2 * arch/arm/mach-omap2/serial.c
4 * OMAP2 serial support.
6 * Copyright (C) 2005-2008 Nokia Corporation
7 * Author: Paul Mundt <paul.mundt@nokia.com>
9 * Major rework for PM support by Kevin Hilman
11 * Based off of arch/arm/mach-omap/omap1/serial.c
13 * Copyright (C) 2009 Texas Instruments
14 * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com
16 * This file is subject to the terms and conditions of the GNU General Public
17 * License. See the file "COPYING" in the main directory of this archive
20 #include <linux/kernel.h>
21 #include <linux/init.h>
22 #include <linux/serial_8250.h>
23 #include <linux/serial_reg.h>
24 #include <linux/clk.h>
27 #include <plat/common.h>
28 #include <plat/board.h>
29 #include <plat/clock.h>
30 #include <plat/control.h>
34 #include "prm-regbits-34xx.h"
36 #define UART_OMAP_WER 0x17 /* Wake-up enable register */
38 #define DEFAULT_TIMEOUT (5 * HZ)
40 struct omap_uart_state
{
43 struct timer_list timer
;
55 struct plat_serial8250_port
*p
;
56 struct list_head node
;
57 struct platform_device pdev
;
59 #if defined(CONFIG_ARCH_OMAP3) && defined(CONFIG_PM)
62 /* Registers to be saved/restored for OFF-mode */
72 static LIST_HEAD(uart_list
);
74 static struct plat_serial8250_port serial_platform_data0
[] = {
76 .mapbase
= OMAP_UART1_BASE
,
78 .flags
= UPF_BOOT_AUTOCONF
,
81 .uartclk
= OMAP24XX_BASE_BAUD
* 16,
87 static struct plat_serial8250_port serial_platform_data1
[] = {
89 .mapbase
= OMAP_UART2_BASE
,
91 .flags
= UPF_BOOT_AUTOCONF
,
94 .uartclk
= OMAP24XX_BASE_BAUD
* 16,
100 static struct plat_serial8250_port serial_platform_data2
[] = {
102 .mapbase
= OMAP_UART3_BASE
,
104 .flags
= UPF_BOOT_AUTOCONF
,
107 .uartclk
= OMAP24XX_BASE_BAUD
* 16,
113 #ifdef CONFIG_ARCH_OMAP4
114 static struct plat_serial8250_port serial_platform_data3
[] = {
116 .mapbase
= OMAP_UART4_BASE
,
118 .flags
= UPF_BOOT_AUTOCONF
,
121 .uartclk
= OMAP24XX_BASE_BAUD
* 16,
127 static inline unsigned int serial_read_reg(struct plat_serial8250_port
*up
,
130 offset
<<= up
->regshift
;
131 return (unsigned int)__raw_readb(up
->membase
+ offset
);
134 static inline void serial_write_reg(struct plat_serial8250_port
*p
, int offset
,
137 offset
<<= p
->regshift
;
138 __raw_writeb(value
, p
->membase
+ offset
);
142 * Internal UARTs need to be initialized for the 8250 autoconfig to work
143 * properly. Note that the TX watermark initialization may not be needed
144 * once the 8250.c watermark handling code is merged.
146 static inline void __init
omap_uart_reset(struct omap_uart_state
*uart
)
148 struct plat_serial8250_port
*p
= uart
->p
;
150 serial_write_reg(p
, UART_OMAP_MDR1
, 0x07);
151 serial_write_reg(p
, UART_OMAP_SCR
, 0x08);
152 serial_write_reg(p
, UART_OMAP_MDR1
, 0x00);
153 serial_write_reg(p
, UART_OMAP_SYSC
, (0x02 << 3) | (1 << 2) | (1 << 0));
156 #if defined(CONFIG_PM) && defined(CONFIG_ARCH_OMAP3)
158 static void omap_uart_save_context(struct omap_uart_state
*uart
)
161 struct plat_serial8250_port
*p
= uart
->p
;
163 if (!enable_off_mode
)
166 lcr
= serial_read_reg(p
, UART_LCR
);
167 serial_write_reg(p
, UART_LCR
, 0xBF);
168 uart
->dll
= serial_read_reg(p
, UART_DLL
);
169 uart
->dlh
= serial_read_reg(p
, UART_DLM
);
170 serial_write_reg(p
, UART_LCR
, lcr
);
171 uart
->ier
= serial_read_reg(p
, UART_IER
);
172 uart
->sysc
= serial_read_reg(p
, UART_OMAP_SYSC
);
173 uart
->scr
= serial_read_reg(p
, UART_OMAP_SCR
);
174 uart
->wer
= serial_read_reg(p
, UART_OMAP_WER
);
176 uart
->context_valid
= 1;
179 static void omap_uart_restore_context(struct omap_uart_state
*uart
)
182 struct plat_serial8250_port
*p
= uart
->p
;
184 if (!enable_off_mode
)
187 if (!uart
->context_valid
)
190 uart
->context_valid
= 0;
192 serial_write_reg(p
, UART_OMAP_MDR1
, 0x7);
193 serial_write_reg(p
, UART_LCR
, 0xBF); /* Config B mode */
194 efr
= serial_read_reg(p
, UART_EFR
);
195 serial_write_reg(p
, UART_EFR
, UART_EFR_ECB
);
196 serial_write_reg(p
, UART_LCR
, 0x0); /* Operational mode */
197 serial_write_reg(p
, UART_IER
, 0x0);
198 serial_write_reg(p
, UART_LCR
, 0xBF); /* Config B mode */
199 serial_write_reg(p
, UART_DLL
, uart
->dll
);
200 serial_write_reg(p
, UART_DLM
, uart
->dlh
);
201 serial_write_reg(p
, UART_LCR
, 0x0); /* Operational mode */
202 serial_write_reg(p
, UART_IER
, uart
->ier
);
203 serial_write_reg(p
, UART_FCR
, 0xA1);
204 serial_write_reg(p
, UART_LCR
, 0xBF); /* Config B mode */
205 serial_write_reg(p
, UART_EFR
, efr
);
206 serial_write_reg(p
, UART_LCR
, UART_LCR_WLEN8
);
207 serial_write_reg(p
, UART_OMAP_SCR
, uart
->scr
);
208 serial_write_reg(p
, UART_OMAP_WER
, uart
->wer
);
209 serial_write_reg(p
, UART_OMAP_SYSC
, uart
->sysc
);
210 serial_write_reg(p
, UART_OMAP_MDR1
, 0x00); /* UART 16x mode */
213 static inline void omap_uart_save_context(struct omap_uart_state
*uart
) {}
214 static inline void omap_uart_restore_context(struct omap_uart_state
*uart
) {}
215 #endif /* CONFIG_PM && CONFIG_ARCH_OMAP3 */
217 static inline void omap_uart_enable_clocks(struct omap_uart_state
*uart
)
222 clk_enable(uart
->ick
);
223 clk_enable(uart
->fck
);
225 omap_uart_restore_context(uart
);
230 static inline void omap_uart_disable_clocks(struct omap_uart_state
*uart
)
235 omap_uart_save_context(uart
);
237 clk_disable(uart
->ick
);
238 clk_disable(uart
->fck
);
241 static void omap_uart_enable_wakeup(struct omap_uart_state
*uart
)
243 /* Set wake-enable bit */
244 if (uart
->wk_en
&& uart
->wk_mask
) {
245 u32 v
= __raw_readl(uart
->wk_en
);
247 __raw_writel(v
, uart
->wk_en
);
250 /* Ensure IOPAD wake-enables are set */
251 if (cpu_is_omap34xx() && uart
->padconf
) {
252 u16 v
= omap_ctrl_readw(uart
->padconf
);
253 v
|= OMAP3_PADCONF_WAKEUPENABLE0
;
254 omap_ctrl_writew(v
, uart
->padconf
);
258 static void omap_uart_disable_wakeup(struct omap_uart_state
*uart
)
260 /* Clear wake-enable bit */
261 if (uart
->wk_en
&& uart
->wk_mask
) {
262 u32 v
= __raw_readl(uart
->wk_en
);
264 __raw_writel(v
, uart
->wk_en
);
267 /* Ensure IOPAD wake-enables are cleared */
268 if (cpu_is_omap34xx() && uart
->padconf
) {
269 u16 v
= omap_ctrl_readw(uart
->padconf
);
270 v
&= ~OMAP3_PADCONF_WAKEUPENABLE0
;
271 omap_ctrl_writew(v
, uart
->padconf
);
275 static void omap_uart_smart_idle_enable(struct omap_uart_state
*uart
,
278 struct plat_serial8250_port
*p
= uart
->p
;
281 sysc
= serial_read_reg(p
, UART_OMAP_SYSC
) & 0x7;
287 serial_write_reg(p
, UART_OMAP_SYSC
, sysc
);
290 static void omap_uart_block_sleep(struct omap_uart_state
*uart
)
292 omap_uart_enable_clocks(uart
);
294 omap_uart_smart_idle_enable(uart
, 0);
297 mod_timer(&uart
->timer
, jiffies
+ uart
->timeout
);
299 del_timer(&uart
->timer
);
302 static void omap_uart_allow_sleep(struct omap_uart_state
*uart
)
304 if (device_may_wakeup(&uart
->pdev
.dev
))
305 omap_uart_enable_wakeup(uart
);
307 omap_uart_disable_wakeup(uart
);
312 omap_uart_smart_idle_enable(uart
, 1);
314 del_timer(&uart
->timer
);
317 static void omap_uart_idle_timer(unsigned long data
)
319 struct omap_uart_state
*uart
= (struct omap_uart_state
*)data
;
321 omap_uart_allow_sleep(uart
);
324 void omap_uart_prepare_idle(int num
)
326 struct omap_uart_state
*uart
;
328 list_for_each_entry(uart
, &uart_list
, node
) {
329 if (num
== uart
->num
&& uart
->can_sleep
) {
330 omap_uart_disable_clocks(uart
);
336 void omap_uart_resume_idle(int num
)
338 struct omap_uart_state
*uart
;
340 list_for_each_entry(uart
, &uart_list
, node
) {
341 if (num
== uart
->num
) {
342 omap_uart_enable_clocks(uart
);
344 /* Check for IO pad wakeup */
345 if (cpu_is_omap34xx() && uart
->padconf
) {
346 u16 p
= omap_ctrl_readw(uart
->padconf
);
348 if (p
& OMAP3_PADCONF_WAKEUPEVENT0
)
349 omap_uart_block_sleep(uart
);
352 /* Check for normal UART wakeup */
353 if (__raw_readl(uart
->wk_st
) & uart
->wk_mask
)
354 omap_uart_block_sleep(uart
);
360 void omap_uart_prepare_suspend(void)
362 struct omap_uart_state
*uart
;
364 list_for_each_entry(uart
, &uart_list
, node
) {
365 omap_uart_allow_sleep(uart
);
369 int omap_uart_can_sleep(void)
371 struct omap_uart_state
*uart
;
374 list_for_each_entry(uart
, &uart_list
, node
) {
378 if (!uart
->can_sleep
) {
383 /* This UART can now safely sleep. */
384 omap_uart_allow_sleep(uart
);
391 * omap_uart_interrupt()
393 * This handler is used only to detect that *any* UART interrupt has
394 * occurred. It does _nothing_ to handle the interrupt. Rather,
395 * any UART interrupt will trigger the inactivity timer so the
396 * UART will not idle or sleep for its timeout period.
399 static irqreturn_t
omap_uart_interrupt(int irq
, void *dev_id
)
401 struct omap_uart_state
*uart
= dev_id
;
403 omap_uart_block_sleep(uart
);
408 static void omap_uart_idle_init(struct omap_uart_state
*uart
)
410 struct plat_serial8250_port
*p
= uart
->p
;
414 uart
->timeout
= DEFAULT_TIMEOUT
;
415 setup_timer(&uart
->timer
, omap_uart_idle_timer
,
416 (unsigned long) uart
);
417 mod_timer(&uart
->timer
, jiffies
+ uart
->timeout
);
418 omap_uart_smart_idle_enable(uart
, 0);
420 if (cpu_is_omap34xx()) {
421 u32 mod
= (uart
->num
== 2) ? OMAP3430_PER_MOD
: CORE_MOD
;
425 uart
->wk_en
= OMAP34XX_PRM_REGADDR(mod
, PM_WKEN1
);
426 uart
->wk_st
= OMAP34XX_PRM_REGADDR(mod
, PM_WKST1
);
429 wk_mask
= OMAP3430_ST_UART1_MASK
;
433 wk_mask
= OMAP3430_ST_UART2_MASK
;
437 wk_mask
= OMAP3430_ST_UART3_MASK
;
441 uart
->wk_mask
= wk_mask
;
442 uart
->padconf
= padconf
;
443 } else if (cpu_is_omap24xx()) {
446 if (cpu_is_omap2430()) {
447 uart
->wk_en
= OMAP2430_PRM_REGADDR(CORE_MOD
, PM_WKEN1
);
448 uart
->wk_st
= OMAP2430_PRM_REGADDR(CORE_MOD
, PM_WKST1
);
449 } else if (cpu_is_omap2420()) {
450 uart
->wk_en
= OMAP2420_PRM_REGADDR(CORE_MOD
, PM_WKEN1
);
451 uart
->wk_st
= OMAP2420_PRM_REGADDR(CORE_MOD
, PM_WKST1
);
455 wk_mask
= OMAP24XX_ST_UART1_MASK
;
458 wk_mask
= OMAP24XX_ST_UART2_MASK
;
461 wk_mask
= OMAP24XX_ST_UART3_MASK
;
464 uart
->wk_mask
= wk_mask
;
472 p
->irqflags
|= IRQF_SHARED
;
473 ret
= request_irq(p
->irq
, omap_uart_interrupt
, IRQF_SHARED
,
474 "serial idle", (void *)uart
);
478 void omap_uart_enable_irqs(int enable
)
481 struct omap_uart_state
*uart
;
483 list_for_each_entry(uart
, &uart_list
, node
) {
485 ret
= request_irq(uart
->p
->irq
, omap_uart_interrupt
,
486 IRQF_SHARED
, "serial idle", (void *)uart
);
488 free_irq(uart
->p
->irq
, (void *)uart
);
492 static ssize_t
sleep_timeout_show(struct device
*dev
,
493 struct device_attribute
*attr
,
496 struct platform_device
*pdev
= container_of(dev
,
497 struct platform_device
, dev
);
498 struct omap_uart_state
*uart
= container_of(pdev
,
499 struct omap_uart_state
, pdev
);
501 return sprintf(buf
, "%u\n", uart
->timeout
/ HZ
);
504 static ssize_t
sleep_timeout_store(struct device
*dev
,
505 struct device_attribute
*attr
,
506 const char *buf
, size_t n
)
508 struct platform_device
*pdev
= container_of(dev
,
509 struct platform_device
, dev
);
510 struct omap_uart_state
*uart
= container_of(pdev
,
511 struct omap_uart_state
, pdev
);
514 if (sscanf(buf
, "%u", &value
) != 1) {
515 printk(KERN_ERR
"sleep_timeout_store: Invalid value\n");
519 uart
->timeout
= value
* HZ
;
521 mod_timer(&uart
->timer
, jiffies
+ uart
->timeout
);
523 /* A zero value means disable timeout feature */
524 omap_uart_block_sleep(uart
);
529 DEVICE_ATTR(sleep_timeout
, 0644, sleep_timeout_show
, sleep_timeout_store
);
530 #define DEV_CREATE_FILE(dev, attr) WARN_ON(device_create_file(dev, attr))
532 static inline void omap_uart_idle_init(struct omap_uart_state
*uart
) {}
533 #define DEV_CREATE_FILE(dev, attr)
534 #endif /* CONFIG_PM */
536 static struct omap_uart_state omap_uart
[] = {
539 .name
= "serial8250",
540 .id
= PLAT8250_DEV_PLATFORM
,
542 .platform_data
= serial_platform_data0
,
547 .name
= "serial8250",
548 .id
= PLAT8250_DEV_PLATFORM1
,
550 .platform_data
= serial_platform_data1
,
555 .name
= "serial8250",
556 .id
= PLAT8250_DEV_PLATFORM2
,
558 .platform_data
= serial_platform_data2
,
562 #ifdef CONFIG_ARCH_OMAP4
565 .name
= "serial8250",
568 .platform_data
= serial_platform_data3
,
575 void __init
omap_serial_early_init(void)
581 * Make sure the serial ports are muxed on at this point.
582 * You have to mux them off in device drivers later on
586 for (i
= 0; i
< ARRAY_SIZE(omap_uart
); i
++) {
587 struct omap_uart_state
*uart
= &omap_uart
[i
];
588 struct platform_device
*pdev
= &uart
->pdev
;
589 struct device
*dev
= &pdev
->dev
;
590 struct plat_serial8250_port
*p
= dev
->platform_data
;
593 * Module 4KB + L4 interconnect 4KB
594 * Static mapping, never released
596 p
->membase
= ioremap(p
->mapbase
, SZ_8K
);
598 printk(KERN_ERR
"ioremap failed for uart%i\n", i
+ 1);
602 sprintf(name
, "uart%d_ick", i
+1);
603 uart
->ick
= clk_get(NULL
, name
);
604 if (IS_ERR(uart
->ick
)) {
605 printk(KERN_ERR
"Could not get uart%d_ick\n", i
+1);
609 sprintf(name
, "uart%d_fck", i
+1);
610 uart
->fck
= clk_get(NULL
, name
);
611 if (IS_ERR(uart
->fck
)) {
612 printk(KERN_ERR
"Could not get uart%d_fck\n", i
+1);
616 /* FIXME: Remove this once the clkdev is ready */
617 if (!cpu_is_omap44xx()) {
618 if (!uart
->ick
|| !uart
->fck
)
623 p
->private_data
= uart
;
625 list_add_tail(&uart
->node
, &uart_list
);
627 if (cpu_is_omap44xx())
630 omap_uart_enable_clocks(uart
);
634 void __init
omap_serial_init(void)
638 for (i
= 0; i
< ARRAY_SIZE(omap_uart
); i
++) {
639 struct omap_uart_state
*uart
= &omap_uart
[i
];
640 struct platform_device
*pdev
= &uart
->pdev
;
641 struct device
*dev
= &pdev
->dev
;
643 omap_uart_reset(uart
);
644 omap_uart_idle_init(uart
);
646 if (WARN_ON(platform_device_register(pdev
)))
648 if ((cpu_is_omap34xx() && uart
->padconf
) ||
649 (uart
->wk_en
&& uart
->wk_mask
)) {
650 device_init_wakeup(dev
, true);
651 DEV_CREATE_FILE(dev
, &dev_attr_sleep_timeout
);