2 * ACPI support for Intel Lynxpoint LPSS.
4 * Copyright (C) 2013, Intel Corporation
5 * Authors: Mika Westerberg <mika.westerberg@linux.intel.com>
6 * Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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.
13 #include <linux/acpi.h>
14 #include <linux/clk.h>
15 #include <linux/clkdev.h>
16 #include <linux/clk-provider.h>
17 #include <linux/err.h>
19 #include <linux/platform_device.h>
20 #include <linux/platform_data/clk-lpss.h>
21 #include <linux/pm_runtime.h>
25 ACPI_MODULE_NAME("acpi_lpss");
27 #define LPSS_CLK_SIZE 0x04
28 #define LPSS_LTR_SIZE 0x18
30 /* Offsets relative to LPSS_PRIVATE_OFFSET */
31 #define LPSS_GENERAL 0x08
32 #define LPSS_GENERAL_LTR_MODE_SW BIT(2)
33 #define LPSS_GENERAL_UART_RTS_OVRD BIT(3)
34 #define LPSS_SW_LTR 0x10
35 #define LPSS_AUTO_LTR 0x14
36 #define LPSS_LTR_SNOOP_REQ BIT(15)
37 #define LPSS_LTR_SNOOP_MASK 0x0000FFFF
38 #define LPSS_LTR_SNOOP_LAT_1US 0x800
39 #define LPSS_LTR_SNOOP_LAT_32US 0xC00
40 #define LPSS_LTR_SNOOP_LAT_SHIFT 5
41 #define LPSS_LTR_SNOOP_LAT_CUTOFF 3000
42 #define LPSS_LTR_MAX_VAL 0x3FF
43 #define LPSS_TX_INT 0x20
44 #define LPSS_TX_INT_MASK BIT(1)
46 struct lpss_shared_clock
{
52 struct lpss_private_data
;
54 struct lpss_device_desc
{
56 const char *clkdev_name
;
58 unsigned int prv_offset
;
59 size_t prv_size_override
;
61 struct lpss_shared_clock
*shared_clock
;
62 void (*setup
)(struct lpss_private_data
*pdata
);
65 static struct lpss_device_desc lpss_dma_desc
= {
67 .clkdev_name
= "hclk",
70 struct lpss_private_data
{
71 void __iomem
*mmio_base
;
72 resource_size_t mmio_size
;
74 const struct lpss_device_desc
*dev_desc
;
77 static void lpss_uart_setup(struct lpss_private_data
*pdata
)
82 offset
= pdata
->dev_desc
->prv_offset
+ LPSS_TX_INT
;
83 reg
= readl(pdata
->mmio_base
+ offset
);
84 writel(reg
| LPSS_TX_INT_MASK
, pdata
->mmio_base
+ offset
);
86 offset
= pdata
->dev_desc
->prv_offset
+ LPSS_GENERAL
;
87 reg
= readl(pdata
->mmio_base
+ offset
);
88 writel(reg
| LPSS_GENERAL_UART_RTS_OVRD
, pdata
->mmio_base
+ offset
);
91 static struct lpss_device_desc lpt_dev_desc
= {
98 static struct lpss_device_desc lpt_uart_dev_desc
= {
101 .ltr_required
= true,
103 .setup
= lpss_uart_setup
,
106 static struct lpss_device_desc lpt_sdio_dev_desc
= {
107 .prv_offset
= 0x1000,
108 .prv_size_override
= 0x1018,
109 .ltr_required
= true,
112 static struct lpss_shared_clock pwm_clock
= {
117 static struct lpss_device_desc byt_pwm_dev_desc
= {
118 .clk_required
= true,
119 .shared_clock
= &pwm_clock
,
122 static struct lpss_shared_clock uart_clock
= {
127 static struct lpss_device_desc byt_uart_dev_desc
= {
128 .clk_required
= true,
131 .shared_clock
= &uart_clock
,
132 .setup
= lpss_uart_setup
,
135 static struct lpss_shared_clock spi_clock
= {
140 static struct lpss_device_desc byt_spi_dev_desc
= {
141 .clk_required
= true,
144 .shared_clock
= &spi_clock
,
147 static struct lpss_device_desc byt_sdio_dev_desc
= {
148 .clk_required
= true,
151 static struct lpss_shared_clock i2c_clock
= {
156 static struct lpss_device_desc byt_i2c_dev_desc
= {
157 .clk_required
= true,
159 .shared_clock
= &i2c_clock
,
162 static const struct acpi_device_id acpi_lpss_device_ids
[] = {
163 /* Generic LPSS devices */
164 { "INTL9C60", (unsigned long)&lpss_dma_desc
},
166 /* Lynxpoint LPSS devices */
167 { "INT33C0", (unsigned long)&lpt_dev_desc
},
168 { "INT33C1", (unsigned long)&lpt_dev_desc
},
169 { "INT33C2", (unsigned long)&lpt_dev_desc
},
170 { "INT33C3", (unsigned long)&lpt_dev_desc
},
171 { "INT33C4", (unsigned long)&lpt_uart_dev_desc
},
172 { "INT33C5", (unsigned long)&lpt_uart_dev_desc
},
173 { "INT33C6", (unsigned long)&lpt_sdio_dev_desc
},
176 /* BayTrail LPSS devices */
177 { "80860F09", (unsigned long)&byt_pwm_dev_desc
},
178 { "80860F0A", (unsigned long)&byt_uart_dev_desc
},
179 { "80860F0E", (unsigned long)&byt_spi_dev_desc
},
180 { "80860F14", (unsigned long)&byt_sdio_dev_desc
},
181 { "80860F41", (unsigned long)&byt_i2c_dev_desc
},
185 { "INT3430", (unsigned long)&lpt_dev_desc
},
186 { "INT3431", (unsigned long)&lpt_dev_desc
},
187 { "INT3432", (unsigned long)&lpt_dev_desc
},
188 { "INT3433", (unsigned long)&lpt_dev_desc
},
189 { "INT3434", (unsigned long)&lpt_uart_dev_desc
},
190 { "INT3435", (unsigned long)&lpt_uart_dev_desc
},
191 { "INT3436", (unsigned long)&lpt_sdio_dev_desc
},
197 static int is_memory(struct acpi_resource
*res
, void *not_used
)
200 return !acpi_dev_resource_memory(res
, &r
);
203 /* LPSS main clock device. */
204 static struct platform_device
*lpss_clk_dev
;
206 static inline void lpt_register_clock_device(void)
208 lpss_clk_dev
= platform_device_register_simple("clk-lpt", -1, NULL
, 0);
211 static int register_device_clock(struct acpi_device
*adev
,
212 struct lpss_private_data
*pdata
)
214 const struct lpss_device_desc
*dev_desc
= pdata
->dev_desc
;
215 struct lpss_shared_clock
*shared_clock
= dev_desc
->shared_clock
;
216 struct clk
*clk
= ERR_PTR(-ENODEV
);
217 struct lpss_clk_data
*clk_data
;
221 lpt_register_clock_device();
223 clk_data
= platform_get_drvdata(lpss_clk_dev
);
227 if (dev_desc
->clkdev_name
) {
228 clk_register_clkdev(clk_data
->clk
, dev_desc
->clkdev_name
,
229 dev_name(&adev
->dev
));
233 if (!pdata
->mmio_base
234 || pdata
->mmio_size
< dev_desc
->prv_offset
+ LPSS_CLK_SIZE
)
237 parent
= clk_data
->name
;
240 clk
= shared_clock
->clk
;
242 clk
= clk_register_fixed_rate(NULL
, shared_clock
->name
,
245 shared_clock
->clk
= clk
;
247 parent
= shared_clock
->name
;
250 if (dev_desc
->clk_gate
) {
251 clk
= clk_register_gate(NULL
, dev_name(&adev
->dev
), parent
, 0,
252 pdata
->mmio_base
+ dev_desc
->prv_offset
,
260 clk_register_clkdev(clk
, NULL
, dev_name(&adev
->dev
));
264 static int acpi_lpss_create_device(struct acpi_device
*adev
,
265 const struct acpi_device_id
*id
)
267 struct lpss_device_desc
*dev_desc
;
268 struct lpss_private_data
*pdata
;
269 struct resource_list_entry
*rentry
;
270 struct list_head resource_list
;
273 dev_desc
= (struct lpss_device_desc
*)id
->driver_data
;
275 return acpi_create_platform_device(adev
, id
);
277 pdata
= kzalloc(sizeof(*pdata
), GFP_KERNEL
);
281 INIT_LIST_HEAD(&resource_list
);
282 ret
= acpi_dev_get_resources(adev
, &resource_list
, is_memory
, NULL
);
286 list_for_each_entry(rentry
, &resource_list
, node
)
287 if (resource_type(&rentry
->res
) == IORESOURCE_MEM
) {
288 if (dev_desc
->prv_size_override
)
289 pdata
->mmio_size
= dev_desc
->prv_size_override
;
291 pdata
->mmio_size
= resource_size(&rentry
->res
);
292 pdata
->mmio_base
= ioremap(rentry
->res
.start
,
297 acpi_dev_free_resource_list(&resource_list
);
299 pdata
->dev_desc
= dev_desc
;
301 if (dev_desc
->clk_required
) {
302 ret
= register_device_clock(adev
, pdata
);
304 /* Skip the device, but continue the namespace scan. */
311 * This works around a known issue in ACPI tables where LPSS devices
312 * have _PS0 and _PS3 without _PSC (and no power resources), so
313 * acpi_bus_init_power() will assume that the BIOS has put them into D0.
315 ret
= acpi_device_fix_up_power(adev
);
317 /* Skip the device, but continue the namespace scan. */
323 dev_desc
->setup(pdata
);
325 adev
->driver_data
= pdata
;
326 ret
= acpi_create_platform_device(adev
, id
);
330 adev
->driver_data
= NULL
;
337 static u32
__lpss_reg_read(struct lpss_private_data
*pdata
, unsigned int reg
)
339 return readl(pdata
->mmio_base
+ pdata
->dev_desc
->prv_offset
+ reg
);
342 static void __lpss_reg_write(u32 val
, struct lpss_private_data
*pdata
,
345 writel(val
, pdata
->mmio_base
+ pdata
->dev_desc
->prv_offset
+ reg
);
348 static int lpss_reg_read(struct device
*dev
, unsigned int reg
, u32
*val
)
350 struct acpi_device
*adev
;
351 struct lpss_private_data
*pdata
;
355 ret
= acpi_bus_get_device(ACPI_HANDLE(dev
), &adev
);
359 spin_lock_irqsave(&dev
->power
.lock
, flags
);
360 if (pm_runtime_suspended(dev
)) {
364 pdata
= acpi_driver_data(adev
);
365 if (WARN_ON(!pdata
|| !pdata
->mmio_base
)) {
369 *val
= __lpss_reg_read(pdata
, reg
);
372 spin_unlock_irqrestore(&dev
->power
.lock
, flags
);
376 static ssize_t
lpss_ltr_show(struct device
*dev
, struct device_attribute
*attr
,
383 reg
= strcmp(attr
->attr
.name
, "auto_ltr") ? LPSS_SW_LTR
: LPSS_AUTO_LTR
;
384 ret
= lpss_reg_read(dev
, reg
, <r_value
);
388 return snprintf(buf
, PAGE_SIZE
, "%08x\n", ltr_value
);
391 static ssize_t
lpss_ltr_mode_show(struct device
*dev
,
392 struct device_attribute
*attr
, char *buf
)
398 ret
= lpss_reg_read(dev
, LPSS_GENERAL
, <r_mode
);
402 outstr
= (ltr_mode
& LPSS_GENERAL_LTR_MODE_SW
) ? "sw" : "auto";
403 return sprintf(buf
, "%s\n", outstr
);
406 static DEVICE_ATTR(auto_ltr
, S_IRUSR
, lpss_ltr_show
, NULL
);
407 static DEVICE_ATTR(sw_ltr
, S_IRUSR
, lpss_ltr_show
, NULL
);
408 static DEVICE_ATTR(ltr_mode
, S_IRUSR
, lpss_ltr_mode_show
, NULL
);
410 static struct attribute
*lpss_attrs
[] = {
411 &dev_attr_auto_ltr
.attr
,
412 &dev_attr_sw_ltr
.attr
,
413 &dev_attr_ltr_mode
.attr
,
417 static struct attribute_group lpss_attr_group
= {
422 static void acpi_lpss_set_ltr(struct device
*dev
, s32 val
)
424 struct lpss_private_data
*pdata
= acpi_driver_data(ACPI_COMPANION(dev
));
425 u32 ltr_mode
, ltr_val
;
427 ltr_mode
= __lpss_reg_read(pdata
, LPSS_GENERAL
);
429 if (ltr_mode
& LPSS_GENERAL_LTR_MODE_SW
) {
430 ltr_mode
&= ~LPSS_GENERAL_LTR_MODE_SW
;
431 __lpss_reg_write(ltr_mode
, pdata
, LPSS_GENERAL
);
435 ltr_val
= __lpss_reg_read(pdata
, LPSS_SW_LTR
) & ~LPSS_LTR_SNOOP_MASK
;
436 if (val
>= LPSS_LTR_SNOOP_LAT_CUTOFF
) {
437 ltr_val
|= LPSS_LTR_SNOOP_LAT_32US
;
438 val
= LPSS_LTR_MAX_VAL
;
439 } else if (val
> LPSS_LTR_MAX_VAL
) {
440 ltr_val
|= LPSS_LTR_SNOOP_LAT_32US
| LPSS_LTR_SNOOP_REQ
;
441 val
>>= LPSS_LTR_SNOOP_LAT_SHIFT
;
443 ltr_val
|= LPSS_LTR_SNOOP_LAT_1US
| LPSS_LTR_SNOOP_REQ
;
446 __lpss_reg_write(ltr_val
, pdata
, LPSS_SW_LTR
);
447 if (!(ltr_mode
& LPSS_GENERAL_LTR_MODE_SW
)) {
448 ltr_mode
|= LPSS_GENERAL_LTR_MODE_SW
;
449 __lpss_reg_write(ltr_mode
, pdata
, LPSS_GENERAL
);
453 static int acpi_lpss_platform_notify(struct notifier_block
*nb
,
454 unsigned long action
, void *data
)
456 struct platform_device
*pdev
= to_platform_device(data
);
457 struct lpss_private_data
*pdata
;
458 struct acpi_device
*adev
;
459 const struct acpi_device_id
*id
;
462 id
= acpi_match_device(acpi_lpss_device_ids
, &pdev
->dev
);
463 if (!id
|| !id
->driver_data
)
466 if (acpi_bus_get_device(ACPI_HANDLE(&pdev
->dev
), &adev
))
469 pdata
= acpi_driver_data(adev
);
470 if (!pdata
|| !pdata
->mmio_base
|| !pdata
->dev_desc
->ltr_required
)
473 if (pdata
->mmio_size
< pdata
->dev_desc
->prv_offset
+ LPSS_LTR_SIZE
) {
474 dev_err(&pdev
->dev
, "MMIO size insufficient to access LTR\n");
478 if (action
== BUS_NOTIFY_ADD_DEVICE
)
479 ret
= sysfs_create_group(&pdev
->dev
.kobj
, &lpss_attr_group
);
480 else if (action
== BUS_NOTIFY_DEL_DEVICE
)
481 sysfs_remove_group(&pdev
->dev
.kobj
, &lpss_attr_group
);
486 static struct notifier_block acpi_lpss_nb
= {
487 .notifier_call
= acpi_lpss_platform_notify
,
490 static void acpi_lpss_bind(struct device
*dev
)
492 struct lpss_private_data
*pdata
= acpi_driver_data(ACPI_COMPANION(dev
));
494 if (!pdata
|| !pdata
->mmio_base
|| !pdata
->dev_desc
->ltr_required
)
497 if (pdata
->mmio_size
>= pdata
->dev_desc
->prv_offset
+ LPSS_LTR_SIZE
)
498 dev
->power
.set_latency_tolerance
= acpi_lpss_set_ltr
;
500 dev_err(dev
, "MMIO size insufficient to access LTR\n");
503 static void acpi_lpss_unbind(struct device
*dev
)
505 dev
->power
.set_latency_tolerance
= NULL
;
508 static struct acpi_scan_handler lpss_handler
= {
509 .ids
= acpi_lpss_device_ids
,
510 .attach
= acpi_lpss_create_device
,
511 .bind
= acpi_lpss_bind
,
512 .unbind
= acpi_lpss_unbind
,
515 void __init
acpi_lpss_init(void)
517 if (!lpt_clk_init()) {
518 bus_register_notifier(&platform_bus_type
, &acpi_lpss_nb
);
519 acpi_scan_add_handler(&lpss_handler
);