xref: /openbmc/linux/drivers/acpi/acpi_lpss.c (revision d623f60d)
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/suspend.h>
26 #include <linux/delay.h>
27 
28 #include "internal.h"
29 
30 ACPI_MODULE_NAME("acpi_lpss");
31 
32 #ifdef CONFIG_X86_INTEL_LPSS
33 
34 #include <asm/cpu_device_id.h>
35 #include <asm/intel-family.h>
36 #include <asm/iosf_mbi.h>
37 
38 #define LPSS_ADDR(desc) ((unsigned long)&desc)
39 
40 #define LPSS_CLK_SIZE	0x04
41 #define LPSS_LTR_SIZE	0x18
42 
43 /* Offsets relative to LPSS_PRIVATE_OFFSET */
44 #define LPSS_CLK_DIVIDER_DEF_MASK	(BIT(1) | BIT(16))
45 #define LPSS_RESETS			0x04
46 #define LPSS_RESETS_RESET_FUNC		BIT(0)
47 #define LPSS_RESETS_RESET_APB		BIT(1)
48 #define LPSS_GENERAL			0x08
49 #define LPSS_GENERAL_LTR_MODE_SW	BIT(2)
50 #define LPSS_GENERAL_UART_RTS_OVRD	BIT(3)
51 #define LPSS_SW_LTR			0x10
52 #define LPSS_AUTO_LTR			0x14
53 #define LPSS_LTR_SNOOP_REQ		BIT(15)
54 #define LPSS_LTR_SNOOP_MASK		0x0000FFFF
55 #define LPSS_LTR_SNOOP_LAT_1US		0x800
56 #define LPSS_LTR_SNOOP_LAT_32US		0xC00
57 #define LPSS_LTR_SNOOP_LAT_SHIFT	5
58 #define LPSS_LTR_SNOOP_LAT_CUTOFF	3000
59 #define LPSS_LTR_MAX_VAL		0x3FF
60 #define LPSS_TX_INT			0x20
61 #define LPSS_TX_INT_MASK		BIT(1)
62 
63 #define LPSS_PRV_REG_COUNT		9
64 
65 /* LPSS Flags */
66 #define LPSS_CLK			BIT(0)
67 #define LPSS_CLK_GATE			BIT(1)
68 #define LPSS_CLK_DIVIDER		BIT(2)
69 #define LPSS_LTR			BIT(3)
70 #define LPSS_SAVE_CTX			BIT(4)
71 #define LPSS_NO_D3_DELAY		BIT(5)
72 
73 /* Crystal Cove PMIC shares same ACPI ID between different platforms */
74 #define BYT_CRC_HRV			2
75 #define CHT_CRC_HRV			3
76 
77 struct lpss_private_data;
78 
79 struct lpss_device_desc {
80 	unsigned int flags;
81 	const char *clk_con_id;
82 	unsigned int prv_offset;
83 	size_t prv_size_override;
84 	struct property_entry *properties;
85 	void (*setup)(struct lpss_private_data *pdata);
86 };
87 
88 static const struct lpss_device_desc lpss_dma_desc = {
89 	.flags = LPSS_CLK,
90 };
91 
92 struct lpss_private_data {
93 	struct acpi_device *adev;
94 	void __iomem *mmio_base;
95 	resource_size_t mmio_size;
96 	unsigned int fixed_clk_rate;
97 	struct clk *clk;
98 	const struct lpss_device_desc *dev_desc;
99 	u32 prv_reg_ctx[LPSS_PRV_REG_COUNT];
100 };
101 
102 /* LPSS run time quirks */
103 static unsigned int lpss_quirks;
104 
105 /*
106  * LPSS_QUIRK_ALWAYS_POWER_ON: override power state for LPSS DMA device.
107  *
108  * The LPSS DMA controller has neither _PS0 nor _PS3 method. Moreover
109  * it can be powered off automatically whenever the last LPSS device goes down.
110  * In case of no power any access to the DMA controller will hang the system.
111  * The behaviour is reproduced on some HP laptops based on Intel BayTrail as
112  * well as on ASuS T100TA transformer.
113  *
114  * This quirk overrides power state of entire LPSS island to keep DMA powered
115  * on whenever we have at least one other device in use.
116  */
117 #define LPSS_QUIRK_ALWAYS_POWER_ON	BIT(0)
118 
119 /* UART Component Parameter Register */
120 #define LPSS_UART_CPR			0xF4
121 #define LPSS_UART_CPR_AFCE		BIT(4)
122 
123 static void lpss_uart_setup(struct lpss_private_data *pdata)
124 {
125 	unsigned int offset;
126 	u32 val;
127 
128 	offset = pdata->dev_desc->prv_offset + LPSS_TX_INT;
129 	val = readl(pdata->mmio_base + offset);
130 	writel(val | LPSS_TX_INT_MASK, pdata->mmio_base + offset);
131 
132 	val = readl(pdata->mmio_base + LPSS_UART_CPR);
133 	if (!(val & LPSS_UART_CPR_AFCE)) {
134 		offset = pdata->dev_desc->prv_offset + LPSS_GENERAL;
135 		val = readl(pdata->mmio_base + offset);
136 		val |= LPSS_GENERAL_UART_RTS_OVRD;
137 		writel(val, pdata->mmio_base + offset);
138 	}
139 }
140 
141 static void lpss_deassert_reset(struct lpss_private_data *pdata)
142 {
143 	unsigned int offset;
144 	u32 val;
145 
146 	offset = pdata->dev_desc->prv_offset + LPSS_RESETS;
147 	val = readl(pdata->mmio_base + offset);
148 	val |= LPSS_RESETS_RESET_APB | LPSS_RESETS_RESET_FUNC;
149 	writel(val, pdata->mmio_base + offset);
150 }
151 
152 /*
153  * BYT PWM used for backlight control by the i915 driver on systems without
154  * the Crystal Cove PMIC.
155  */
156 static struct pwm_lookup byt_pwm_lookup[] = {
157 	PWM_LOOKUP_WITH_MODULE("80860F09:00", 0, "0000:00:02.0",
158 			       "pwm_backlight", 0, PWM_POLARITY_NORMAL,
159 			       "pwm-lpss-platform"),
160 };
161 
162 static void byt_pwm_setup(struct lpss_private_data *pdata)
163 {
164 	struct acpi_device *adev = pdata->adev;
165 
166 	/* Only call pwm_add_table for the first PWM controller */
167 	if (!adev->pnp.unique_id || strcmp(adev->pnp.unique_id, "1"))
168 		return;
169 
170 	if (!acpi_dev_present("INT33FD", NULL, BYT_CRC_HRV))
171 		pwm_add_table(byt_pwm_lookup, ARRAY_SIZE(byt_pwm_lookup));
172 }
173 
174 #define LPSS_I2C_ENABLE			0x6c
175 
176 static void byt_i2c_setup(struct lpss_private_data *pdata)
177 {
178 	lpss_deassert_reset(pdata);
179 
180 	if (readl(pdata->mmio_base + pdata->dev_desc->prv_offset))
181 		pdata->fixed_clk_rate = 133000000;
182 
183 	writel(0, pdata->mmio_base + LPSS_I2C_ENABLE);
184 }
185 
186 /* BSW PWM used for backlight control by the i915 driver */
187 static struct pwm_lookup bsw_pwm_lookup[] = {
188 	PWM_LOOKUP_WITH_MODULE("80862288:00", 0, "0000:00:02.0",
189 			       "pwm_backlight", 0, PWM_POLARITY_NORMAL,
190 			       "pwm-lpss-platform"),
191 };
192 
193 static void bsw_pwm_setup(struct lpss_private_data *pdata)
194 {
195 	struct acpi_device *adev = pdata->adev;
196 
197 	/* Only call pwm_add_table for the first PWM controller */
198 	if (!adev->pnp.unique_id || strcmp(adev->pnp.unique_id, "1"))
199 		return;
200 
201 	pwm_add_table(bsw_pwm_lookup, ARRAY_SIZE(bsw_pwm_lookup));
202 }
203 
204 static const struct lpss_device_desc lpt_dev_desc = {
205 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR,
206 	.prv_offset = 0x800,
207 };
208 
209 static const struct lpss_device_desc lpt_i2c_dev_desc = {
210 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_LTR,
211 	.prv_offset = 0x800,
212 };
213 
214 static struct property_entry uart_properties[] = {
215 	PROPERTY_ENTRY_U32("reg-io-width", 4),
216 	PROPERTY_ENTRY_U32("reg-shift", 2),
217 	PROPERTY_ENTRY_BOOL("snps,uart-16550-compatible"),
218 	{ },
219 };
220 
221 static const struct lpss_device_desc lpt_uart_dev_desc = {
222 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR,
223 	.clk_con_id = "baudclk",
224 	.prv_offset = 0x800,
225 	.setup = lpss_uart_setup,
226 	.properties = uart_properties,
227 };
228 
229 static const struct lpss_device_desc lpt_sdio_dev_desc = {
230 	.flags = LPSS_LTR,
231 	.prv_offset = 0x1000,
232 	.prv_size_override = 0x1018,
233 };
234 
235 static const struct lpss_device_desc byt_pwm_dev_desc = {
236 	.flags = LPSS_SAVE_CTX,
237 	.prv_offset = 0x800,
238 	.setup = byt_pwm_setup,
239 };
240 
241 static const struct lpss_device_desc bsw_pwm_dev_desc = {
242 	.flags = LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
243 	.prv_offset = 0x800,
244 	.setup = bsw_pwm_setup,
245 };
246 
247 static const struct lpss_device_desc byt_uart_dev_desc = {
248 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
249 	.clk_con_id = "baudclk",
250 	.prv_offset = 0x800,
251 	.setup = lpss_uart_setup,
252 	.properties = uart_properties,
253 };
254 
255 static const struct lpss_device_desc bsw_uart_dev_desc = {
256 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
257 			| LPSS_NO_D3_DELAY,
258 	.clk_con_id = "baudclk",
259 	.prv_offset = 0x800,
260 	.setup = lpss_uart_setup,
261 	.properties = uart_properties,
262 };
263 
264 static const struct lpss_device_desc byt_spi_dev_desc = {
265 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
266 	.prv_offset = 0x400,
267 };
268 
269 static const struct lpss_device_desc byt_sdio_dev_desc = {
270 	.flags = LPSS_CLK,
271 };
272 
273 static const struct lpss_device_desc byt_i2c_dev_desc = {
274 	.flags = LPSS_CLK | LPSS_SAVE_CTX,
275 	.prv_offset = 0x800,
276 	.setup = byt_i2c_setup,
277 };
278 
279 static const struct lpss_device_desc bsw_i2c_dev_desc = {
280 	.flags = LPSS_CLK | LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
281 	.prv_offset = 0x800,
282 	.setup = byt_i2c_setup,
283 };
284 
285 static const struct lpss_device_desc bsw_spi_dev_desc = {
286 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
287 			| LPSS_NO_D3_DELAY,
288 	.prv_offset = 0x400,
289 	.setup = lpss_deassert_reset,
290 };
291 
292 #define ICPU(model)	{ X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, }
293 
294 static const struct x86_cpu_id lpss_cpu_ids[] = {
295 	ICPU(INTEL_FAM6_ATOM_SILVERMONT1),	/* Valleyview, Bay Trail */
296 	ICPU(INTEL_FAM6_ATOM_AIRMONT),	/* Braswell, Cherry Trail */
297 	{}
298 };
299 
300 #else
301 
302 #define LPSS_ADDR(desc) (0UL)
303 
304 #endif /* CONFIG_X86_INTEL_LPSS */
305 
306 static const struct acpi_device_id acpi_lpss_device_ids[] = {
307 	/* Generic LPSS devices */
308 	{ "INTL9C60", LPSS_ADDR(lpss_dma_desc) },
309 
310 	/* Lynxpoint LPSS devices */
311 	{ "INT33C0", LPSS_ADDR(lpt_dev_desc) },
312 	{ "INT33C1", LPSS_ADDR(lpt_dev_desc) },
313 	{ "INT33C2", LPSS_ADDR(lpt_i2c_dev_desc) },
314 	{ "INT33C3", LPSS_ADDR(lpt_i2c_dev_desc) },
315 	{ "INT33C4", LPSS_ADDR(lpt_uart_dev_desc) },
316 	{ "INT33C5", LPSS_ADDR(lpt_uart_dev_desc) },
317 	{ "INT33C6", LPSS_ADDR(lpt_sdio_dev_desc) },
318 	{ "INT33C7", },
319 
320 	/* BayTrail LPSS devices */
321 	{ "80860F09", LPSS_ADDR(byt_pwm_dev_desc) },
322 	{ "80860F0A", LPSS_ADDR(byt_uart_dev_desc) },
323 	{ "80860F0E", LPSS_ADDR(byt_spi_dev_desc) },
324 	{ "80860F14", LPSS_ADDR(byt_sdio_dev_desc) },
325 	{ "80860F41", LPSS_ADDR(byt_i2c_dev_desc) },
326 	{ "INT33B2", },
327 	{ "INT33FC", },
328 
329 	/* Braswell LPSS devices */
330 	{ "80862288", LPSS_ADDR(bsw_pwm_dev_desc) },
331 	{ "8086228A", LPSS_ADDR(bsw_uart_dev_desc) },
332 	{ "8086228E", LPSS_ADDR(bsw_spi_dev_desc) },
333 	{ "808622C1", LPSS_ADDR(bsw_i2c_dev_desc) },
334 
335 	/* Broadwell LPSS devices */
336 	{ "INT3430", LPSS_ADDR(lpt_dev_desc) },
337 	{ "INT3431", LPSS_ADDR(lpt_dev_desc) },
338 	{ "INT3432", LPSS_ADDR(lpt_i2c_dev_desc) },
339 	{ "INT3433", LPSS_ADDR(lpt_i2c_dev_desc) },
340 	{ "INT3434", LPSS_ADDR(lpt_uart_dev_desc) },
341 	{ "INT3435", LPSS_ADDR(lpt_uart_dev_desc) },
342 	{ "INT3436", LPSS_ADDR(lpt_sdio_dev_desc) },
343 	{ "INT3437", },
344 
345 	/* Wildcat Point LPSS devices */
346 	{ "INT3438", LPSS_ADDR(lpt_dev_desc) },
347 
348 	{ }
349 };
350 
351 #ifdef CONFIG_X86_INTEL_LPSS
352 
353 static int is_memory(struct acpi_resource *res, void *not_used)
354 {
355 	struct resource r;
356 	return !acpi_dev_resource_memory(res, &r);
357 }
358 
359 /* LPSS main clock device. */
360 static struct platform_device *lpss_clk_dev;
361 
362 static inline void lpt_register_clock_device(void)
363 {
364 	lpss_clk_dev = platform_device_register_simple("clk-lpt", -1, NULL, 0);
365 }
366 
367 static int register_device_clock(struct acpi_device *adev,
368 				 struct lpss_private_data *pdata)
369 {
370 	const struct lpss_device_desc *dev_desc = pdata->dev_desc;
371 	const char *devname = dev_name(&adev->dev);
372 	struct clk *clk;
373 	struct lpss_clk_data *clk_data;
374 	const char *parent, *clk_name;
375 	void __iomem *prv_base;
376 
377 	if (!lpss_clk_dev)
378 		lpt_register_clock_device();
379 
380 	clk_data = platform_get_drvdata(lpss_clk_dev);
381 	if (!clk_data)
382 		return -ENODEV;
383 	clk = clk_data->clk;
384 
385 	if (!pdata->mmio_base
386 	    || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE)
387 		return -ENODATA;
388 
389 	parent = clk_data->name;
390 	prv_base = pdata->mmio_base + dev_desc->prv_offset;
391 
392 	if (pdata->fixed_clk_rate) {
393 		clk = clk_register_fixed_rate(NULL, devname, parent, 0,
394 					      pdata->fixed_clk_rate);
395 		goto out;
396 	}
397 
398 	if (dev_desc->flags & LPSS_CLK_GATE) {
399 		clk = clk_register_gate(NULL, devname, parent, 0,
400 					prv_base, 0, 0, NULL);
401 		parent = devname;
402 	}
403 
404 	if (dev_desc->flags & LPSS_CLK_DIVIDER) {
405 		/* Prevent division by zero */
406 		if (!readl(prv_base))
407 			writel(LPSS_CLK_DIVIDER_DEF_MASK, prv_base);
408 
409 		clk_name = kasprintf(GFP_KERNEL, "%s-div", devname);
410 		if (!clk_name)
411 			return -ENOMEM;
412 		clk = clk_register_fractional_divider(NULL, clk_name, parent,
413 						      0, prv_base,
414 						      1, 15, 16, 15, 0, NULL);
415 		parent = clk_name;
416 
417 		clk_name = kasprintf(GFP_KERNEL, "%s-update", devname);
418 		if (!clk_name) {
419 			kfree(parent);
420 			return -ENOMEM;
421 		}
422 		clk = clk_register_gate(NULL, clk_name, parent,
423 					CLK_SET_RATE_PARENT | CLK_SET_RATE_GATE,
424 					prv_base, 31, 0, NULL);
425 		kfree(parent);
426 		kfree(clk_name);
427 	}
428 out:
429 	if (IS_ERR(clk))
430 		return PTR_ERR(clk);
431 
432 	pdata->clk = clk;
433 	clk_register_clkdev(clk, dev_desc->clk_con_id, devname);
434 	return 0;
435 }
436 
437 struct lpss_device_links {
438 	const char *supplier_hid;
439 	const char *supplier_uid;
440 	const char *consumer_hid;
441 	const char *consumer_uid;
442 	u32 flags;
443 };
444 
445 /*
446  * The _DEP method is used to identify dependencies but instead of creating
447  * device links for every handle in _DEP, only links in the following list are
448  * created. That is necessary because, in the general case, _DEP can refer to
449  * devices that might not have drivers, or that are on different buses, or where
450  * the supplier is not enumerated until after the consumer is probed.
451  */
452 static const struct lpss_device_links lpss_device_links[] = {
453 	{"808622C1", "7", "80860F14", "3", DL_FLAG_PM_RUNTIME},
454 };
455 
456 static bool hid_uid_match(const char *hid1, const char *uid1,
457 			  const char *hid2, const char *uid2)
458 {
459 	return !strcmp(hid1, hid2) && uid1 && uid2 && !strcmp(uid1, uid2);
460 }
461 
462 static bool acpi_lpss_is_supplier(struct acpi_device *adev,
463 				  const struct lpss_device_links *link)
464 {
465 	return hid_uid_match(acpi_device_hid(adev), acpi_device_uid(adev),
466 			     link->supplier_hid, link->supplier_uid);
467 }
468 
469 static bool acpi_lpss_is_consumer(struct acpi_device *adev,
470 				  const struct lpss_device_links *link)
471 {
472 	return hid_uid_match(acpi_device_hid(adev), acpi_device_uid(adev),
473 			     link->consumer_hid, link->consumer_uid);
474 }
475 
476 struct hid_uid {
477 	const char *hid;
478 	const char *uid;
479 };
480 
481 static int match_hid_uid(struct device *dev, void *data)
482 {
483 	struct acpi_device *adev = ACPI_COMPANION(dev);
484 	struct hid_uid *id = data;
485 
486 	if (!adev)
487 		return 0;
488 
489 	return hid_uid_match(acpi_device_hid(adev), acpi_device_uid(adev),
490 			     id->hid, id->uid);
491 }
492 
493 static struct device *acpi_lpss_find_device(const char *hid, const char *uid)
494 {
495 	struct hid_uid data = {
496 		.hid = hid,
497 		.uid = uid,
498 	};
499 
500 	return bus_find_device(&platform_bus_type, NULL, &data, match_hid_uid);
501 }
502 
503 static bool acpi_lpss_dep(struct acpi_device *adev, acpi_handle handle)
504 {
505 	struct acpi_handle_list dep_devices;
506 	acpi_status status;
507 	int i;
508 
509 	if (!acpi_has_method(adev->handle, "_DEP"))
510 		return false;
511 
512 	status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
513 					 &dep_devices);
514 	if (ACPI_FAILURE(status)) {
515 		dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
516 		return false;
517 	}
518 
519 	for (i = 0; i < dep_devices.count; i++) {
520 		if (dep_devices.handles[i] == handle)
521 			return true;
522 	}
523 
524 	return false;
525 }
526 
527 static void acpi_lpss_link_consumer(struct device *dev1,
528 				    const struct lpss_device_links *link)
529 {
530 	struct device *dev2;
531 
532 	dev2 = acpi_lpss_find_device(link->consumer_hid, link->consumer_uid);
533 	if (!dev2)
534 		return;
535 
536 	if (acpi_lpss_dep(ACPI_COMPANION(dev2), ACPI_HANDLE(dev1)))
537 		device_link_add(dev2, dev1, link->flags);
538 
539 	put_device(dev2);
540 }
541 
542 static void acpi_lpss_link_supplier(struct device *dev1,
543 				    const struct lpss_device_links *link)
544 {
545 	struct device *dev2;
546 
547 	dev2 = acpi_lpss_find_device(link->supplier_hid, link->supplier_uid);
548 	if (!dev2)
549 		return;
550 
551 	if (acpi_lpss_dep(ACPI_COMPANION(dev1), ACPI_HANDLE(dev2)))
552 		device_link_add(dev1, dev2, link->flags);
553 
554 	put_device(dev2);
555 }
556 
557 static void acpi_lpss_create_device_links(struct acpi_device *adev,
558 					  struct platform_device *pdev)
559 {
560 	int i;
561 
562 	for (i = 0; i < ARRAY_SIZE(lpss_device_links); i++) {
563 		const struct lpss_device_links *link = &lpss_device_links[i];
564 
565 		if (acpi_lpss_is_supplier(adev, link))
566 			acpi_lpss_link_consumer(&pdev->dev, link);
567 
568 		if (acpi_lpss_is_consumer(adev, link))
569 			acpi_lpss_link_supplier(&pdev->dev, link);
570 	}
571 }
572 
573 static int acpi_lpss_create_device(struct acpi_device *adev,
574 				   const struct acpi_device_id *id)
575 {
576 	const struct lpss_device_desc *dev_desc;
577 	struct lpss_private_data *pdata;
578 	struct resource_entry *rentry;
579 	struct list_head resource_list;
580 	struct platform_device *pdev;
581 	int ret;
582 
583 	dev_desc = (const struct lpss_device_desc *)id->driver_data;
584 	if (!dev_desc) {
585 		pdev = acpi_create_platform_device(adev, NULL);
586 		return IS_ERR_OR_NULL(pdev) ? PTR_ERR(pdev) : 1;
587 	}
588 	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
589 	if (!pdata)
590 		return -ENOMEM;
591 
592 	INIT_LIST_HEAD(&resource_list);
593 	ret = acpi_dev_get_resources(adev, &resource_list, is_memory, NULL);
594 	if (ret < 0)
595 		goto err_out;
596 
597 	list_for_each_entry(rentry, &resource_list, node)
598 		if (resource_type(rentry->res) == IORESOURCE_MEM) {
599 			if (dev_desc->prv_size_override)
600 				pdata->mmio_size = dev_desc->prv_size_override;
601 			else
602 				pdata->mmio_size = resource_size(rentry->res);
603 			pdata->mmio_base = ioremap(rentry->res->start,
604 						   pdata->mmio_size);
605 			break;
606 		}
607 
608 	acpi_dev_free_resource_list(&resource_list);
609 
610 	if (!pdata->mmio_base) {
611 		/* Avoid acpi_bus_attach() instantiating a pdev for this dev. */
612 		adev->pnp.type.platform_id = 0;
613 		/* Skip the device, but continue the namespace scan. */
614 		ret = 0;
615 		goto err_out;
616 	}
617 
618 	pdata->adev = adev;
619 	pdata->dev_desc = dev_desc;
620 
621 	if (dev_desc->setup)
622 		dev_desc->setup(pdata);
623 
624 	if (dev_desc->flags & LPSS_CLK) {
625 		ret = register_device_clock(adev, pdata);
626 		if (ret) {
627 			/* Skip the device, but continue the namespace scan. */
628 			ret = 0;
629 			goto err_out;
630 		}
631 	}
632 
633 	/*
634 	 * This works around a known issue in ACPI tables where LPSS devices
635 	 * have _PS0 and _PS3 without _PSC (and no power resources), so
636 	 * acpi_bus_init_power() will assume that the BIOS has put them into D0.
637 	 */
638 	ret = acpi_device_fix_up_power(adev);
639 	if (ret) {
640 		/* Skip the device, but continue the namespace scan. */
641 		ret = 0;
642 		goto err_out;
643 	}
644 
645 	adev->driver_data = pdata;
646 	pdev = acpi_create_platform_device(adev, dev_desc->properties);
647 	if (!IS_ERR_OR_NULL(pdev)) {
648 		acpi_lpss_create_device_links(adev, pdev);
649 		return 1;
650 	}
651 
652 	ret = PTR_ERR(pdev);
653 	adev->driver_data = NULL;
654 
655  err_out:
656 	kfree(pdata);
657 	return ret;
658 }
659 
660 static u32 __lpss_reg_read(struct lpss_private_data *pdata, unsigned int reg)
661 {
662 	return readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
663 }
664 
665 static void __lpss_reg_write(u32 val, struct lpss_private_data *pdata,
666 			     unsigned int reg)
667 {
668 	writel(val, pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
669 }
670 
671 static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val)
672 {
673 	struct acpi_device *adev;
674 	struct lpss_private_data *pdata;
675 	unsigned long flags;
676 	int ret;
677 
678 	ret = acpi_bus_get_device(ACPI_HANDLE(dev), &adev);
679 	if (WARN_ON(ret))
680 		return ret;
681 
682 	spin_lock_irqsave(&dev->power.lock, flags);
683 	if (pm_runtime_suspended(dev)) {
684 		ret = -EAGAIN;
685 		goto out;
686 	}
687 	pdata = acpi_driver_data(adev);
688 	if (WARN_ON(!pdata || !pdata->mmio_base)) {
689 		ret = -ENODEV;
690 		goto out;
691 	}
692 	*val = __lpss_reg_read(pdata, reg);
693 
694  out:
695 	spin_unlock_irqrestore(&dev->power.lock, flags);
696 	return ret;
697 }
698 
699 static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr,
700 			     char *buf)
701 {
702 	u32 ltr_value = 0;
703 	unsigned int reg;
704 	int ret;
705 
706 	reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR;
707 	ret = lpss_reg_read(dev, reg, &ltr_value);
708 	if (ret)
709 		return ret;
710 
711 	return snprintf(buf, PAGE_SIZE, "%08x\n", ltr_value);
712 }
713 
714 static ssize_t lpss_ltr_mode_show(struct device *dev,
715 				  struct device_attribute *attr, char *buf)
716 {
717 	u32 ltr_mode = 0;
718 	char *outstr;
719 	int ret;
720 
721 	ret = lpss_reg_read(dev, LPSS_GENERAL, &ltr_mode);
722 	if (ret)
723 		return ret;
724 
725 	outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto";
726 	return sprintf(buf, "%s\n", outstr);
727 }
728 
729 static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL);
730 static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL);
731 static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL);
732 
733 static struct attribute *lpss_attrs[] = {
734 	&dev_attr_auto_ltr.attr,
735 	&dev_attr_sw_ltr.attr,
736 	&dev_attr_ltr_mode.attr,
737 	NULL,
738 };
739 
740 static const struct attribute_group lpss_attr_group = {
741 	.attrs = lpss_attrs,
742 	.name = "lpss_ltr",
743 };
744 
745 static void acpi_lpss_set_ltr(struct device *dev, s32 val)
746 {
747 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
748 	u32 ltr_mode, ltr_val;
749 
750 	ltr_mode = __lpss_reg_read(pdata, LPSS_GENERAL);
751 	if (val < 0) {
752 		if (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) {
753 			ltr_mode &= ~LPSS_GENERAL_LTR_MODE_SW;
754 			__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
755 		}
756 		return;
757 	}
758 	ltr_val = __lpss_reg_read(pdata, LPSS_SW_LTR) & ~LPSS_LTR_SNOOP_MASK;
759 	if (val >= LPSS_LTR_SNOOP_LAT_CUTOFF) {
760 		ltr_val |= LPSS_LTR_SNOOP_LAT_32US;
761 		val = LPSS_LTR_MAX_VAL;
762 	} else if (val > LPSS_LTR_MAX_VAL) {
763 		ltr_val |= LPSS_LTR_SNOOP_LAT_32US | LPSS_LTR_SNOOP_REQ;
764 		val >>= LPSS_LTR_SNOOP_LAT_SHIFT;
765 	} else {
766 		ltr_val |= LPSS_LTR_SNOOP_LAT_1US | LPSS_LTR_SNOOP_REQ;
767 	}
768 	ltr_val |= val;
769 	__lpss_reg_write(ltr_val, pdata, LPSS_SW_LTR);
770 	if (!(ltr_mode & LPSS_GENERAL_LTR_MODE_SW)) {
771 		ltr_mode |= LPSS_GENERAL_LTR_MODE_SW;
772 		__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
773 	}
774 }
775 
776 #ifdef CONFIG_PM
777 /**
778  * acpi_lpss_save_ctx() - Save the private registers of LPSS device
779  * @dev: LPSS device
780  * @pdata: pointer to the private data of the LPSS device
781  *
782  * Most LPSS devices have private registers which may loose their context when
783  * the device is powered down. acpi_lpss_save_ctx() saves those registers into
784  * prv_reg_ctx array.
785  */
786 static void acpi_lpss_save_ctx(struct device *dev,
787 			       struct lpss_private_data *pdata)
788 {
789 	unsigned int i;
790 
791 	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
792 		unsigned long offset = i * sizeof(u32);
793 
794 		pdata->prv_reg_ctx[i] = __lpss_reg_read(pdata, offset);
795 		dev_dbg(dev, "saving 0x%08x from LPSS reg at offset 0x%02lx\n",
796 			pdata->prv_reg_ctx[i], offset);
797 	}
798 }
799 
800 /**
801  * acpi_lpss_restore_ctx() - Restore the private registers of LPSS device
802  * @dev: LPSS device
803  * @pdata: pointer to the private data of the LPSS device
804  *
805  * Restores the registers that were previously stored with acpi_lpss_save_ctx().
806  */
807 static void acpi_lpss_restore_ctx(struct device *dev,
808 				  struct lpss_private_data *pdata)
809 {
810 	unsigned int i;
811 
812 	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
813 		unsigned long offset = i * sizeof(u32);
814 
815 		__lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset);
816 		dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n",
817 			pdata->prv_reg_ctx[i], offset);
818 	}
819 }
820 
821 static void acpi_lpss_d3_to_d0_delay(struct lpss_private_data *pdata)
822 {
823 	/*
824 	 * The following delay is needed or the subsequent write operations may
825 	 * fail. The LPSS devices are actually PCI devices and the PCI spec
826 	 * expects 10ms delay before the device can be accessed after D3 to D0
827 	 * transition. However some platforms like BSW does not need this delay.
828 	 */
829 	unsigned int delay = 10;	/* default 10ms delay */
830 
831 	if (pdata->dev_desc->flags & LPSS_NO_D3_DELAY)
832 		delay = 0;
833 
834 	msleep(delay);
835 }
836 
837 static int acpi_lpss_activate(struct device *dev)
838 {
839 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
840 	int ret;
841 
842 	ret = acpi_dev_resume(dev);
843 	if (ret)
844 		return ret;
845 
846 	acpi_lpss_d3_to_d0_delay(pdata);
847 
848 	/*
849 	 * This is called only on ->probe() stage where a device is either in
850 	 * known state defined by BIOS or most likely powered off. Due to this
851 	 * we have to deassert reset line to be sure that ->probe() will
852 	 * recognize the device.
853 	 */
854 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
855 		lpss_deassert_reset(pdata);
856 
857 	return 0;
858 }
859 
860 static void acpi_lpss_dismiss(struct device *dev)
861 {
862 	acpi_dev_suspend(dev, false);
863 }
864 
865 /* IOSF SB for LPSS island */
866 #define LPSS_IOSF_UNIT_LPIOEP		0xA0
867 #define LPSS_IOSF_UNIT_LPIO1		0xAB
868 #define LPSS_IOSF_UNIT_LPIO2		0xAC
869 
870 #define LPSS_IOSF_PMCSR			0x84
871 #define LPSS_PMCSR_D0			0
872 #define LPSS_PMCSR_D3hot		3
873 #define LPSS_PMCSR_Dx_MASK		GENMASK(1, 0)
874 
875 #define LPSS_IOSF_GPIODEF0		0x154
876 #define LPSS_GPIODEF0_DMA1_D3		BIT(2)
877 #define LPSS_GPIODEF0_DMA2_D3		BIT(3)
878 #define LPSS_GPIODEF0_DMA_D3_MASK	GENMASK(3, 2)
879 #define LPSS_GPIODEF0_DMA_LLP		BIT(13)
880 
881 static DEFINE_MUTEX(lpss_iosf_mutex);
882 
883 static void lpss_iosf_enter_d3_state(void)
884 {
885 	u32 value1 = 0;
886 	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
887 	u32 value2 = LPSS_PMCSR_D3hot;
888 	u32 mask2 = LPSS_PMCSR_Dx_MASK;
889 	/*
890 	 * PMC provides an information about actual status of the LPSS devices.
891 	 * Here we read the values related to LPSS power island, i.e. LPSS
892 	 * devices, excluding both LPSS DMA controllers, along with SCC domain.
893 	 */
894 	u32 func_dis, d3_sts_0, pmc_status, pmc_mask = 0xfe000ffe;
895 	int ret;
896 
897 	ret = pmc_atom_read(PMC_FUNC_DIS, &func_dis);
898 	if (ret)
899 		return;
900 
901 	mutex_lock(&lpss_iosf_mutex);
902 
903 	ret = pmc_atom_read(PMC_D3_STS_0, &d3_sts_0);
904 	if (ret)
905 		goto exit;
906 
907 	/*
908 	 * Get the status of entire LPSS power island per device basis.
909 	 * Shutdown both LPSS DMA controllers if and only if all other devices
910 	 * are already in D3hot.
911 	 */
912 	pmc_status = (~(d3_sts_0 | func_dis)) & pmc_mask;
913 	if (pmc_status)
914 		goto exit;
915 
916 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
917 			LPSS_IOSF_PMCSR, value2, mask2);
918 
919 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
920 			LPSS_IOSF_PMCSR, value2, mask2);
921 
922 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
923 			LPSS_IOSF_GPIODEF0, value1, mask1);
924 exit:
925 	mutex_unlock(&lpss_iosf_mutex);
926 }
927 
928 static void lpss_iosf_exit_d3_state(void)
929 {
930 	u32 value1 = LPSS_GPIODEF0_DMA1_D3 | LPSS_GPIODEF0_DMA2_D3 |
931 		     LPSS_GPIODEF0_DMA_LLP;
932 	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
933 	u32 value2 = LPSS_PMCSR_D0;
934 	u32 mask2 = LPSS_PMCSR_Dx_MASK;
935 
936 	mutex_lock(&lpss_iosf_mutex);
937 
938 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
939 			LPSS_IOSF_GPIODEF0, value1, mask1);
940 
941 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
942 			LPSS_IOSF_PMCSR, value2, mask2);
943 
944 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
945 			LPSS_IOSF_PMCSR, value2, mask2);
946 
947 	mutex_unlock(&lpss_iosf_mutex);
948 }
949 
950 static int acpi_lpss_suspend(struct device *dev, bool runtime)
951 {
952 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
953 	bool wakeup = runtime || device_may_wakeup(dev);
954 	int ret;
955 
956 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
957 		acpi_lpss_save_ctx(dev, pdata);
958 
959 	ret = acpi_dev_suspend(dev, wakeup);
960 
961 	/*
962 	 * This call must be last in the sequence, otherwise PMC will return
963 	 * wrong status for devices being about to be powered off. See
964 	 * lpss_iosf_enter_d3_state() for further information.
965 	 */
966 	if ((runtime || !pm_suspend_via_firmware()) &&
967 	    lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
968 		lpss_iosf_enter_d3_state();
969 
970 	return ret;
971 }
972 
973 static int acpi_lpss_resume(struct device *dev, bool runtime)
974 {
975 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
976 	int ret;
977 
978 	/*
979 	 * This call is kept first to be in symmetry with
980 	 * acpi_lpss_runtime_suspend() one.
981 	 */
982 	if ((runtime || !pm_resume_via_firmware()) &&
983 	    lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
984 		lpss_iosf_exit_d3_state();
985 
986 	ret = acpi_dev_resume(dev);
987 	if (ret)
988 		return ret;
989 
990 	acpi_lpss_d3_to_d0_delay(pdata);
991 
992 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
993 		acpi_lpss_restore_ctx(dev, pdata);
994 
995 	return 0;
996 }
997 
998 #ifdef CONFIG_PM_SLEEP
999 static int acpi_lpss_suspend_late(struct device *dev)
1000 {
1001 	int ret;
1002 
1003 	if (dev_pm_smart_suspend_and_suspended(dev))
1004 		return 0;
1005 
1006 	ret = pm_generic_suspend_late(dev);
1007 	return ret ? ret : acpi_lpss_suspend(dev, false);
1008 }
1009 
1010 static int acpi_lpss_resume_early(struct device *dev)
1011 {
1012 	int ret = acpi_lpss_resume(dev, false);
1013 
1014 	return ret ? ret : pm_generic_resume_early(dev);
1015 }
1016 #endif /* CONFIG_PM_SLEEP */
1017 
1018 static int acpi_lpss_runtime_suspend(struct device *dev)
1019 {
1020 	int ret = pm_generic_runtime_suspend(dev);
1021 
1022 	return ret ? ret : acpi_lpss_suspend(dev, true);
1023 }
1024 
1025 static int acpi_lpss_runtime_resume(struct device *dev)
1026 {
1027 	int ret = acpi_lpss_resume(dev, true);
1028 
1029 	return ret ? ret : pm_generic_runtime_resume(dev);
1030 }
1031 #endif /* CONFIG_PM */
1032 
1033 static struct dev_pm_domain acpi_lpss_pm_domain = {
1034 #ifdef CONFIG_PM
1035 	.activate = acpi_lpss_activate,
1036 	.dismiss = acpi_lpss_dismiss,
1037 #endif
1038 	.ops = {
1039 #ifdef CONFIG_PM
1040 #ifdef CONFIG_PM_SLEEP
1041 		.prepare = acpi_subsys_prepare,
1042 		.complete = acpi_subsys_complete,
1043 		.suspend = acpi_subsys_suspend,
1044 		.suspend_late = acpi_lpss_suspend_late,
1045 		.suspend_noirq = acpi_subsys_suspend_noirq,
1046 		.resume_noirq = acpi_subsys_resume_noirq,
1047 		.resume_early = acpi_lpss_resume_early,
1048 		.freeze = acpi_subsys_freeze,
1049 		.freeze_late = acpi_subsys_freeze_late,
1050 		.freeze_noirq = acpi_subsys_freeze_noirq,
1051 		.thaw_noirq = acpi_subsys_thaw_noirq,
1052 		.poweroff = acpi_subsys_suspend,
1053 		.poweroff_late = acpi_lpss_suspend_late,
1054 		.poweroff_noirq = acpi_subsys_suspend_noirq,
1055 		.restore_noirq = acpi_subsys_resume_noirq,
1056 		.restore_early = acpi_lpss_resume_early,
1057 #endif
1058 		.runtime_suspend = acpi_lpss_runtime_suspend,
1059 		.runtime_resume = acpi_lpss_runtime_resume,
1060 #endif
1061 	},
1062 };
1063 
1064 static int acpi_lpss_platform_notify(struct notifier_block *nb,
1065 				     unsigned long action, void *data)
1066 {
1067 	struct platform_device *pdev = to_platform_device(data);
1068 	struct lpss_private_data *pdata;
1069 	struct acpi_device *adev;
1070 	const struct acpi_device_id *id;
1071 
1072 	id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev);
1073 	if (!id || !id->driver_data)
1074 		return 0;
1075 
1076 	if (acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev))
1077 		return 0;
1078 
1079 	pdata = acpi_driver_data(adev);
1080 	if (!pdata)
1081 		return 0;
1082 
1083 	if (pdata->mmio_base &&
1084 	    pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) {
1085 		dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n");
1086 		return 0;
1087 	}
1088 
1089 	switch (action) {
1090 	case BUS_NOTIFY_BIND_DRIVER:
1091 		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1092 		break;
1093 	case BUS_NOTIFY_DRIVER_NOT_BOUND:
1094 	case BUS_NOTIFY_UNBOUND_DRIVER:
1095 		dev_pm_domain_set(&pdev->dev, NULL);
1096 		break;
1097 	case BUS_NOTIFY_ADD_DEVICE:
1098 		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1099 		if (pdata->dev_desc->flags & LPSS_LTR)
1100 			return sysfs_create_group(&pdev->dev.kobj,
1101 						  &lpss_attr_group);
1102 		break;
1103 	case BUS_NOTIFY_DEL_DEVICE:
1104 		if (pdata->dev_desc->flags & LPSS_LTR)
1105 			sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group);
1106 		dev_pm_domain_set(&pdev->dev, NULL);
1107 		break;
1108 	default:
1109 		break;
1110 	}
1111 
1112 	return 0;
1113 }
1114 
1115 static struct notifier_block acpi_lpss_nb = {
1116 	.notifier_call = acpi_lpss_platform_notify,
1117 };
1118 
1119 static void acpi_lpss_bind(struct device *dev)
1120 {
1121 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1122 
1123 	if (!pdata || !pdata->mmio_base || !(pdata->dev_desc->flags & LPSS_LTR))
1124 		return;
1125 
1126 	if (pdata->mmio_size >= pdata->dev_desc->prv_offset + LPSS_LTR_SIZE)
1127 		dev->power.set_latency_tolerance = acpi_lpss_set_ltr;
1128 	else
1129 		dev_err(dev, "MMIO size insufficient to access LTR\n");
1130 }
1131 
1132 static void acpi_lpss_unbind(struct device *dev)
1133 {
1134 	dev->power.set_latency_tolerance = NULL;
1135 }
1136 
1137 static struct acpi_scan_handler lpss_handler = {
1138 	.ids = acpi_lpss_device_ids,
1139 	.attach = acpi_lpss_create_device,
1140 	.bind = acpi_lpss_bind,
1141 	.unbind = acpi_lpss_unbind,
1142 };
1143 
1144 void __init acpi_lpss_init(void)
1145 {
1146 	const struct x86_cpu_id *id;
1147 	int ret;
1148 
1149 	ret = lpt_clk_init();
1150 	if (ret)
1151 		return;
1152 
1153 	id = x86_match_cpu(lpss_cpu_ids);
1154 	if (id)
1155 		lpss_quirks |= LPSS_QUIRK_ALWAYS_POWER_ON;
1156 
1157 	bus_register_notifier(&platform_bus_type, &acpi_lpss_nb);
1158 	acpi_scan_add_handler(&lpss_handler);
1159 }
1160 
1161 #else
1162 
1163 static struct acpi_scan_handler lpss_handler = {
1164 	.ids = acpi_lpss_device_ids,
1165 };
1166 
1167 void __init acpi_lpss_init(void)
1168 {
1169 	acpi_scan_add_handler(&lpss_handler);
1170 }
1171 
1172 #endif /* CONFIG_X86_INTEL_LPSS */
1173