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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/pm_domain.h>
22#include <linux/pm_runtime.h>
23#include <linux/delay.h>
24
25#include "internal.h"
26
27ACPI_MODULE_NAME("acpi_lpss");
28
29#ifdef CONFIG_X86_INTEL_LPSS
30
31#include <asm/cpu_device_id.h>
32#include <asm/iosf_mbi.h>
33#include <asm/pmc_atom.h>
34
35#define LPSS_ADDR(desc) ((unsigned long)&desc)
36
37#define LPSS_CLK_SIZE 0x04
38#define LPSS_LTR_SIZE 0x18
39
40/* Offsets relative to LPSS_PRIVATE_OFFSET */
41#define LPSS_CLK_DIVIDER_DEF_MASK (BIT(1) | BIT(16))
42#define LPSS_RESETS 0x04
43#define LPSS_RESETS_RESET_FUNC BIT(0)
44#define LPSS_RESETS_RESET_APB BIT(1)
45#define LPSS_GENERAL 0x08
46#define LPSS_GENERAL_LTR_MODE_SW BIT(2)
47#define LPSS_GENERAL_UART_RTS_OVRD BIT(3)
48#define LPSS_SW_LTR 0x10
49#define LPSS_AUTO_LTR 0x14
50#define LPSS_LTR_SNOOP_REQ BIT(15)
51#define LPSS_LTR_SNOOP_MASK 0x0000FFFF
52#define LPSS_LTR_SNOOP_LAT_1US 0x800
53#define LPSS_LTR_SNOOP_LAT_32US 0xC00
54#define LPSS_LTR_SNOOP_LAT_SHIFT 5
55#define LPSS_LTR_SNOOP_LAT_CUTOFF 3000
56#define LPSS_LTR_MAX_VAL 0x3FF
57#define LPSS_TX_INT 0x20
58#define LPSS_TX_INT_MASK BIT(1)
59
60#define LPSS_PRV_REG_COUNT 9
61
62/* LPSS Flags */
63#define LPSS_CLK BIT(0)
64#define LPSS_CLK_GATE BIT(1)
65#define LPSS_CLK_DIVIDER BIT(2)
66#define LPSS_LTR BIT(3)
67#define LPSS_SAVE_CTX BIT(4)
68#define LPSS_NO_D3_DELAY BIT(5)
69
70struct lpss_private_data;
71
72struct lpss_device_desc {
73 unsigned int flags;
74 const char *clk_con_id;
75 unsigned int prv_offset;
76 size_t prv_size_override;
77 void (*setup)(struct lpss_private_data *pdata);
78};
79
80static const struct lpss_device_desc lpss_dma_desc = {
81 .flags = LPSS_CLK,
82};
83
84struct lpss_private_data {
85 void __iomem *mmio_base;
86 resource_size_t mmio_size;
87 unsigned int fixed_clk_rate;
88 struct clk *clk;
89 const struct lpss_device_desc *dev_desc;
90 u32 prv_reg_ctx[LPSS_PRV_REG_COUNT];
91};
92
93/* LPSS run time quirks */
94static unsigned int lpss_quirks;
95
96/*
97 * LPSS_QUIRK_ALWAYS_POWER_ON: override power state for LPSS DMA device.
98 *
99 * The LPSS DMA controller has neither _PS0 nor _PS3 method. Moreover
100 * it can be powered off automatically whenever the last LPSS device goes down.
101 * In case of no power any access to the DMA controller will hang the system.
102 * The behaviour is reproduced on some HP laptops based on Intel BayTrail as
103 * well as on ASuS T100TA transformer.
104 *
105 * This quirk overrides power state of entire LPSS island to keep DMA powered
106 * on whenever we have at least one other device in use.
107 */
108#define LPSS_QUIRK_ALWAYS_POWER_ON BIT(0)
109
110/* UART Component Parameter Register */
111#define LPSS_UART_CPR 0xF4
112#define LPSS_UART_CPR_AFCE BIT(4)
113
114static void lpss_uart_setup(struct lpss_private_data *pdata)
115{
116 unsigned int offset;
117 u32 val;
118
119 offset = pdata->dev_desc->prv_offset + LPSS_TX_INT;
120 val = readl(pdata->mmio_base + offset);
121 writel(val | LPSS_TX_INT_MASK, pdata->mmio_base + offset);
122
123 val = readl(pdata->mmio_base + LPSS_UART_CPR);
124 if (!(val & LPSS_UART_CPR_AFCE)) {
125 offset = pdata->dev_desc->prv_offset + LPSS_GENERAL;
126 val = readl(pdata->mmio_base + offset);
127 val |= LPSS_GENERAL_UART_RTS_OVRD;
128 writel(val, pdata->mmio_base + offset);
129 }
130}
131
132static void lpss_deassert_reset(struct lpss_private_data *pdata)
133{
134 unsigned int offset;
135 u32 val;
136
137 offset = pdata->dev_desc->prv_offset + LPSS_RESETS;
138 val = readl(pdata->mmio_base + offset);
139 val |= LPSS_RESETS_RESET_APB | LPSS_RESETS_RESET_FUNC;
140 writel(val, pdata->mmio_base + offset);
141}
142
143#define LPSS_I2C_ENABLE 0x6c
144
145static void byt_i2c_setup(struct lpss_private_data *pdata)
146{
147 lpss_deassert_reset(pdata);
148
149 if (readl(pdata->mmio_base + pdata->dev_desc->prv_offset))
150 pdata->fixed_clk_rate = 133000000;
151
152 writel(0, pdata->mmio_base + LPSS_I2C_ENABLE);
153}
154
155static const struct lpss_device_desc lpt_dev_desc = {
156 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR,
157 .prv_offset = 0x800,
158};
159
160static const struct lpss_device_desc lpt_i2c_dev_desc = {
161 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_LTR,
162 .prv_offset = 0x800,
163};
164
165static const struct lpss_device_desc lpt_uart_dev_desc = {
166 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR,
167 .clk_con_id = "baudclk",
168 .prv_offset = 0x800,
169 .setup = lpss_uart_setup,
170};
171
172static const struct lpss_device_desc lpt_sdio_dev_desc = {
173 .flags = LPSS_LTR,
174 .prv_offset = 0x1000,
175 .prv_size_override = 0x1018,
176};
177
178static const struct lpss_device_desc byt_pwm_dev_desc = {
179 .flags = LPSS_SAVE_CTX,
180};
181
182static const struct lpss_device_desc bsw_pwm_dev_desc = {
183 .flags = LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
184};
185
186static const struct lpss_device_desc byt_uart_dev_desc = {
187 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
188 .clk_con_id = "baudclk",
189 .prv_offset = 0x800,
190 .setup = lpss_uart_setup,
191};
192
193static const struct lpss_device_desc bsw_uart_dev_desc = {
194 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
195 | LPSS_NO_D3_DELAY,
196 .clk_con_id = "baudclk",
197 .prv_offset = 0x800,
198 .setup = lpss_uart_setup,
199};
200
201static const struct lpss_device_desc byt_spi_dev_desc = {
202 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
203 .prv_offset = 0x400,
204};
205
206static const struct lpss_device_desc byt_sdio_dev_desc = {
207 .flags = LPSS_CLK,
208};
209
210static const struct lpss_device_desc byt_i2c_dev_desc = {
211 .flags = LPSS_CLK | LPSS_SAVE_CTX,
212 .prv_offset = 0x800,
213 .setup = byt_i2c_setup,
214};
215
216static const struct lpss_device_desc bsw_i2c_dev_desc = {
217 .flags = LPSS_CLK | LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
218 .prv_offset = 0x800,
219 .setup = byt_i2c_setup,
220};
221
222static const struct lpss_device_desc bsw_spi_dev_desc = {
223 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
224 | LPSS_NO_D3_DELAY,
225 .prv_offset = 0x400,
226 .setup = lpss_deassert_reset,
227};
228
229#define ICPU(model) { X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, }
230
231static const struct x86_cpu_id lpss_cpu_ids[] = {
232 ICPU(0x37), /* Valleyview, Bay Trail */
233 ICPU(0x4c), /* Braswell, Cherry Trail */
234 {}
235};
236
237#else
238
239#define LPSS_ADDR(desc) (0UL)
240
241#endif /* CONFIG_X86_INTEL_LPSS */
242
243static const struct acpi_device_id acpi_lpss_device_ids[] = {
244 /* Generic LPSS devices */
245 { "INTL9C60", LPSS_ADDR(lpss_dma_desc) },
246
247 /* Lynxpoint LPSS devices */
248 { "INT33C0", LPSS_ADDR(lpt_dev_desc) },
249 { "INT33C1", LPSS_ADDR(lpt_dev_desc) },
250 { "INT33C2", LPSS_ADDR(lpt_i2c_dev_desc) },
251 { "INT33C3", LPSS_ADDR(lpt_i2c_dev_desc) },
252 { "INT33C4", LPSS_ADDR(lpt_uart_dev_desc) },
253 { "INT33C5", LPSS_ADDR(lpt_uart_dev_desc) },
254 { "INT33C6", LPSS_ADDR(lpt_sdio_dev_desc) },
255 { "INT33C7", },
256
257 /* BayTrail LPSS devices */
258 { "80860F09", LPSS_ADDR(byt_pwm_dev_desc) },
259 { "80860F0A", LPSS_ADDR(byt_uart_dev_desc) },
260 { "80860F0E", LPSS_ADDR(byt_spi_dev_desc) },
261 { "80860F14", LPSS_ADDR(byt_sdio_dev_desc) },
262 { "80860F41", LPSS_ADDR(byt_i2c_dev_desc) },
263 { "INT33B2", },
264 { "INT33FC", },
265
266 /* Braswell LPSS devices */
267 { "80862288", LPSS_ADDR(bsw_pwm_dev_desc) },
268 { "8086228A", LPSS_ADDR(bsw_uart_dev_desc) },
269 { "8086228E", LPSS_ADDR(bsw_spi_dev_desc) },
270 { "808622C1", LPSS_ADDR(bsw_i2c_dev_desc) },
271
272 /* Broadwell LPSS devices */
273 { "INT3430", LPSS_ADDR(lpt_dev_desc) },
274 { "INT3431", LPSS_ADDR(lpt_dev_desc) },
275 { "INT3432", LPSS_ADDR(lpt_i2c_dev_desc) },
276 { "INT3433", LPSS_ADDR(lpt_i2c_dev_desc) },
277 { "INT3434", LPSS_ADDR(lpt_uart_dev_desc) },
278 { "INT3435", LPSS_ADDR(lpt_uart_dev_desc) },
279 { "INT3436", LPSS_ADDR(lpt_sdio_dev_desc) },
280 { "INT3437", },
281
282 /* Wildcat Point LPSS devices */
283 { "INT3438", LPSS_ADDR(lpt_dev_desc) },
284
285 { }
286};
287
288#ifdef CONFIG_X86_INTEL_LPSS
289
290static int is_memory(struct acpi_resource *res, void *not_used)
291{
292 struct resource r;
293 return !acpi_dev_resource_memory(res, &r);
294}
295
296/* LPSS main clock device. */
297static struct platform_device *lpss_clk_dev;
298
299static inline void lpt_register_clock_device(void)
300{
301 lpss_clk_dev = platform_device_register_simple("clk-lpt", -1, NULL, 0);
302}
303
304static int register_device_clock(struct acpi_device *adev,
305 struct lpss_private_data *pdata)
306{
307 const struct lpss_device_desc *dev_desc = pdata->dev_desc;
308 const char *devname = dev_name(&adev->dev);
309 struct clk *clk = ERR_PTR(-ENODEV);
310 struct lpss_clk_data *clk_data;
311 const char *parent, *clk_name;
312 void __iomem *prv_base;
313
314 if (!lpss_clk_dev)
315 lpt_register_clock_device();
316
317 clk_data = platform_get_drvdata(lpss_clk_dev);
318 if (!clk_data)
319 return -ENODEV;
320 clk = clk_data->clk;
321
322 if (!pdata->mmio_base
323 || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE)
324 return -ENODATA;
325
326 parent = clk_data->name;
327 prv_base = pdata->mmio_base + dev_desc->prv_offset;
328
329 if (pdata->fixed_clk_rate) {
330 clk = clk_register_fixed_rate(NULL, devname, parent, 0,
331 pdata->fixed_clk_rate);
332 goto out;
333 }
334
335 if (dev_desc->flags & LPSS_CLK_GATE) {
336 clk = clk_register_gate(NULL, devname, parent, 0,
337 prv_base, 0, 0, NULL);
338 parent = devname;
339 }
340
341 if (dev_desc->flags & LPSS_CLK_DIVIDER) {
342 /* Prevent division by zero */
343 if (!readl(prv_base))
344 writel(LPSS_CLK_DIVIDER_DEF_MASK, prv_base);
345
346 clk_name = kasprintf(GFP_KERNEL, "%s-div", devname);
347 if (!clk_name)
348 return -ENOMEM;
349 clk = clk_register_fractional_divider(NULL, clk_name, parent,
350 0, prv_base,
351 1, 15, 16, 15, 0, NULL);
352 parent = clk_name;
353
354 clk_name = kasprintf(GFP_KERNEL, "%s-update", devname);
355 if (!clk_name) {
356 kfree(parent);
357 return -ENOMEM;
358 }
359 clk = clk_register_gate(NULL, clk_name, parent,
360 CLK_SET_RATE_PARENT | CLK_SET_RATE_GATE,
361 prv_base, 31, 0, NULL);
362 kfree(parent);
363 kfree(clk_name);
364 }
365out:
366 if (IS_ERR(clk))
367 return PTR_ERR(clk);
368
369 pdata->clk = clk;
370 clk_register_clkdev(clk, dev_desc->clk_con_id, devname);
371 return 0;
372}
373
374static int acpi_lpss_create_device(struct acpi_device *adev,
375 const struct acpi_device_id *id)
376{
377 const struct lpss_device_desc *dev_desc;
378 struct lpss_private_data *pdata;
379 struct resource_entry *rentry;
380 struct list_head resource_list;
381 struct platform_device *pdev;
382 int ret;
383
384 dev_desc = (const struct lpss_device_desc *)id->driver_data;
385 if (!dev_desc) {
386 pdev = acpi_create_platform_device(adev);
387 return IS_ERR_OR_NULL(pdev) ? PTR_ERR(pdev) : 1;
388 }
389 pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
390 if (!pdata)
391 return -ENOMEM;
392
393 INIT_LIST_HEAD(&resource_list);
394 ret = acpi_dev_get_resources(adev, &resource_list, is_memory, NULL);
395 if (ret < 0)
396 goto err_out;
397
398 list_for_each_entry(rentry, &resource_list, node)
399 if (resource_type(rentry->res) == IORESOURCE_MEM) {
400 if (dev_desc->prv_size_override)
401 pdata->mmio_size = dev_desc->prv_size_override;
402 else
403 pdata->mmio_size = resource_size(rentry->res);
404 pdata->mmio_base = ioremap(rentry->res->start,
405 pdata->mmio_size);
406 break;
407 }
408
409 acpi_dev_free_resource_list(&resource_list);
410
411 if (!pdata->mmio_base) {
412 ret = -ENOMEM;
413 goto err_out;
414 }
415
416 pdata->dev_desc = dev_desc;
417
418 if (dev_desc->setup)
419 dev_desc->setup(pdata);
420
421 if (dev_desc->flags & LPSS_CLK) {
422 ret = register_device_clock(adev, pdata);
423 if (ret) {
424 /* Skip the device, but continue the namespace scan. */
425 ret = 0;
426 goto err_out;
427 }
428 }
429
430 /*
431 * This works around a known issue in ACPI tables where LPSS devices
432 * have _PS0 and _PS3 without _PSC (and no power resources), so
433 * acpi_bus_init_power() will assume that the BIOS has put them into D0.
434 */
435 ret = acpi_device_fix_up_power(adev);
436 if (ret) {
437 /* Skip the device, but continue the namespace scan. */
438 ret = 0;
439 goto err_out;
440 }
441
442 adev->driver_data = pdata;
443 pdev = acpi_create_platform_device(adev);
444 if (!IS_ERR_OR_NULL(pdev)) {
445 return 1;
446 }
447
448 ret = PTR_ERR(pdev);
449 adev->driver_data = NULL;
450
451 err_out:
452 kfree(pdata);
453 return ret;
454}
455
456static u32 __lpss_reg_read(struct lpss_private_data *pdata, unsigned int reg)
457{
458 return readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
459}
460
461static void __lpss_reg_write(u32 val, struct lpss_private_data *pdata,
462 unsigned int reg)
463{
464 writel(val, pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
465}
466
467static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val)
468{
469 struct acpi_device *adev;
470 struct lpss_private_data *pdata;
471 unsigned long flags;
472 int ret;
473
474 ret = acpi_bus_get_device(ACPI_HANDLE(dev), &adev);
475 if (WARN_ON(ret))
476 return ret;
477
478 spin_lock_irqsave(&dev->power.lock, flags);
479 if (pm_runtime_suspended(dev)) {
480 ret = -EAGAIN;
481 goto out;
482 }
483 pdata = acpi_driver_data(adev);
484 if (WARN_ON(!pdata || !pdata->mmio_base)) {
485 ret = -ENODEV;
486 goto out;
487 }
488 *val = __lpss_reg_read(pdata, reg);
489
490 out:
491 spin_unlock_irqrestore(&dev->power.lock, flags);
492 return ret;
493}
494
495static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr,
496 char *buf)
497{
498 u32 ltr_value = 0;
499 unsigned int reg;
500 int ret;
501
502 reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR;
503 ret = lpss_reg_read(dev, reg, <r_value);
504 if (ret)
505 return ret;
506
507 return snprintf(buf, PAGE_SIZE, "%08x\n", ltr_value);
508}
509
510static ssize_t lpss_ltr_mode_show(struct device *dev,
511 struct device_attribute *attr, char *buf)
512{
513 u32 ltr_mode = 0;
514 char *outstr;
515 int ret;
516
517 ret = lpss_reg_read(dev, LPSS_GENERAL, <r_mode);
518 if (ret)
519 return ret;
520
521 outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto";
522 return sprintf(buf, "%s\n", outstr);
523}
524
525static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL);
526static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL);
527static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL);
528
529static struct attribute *lpss_attrs[] = {
530 &dev_attr_auto_ltr.attr,
531 &dev_attr_sw_ltr.attr,
532 &dev_attr_ltr_mode.attr,
533 NULL,
534};
535
536static struct attribute_group lpss_attr_group = {
537 .attrs = lpss_attrs,
538 .name = "lpss_ltr",
539};
540
541static void acpi_lpss_set_ltr(struct device *dev, s32 val)
542{
543 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
544 u32 ltr_mode, ltr_val;
545
546 ltr_mode = __lpss_reg_read(pdata, LPSS_GENERAL);
547 if (val < 0) {
548 if (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) {
549 ltr_mode &= ~LPSS_GENERAL_LTR_MODE_SW;
550 __lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
551 }
552 return;
553 }
554 ltr_val = __lpss_reg_read(pdata, LPSS_SW_LTR) & ~LPSS_LTR_SNOOP_MASK;
555 if (val >= LPSS_LTR_SNOOP_LAT_CUTOFF) {
556 ltr_val |= LPSS_LTR_SNOOP_LAT_32US;
557 val = LPSS_LTR_MAX_VAL;
558 } else if (val > LPSS_LTR_MAX_VAL) {
559 ltr_val |= LPSS_LTR_SNOOP_LAT_32US | LPSS_LTR_SNOOP_REQ;
560 val >>= LPSS_LTR_SNOOP_LAT_SHIFT;
561 } else {
562 ltr_val |= LPSS_LTR_SNOOP_LAT_1US | LPSS_LTR_SNOOP_REQ;
563 }
564 ltr_val |= val;
565 __lpss_reg_write(ltr_val, pdata, LPSS_SW_LTR);
566 if (!(ltr_mode & LPSS_GENERAL_LTR_MODE_SW)) {
567 ltr_mode |= LPSS_GENERAL_LTR_MODE_SW;
568 __lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
569 }
570}
571
572#ifdef CONFIG_PM
573/**
574 * acpi_lpss_save_ctx() - Save the private registers of LPSS device
575 * @dev: LPSS device
576 * @pdata: pointer to the private data of the LPSS device
577 *
578 * Most LPSS devices have private registers which may loose their context when
579 * the device is powered down. acpi_lpss_save_ctx() saves those registers into
580 * prv_reg_ctx array.
581 */
582static void acpi_lpss_save_ctx(struct device *dev,
583 struct lpss_private_data *pdata)
584{
585 unsigned int i;
586
587 for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
588 unsigned long offset = i * sizeof(u32);
589
590 pdata->prv_reg_ctx[i] = __lpss_reg_read(pdata, offset);
591 dev_dbg(dev, "saving 0x%08x from LPSS reg at offset 0x%02lx\n",
592 pdata->prv_reg_ctx[i], offset);
593 }
594}
595
596/**
597 * acpi_lpss_restore_ctx() - Restore the private registers of LPSS device
598 * @dev: LPSS device
599 * @pdata: pointer to the private data of the LPSS device
600 *
601 * Restores the registers that were previously stored with acpi_lpss_save_ctx().
602 */
603static void acpi_lpss_restore_ctx(struct device *dev,
604 struct lpss_private_data *pdata)
605{
606 unsigned int i;
607
608 for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
609 unsigned long offset = i * sizeof(u32);
610
611 __lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset);
612 dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n",
613 pdata->prv_reg_ctx[i], offset);
614 }
615}
616
617static void acpi_lpss_d3_to_d0_delay(struct lpss_private_data *pdata)
618{
619 /*
620 * The following delay is needed or the subsequent write operations may
621 * fail. The LPSS devices are actually PCI devices and the PCI spec
622 * expects 10ms delay before the device can be accessed after D3 to D0
623 * transition. However some platforms like BSW does not need this delay.
624 */
625 unsigned int delay = 10; /* default 10ms delay */
626
627 if (pdata->dev_desc->flags & LPSS_NO_D3_DELAY)
628 delay = 0;
629
630 msleep(delay);
631}
632
633static int acpi_lpss_activate(struct device *dev)
634{
635 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
636 int ret;
637
638 ret = acpi_dev_runtime_resume(dev);
639 if (ret)
640 return ret;
641
642 acpi_lpss_d3_to_d0_delay(pdata);
643
644 /*
645 * This is called only on ->probe() stage where a device is either in
646 * known state defined by BIOS or most likely powered off. Due to this
647 * we have to deassert reset line to be sure that ->probe() will
648 * recognize the device.
649 */
650 if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
651 lpss_deassert_reset(pdata);
652
653 return 0;
654}
655
656static void acpi_lpss_dismiss(struct device *dev)
657{
658 acpi_dev_runtime_suspend(dev);
659}
660
661#ifdef CONFIG_PM_SLEEP
662static int acpi_lpss_suspend_late(struct device *dev)
663{
664 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
665 int ret;
666
667 ret = pm_generic_suspend_late(dev);
668 if (ret)
669 return ret;
670
671 if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
672 acpi_lpss_save_ctx(dev, pdata);
673
674 return acpi_dev_suspend_late(dev);
675}
676
677static int acpi_lpss_resume_early(struct device *dev)
678{
679 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
680 int ret;
681
682 ret = acpi_dev_resume_early(dev);
683 if (ret)
684 return ret;
685
686 acpi_lpss_d3_to_d0_delay(pdata);
687
688 if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
689 acpi_lpss_restore_ctx(dev, pdata);
690
691 return pm_generic_resume_early(dev);
692}
693#endif /* CONFIG_PM_SLEEP */
694
695/* IOSF SB for LPSS island */
696#define LPSS_IOSF_UNIT_LPIOEP 0xA0
697#define LPSS_IOSF_UNIT_LPIO1 0xAB
698#define LPSS_IOSF_UNIT_LPIO2 0xAC
699
700#define LPSS_IOSF_PMCSR 0x84
701#define LPSS_PMCSR_D0 0
702#define LPSS_PMCSR_D3hot 3
703#define LPSS_PMCSR_Dx_MASK GENMASK(1, 0)
704
705#define LPSS_IOSF_GPIODEF0 0x154
706#define LPSS_GPIODEF0_DMA1_D3 BIT(2)
707#define LPSS_GPIODEF0_DMA2_D3 BIT(3)
708#define LPSS_GPIODEF0_DMA_D3_MASK GENMASK(3, 2)
709
710static DEFINE_MUTEX(lpss_iosf_mutex);
711
712static void lpss_iosf_enter_d3_state(void)
713{
714 u32 value1 = 0;
715 u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK;
716 u32 value2 = LPSS_PMCSR_D3hot;
717 u32 mask2 = LPSS_PMCSR_Dx_MASK;
718 /*
719 * PMC provides an information about actual status of the LPSS devices.
720 * Here we read the values related to LPSS power island, i.e. LPSS
721 * devices, excluding both LPSS DMA controllers, along with SCC domain.
722 */
723 u32 func_dis, d3_sts_0, pmc_status, pmc_mask = 0xfe000ffe;
724 int ret;
725
726 ret = pmc_atom_read(PMC_FUNC_DIS, &func_dis);
727 if (ret)
728 return;
729
730 mutex_lock(&lpss_iosf_mutex);
731
732 ret = pmc_atom_read(PMC_D3_STS_0, &d3_sts_0);
733 if (ret)
734 goto exit;
735
736 /*
737 * Get the status of entire LPSS power island per device basis.
738 * Shutdown both LPSS DMA controllers if and only if all other devices
739 * are already in D3hot.
740 */
741 pmc_status = (~(d3_sts_0 | func_dis)) & pmc_mask;
742 if (pmc_status)
743 goto exit;
744
745 iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
746 LPSS_IOSF_PMCSR, value2, mask2);
747
748 iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
749 LPSS_IOSF_PMCSR, value2, mask2);
750
751 iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
752 LPSS_IOSF_GPIODEF0, value1, mask1);
753exit:
754 mutex_unlock(&lpss_iosf_mutex);
755}
756
757static void lpss_iosf_exit_d3_state(void)
758{
759 u32 value1 = LPSS_GPIODEF0_DMA1_D3 | LPSS_GPIODEF0_DMA2_D3;
760 u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK;
761 u32 value2 = LPSS_PMCSR_D0;
762 u32 mask2 = LPSS_PMCSR_Dx_MASK;
763
764 mutex_lock(&lpss_iosf_mutex);
765
766 iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
767 LPSS_IOSF_GPIODEF0, value1, mask1);
768
769 iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
770 LPSS_IOSF_PMCSR, value2, mask2);
771
772 iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
773 LPSS_IOSF_PMCSR, value2, mask2);
774
775 mutex_unlock(&lpss_iosf_mutex);
776}
777
778static int acpi_lpss_runtime_suspend(struct device *dev)
779{
780 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
781 int ret;
782
783 ret = pm_generic_runtime_suspend(dev);
784 if (ret)
785 return ret;
786
787 if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
788 acpi_lpss_save_ctx(dev, pdata);
789
790 ret = acpi_dev_runtime_suspend(dev);
791
792 /*
793 * This call must be last in the sequence, otherwise PMC will return
794 * wrong status for devices being about to be powered off. See
795 * lpss_iosf_enter_d3_state() for further information.
796 */
797 if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
798 lpss_iosf_enter_d3_state();
799
800 return ret;
801}
802
803static int acpi_lpss_runtime_resume(struct device *dev)
804{
805 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
806 int ret;
807
808 /*
809 * This call is kept first to be in symmetry with
810 * acpi_lpss_runtime_suspend() one.
811 */
812 if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
813 lpss_iosf_exit_d3_state();
814
815 ret = acpi_dev_runtime_resume(dev);
816 if (ret)
817 return ret;
818
819 acpi_lpss_d3_to_d0_delay(pdata);
820
821 if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
822 acpi_lpss_restore_ctx(dev, pdata);
823
824 return pm_generic_runtime_resume(dev);
825}
826#endif /* CONFIG_PM */
827
828static struct dev_pm_domain acpi_lpss_pm_domain = {
829#ifdef CONFIG_PM
830 .activate = acpi_lpss_activate,
831 .dismiss = acpi_lpss_dismiss,
832#endif
833 .ops = {
834#ifdef CONFIG_PM
835#ifdef CONFIG_PM_SLEEP
836 .prepare = acpi_subsys_prepare,
837 .complete = pm_complete_with_resume_check,
838 .suspend = acpi_subsys_suspend,
839 .suspend_late = acpi_lpss_suspend_late,
840 .resume_early = acpi_lpss_resume_early,
841 .freeze = acpi_subsys_freeze,
842 .poweroff = acpi_subsys_suspend,
843 .poweroff_late = acpi_lpss_suspend_late,
844 .restore_early = acpi_lpss_resume_early,
845#endif
846 .runtime_suspend = acpi_lpss_runtime_suspend,
847 .runtime_resume = acpi_lpss_runtime_resume,
848#endif
849 },
850};
851
852static int acpi_lpss_platform_notify(struct notifier_block *nb,
853 unsigned long action, void *data)
854{
855 struct platform_device *pdev = to_platform_device(data);
856 struct lpss_private_data *pdata;
857 struct acpi_device *adev;
858 const struct acpi_device_id *id;
859
860 id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev);
861 if (!id || !id->driver_data)
862 return 0;
863
864 if (acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev))
865 return 0;
866
867 pdata = acpi_driver_data(adev);
868 if (!pdata)
869 return 0;
870
871 if (pdata->mmio_base &&
872 pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) {
873 dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n");
874 return 0;
875 }
876
877 switch (action) {
878 case BUS_NOTIFY_BIND_DRIVER:
879 dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
880 break;
881 case BUS_NOTIFY_DRIVER_NOT_BOUND:
882 case BUS_NOTIFY_UNBOUND_DRIVER:
883 dev_pm_domain_set(&pdev->dev, NULL);
884 break;
885 case BUS_NOTIFY_ADD_DEVICE:
886 dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
887 if (pdata->dev_desc->flags & LPSS_LTR)
888 return sysfs_create_group(&pdev->dev.kobj,
889 &lpss_attr_group);
890 break;
891 case BUS_NOTIFY_DEL_DEVICE:
892 if (pdata->dev_desc->flags & LPSS_LTR)
893 sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group);
894 dev_pm_domain_set(&pdev->dev, NULL);
895 break;
896 default:
897 break;
898 }
899
900 return 0;
901}
902
903static struct notifier_block acpi_lpss_nb = {
904 .notifier_call = acpi_lpss_platform_notify,
905};
906
907static void acpi_lpss_bind(struct device *dev)
908{
909 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
910
911 if (!pdata || !pdata->mmio_base || !(pdata->dev_desc->flags & LPSS_LTR))
912 return;
913
914 if (pdata->mmio_size >= pdata->dev_desc->prv_offset + LPSS_LTR_SIZE)
915 dev->power.set_latency_tolerance = acpi_lpss_set_ltr;
916 else
917 dev_err(dev, "MMIO size insufficient to access LTR\n");
918}
919
920static void acpi_lpss_unbind(struct device *dev)
921{
922 dev->power.set_latency_tolerance = NULL;
923}
924
925static struct acpi_scan_handler lpss_handler = {
926 .ids = acpi_lpss_device_ids,
927 .attach = acpi_lpss_create_device,
928 .bind = acpi_lpss_bind,
929 .unbind = acpi_lpss_unbind,
930};
931
932void __init acpi_lpss_init(void)
933{
934 const struct x86_cpu_id *id;
935 int ret;
936
937 ret = lpt_clk_init();
938 if (ret)
939 return;
940
941 id = x86_match_cpu(lpss_cpu_ids);
942 if (id)
943 lpss_quirks |= LPSS_QUIRK_ALWAYS_POWER_ON;
944
945 bus_register_notifier(&platform_bus_type, &acpi_lpss_nb);
946 acpi_scan_add_handler(&lpss_handler);
947}
948
949#else
950
951static struct acpi_scan_handler lpss_handler = {
952 .ids = acpi_lpss_device_ids,
953};
954
955void __init acpi_lpss_init(void)
956{
957 acpi_scan_add_handler(&lpss_handler);
958}
959
960#endif /* CONFIG_X86_INTEL_LPSS */