93 	void __iomem *mmio_base;
94 	resource_size_t mmio_size;
95 	unsigned int fixed_clk_rate;
96 	struct clk *clk;
97 	const struct lpss_device_desc *dev_desc;
98 	u32 prv_reg_ctx[LPSS_PRV_REG_COUNT];
99 };
100 
101 /* LPSS run time quirks */
102 static unsigned int lpss_quirks;
103 
104 /*
105  * LPSS_QUIRK_ALWAYS_POWER_ON: override power state for LPSS DMA device.
106  *
107  * The LPSS DMA controller has neither _PS0 nor _PS3 method. Moreover
108  * it can be powered off automatically whenever the last LPSS device goes down.
109  * In case of no power any access to the DMA controller will hang the system.
110  * The behaviour is reproduced on some HP laptops based on Intel BayTrail as
111  * well as on ASuS T100TA transformer.
112  *
113  * This quirk overrides power state of entire LPSS island to keep DMA powered
114  * on whenever we have at least one other device in use.
115  */
116 #define LPSS_QUIRK_ALWAYS_POWER_ON	BIT(0)
117 
118 /* UART Component Parameter Register */
119 #define LPSS_UART_CPR			0xF4
120 #define LPSS_UART_CPR_AFCE		BIT(4)
121 
122 static void lpss_uart_setup(struct lpss_private_data *pdata)
123 {
124 	unsigned int offset;
125 	u32 val;
126 
127 	offset = pdata->dev_desc->prv_offset + LPSS_TX_INT;
128 	val = readl(pdata->mmio_base + offset);
129 	writel(val | LPSS_TX_INT_MASK, pdata->mmio_base + offset);
130 
131 	val = readl(pdata->mmio_base + LPSS_UART_CPR);
132 	if (!(val & LPSS_UART_CPR_AFCE)) {
133 		offset = pdata->dev_desc->prv_offset + LPSS_GENERAL;
134 		val = readl(pdata->mmio_base + offset);
135 		val |= LPSS_GENERAL_UART_RTS_OVRD;
136 		writel(val, pdata->mmio_base + offset);
137 	}
138 }
139 
140 static void lpss_deassert_reset(struct lpss_private_data *pdata)
141 {
142 	unsigned int offset;
143 	u32 val;
144 
145 	offset = pdata->dev_desc->prv_offset + LPSS_RESETS;
146 	val = readl(pdata->mmio_base + offset);
147 	val |= LPSS_RESETS_RESET_APB | LPSS_RESETS_RESET_FUNC;
148 	writel(val, pdata->mmio_base + offset);
149 }
150 
151 /*
152  * BYT PWM used for backlight control by the i915 driver on systems without
153  * the Crystal Cove PMIC.
154  */
155 static struct pwm_lookup byt_pwm_lookup[] = {
156 	PWM_LOOKUP_WITH_MODULE("80860F09:00", 0, "0000:00:02.0",
157 			       "pwm_backlight", 0, PWM_POLARITY_NORMAL,
158 			       "pwm-lpss-platform"),
159 };
160 
161 static void byt_pwm_setup(struct lpss_private_data *pdata)
162 {
163 	struct acpi_device *adev = pdata->adev;
164 
165 	/* Only call pwm_add_table for the first PWM controller */
166 	if (!adev->pnp.unique_id || strcmp(adev->pnp.unique_id, "1"))
167 		return;
168 
169 	if (!acpi_dev_present("INT33FD", NULL, BYT_CRC_HRV))
170 		pwm_add_table(byt_pwm_lookup, ARRAY_SIZE(byt_pwm_lookup));
171 }
172 
173 #define LPSS_I2C_ENABLE			0x6c
174 
175 static void byt_i2c_setup(struct lpss_private_data *pdata)
176 {
177 	lpss_deassert_reset(pdata);
178 
179 	if (readl(pdata->mmio_base + pdata->dev_desc->prv_offset))
180 		pdata->fixed_clk_rate = 133000000;
181 
182 	writel(0, pdata->mmio_base + LPSS_I2C_ENABLE);
183 }
184 
185 /* BSW PWM used for backlight control by the i915 driver */
186 static struct pwm_lookup bsw_pwm_lookup[] = {
187 	PWM_LOOKUP_WITH_MODULE("80862288:00", 0, "0000:00:02.0",
188 			       "pwm_backlight", 0, PWM_POLARITY_NORMAL,
189 			       "pwm-lpss-platform"),
190 };
191 
192 static void bsw_pwm_setup(struct lpss_private_data *pdata)
193 {
194 	struct acpi_device *adev = pdata->adev;
195 
196 	/* Only call pwm_add_table for the first PWM controller */
197 	if (!adev->pnp.unique_id || strcmp(adev->pnp.unique_id, "1"))
198 		return;
199 
200 	pwm_add_table(bsw_pwm_lookup, ARRAY_SIZE(bsw_pwm_lookup));
201 }
202 
203 static const struct lpss_device_desc lpt_dev_desc = {
204 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR,
205 	.prv_offset = 0x800,
206 };
207 
208 static const struct lpss_device_desc lpt_i2c_dev_desc = {
209 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_LTR,
210 	.prv_offset = 0x800,
211 };
212 
213 static struct property_entry uart_properties[] = {
214 	PROPERTY_ENTRY_U32("reg-io-width", 4),
215 	PROPERTY_ENTRY_U32("reg-shift", 2),
216 	PROPERTY_ENTRY_BOOL("snps,uart-16550-compatible"),
217 	{ },
218 };
219 
220 static const struct lpss_device_desc lpt_uart_dev_desc = {
221 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR,
222 	.clk_con_id = "baudclk",
223 	.prv_offset = 0x800,
224 	.setup = lpss_uart_setup,
225 	.properties = uart_properties,
226 };
227 
228 static const struct lpss_device_desc lpt_sdio_dev_desc = {
229 	.flags = LPSS_LTR,
230 	.prv_offset = 0x1000,
231 	.prv_size_override = 0x1018,
232 };
233 
234 static const struct lpss_device_desc byt_pwm_dev_desc = {
235 	.flags = LPSS_SAVE_CTX,
236 	.prv_offset = 0x800,
237 	.setup = byt_pwm_setup,
238 };
239 
240 static const struct lpss_device_desc bsw_pwm_dev_desc = {
241 	.flags = LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
242 	.prv_offset = 0x800,
243 	.setup = bsw_pwm_setup,
244 };
245 
246 static const struct lpss_device_desc byt_uart_dev_desc = {
247 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
248 	.clk_con_id = "baudclk",
249 	.prv_offset = 0x800,
250 	.setup = lpss_uart_setup,
251 	.properties = uart_properties,
252 };
253 
254 static const struct lpss_device_desc bsw_uart_dev_desc = {
255 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
256 			| LPSS_NO_D3_DELAY,
257 	.clk_con_id = "baudclk",
258 	.prv_offset = 0x800,
259 	.setup = lpss_uart_setup,
260 	.properties = uart_properties,
261 };
262 
263 static const struct lpss_device_desc byt_spi_dev_desc = {
264 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
265 	.prv_offset = 0x400,
266 };
267 
268 static const struct lpss_device_desc byt_sdio_dev_desc = {
269 	.flags = LPSS_CLK,
270 };
271 
272 static const struct lpss_device_desc byt_i2c_dev_desc = {
273 	.flags = LPSS_CLK | LPSS_SAVE_CTX,
274 	.prv_offset = 0x800,
275 	.setup = byt_i2c_setup,
276 };
277 
278 static const struct lpss_device_desc bsw_i2c_dev_desc = {
279 	.flags = LPSS_CLK | LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
280 	.prv_offset = 0x800,
281 	.setup = byt_i2c_setup,
282 };
283 
284 static const struct lpss_device_desc bsw_spi_dev_desc = {
285 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
286 			| LPSS_NO_D3_DELAY,
287 	.prv_offset = 0x400,
288 	.setup = lpss_deassert_reset,
289 };
290 
291 #define ICPU(model)	{ X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, }
292 
293 static const struct x86_cpu_id lpss_cpu_ids[] = {
294 	ICPU(INTEL_FAM6_ATOM_SILVERMONT1),	/* Valleyview, Bay Trail */
295 	ICPU(INTEL_FAM6_ATOM_AIRMONT),	/* Braswell, Cherry Trail */
296 	{}
297 };
298 
299 #else
300 
301 #define LPSS_ADDR(desc) (0UL)
302 
303 #endif /* CONFIG_X86_INTEL_LPSS */
304 
305 static const struct acpi_device_id acpi_lpss_device_ids[] = {
306 	/* Generic LPSS devices */
307 	{ "INTL9C60", LPSS_ADDR(lpss_dma_desc) },
308 
309 	/* Lynxpoint LPSS devices */
310 	{ "INT33C0", LPSS_ADDR(lpt_dev_desc) },
311 	{ "INT33C1", LPSS_ADDR(lpt_dev_desc) },
312 	{ "INT33C2", LPSS_ADDR(lpt_i2c_dev_desc) },
313 	{ "INT33C3", LPSS_ADDR(lpt_i2c_dev_desc) },
314 	{ "INT33C4", LPSS_ADDR(lpt_uart_dev_desc) },
315 	{ "INT33C5", LPSS_ADDR(lpt_uart_dev_desc) },
316 	{ "INT33C6", LPSS_ADDR(lpt_sdio_dev_desc) },
317 	{ "INT33C7", },
318 
319 	/* BayTrail LPSS devices */
320 	{ "80860F09", LPSS_ADDR(byt_pwm_dev_desc) },
321 	{ "80860F0A", LPSS_ADDR(byt_uart_dev_desc) },
322 	{ "80860F0E", LPSS_ADDR(byt_spi_dev_desc) },
323 	{ "80860F14", LPSS_ADDR(byt_sdio_dev_desc) },
324 	{ "80860F41", LPSS_ADDR(byt_i2c_dev_desc) },
325 	{ "INT33B2", },
326 	{ "INT33FC", },
327 
328 	/* Braswell LPSS devices */
329 	{ "80862288", LPSS_ADDR(bsw_pwm_dev_desc) },
330 	{ "8086228A", LPSS_ADDR(bsw_uart_dev_desc) },
331 	{ "8086228E", LPSS_ADDR(bsw_spi_dev_desc) },
332 	{ "808622C1", LPSS_ADDR(bsw_i2c_dev_desc) },
333 
334 	/* Broadwell LPSS devices */
335 	{ "INT3430", LPSS_ADDR(lpt_dev_desc) },
336 	{ "INT3431", LPSS_ADDR(lpt_dev_desc) },
337 	{ "INT3432", LPSS_ADDR(lpt_i2c_dev_desc) },
338 	{ "INT3433", LPSS_ADDR(lpt_i2c_dev_desc) },
339 	{ "INT3434", LPSS_ADDR(lpt_uart_dev_desc) },
340 	{ "INT3435", LPSS_ADDR(lpt_uart_dev_desc) },
341 	{ "INT3436", LPSS_ADDR(lpt_sdio_dev_desc) },
342 	{ "INT3437", },
343 
344 	/* Wildcat Point LPSS devices */
345 	{ "INT3438", LPSS_ADDR(lpt_dev_desc) },
346 
347 	{ }
348 };
349 
350 #ifdef CONFIG_X86_INTEL_LPSS
351 
352 static int is_memory(struct acpi_resource *res, void *not_used)
353 {
354 	struct resource r;
355 	return !acpi_dev_resource_memory(res, &r);
356 }
357 
358 /* LPSS main clock device. */
359 static struct platform_device *lpss_clk_dev;
360 
361 static inline void lpt_register_clock_device(void)
362 {
363 	lpss_clk_dev = platform_device_register_simple("clk-lpt", -1, NULL, 0);
364 }
365 
366 static int register_device_clock(struct acpi_device *adev,
367 				 struct lpss_private_data *pdata)
368 {
369 	const struct lpss_device_desc *dev_desc = pdata->dev_desc;
370 	const char *devname = dev_name(&adev->dev);
371 	struct clk *clk;
372 	struct lpss_clk_data *clk_data;
373 	const char *parent, *clk_name;
374 	void __iomem *prv_base;
375 
376 	if (!lpss_clk_dev)
377 		lpt_register_clock_device();
378 
379 	clk_data = platform_get_drvdata(lpss_clk_dev);
380 	if (!clk_data)
381 		return -ENODEV;
382 	clk = clk_data->clk;
383 
384 	if (!pdata->mmio_base
385 	    || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE)
386 		return -ENODATA;
387 
388 	parent = clk_data->name;
389 	prv_base = pdata->mmio_base + dev_desc->prv_offset;
390 
391 	if (pdata->fixed_clk_rate) {
392 		clk = clk_register_fixed_rate(NULL, devname, parent, 0,
393 					      pdata->fixed_clk_rate);
394 		goto out;
395 	}
396 
397 	if (dev_desc->flags & LPSS_CLK_GATE) {
398 		clk = clk_register_gate(NULL, devname, parent, 0,
399 					prv_base, 0, 0, NULL);
400 		parent = devname;
401 	}
402 
403 	if (dev_desc->flags & LPSS_CLK_DIVIDER) {
404 		/* Prevent division by zero */
405 		if (!readl(prv_base))
406 			writel(LPSS_CLK_DIVIDER_DEF_MASK, prv_base);
407 
408 		clk_name = kasprintf(GFP_KERNEL, "%s-div", devname);
409 		if (!clk_name)
410 			return -ENOMEM;
411 		clk = clk_register_fractional_divider(NULL, clk_name, parent,
412 						      0, prv_base,
413 						      1, 15, 16, 15, 0, NULL);
414 		parent = clk_name;
415 
416 		clk_name = kasprintf(GFP_KERNEL, "%s-update", devname);
417 		if (!clk_name) {
418 			kfree(parent);
419 			return -ENOMEM;
420 		}
421 		clk = clk_register_gate(NULL, clk_name, parent,
422 					CLK_SET_RATE_PARENT | CLK_SET_RATE_GATE,
423 					prv_base, 31, 0, NULL);
424 		kfree(parent);
425 		kfree(clk_name);
426 	}
427 out:
428 	if (IS_ERR(clk))
429 		return PTR_ERR(clk);
430 
431 	pdata->clk = clk;
432 	clk_register_clkdev(clk, dev_desc->clk_con_id, devname);
433 	return 0;
434 }
435 
436 struct lpss_device_links {
437 	const char *supplier_hid;
438 	const char *supplier_uid;
439 	const char *consumer_hid;
440 	const char *consumer_uid;
441 	u32 flags;
442 };
443 
444 /*
445  * The _DEP method is used to identify dependencies but instead of creating
446  * device links for every handle in _DEP, only links in the following list are
447  * created. That is necessary because, in the general case, _DEP can refer to
448  * devices that might not have drivers, or that are on different buses, or where
449  * the supplier is not enumerated until after the consumer is probed.
450  */
451 static const struct lpss_device_links lpss_device_links[] = {
452 	{"808622C1", "7", "80860F14", "3", DL_FLAG_PM_RUNTIME},
453 };
454 
455 static bool hid_uid_match(const char *hid1, const char *uid1,
456 			  const char *hid2, const char *uid2)
457 {
458 	return !strcmp(hid1, hid2) && uid1 && uid2 && !strcmp(uid1, uid2);
459 }
460 
461 static bool acpi_lpss_is_supplier(struct acpi_device *adev,
462 				  const struct lpss_device_links *link)
463 {
464 	return hid_uid_match(acpi_device_hid(adev), acpi_device_uid(adev),
465 			     link->supplier_hid, link->supplier_uid);
466 }
467 
468 static bool acpi_lpss_is_consumer(struct acpi_device *adev,
469 				  const struct lpss_device_links *link)
470 {
471 	return hid_uid_match(acpi_device_hid(adev), acpi_device_uid(adev),
472 			     link->consumer_hid, link->consumer_uid);
473 }
474 
475 struct hid_uid {
476 	const char *hid;
477 	const char *uid;
478 };
479 
480 static int match_hid_uid(struct device *dev, void *data)
481 {
482 	struct acpi_device *adev = ACPI_COMPANION(dev);
483 	struct hid_uid *id = data;
484 
485 	if (!adev)
486 		return 0;
487 
488 	return hid_uid_match(acpi_device_hid(adev), acpi_device_uid(adev),
489 			     id->hid, id->uid);
490 }
491 
492 static struct device *acpi_lpss_find_device(const char *hid, const char *uid)
493 {
494 	struct hid_uid data = {
495 		.hid = hid,
496 		.uid = uid,
497 	};
498 
499 	return bus_find_device(&platform_bus_type, NULL, &data, match_hid_uid);
500 }
501 
502 static bool acpi_lpss_dep(struct acpi_device *adev, acpi_handle handle)
503 {
504 	struct acpi_handle_list dep_devices;
505 	acpi_status status;
506 	int i;
507 
508 	if (!acpi_has_method(adev->handle, "_DEP"))
509 		return false;
510 
511 	status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
512 					 &dep_devices);
513 	if (ACPI_FAILURE(status)) {
514 		dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
515 		return false;
516 	}
517 
518 	for (i = 0; i < dep_devices.count; i++) {
519 		if (dep_devices.handles[i] == handle)
520 			return true;
521 	}
522 
523 	return false;
524 }
525 
526 static void acpi_lpss_link_consumer(struct device *dev1,
527 				    const struct lpss_device_links *link)
528 {
529 	struct device *dev2;
530 
531 	dev2 = acpi_lpss_find_device(link->consumer_hid, link->consumer_uid);
532 	if (!dev2)
533 		return;
534 
535 	if (acpi_lpss_dep(ACPI_COMPANION(dev2), ACPI_HANDLE(dev1)))
536 		device_link_add(dev2, dev1, link->flags);
537 
538 	put_device(dev2);
539 }
540 
541 static void acpi_lpss_link_supplier(struct device *dev1,
542 				    const struct lpss_device_links *link)
543 {
544 	struct device *dev2;
545 
546 	dev2 = acpi_lpss_find_device(link->supplier_hid, link->supplier_uid);
547 	if (!dev2)
548 		return;
549 
550 	if (acpi_lpss_dep(ACPI_COMPANION(dev1), ACPI_HANDLE(dev2)))
551 		device_link_add(dev1, dev2, link->flags);
552 
553 	put_device(dev2);
554 }
555 
556 static void acpi_lpss_create_device_links(struct acpi_device *adev,
557 					  struct platform_device *pdev)
558 {
559 	int i;
560 
561 	for (i = 0; i < ARRAY_SIZE(lpss_device_links); i++) {
562 		const struct lpss_device_links *link = &lpss_device_links[i];
563 
564 		if (acpi_lpss_is_supplier(adev, link))
565 			acpi_lpss_link_consumer(&pdev->dev, link);
566 
567 		if (acpi_lpss_is_consumer(adev, link))
568 			acpi_lpss_link_supplier(&pdev->dev, link);
569 	}
570 }
571 
572 static int acpi_lpss_create_device(struct acpi_device *adev,
573 				   const struct acpi_device_id *id)
574 {
575 	const struct lpss_device_desc *dev_desc;
576 	struct lpss_private_data *pdata;
577 	struct resource_entry *rentry;
578 	struct list_head resource_list;
579 	struct platform_device *pdev;
580 	int ret;
581 
582 	dev_desc = (const struct lpss_device_desc *)id->driver_data;
583 	if (!dev_desc) {
584 		pdev = acpi_create_platform_device(adev, NULL);
585 		return IS_ERR_OR_NULL(pdev) ? PTR_ERR(pdev) : 1;
586 	}
587 	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
588 	if (!pdata)
589 		return -ENOMEM;
590 
591 	INIT_LIST_HEAD(&resource_list);
592 	ret = acpi_dev_get_resources(adev, &resource_list, is_memory, NULL);
593 	if (ret < 0)
594 		goto err_out;
595 
596 	list_for_each_entry(rentry, &resource_list, node)
597 		if (resource_type(rentry->res) == IORESOURCE_MEM) {
598 			if (dev_desc->prv_size_override)
599 				pdata->mmio_size = dev_desc->prv_size_override;
600 			else
601 				pdata->mmio_size = resource_size(rentry->res);
602 			pdata->mmio_base = ioremap(rentry->res->start,
603 						   pdata->mmio_size);
604 			break;
605 		}
606 
607 	acpi_dev_free_resource_list(&resource_list);
608 
609 	if (!pdata->mmio_base) {
610 		/* Avoid acpi_bus_attach() instantiating a pdev for this dev. */
611 		adev->pnp.type.platform_id = 0;
612 		/* Skip the device, but continue the namespace scan. */
613 		ret = 0;
614 		goto err_out;
615 	}
616 
617 	pdata->adev = adev;
618 	pdata->dev_desc = dev_desc;
619 
620 	if (dev_desc->setup)
621 		dev_desc->setup(pdata);
622 
623 	if (dev_desc->flags & LPSS_CLK) {
624 		ret = register_device_clock(adev, pdata);
625 		if (ret) {
626 			/* Skip the device, but continue the namespace scan. */
627 			ret = 0;
628 			goto err_out;
629 		}
630 	}
631 
632 	/*
633 	 * This works around a known issue in ACPI tables where LPSS devices
634 	 * have _PS0 and _PS3 without _PSC (and no power resources), so
635 	 * acpi_bus_init_power() will assume that the BIOS has put them into D0.
636 	 */
637 	ret = acpi_device_fix_up_power(adev);
638 	if (ret) {
639 		/* Skip the device, but continue the namespace scan. */
640 		ret = 0;
641 		goto err_out;
642 	}
643 
644 	adev->driver_data = pdata;
645 	pdev = acpi_create_platform_device(adev, dev_desc->properties);
646 	if (!IS_ERR_OR_NULL(pdev)) {
647 		acpi_lpss_create_device_links(adev, pdev);
648 		return 1;
649 	}
650 
651 	ret = PTR_ERR(pdev);
652 	adev->driver_data = NULL;
653 
654  err_out:
655 	kfree(pdata);
656 	return ret;
657 }
658 
659 static u32 __lpss_reg_read(struct lpss_private_data *pdata, unsigned int reg)
660 {
661 	return readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
662 }
663 
664 static void __lpss_reg_write(u32 val, struct lpss_private_data *pdata,
665 			     unsigned int reg)
666 {
667 	writel(val, pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
668 }
669 
670 static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val)
671 {
672 	struct acpi_device *adev;
673 	struct lpss_private_data *pdata;
674 	unsigned long flags;
675 	int ret;
676 
677 	ret = acpi_bus_get_device(ACPI_HANDLE(dev), &adev);
678 	if (WARN_ON(ret))
679 		return ret;
680 
681 	spin_lock_irqsave(&dev->power.lock, flags);
682 	if (pm_runtime_suspended(dev)) {
683 		ret = -EAGAIN;
684 		goto out;
685 	}
686 	pdata = acpi_driver_data(adev);
687 	if (WARN_ON(!pdata || !pdata->mmio_base)) {
688 		ret = -ENODEV;
689 		goto out;
690 	}
691 	*val = __lpss_reg_read(pdata, reg);
692 
693  out:
694 	spin_unlock_irqrestore(&dev->power.lock, flags);
695 	return ret;
696 }
697 
698 static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr,
699 			     char *buf)
700 {
701 	u32 ltr_value = 0;
702 	unsigned int reg;
703 	int ret;
704 
705 	reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR;
706 	ret = lpss_reg_read(dev, reg, &ltr_value);
707 	if (ret)
708 		return ret;
709 
710 	return snprintf(buf, PAGE_SIZE, "%08x\n", ltr_value);
711 }
712 
713 static ssize_t lpss_ltr_mode_show(struct device *dev,
714 				  struct device_attribute *attr, char *buf)
715 {
716 	u32 ltr_mode = 0;
717 	char *outstr;
718 	int ret;
719 
720 	ret = lpss_reg_read(dev, LPSS_GENERAL, &ltr_mode);
721 	if (ret)
722 		return ret;
723 
724 	outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto";
725 	return sprintf(buf, "%s\n", outstr);
726 }
727 
728 static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL);
729 static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL);
730 static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL);
731 
732 static struct attribute *lpss_attrs[] = {
733 	&dev_attr_auto_ltr.attr,
734 	&dev_attr_sw_ltr.attr,
735 	&dev_attr_ltr_mode.attr,
736 	NULL,
737 };
738 
739 static const struct attribute_group lpss_attr_group = {
740 	.attrs = lpss_attrs,
741 	.name = "lpss_ltr",
742 };
743 
744 static void acpi_lpss_set_ltr(struct device *dev, s32 val)
745 {
746 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
747 	u32 ltr_mode, ltr_val;
748 
749 	ltr_mode = __lpss_reg_read(pdata, LPSS_GENERAL);
750 	if (val < 0) {
751 		if (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) {
752 			ltr_mode &= ~LPSS_GENERAL_LTR_MODE_SW;
753 			__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
754 		}
755 		return;
756 	}
757 	ltr_val = __lpss_reg_read(pdata, LPSS_SW_LTR) & ~LPSS_LTR_SNOOP_MASK;
758 	if (val >= LPSS_LTR_SNOOP_LAT_CUTOFF) {
759 		ltr_val |= LPSS_LTR_SNOOP_LAT_32US;
760 		val = LPSS_LTR_MAX_VAL;
761 	} else if (val > LPSS_LTR_MAX_VAL) {
762 		ltr_val |= LPSS_LTR_SNOOP_LAT_32US | LPSS_LTR_SNOOP_REQ;
763 		val >>= LPSS_LTR_SNOOP_LAT_SHIFT;
764 	} else {
765 		ltr_val |= LPSS_LTR_SNOOP_LAT_1US | LPSS_LTR_SNOOP_REQ;
766 	}
767 	ltr_val |= val;
768 	__lpss_reg_write(ltr_val, pdata, LPSS_SW_LTR);
769 	if (!(ltr_mode & LPSS_GENERAL_LTR_MODE_SW)) {
770 		ltr_mode |= LPSS_GENERAL_LTR_MODE_SW;
771 		__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
772 	}
773 }
774 
775 #ifdef CONFIG_PM
776 /**
777  * acpi_lpss_save_ctx() - Save the private registers of LPSS device
778  * @dev: LPSS device
779  * @pdata: pointer to the private data of the LPSS device
780  *
781  * Most LPSS devices have private registers which may loose their context when
782  * the device is powered down. acpi_lpss_save_ctx() saves those registers into
783  * prv_reg_ctx array.
784  */
785 static void acpi_lpss_save_ctx(struct device *dev,
786 			       struct lpss_private_data *pdata)
787 {
788 	unsigned int i;
789 
790 	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
791 		unsigned long offset = i * sizeof(u32);
792 
793 		pdata->prv_reg_ctx[i] = __lpss_reg_read(pdata, offset);
794 		dev_dbg(dev, "saving 0x%08x from LPSS reg at offset 0x%02lx\n",
795 			pdata->prv_reg_ctx[i], offset);
796 	}
797 }
798 
799 /**
800  * acpi_lpss_restore_ctx() - Restore the private registers of LPSS device
801  * @dev: LPSS device
802  * @pdata: pointer to the private data of the LPSS device
803  *
804  * Restores the registers that were previously stored with acpi_lpss_save_ctx().
805  */
806 static void acpi_lpss_restore_ctx(struct device *dev,
807 				  struct lpss_private_data *pdata)
808 {
809 	unsigned int i;
810 
811 	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
812 		unsigned long offset = i * sizeof(u32);
813 
814 		__lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset);
815 		dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n",
816 			pdata->prv_reg_ctx[i], offset);
817 	}
818 }
819 
820 static void acpi_lpss_d3_to_d0_delay(struct lpss_private_data *pdata)
821 {
822 	/*
823 	 * The following delay is needed or the subsequent write operations may
824 	 * fail. The LPSS devices are actually PCI devices and the PCI spec
825 	 * expects 10ms delay before the device can be accessed after D3 to D0
826 	 * transition. However some platforms like BSW does not need this delay.
827 	 */
828 	unsigned int delay = 10;	/* default 10ms delay */
829 
830 	if (pdata->dev_desc->flags & LPSS_NO_D3_DELAY)
831 		delay = 0;
832 
833 	msleep(delay);
834 }
835 
836 static int acpi_lpss_activate(struct device *dev)
837 {
838 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
839 	int ret;
840 
841 	ret = acpi_dev_resume(dev);
842 	if (ret)
843 		return ret;
844 
845 	acpi_lpss_d3_to_d0_delay(pdata);
846 
847 	/*
848 	 * This is called only on ->probe() stage where a device is either in
849 	 * known state defined by BIOS or most likely powered off. Due to this
850 	 * we have to deassert reset line to be sure that ->probe() will
851 	 * recognize the device.
852 	 */
853 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
854 		lpss_deassert_reset(pdata);
855 
856 	return 0;
857 }
858 
859 static void acpi_lpss_dismiss(struct device *dev)
860 {
861 	acpi_dev_suspend(dev, false);
862 }
863 
864 /* IOSF SB for LPSS island */
865 #define LPSS_IOSF_UNIT_LPIOEP		0xA0
866 #define LPSS_IOSF_UNIT_LPIO1		0xAB
867 #define LPSS_IOSF_UNIT_LPIO2		0xAC
868 
869 #define LPSS_IOSF_PMCSR			0x84
870 #define LPSS_PMCSR_D0			0
871 #define LPSS_PMCSR_D3hot		3
872 #define LPSS_PMCSR_Dx_MASK		GENMASK(1, 0)
873 
874 #define LPSS_IOSF_GPIODEF0		0x154
875 #define LPSS_GPIODEF0_DMA1_D3		BIT(2)
876 #define LPSS_GPIODEF0_DMA2_D3		BIT(3)
877 #define LPSS_GPIODEF0_DMA_D3_MASK	GENMASK(3, 2)
878 #define LPSS_GPIODEF0_DMA_LLP		BIT(13)
879 
880 static DEFINE_MUTEX(lpss_iosf_mutex);
881 
882 static void lpss_iosf_enter_d3_state(void)
883 {
884 	u32 value1 = 0;
885 	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
886 	u32 value2 = LPSS_PMCSR_D3hot;
887 	u32 mask2 = LPSS_PMCSR_Dx_MASK;
888 	/*
889 	 * PMC provides an information about actual status of the LPSS devices.
890 	 * Here we read the values related to LPSS power island, i.e. LPSS
891 	 * devices, excluding both LPSS DMA controllers, along with SCC domain.
892 	 */
893 	u32 func_dis, d3_sts_0, pmc_status, pmc_mask = 0xfe000ffe;
894 	int ret;
895 
896 	ret = pmc_atom_read(PMC_FUNC_DIS, &func_dis);
897 	if (ret)
898 		return;
899 
900 	mutex_lock(&lpss_iosf_mutex);
901 
902 	ret = pmc_atom_read(PMC_D3_STS_0, &d3_sts_0);
903 	if (ret)
904 		goto exit;
905 
906 	/*
907 	 * Get the status of entire LPSS power island per device basis.
908 	 * Shutdown both LPSS DMA controllers if and only if all other devices
909 	 * are already in D3hot.
910 	 */
911 	pmc_status = (~(d3_sts_0 | func_dis)) & pmc_mask;
912 	if (pmc_status)
913 		goto exit;
914 
915 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
916 			LPSS_IOSF_PMCSR, value2, mask2);
917 
918 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
919 			LPSS_IOSF_PMCSR, value2, mask2);
920 
921 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
922 			LPSS_IOSF_GPIODEF0, value1, mask1);
923 exit:
924 	mutex_unlock(&lpss_iosf_mutex);
925 }
926 
927 static void lpss_iosf_exit_d3_state(void)
928 {
929 	u32 value1 = LPSS_GPIODEF0_DMA1_D3 | LPSS_GPIODEF0_DMA2_D3 |
930 		     LPSS_GPIODEF0_DMA_LLP;
931 	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
932 	u32 value2 = LPSS_PMCSR_D0;
933 	u32 mask2 = LPSS_PMCSR_Dx_MASK;
934 
935 	mutex_lock(&lpss_iosf_mutex);
936 
937 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
938 			LPSS_IOSF_GPIODEF0, value1, mask1);
939 
940 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
941 			LPSS_IOSF_PMCSR, value2, mask2);
942 
943 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
944 			LPSS_IOSF_PMCSR, value2, mask2);
945 
946 	mutex_unlock(&lpss_iosf_mutex);
947 }
948 
949 static int acpi_lpss_suspend(struct device *dev, bool wakeup)
950 {
951 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
952 	int ret;
953 
954 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
955 		acpi_lpss_save_ctx(dev, pdata);
956 
957 	ret = acpi_dev_suspend(dev, wakeup);
958 
959 	/*
960 	 * This call must be last in the sequence, otherwise PMC will return
961 	 * wrong status for devices being about to be powered off. See
962 	 * lpss_iosf_enter_d3_state() for further information.
963 	 */
964 	if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
965 		lpss_iosf_enter_d3_state();
966 
967 	return ret;
968 }
969 
970 static int acpi_lpss_resume(struct device *dev)
971 {
972 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
973 	int ret;
974 
975 	/*
976 	 * This call is kept first to be in symmetry with
977 	 * acpi_lpss_runtime_suspend() one.
978 	 */
979 	if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
980 		lpss_iosf_exit_d3_state();
981 
982 	ret = acpi_dev_resume(dev);
983 	if (ret)
984 		return ret;
985 
986 	acpi_lpss_d3_to_d0_delay(pdata);
987 
988 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
989 		acpi_lpss_restore_ctx(dev, pdata);
990 
991 	return 0;
992 }
993 
994 #ifdef CONFIG_PM_SLEEP
995 static int acpi_lpss_suspend_late(struct device *dev)
996 {
997 	int ret;
998 
999 	if (dev_pm_smart_suspend_and_suspended(dev))
1000 		return 0;
1001 
1002 	ret = pm_generic_suspend_late(dev);
1003 	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
1004 }
1005 
1006 static int acpi_lpss_resume_early(struct device *dev)
1007 {
1008 	int ret = acpi_lpss_resume(dev);
1009 
1010 	return ret ? ret : pm_generic_resume_early(dev);
1011 }
1012 #endif /* CONFIG_PM_SLEEP */
1013 
1014 static int acpi_lpss_runtime_suspend(struct device *dev)
1015 {
1016 	int ret = pm_generic_runtime_suspend(dev);
1017 
1018 	return ret ? ret : acpi_lpss_suspend(dev, true);
1019 }
1020 
1021 static int acpi_lpss_runtime_resume(struct device *dev)
1022 {
1023 	int ret = acpi_lpss_resume(dev);
1024 
1025 	return ret ? ret : pm_generic_runtime_resume(dev);
1026 }
1027 #endif /* CONFIG_PM */
1028 
1029 static struct dev_pm_domain acpi_lpss_pm_domain = {
1030 #ifdef CONFIG_PM
1031 	.activate = acpi_lpss_activate,
1032 	.dismiss = acpi_lpss_dismiss,
1033 #endif
1034 	.ops = {
1035 #ifdef CONFIG_PM
1036 #ifdef CONFIG_PM_SLEEP
1037 		.prepare = acpi_subsys_prepare,
1038 		.complete = acpi_subsys_complete,
1039 		.suspend = acpi_subsys_suspend,
1040 		.suspend_late = acpi_lpss_suspend_late,
1041 		.suspend_noirq = acpi_subsys_suspend_noirq,
1042 		.resume_noirq = acpi_subsys_resume_noirq,
1043 		.resume_early = acpi_lpss_resume_early,
1044 		.freeze = acpi_subsys_freeze,
1045 		.freeze_late = acpi_subsys_freeze_late,
1046 		.freeze_noirq = acpi_subsys_freeze_noirq,
1047 		.thaw_noirq = acpi_subsys_thaw_noirq,
1048 		.poweroff = acpi_subsys_suspend,
1049 		.poweroff_late = acpi_lpss_suspend_late,
1050 		.poweroff_noirq = acpi_subsys_suspend_noirq,
1051 		.restore_noirq = acpi_subsys_resume_noirq,
1052 		.restore_early = acpi_lpss_resume_early,
1053 #endif
1054 		.runtime_suspend = acpi_lpss_runtime_suspend,
1055 		.runtime_resume = acpi_lpss_runtime_resume,
1056 #endif
1057 	},
1058 };
1059 
1060 static int acpi_lpss_platform_notify(struct notifier_block *nb,
1061 				     unsigned long action, void *data)
1062 {
1063 	struct platform_device *pdev = to_platform_device(data);
1064 	struct lpss_private_data *pdata;
1065 	struct acpi_device *adev;
1066 	const struct acpi_device_id *id;
1067 
1068 	id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev);
1069 	if (!id || !id->driver_data)
1070 		return 0;
1071 
1072 	if (acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev))
1073 		return 0;
1074 
1075 	pdata = acpi_driver_data(adev);
1076 	if (!pdata)
1077 		return 0;
1078 
1079 	if (pdata->mmio_base &&
1080 	    pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) {
1081 		dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n");
1082 		return 0;
1083 	}
1084 
1085 	switch (action) {
1086 	case BUS_NOTIFY_BIND_DRIVER:
1087 		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1088 		break;
1089 	case BUS_NOTIFY_DRIVER_NOT_BOUND:
1090 	case BUS_NOTIFY_UNBOUND_DRIVER:
1091 		dev_pm_domain_set(&pdev->dev, NULL);
1092 		break;
1093 	case BUS_NOTIFY_ADD_DEVICE:
1094 		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1095 		if (pdata->dev_desc->flags & LPSS_LTR)
1096 			return sysfs_create_group(&pdev->dev.kobj,
1097 						  &lpss_attr_group);
1098 		break;
1099 	case BUS_NOTIFY_DEL_DEVICE:
1100 		if (pdata->dev_desc->flags & LPSS_LTR)
1101 			sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group);
1102 		dev_pm_domain_set(&pdev->dev, NULL);
1103 		break;
1104 	default:
1105 		break;
1106 	}
1107 
1108 	return 0;
1109 }
1110 
1111 static struct notifier_block acpi_lpss_nb = {
1112 	.notifier_call = acpi_lpss_platform_notify,
1113 };
1114 
1115 static void acpi_lpss_bind(struct device *dev)
1116 {
1117 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1118 
1119 	if (!pdata || !pdata->mmio_base || !(pdata->dev_desc->flags & LPSS_LTR))
1120 		return;
1121 
1122 	if (pdata->mmio_size >= pdata->dev_desc->prv_offset + LPSS_LTR_SIZE)
1123 		dev->power.set_latency_tolerance = acpi_lpss_set_ltr;
1124 	else
1125 		dev_err(dev, "MMIO size insufficient to access LTR\n");
1126 }
1127 
1128 static void acpi_lpss_unbind(struct device *dev)
1129 {
1130 	dev->power.set_latency_tolerance = NULL;
1131 }
1132 
1133 static struct acpi_scan_handler lpss_handler = {
1134 	.ids = acpi_lpss_device_ids,
1135 	.attach = acpi_lpss_create_device,
1136 	.bind = acpi_lpss_bind,
1137 	.unbind = acpi_lpss_unbind,
1138 };
1139 
1140 void __init acpi_lpss_init(void)
1141 {
1142 	const struct x86_cpu_id *id;
1143 	int ret;
1144 
1145 	ret = lpt_clk_init();
1146 	if (ret)
1147 		return;
1148 
1149 	id = x86_match_cpu(lpss_cpu_ids);
1150 	if (id)
1151 		lpss_quirks |= LPSS_QUIRK_ALWAYS_POWER_ON;
1152 
1153 	bus_register_notifier(&platform_bus_type, &acpi_lpss_nb);
1154 	acpi_scan_add_handler(&lpss_handler);
1155 }
1156 
1157 #else
1158 
1159 static struct acpi_scan_handler lpss_handler = {
1160 	.ids = acpi_lpss_device_ids,
1161 };
1162 
1163 void __init acpi_lpss_init(void)
1164 {
1165 	acpi_scan_add_handler(&lpss_handler);
1166 }
1167 
1168 #endif /* CONFIG_X86_INTEL_LPSS */
1169