Merge tag 'docs-4.16' of git://git.lwn.net/linux
[sfrench/cifs-2.6.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/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 struct lpss_private_data;
73
74 struct lpss_device_desc {
75         unsigned int flags;
76         const char *clk_con_id;
77         unsigned int prv_offset;
78         size_t prv_size_override;
79         struct property_entry *properties;
80         void (*setup)(struct lpss_private_data *pdata);
81 };
82
83 static const struct lpss_device_desc lpss_dma_desc = {
84         .flags = LPSS_CLK,
85 };
86
87 struct lpss_private_data {
88         struct acpi_device *adev;
89         void __iomem *mmio_base;
90         resource_size_t mmio_size;
91         unsigned int fixed_clk_rate;
92         struct clk *clk;
93         const struct lpss_device_desc *dev_desc;
94         u32 prv_reg_ctx[LPSS_PRV_REG_COUNT];
95 };
96
97 /* LPSS run time quirks */
98 static unsigned int lpss_quirks;
99
100 /*
101  * LPSS_QUIRK_ALWAYS_POWER_ON: override power state for LPSS DMA device.
102  *
103  * The LPSS DMA controller has neither _PS0 nor _PS3 method. Moreover
104  * it can be powered off automatically whenever the last LPSS device goes down.
105  * In case of no power any access to the DMA controller will hang the system.
106  * The behaviour is reproduced on some HP laptops based on Intel BayTrail as
107  * well as on ASuS T100TA transformer.
108  *
109  * This quirk overrides power state of entire LPSS island to keep DMA powered
110  * on whenever we have at least one other device in use.
111  */
112 #define LPSS_QUIRK_ALWAYS_POWER_ON      BIT(0)
113
114 /* UART Component Parameter Register */
115 #define LPSS_UART_CPR                   0xF4
116 #define LPSS_UART_CPR_AFCE              BIT(4)
117
118 static void lpss_uart_setup(struct lpss_private_data *pdata)
119 {
120         unsigned int offset;
121         u32 val;
122
123         offset = pdata->dev_desc->prv_offset + LPSS_TX_INT;
124         val = readl(pdata->mmio_base + offset);
125         writel(val | LPSS_TX_INT_MASK, pdata->mmio_base + offset);
126
127         val = readl(pdata->mmio_base + LPSS_UART_CPR);
128         if (!(val & LPSS_UART_CPR_AFCE)) {
129                 offset = pdata->dev_desc->prv_offset + LPSS_GENERAL;
130                 val = readl(pdata->mmio_base + offset);
131                 val |= LPSS_GENERAL_UART_RTS_OVRD;
132                 writel(val, pdata->mmio_base + offset);
133         }
134 }
135
136 static void lpss_deassert_reset(struct lpss_private_data *pdata)
137 {
138         unsigned int offset;
139         u32 val;
140
141         offset = pdata->dev_desc->prv_offset + LPSS_RESETS;
142         val = readl(pdata->mmio_base + offset);
143         val |= LPSS_RESETS_RESET_APB | LPSS_RESETS_RESET_FUNC;
144         writel(val, pdata->mmio_base + offset);
145 }
146
147 /*
148  * BYT PWM used for backlight control by the i915 driver on systems without
149  * the Crystal Cove PMIC.
150  */
151 static struct pwm_lookup byt_pwm_lookup[] = {
152         PWM_LOOKUP_WITH_MODULE("80860F09:00", 0, "0000:00:02.0",
153                                "pwm_backlight", 0, PWM_POLARITY_NORMAL,
154                                "pwm-lpss-platform"),
155 };
156
157 static void byt_pwm_setup(struct lpss_private_data *pdata)
158 {
159         struct acpi_device *adev = pdata->adev;
160
161         /* Only call pwm_add_table for the first PWM controller */
162         if (!adev->pnp.unique_id || strcmp(adev->pnp.unique_id, "1"))
163                 return;
164
165         if (!acpi_dev_present("INT33FD", NULL, -1))
166                 pwm_add_table(byt_pwm_lookup, ARRAY_SIZE(byt_pwm_lookup));
167 }
168
169 #define LPSS_I2C_ENABLE                 0x6c
170
171 static void byt_i2c_setup(struct lpss_private_data *pdata)
172 {
173         lpss_deassert_reset(pdata);
174
175         if (readl(pdata->mmio_base + pdata->dev_desc->prv_offset))
176                 pdata->fixed_clk_rate = 133000000;
177
178         writel(0, pdata->mmio_base + LPSS_I2C_ENABLE);
179 }
180
181 /* BSW PWM used for backlight control by the i915 driver */
182 static struct pwm_lookup bsw_pwm_lookup[] = {
183         PWM_LOOKUP_WITH_MODULE("80862288:00", 0, "0000:00:02.0",
184                                "pwm_backlight", 0, PWM_POLARITY_NORMAL,
185                                "pwm-lpss-platform"),
186 };
187
188 static void bsw_pwm_setup(struct lpss_private_data *pdata)
189 {
190         struct acpi_device *adev = pdata->adev;
191
192         /* Only call pwm_add_table for the first PWM controller */
193         if (!adev->pnp.unique_id || strcmp(adev->pnp.unique_id, "1"))
194                 return;
195
196         pwm_add_table(bsw_pwm_lookup, ARRAY_SIZE(bsw_pwm_lookup));
197 }
198
199 static const struct lpss_device_desc lpt_dev_desc = {
200         .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR,
201         .prv_offset = 0x800,
202 };
203
204 static const struct lpss_device_desc lpt_i2c_dev_desc = {
205         .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_LTR,
206         .prv_offset = 0x800,
207 };
208
209 static struct property_entry uart_properties[] = {
210         PROPERTY_ENTRY_U32("reg-io-width", 4),
211         PROPERTY_ENTRY_U32("reg-shift", 2),
212         PROPERTY_ENTRY_BOOL("snps,uart-16550-compatible"),
213         { },
214 };
215
216 static const struct lpss_device_desc lpt_uart_dev_desc = {
217         .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR,
218         .clk_con_id = "baudclk",
219         .prv_offset = 0x800,
220         .setup = lpss_uart_setup,
221         .properties = uart_properties,
222 };
223
224 static const struct lpss_device_desc lpt_sdio_dev_desc = {
225         .flags = LPSS_LTR,
226         .prv_offset = 0x1000,
227         .prv_size_override = 0x1018,
228 };
229
230 static const struct lpss_device_desc byt_pwm_dev_desc = {
231         .flags = LPSS_SAVE_CTX,
232         .setup = byt_pwm_setup,
233 };
234
235 static const struct lpss_device_desc bsw_pwm_dev_desc = {
236         .flags = LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
237         .setup = bsw_pwm_setup,
238 };
239
240 static const struct lpss_device_desc byt_uart_dev_desc = {
241         .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
242         .clk_con_id = "baudclk",
243         .prv_offset = 0x800,
244         .setup = lpss_uart_setup,
245         .properties = uart_properties,
246 };
247
248 static const struct lpss_device_desc bsw_uart_dev_desc = {
249         .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
250                         | LPSS_NO_D3_DELAY,
251         .clk_con_id = "baudclk",
252         .prv_offset = 0x800,
253         .setup = lpss_uart_setup,
254         .properties = uart_properties,
255 };
256
257 static const struct lpss_device_desc byt_spi_dev_desc = {
258         .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
259         .prv_offset = 0x400,
260 };
261
262 static const struct lpss_device_desc byt_sdio_dev_desc = {
263         .flags = LPSS_CLK,
264 };
265
266 static const struct lpss_device_desc byt_i2c_dev_desc = {
267         .flags = LPSS_CLK | LPSS_SAVE_CTX,
268         .prv_offset = 0x800,
269         .setup = byt_i2c_setup,
270 };
271
272 static const struct lpss_device_desc bsw_i2c_dev_desc = {
273         .flags = LPSS_CLK | LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
274         .prv_offset = 0x800,
275         .setup = byt_i2c_setup,
276 };
277
278 static const struct lpss_device_desc bsw_spi_dev_desc = {
279         .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
280                         | LPSS_NO_D3_DELAY,
281         .prv_offset = 0x400,
282         .setup = lpss_deassert_reset,
283 };
284
285 #define ICPU(model)     { X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, }
286
287 static const struct x86_cpu_id lpss_cpu_ids[] = {
288         ICPU(INTEL_FAM6_ATOM_SILVERMONT1),      /* Valleyview, Bay Trail */
289         ICPU(INTEL_FAM6_ATOM_AIRMONT),  /* Braswell, Cherry Trail */
290         {}
291 };
292
293 #else
294
295 #define LPSS_ADDR(desc) (0UL)
296
297 #endif /* CONFIG_X86_INTEL_LPSS */
298
299 static const struct acpi_device_id acpi_lpss_device_ids[] = {
300         /* Generic LPSS devices */
301         { "INTL9C60", LPSS_ADDR(lpss_dma_desc) },
302
303         /* Lynxpoint LPSS devices */
304         { "INT33C0", LPSS_ADDR(lpt_dev_desc) },
305         { "INT33C1", LPSS_ADDR(lpt_dev_desc) },
306         { "INT33C2", LPSS_ADDR(lpt_i2c_dev_desc) },
307         { "INT33C3", LPSS_ADDR(lpt_i2c_dev_desc) },
308         { "INT33C4", LPSS_ADDR(lpt_uart_dev_desc) },
309         { "INT33C5", LPSS_ADDR(lpt_uart_dev_desc) },
310         { "INT33C6", LPSS_ADDR(lpt_sdio_dev_desc) },
311         { "INT33C7", },
312
313         /* BayTrail LPSS devices */
314         { "80860F09", LPSS_ADDR(byt_pwm_dev_desc) },
315         { "80860F0A", LPSS_ADDR(byt_uart_dev_desc) },
316         { "80860F0E", LPSS_ADDR(byt_spi_dev_desc) },
317         { "80860F14", LPSS_ADDR(byt_sdio_dev_desc) },
318         { "80860F41", LPSS_ADDR(byt_i2c_dev_desc) },
319         { "INT33B2", },
320         { "INT33FC", },
321
322         /* Braswell LPSS devices */
323         { "80862288", LPSS_ADDR(bsw_pwm_dev_desc) },
324         { "8086228A", LPSS_ADDR(bsw_uart_dev_desc) },
325         { "8086228E", LPSS_ADDR(bsw_spi_dev_desc) },
326         { "808622C1", LPSS_ADDR(bsw_i2c_dev_desc) },
327
328         /* Broadwell LPSS devices */
329         { "INT3430", LPSS_ADDR(lpt_dev_desc) },
330         { "INT3431", LPSS_ADDR(lpt_dev_desc) },
331         { "INT3432", LPSS_ADDR(lpt_i2c_dev_desc) },
332         { "INT3433", LPSS_ADDR(lpt_i2c_dev_desc) },
333         { "INT3434", LPSS_ADDR(lpt_uart_dev_desc) },
334         { "INT3435", LPSS_ADDR(lpt_uart_dev_desc) },
335         { "INT3436", LPSS_ADDR(lpt_sdio_dev_desc) },
336         { "INT3437", },
337
338         /* Wildcat Point LPSS devices */
339         { "INT3438", LPSS_ADDR(lpt_dev_desc) },
340
341         { }
342 };
343
344 #ifdef CONFIG_X86_INTEL_LPSS
345
346 static int is_memory(struct acpi_resource *res, void *not_used)
347 {
348         struct resource r;
349         return !acpi_dev_resource_memory(res, &r);
350 }
351
352 /* LPSS main clock device. */
353 static struct platform_device *lpss_clk_dev;
354
355 static inline void lpt_register_clock_device(void)
356 {
357         lpss_clk_dev = platform_device_register_simple("clk-lpt", -1, NULL, 0);
358 }
359
360 static int register_device_clock(struct acpi_device *adev,
361                                  struct lpss_private_data *pdata)
362 {
363         const struct lpss_device_desc *dev_desc = pdata->dev_desc;
364         const char *devname = dev_name(&adev->dev);
365         struct clk *clk;
366         struct lpss_clk_data *clk_data;
367         const char *parent, *clk_name;
368         void __iomem *prv_base;
369
370         if (!lpss_clk_dev)
371                 lpt_register_clock_device();
372
373         clk_data = platform_get_drvdata(lpss_clk_dev);
374         if (!clk_data)
375                 return -ENODEV;
376         clk = clk_data->clk;
377
378         if (!pdata->mmio_base
379             || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE)
380                 return -ENODATA;
381
382         parent = clk_data->name;
383         prv_base = pdata->mmio_base + dev_desc->prv_offset;
384
385         if (pdata->fixed_clk_rate) {
386                 clk = clk_register_fixed_rate(NULL, devname, parent, 0,
387                                               pdata->fixed_clk_rate);
388                 goto out;
389         }
390
391         if (dev_desc->flags & LPSS_CLK_GATE) {
392                 clk = clk_register_gate(NULL, devname, parent, 0,
393                                         prv_base, 0, 0, NULL);
394                 parent = devname;
395         }
396
397         if (dev_desc->flags & LPSS_CLK_DIVIDER) {
398                 /* Prevent division by zero */
399                 if (!readl(prv_base))
400                         writel(LPSS_CLK_DIVIDER_DEF_MASK, prv_base);
401
402                 clk_name = kasprintf(GFP_KERNEL, "%s-div", devname);
403                 if (!clk_name)
404                         return -ENOMEM;
405                 clk = clk_register_fractional_divider(NULL, clk_name, parent,
406                                                       0, prv_base,
407                                                       1, 15, 16, 15, 0, NULL);
408                 parent = clk_name;
409
410                 clk_name = kasprintf(GFP_KERNEL, "%s-update", devname);
411                 if (!clk_name) {
412                         kfree(parent);
413                         return -ENOMEM;
414                 }
415                 clk = clk_register_gate(NULL, clk_name, parent,
416                                         CLK_SET_RATE_PARENT | CLK_SET_RATE_GATE,
417                                         prv_base, 31, 0, NULL);
418                 kfree(parent);
419                 kfree(clk_name);
420         }
421 out:
422         if (IS_ERR(clk))
423                 return PTR_ERR(clk);
424
425         pdata->clk = clk;
426         clk_register_clkdev(clk, dev_desc->clk_con_id, devname);
427         return 0;
428 }
429
430 struct lpss_device_links {
431         const char *supplier_hid;
432         const char *supplier_uid;
433         const char *consumer_hid;
434         const char *consumer_uid;
435         u32 flags;
436 };
437
438 /*
439  * The _DEP method is used to identify dependencies but instead of creating
440  * device links for every handle in _DEP, only links in the following list are
441  * created. That is necessary because, in the general case, _DEP can refer to
442  * devices that might not have drivers, or that are on different buses, or where
443  * the supplier is not enumerated until after the consumer is probed.
444  */
445 static const struct lpss_device_links lpss_device_links[] = {
446         {"808622C1", "7", "80860F14", "3", DL_FLAG_PM_RUNTIME},
447 };
448
449 static bool hid_uid_match(const char *hid1, const char *uid1,
450                           const char *hid2, const char *uid2)
451 {
452         return !strcmp(hid1, hid2) && uid1 && uid2 && !strcmp(uid1, uid2);
453 }
454
455 static bool acpi_lpss_is_supplier(struct acpi_device *adev,
456                                   const struct lpss_device_links *link)
457 {
458         return hid_uid_match(acpi_device_hid(adev), acpi_device_uid(adev),
459                              link->supplier_hid, link->supplier_uid);
460 }
461
462 static bool acpi_lpss_is_consumer(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->consumer_hid, link->consumer_uid);
467 }
468
469 struct hid_uid {
470         const char *hid;
471         const char *uid;
472 };
473
474 static int match_hid_uid(struct device *dev, void *data)
475 {
476         struct acpi_device *adev = ACPI_COMPANION(dev);
477         struct hid_uid *id = data;
478
479         if (!adev)
480                 return 0;
481
482         return hid_uid_match(acpi_device_hid(adev), acpi_device_uid(adev),
483                              id->hid, id->uid);
484 }
485
486 static struct device *acpi_lpss_find_device(const char *hid, const char *uid)
487 {
488         struct hid_uid data = {
489                 .hid = hid,
490                 .uid = uid,
491         };
492
493         return bus_find_device(&platform_bus_type, NULL, &data, match_hid_uid);
494 }
495
496 static bool acpi_lpss_dep(struct acpi_device *adev, acpi_handle handle)
497 {
498         struct acpi_handle_list dep_devices;
499         acpi_status status;
500         int i;
501
502         if (!acpi_has_method(adev->handle, "_DEP"))
503                 return false;
504
505         status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
506                                          &dep_devices);
507         if (ACPI_FAILURE(status)) {
508                 dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
509                 return false;
510         }
511
512         for (i = 0; i < dep_devices.count; i++) {
513                 if (dep_devices.handles[i] == handle)
514                         return true;
515         }
516
517         return false;
518 }
519
520 static void acpi_lpss_link_consumer(struct device *dev1,
521                                     const struct lpss_device_links *link)
522 {
523         struct device *dev2;
524
525         dev2 = acpi_lpss_find_device(link->consumer_hid, link->consumer_uid);
526         if (!dev2)
527                 return;
528
529         if (acpi_lpss_dep(ACPI_COMPANION(dev2), ACPI_HANDLE(dev1)))
530                 device_link_add(dev2, dev1, link->flags);
531
532         put_device(dev2);
533 }
534
535 static void acpi_lpss_link_supplier(struct device *dev1,
536                                     const struct lpss_device_links *link)
537 {
538         struct device *dev2;
539
540         dev2 = acpi_lpss_find_device(link->supplier_hid, link->supplier_uid);
541         if (!dev2)
542                 return;
543
544         if (acpi_lpss_dep(ACPI_COMPANION(dev1), ACPI_HANDLE(dev2)))
545                 device_link_add(dev1, dev2, link->flags);
546
547         put_device(dev2);
548 }
549
550 static void acpi_lpss_create_device_links(struct acpi_device *adev,
551                                           struct platform_device *pdev)
552 {
553         int i;
554
555         for (i = 0; i < ARRAY_SIZE(lpss_device_links); i++) {
556                 const struct lpss_device_links *link = &lpss_device_links[i];
557
558                 if (acpi_lpss_is_supplier(adev, link))
559                         acpi_lpss_link_consumer(&pdev->dev, link);
560
561                 if (acpi_lpss_is_consumer(adev, link))
562                         acpi_lpss_link_supplier(&pdev->dev, link);
563         }
564 }
565
566 static int acpi_lpss_create_device(struct acpi_device *adev,
567                                    const struct acpi_device_id *id)
568 {
569         const struct lpss_device_desc *dev_desc;
570         struct lpss_private_data *pdata;
571         struct resource_entry *rentry;
572         struct list_head resource_list;
573         struct platform_device *pdev;
574         int ret;
575
576         dev_desc = (const struct lpss_device_desc *)id->driver_data;
577         if (!dev_desc) {
578                 pdev = acpi_create_platform_device(adev, NULL);
579                 return IS_ERR_OR_NULL(pdev) ? PTR_ERR(pdev) : 1;
580         }
581         pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
582         if (!pdata)
583                 return -ENOMEM;
584
585         INIT_LIST_HEAD(&resource_list);
586         ret = acpi_dev_get_resources(adev, &resource_list, is_memory, NULL);
587         if (ret < 0)
588                 goto err_out;
589
590         list_for_each_entry(rentry, &resource_list, node)
591                 if (resource_type(rentry->res) == IORESOURCE_MEM) {
592                         if (dev_desc->prv_size_override)
593                                 pdata->mmio_size = dev_desc->prv_size_override;
594                         else
595                                 pdata->mmio_size = resource_size(rentry->res);
596                         pdata->mmio_base = ioremap(rentry->res->start,
597                                                    pdata->mmio_size);
598                         break;
599                 }
600
601         acpi_dev_free_resource_list(&resource_list);
602
603         if (!pdata->mmio_base) {
604                 /* Avoid acpi_bus_attach() instantiating a pdev for this dev. */
605                 adev->pnp.type.platform_id = 0;
606                 /* Skip the device, but continue the namespace scan. */
607                 ret = 0;
608                 goto err_out;
609         }
610
611         pdata->adev = adev;
612         pdata->dev_desc = dev_desc;
613
614         if (dev_desc->setup)
615                 dev_desc->setup(pdata);
616
617         if (dev_desc->flags & LPSS_CLK) {
618                 ret = register_device_clock(adev, pdata);
619                 if (ret) {
620                         /* Skip the device, but continue the namespace scan. */
621                         ret = 0;
622                         goto err_out;
623                 }
624         }
625
626         /*
627          * This works around a known issue in ACPI tables where LPSS devices
628          * have _PS0 and _PS3 without _PSC (and no power resources), so
629          * acpi_bus_init_power() will assume that the BIOS has put them into D0.
630          */
631         ret = acpi_device_fix_up_power(adev);
632         if (ret) {
633                 /* Skip the device, but continue the namespace scan. */
634                 ret = 0;
635                 goto err_out;
636         }
637
638         adev->driver_data = pdata;
639         pdev = acpi_create_platform_device(adev, dev_desc->properties);
640         if (!IS_ERR_OR_NULL(pdev)) {
641                 acpi_lpss_create_device_links(adev, pdev);
642                 return 1;
643         }
644
645         ret = PTR_ERR(pdev);
646         adev->driver_data = NULL;
647
648  err_out:
649         kfree(pdata);
650         return ret;
651 }
652
653 static u32 __lpss_reg_read(struct lpss_private_data *pdata, unsigned int reg)
654 {
655         return readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
656 }
657
658 static void __lpss_reg_write(u32 val, struct lpss_private_data *pdata,
659                              unsigned int reg)
660 {
661         writel(val, pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
662 }
663
664 static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val)
665 {
666         struct acpi_device *adev;
667         struct lpss_private_data *pdata;
668         unsigned long flags;
669         int ret;
670
671         ret = acpi_bus_get_device(ACPI_HANDLE(dev), &adev);
672         if (WARN_ON(ret))
673                 return ret;
674
675         spin_lock_irqsave(&dev->power.lock, flags);
676         if (pm_runtime_suspended(dev)) {
677                 ret = -EAGAIN;
678                 goto out;
679         }
680         pdata = acpi_driver_data(adev);
681         if (WARN_ON(!pdata || !pdata->mmio_base)) {
682                 ret = -ENODEV;
683                 goto out;
684         }
685         *val = __lpss_reg_read(pdata, reg);
686
687  out:
688         spin_unlock_irqrestore(&dev->power.lock, flags);
689         return ret;
690 }
691
692 static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr,
693                              char *buf)
694 {
695         u32 ltr_value = 0;
696         unsigned int reg;
697         int ret;
698
699         reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR;
700         ret = lpss_reg_read(dev, reg, &ltr_value);
701         if (ret)
702                 return ret;
703
704         return snprintf(buf, PAGE_SIZE, "%08x\n", ltr_value);
705 }
706
707 static ssize_t lpss_ltr_mode_show(struct device *dev,
708                                   struct device_attribute *attr, char *buf)
709 {
710         u32 ltr_mode = 0;
711         char *outstr;
712         int ret;
713
714         ret = lpss_reg_read(dev, LPSS_GENERAL, &ltr_mode);
715         if (ret)
716                 return ret;
717
718         outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto";
719         return sprintf(buf, "%s\n", outstr);
720 }
721
722 static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL);
723 static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL);
724 static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL);
725
726 static struct attribute *lpss_attrs[] = {
727         &dev_attr_auto_ltr.attr,
728         &dev_attr_sw_ltr.attr,
729         &dev_attr_ltr_mode.attr,
730         NULL,
731 };
732
733 static const struct attribute_group lpss_attr_group = {
734         .attrs = lpss_attrs,
735         .name = "lpss_ltr",
736 };
737
738 static void acpi_lpss_set_ltr(struct device *dev, s32 val)
739 {
740         struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
741         u32 ltr_mode, ltr_val;
742
743         ltr_mode = __lpss_reg_read(pdata, LPSS_GENERAL);
744         if (val < 0) {
745                 if (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) {
746                         ltr_mode &= ~LPSS_GENERAL_LTR_MODE_SW;
747                         __lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
748                 }
749                 return;
750         }
751         ltr_val = __lpss_reg_read(pdata, LPSS_SW_LTR) & ~LPSS_LTR_SNOOP_MASK;
752         if (val >= LPSS_LTR_SNOOP_LAT_CUTOFF) {
753                 ltr_val |= LPSS_LTR_SNOOP_LAT_32US;
754                 val = LPSS_LTR_MAX_VAL;
755         } else if (val > LPSS_LTR_MAX_VAL) {
756                 ltr_val |= LPSS_LTR_SNOOP_LAT_32US | LPSS_LTR_SNOOP_REQ;
757                 val >>= LPSS_LTR_SNOOP_LAT_SHIFT;
758         } else {
759                 ltr_val |= LPSS_LTR_SNOOP_LAT_1US | LPSS_LTR_SNOOP_REQ;
760         }
761         ltr_val |= val;
762         __lpss_reg_write(ltr_val, pdata, LPSS_SW_LTR);
763         if (!(ltr_mode & LPSS_GENERAL_LTR_MODE_SW)) {
764                 ltr_mode |= LPSS_GENERAL_LTR_MODE_SW;
765                 __lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
766         }
767 }
768
769 #ifdef CONFIG_PM
770 /**
771  * acpi_lpss_save_ctx() - Save the private registers of LPSS device
772  * @dev: LPSS device
773  * @pdata: pointer to the private data of the LPSS device
774  *
775  * Most LPSS devices have private registers which may loose their context when
776  * the device is powered down. acpi_lpss_save_ctx() saves those registers into
777  * prv_reg_ctx array.
778  */
779 static void acpi_lpss_save_ctx(struct device *dev,
780                                struct lpss_private_data *pdata)
781 {
782         unsigned int i;
783
784         for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
785                 unsigned long offset = i * sizeof(u32);
786
787                 pdata->prv_reg_ctx[i] = __lpss_reg_read(pdata, offset);
788                 dev_dbg(dev, "saving 0x%08x from LPSS reg at offset 0x%02lx\n",
789                         pdata->prv_reg_ctx[i], offset);
790         }
791 }
792
793 /**
794  * acpi_lpss_restore_ctx() - Restore the private registers of LPSS device
795  * @dev: LPSS device
796  * @pdata: pointer to the private data of the LPSS device
797  *
798  * Restores the registers that were previously stored with acpi_lpss_save_ctx().
799  */
800 static void acpi_lpss_restore_ctx(struct device *dev,
801                                   struct lpss_private_data *pdata)
802 {
803         unsigned int i;
804
805         for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
806                 unsigned long offset = i * sizeof(u32);
807
808                 __lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset);
809                 dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n",
810                         pdata->prv_reg_ctx[i], offset);
811         }
812 }
813
814 static void acpi_lpss_d3_to_d0_delay(struct lpss_private_data *pdata)
815 {
816         /*
817          * The following delay is needed or the subsequent write operations may
818          * fail. The LPSS devices are actually PCI devices and the PCI spec
819          * expects 10ms delay before the device can be accessed after D3 to D0
820          * transition. However some platforms like BSW does not need this delay.
821          */
822         unsigned int delay = 10;        /* default 10ms delay */
823
824         if (pdata->dev_desc->flags & LPSS_NO_D3_DELAY)
825                 delay = 0;
826
827         msleep(delay);
828 }
829
830 static int acpi_lpss_activate(struct device *dev)
831 {
832         struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
833         int ret;
834
835         ret = acpi_dev_resume(dev);
836         if (ret)
837                 return ret;
838
839         acpi_lpss_d3_to_d0_delay(pdata);
840
841         /*
842          * This is called only on ->probe() stage where a device is either in
843          * known state defined by BIOS or most likely powered off. Due to this
844          * we have to deassert reset line to be sure that ->probe() will
845          * recognize the device.
846          */
847         if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
848                 lpss_deassert_reset(pdata);
849
850         return 0;
851 }
852
853 static void acpi_lpss_dismiss(struct device *dev)
854 {
855         acpi_dev_suspend(dev, false);
856 }
857
858 /* IOSF SB for LPSS island */
859 #define LPSS_IOSF_UNIT_LPIOEP           0xA0
860 #define LPSS_IOSF_UNIT_LPIO1            0xAB
861 #define LPSS_IOSF_UNIT_LPIO2            0xAC
862
863 #define LPSS_IOSF_PMCSR                 0x84
864 #define LPSS_PMCSR_D0                   0
865 #define LPSS_PMCSR_D3hot                3
866 #define LPSS_PMCSR_Dx_MASK              GENMASK(1, 0)
867
868 #define LPSS_IOSF_GPIODEF0              0x154
869 #define LPSS_GPIODEF0_DMA1_D3           BIT(2)
870 #define LPSS_GPIODEF0_DMA2_D3           BIT(3)
871 #define LPSS_GPIODEF0_DMA_D3_MASK       GENMASK(3, 2)
872 #define LPSS_GPIODEF0_DMA_LLP           BIT(13)
873
874 static DEFINE_MUTEX(lpss_iosf_mutex);
875
876 static void lpss_iosf_enter_d3_state(void)
877 {
878         u32 value1 = 0;
879         u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
880         u32 value2 = LPSS_PMCSR_D3hot;
881         u32 mask2 = LPSS_PMCSR_Dx_MASK;
882         /*
883          * PMC provides an information about actual status of the LPSS devices.
884          * Here we read the values related to LPSS power island, i.e. LPSS
885          * devices, excluding both LPSS DMA controllers, along with SCC domain.
886          */
887         u32 func_dis, d3_sts_0, pmc_status, pmc_mask = 0xfe000ffe;
888         int ret;
889
890         ret = pmc_atom_read(PMC_FUNC_DIS, &func_dis);
891         if (ret)
892                 return;
893
894         mutex_lock(&lpss_iosf_mutex);
895
896         ret = pmc_atom_read(PMC_D3_STS_0, &d3_sts_0);
897         if (ret)
898                 goto exit;
899
900         /*
901          * Get the status of entire LPSS power island per device basis.
902          * Shutdown both LPSS DMA controllers if and only if all other devices
903          * are already in D3hot.
904          */
905         pmc_status = (~(d3_sts_0 | func_dis)) & pmc_mask;
906         if (pmc_status)
907                 goto exit;
908
909         iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
910                         LPSS_IOSF_PMCSR, value2, mask2);
911
912         iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
913                         LPSS_IOSF_PMCSR, value2, mask2);
914
915         iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
916                         LPSS_IOSF_GPIODEF0, value1, mask1);
917 exit:
918         mutex_unlock(&lpss_iosf_mutex);
919 }
920
921 static void lpss_iosf_exit_d3_state(void)
922 {
923         u32 value1 = LPSS_GPIODEF0_DMA1_D3 | LPSS_GPIODEF0_DMA2_D3 |
924                      LPSS_GPIODEF0_DMA_LLP;
925         u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
926         u32 value2 = LPSS_PMCSR_D0;
927         u32 mask2 = LPSS_PMCSR_Dx_MASK;
928
929         mutex_lock(&lpss_iosf_mutex);
930
931         iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
932                         LPSS_IOSF_GPIODEF0, value1, mask1);
933
934         iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
935                         LPSS_IOSF_PMCSR, value2, mask2);
936
937         iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
938                         LPSS_IOSF_PMCSR, value2, mask2);
939
940         mutex_unlock(&lpss_iosf_mutex);
941 }
942
943 static int acpi_lpss_suspend(struct device *dev, bool wakeup)
944 {
945         struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
946         int ret;
947
948         if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
949                 acpi_lpss_save_ctx(dev, pdata);
950
951         ret = acpi_dev_suspend(dev, wakeup);
952
953         /*
954          * This call must be last in the sequence, otherwise PMC will return
955          * wrong status for devices being about to be powered off. See
956          * lpss_iosf_enter_d3_state() for further information.
957          */
958         if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
959                 lpss_iosf_enter_d3_state();
960
961         return ret;
962 }
963
964 static int acpi_lpss_resume(struct device *dev)
965 {
966         struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
967         int ret;
968
969         /*
970          * This call is kept first to be in symmetry with
971          * acpi_lpss_runtime_suspend() one.
972          */
973         if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
974                 lpss_iosf_exit_d3_state();
975
976         ret = acpi_dev_resume(dev);
977         if (ret)
978                 return ret;
979
980         acpi_lpss_d3_to_d0_delay(pdata);
981
982         if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
983                 acpi_lpss_restore_ctx(dev, pdata);
984
985         return 0;
986 }
987
988 #ifdef CONFIG_PM_SLEEP
989 static int acpi_lpss_suspend_late(struct device *dev)
990 {
991         int ret;
992
993         if (dev_pm_smart_suspend_and_suspended(dev))
994                 return 0;
995
996         ret = pm_generic_suspend_late(dev);
997         return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
998 }
999
1000 static int acpi_lpss_resume_early(struct device *dev)
1001 {
1002         int ret = acpi_lpss_resume(dev);
1003
1004         return ret ? ret : pm_generic_resume_early(dev);
1005 }
1006 #endif /* CONFIG_PM_SLEEP */
1007
1008 static int acpi_lpss_runtime_suspend(struct device *dev)
1009 {
1010         int ret = pm_generic_runtime_suspend(dev);
1011
1012         return ret ? ret : acpi_lpss_suspend(dev, true);
1013 }
1014
1015 static int acpi_lpss_runtime_resume(struct device *dev)
1016 {
1017         int ret = acpi_lpss_resume(dev);
1018
1019         return ret ? ret : pm_generic_runtime_resume(dev);
1020 }
1021 #endif /* CONFIG_PM */
1022
1023 static struct dev_pm_domain acpi_lpss_pm_domain = {
1024 #ifdef CONFIG_PM
1025         .activate = acpi_lpss_activate,
1026         .dismiss = acpi_lpss_dismiss,
1027 #endif
1028         .ops = {
1029 #ifdef CONFIG_PM
1030 #ifdef CONFIG_PM_SLEEP
1031                 .prepare = acpi_subsys_prepare,
1032                 .complete = acpi_subsys_complete,
1033                 .suspend = acpi_subsys_suspend,
1034                 .suspend_late = acpi_lpss_suspend_late,
1035                 .suspend_noirq = acpi_subsys_suspend_noirq,
1036                 .resume_noirq = acpi_subsys_resume_noirq,
1037                 .resume_early = acpi_lpss_resume_early,
1038                 .freeze = acpi_subsys_freeze,
1039                 .freeze_late = acpi_subsys_freeze_late,
1040                 .freeze_noirq = acpi_subsys_freeze_noirq,
1041                 .thaw_noirq = acpi_subsys_thaw_noirq,
1042                 .poweroff = acpi_subsys_suspend,
1043                 .poweroff_late = acpi_lpss_suspend_late,
1044                 .poweroff_noirq = acpi_subsys_suspend_noirq,
1045                 .restore_noirq = acpi_subsys_resume_noirq,
1046                 .restore_early = acpi_lpss_resume_early,
1047 #endif
1048                 .runtime_suspend = acpi_lpss_runtime_suspend,
1049                 .runtime_resume = acpi_lpss_runtime_resume,
1050 #endif
1051         },
1052 };
1053
1054 static int acpi_lpss_platform_notify(struct notifier_block *nb,
1055                                      unsigned long action, void *data)
1056 {
1057         struct platform_device *pdev = to_platform_device(data);
1058         struct lpss_private_data *pdata;
1059         struct acpi_device *adev;
1060         const struct acpi_device_id *id;
1061
1062         id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev);
1063         if (!id || !id->driver_data)
1064                 return 0;
1065
1066         if (acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev))
1067                 return 0;
1068
1069         pdata = acpi_driver_data(adev);
1070         if (!pdata)
1071                 return 0;
1072
1073         if (pdata->mmio_base &&
1074             pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) {
1075                 dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n");
1076                 return 0;
1077         }
1078
1079         switch (action) {
1080         case BUS_NOTIFY_BIND_DRIVER:
1081                 dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1082                 break;
1083         case BUS_NOTIFY_DRIVER_NOT_BOUND:
1084         case BUS_NOTIFY_UNBOUND_DRIVER:
1085                 dev_pm_domain_set(&pdev->dev, NULL);
1086                 break;
1087         case BUS_NOTIFY_ADD_DEVICE:
1088                 dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1089                 if (pdata->dev_desc->flags & LPSS_LTR)
1090                         return sysfs_create_group(&pdev->dev.kobj,
1091                                                   &lpss_attr_group);
1092                 break;
1093         case BUS_NOTIFY_DEL_DEVICE:
1094                 if (pdata->dev_desc->flags & LPSS_LTR)
1095                         sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group);
1096                 dev_pm_domain_set(&pdev->dev, NULL);
1097                 break;
1098         default:
1099                 break;
1100         }
1101
1102         return 0;
1103 }
1104
1105 static struct notifier_block acpi_lpss_nb = {
1106         .notifier_call = acpi_lpss_platform_notify,
1107 };
1108
1109 static void acpi_lpss_bind(struct device *dev)
1110 {
1111         struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1112
1113         if (!pdata || !pdata->mmio_base || !(pdata->dev_desc->flags & LPSS_LTR))
1114                 return;
1115
1116         if (pdata->mmio_size >= pdata->dev_desc->prv_offset + LPSS_LTR_SIZE)
1117                 dev->power.set_latency_tolerance = acpi_lpss_set_ltr;
1118         else
1119                 dev_err(dev, "MMIO size insufficient to access LTR\n");
1120 }
1121
1122 static void acpi_lpss_unbind(struct device *dev)
1123 {
1124         dev->power.set_latency_tolerance = NULL;
1125 }
1126
1127 static struct acpi_scan_handler lpss_handler = {
1128         .ids = acpi_lpss_device_ids,
1129         .attach = acpi_lpss_create_device,
1130         .bind = acpi_lpss_bind,
1131         .unbind = acpi_lpss_unbind,
1132 };
1133
1134 void __init acpi_lpss_init(void)
1135 {
1136         const struct x86_cpu_id *id;
1137         int ret;
1138
1139         ret = lpt_clk_init();
1140         if (ret)
1141                 return;
1142
1143         id = x86_match_cpu(lpss_cpu_ids);
1144         if (id)
1145                 lpss_quirks |= LPSS_QUIRK_ALWAYS_POWER_ON;
1146
1147         bus_register_notifier(&platform_bus_type, &acpi_lpss_nb);
1148         acpi_scan_add_handler(&lpss_handler);
1149 }
1150
1151 #else
1152
1153 static struct acpi_scan_handler lpss_handler = {
1154         .ids = acpi_lpss_device_ids,
1155 };
1156
1157 void __init acpi_lpss_init(void)
1158 {
1159         acpi_scan_add_handler(&lpss_handler);
1160 }
1161
1162 #endif /* CONFIG_X86_INTEL_LPSS */