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