1 /* linux/arch/arm/mach-s3c2412/clock.c
3 * Copyright (c) 2006 Simtec Electronics
4 * Ben Dooks <ben@simtec.co.uk>
6 * S3C2412,S3C2413 Clock control support
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 #include <linux/init.h>
24 #include <linux/module.h>
25 #include <linux/kernel.h>
26 #include <linux/list.h>
27 #include <linux/errno.h>
28 #include <linux/err.h>
29 #include <linux/device.h>
30 #include <linux/clk.h>
31 #include <linux/mutex.h>
32 #include <linux/delay.h>
33 #include <linux/serial_core.h>
36 #include <asm/mach/map.h>
38 #include <mach/hardware.h>
40 #include <plat/regs-serial.h>
41 #include <mach/regs-clock.h>
42 #include <mach/regs-gpio.h>
44 #include <plat/clock.h>
47 /* We currently have to assume that the system is running
48 * from the XTPll input, and that all ***REFCLKs are being
49 * fed from it, as we cannot read the state of OM[4] from
52 * It would be possible for each board initialisation to
53 * set the correct muxing at initialisation
56 static int s3c2412_clkcon_enable(struct clk
*clk
, int enable
)
58 unsigned int clocks
= clk
->ctrlbit
;
61 clkcon
= __raw_readl(S3C2410_CLKCON
);
68 __raw_writel(clkcon
, S3C2410_CLKCON
);
73 static int s3c2412_upll_enable(struct clk
*clk
, int enable
)
75 unsigned long upllcon
= __raw_readl(S3C2410_UPLLCON
);
76 unsigned long orig
= upllcon
;
79 upllcon
|= S3C2412_PLLCON_OFF
;
81 upllcon
&= ~S3C2412_PLLCON_OFF
;
83 __raw_writel(upllcon
, S3C2410_UPLLCON
);
85 /* allow ~150uS for the PLL to settle and lock */
87 if (enable
&& (orig
& S3C2412_PLLCON_OFF
))
93 /* clock selections */
95 static struct clk clk_erefclk
= {
99 static struct clk clk_urefclk
= {
103 static int s3c2412_setparent_usysclk(struct clk
*clk
, struct clk
*parent
)
105 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
107 if (parent
== &clk_urefclk
)
108 clksrc
&= ~S3C2412_CLKSRC_USYSCLK_UPLL
;
109 else if (parent
== &clk_upll
)
110 clksrc
|= S3C2412_CLKSRC_USYSCLK_UPLL
;
114 clk
->parent
= parent
;
116 __raw_writel(clksrc
, S3C2412_CLKSRC
);
120 static struct clk clk_usysclk
= {
123 .ops
= &(struct clk_ops
) {
124 .set_parent
= s3c2412_setparent_usysclk
,
128 static struct clk clk_mrefclk
= {
133 static struct clk clk_mdivclk
= {
138 static int s3c2412_setparent_usbsrc(struct clk
*clk
, struct clk
*parent
)
140 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
142 if (parent
== &clk_usysclk
)
143 clksrc
&= ~S3C2412_CLKSRC_USBCLK_HCLK
;
144 else if (parent
== &clk_h
)
145 clksrc
|= S3C2412_CLKSRC_USBCLK_HCLK
;
149 clk
->parent
= parent
;
151 __raw_writel(clksrc
, S3C2412_CLKSRC
);
155 static unsigned long s3c2412_roundrate_usbsrc(struct clk
*clk
,
158 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
161 if (rate
> parent_rate
)
164 div
= parent_rate
/ rate
;
168 return parent_rate
/ div
;
171 static unsigned long s3c2412_getrate_usbsrc(struct clk
*clk
)
173 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
174 unsigned long div
= __raw_readl(S3C2410_CLKDIVN
);
176 return parent_rate
/ ((div
& S3C2412_CLKDIVN_USB48DIV
) ? 2 : 1);
179 static int s3c2412_setrate_usbsrc(struct clk
*clk
, unsigned long rate
)
181 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
182 unsigned long clkdivn
= __raw_readl(S3C2410_CLKDIVN
);
184 rate
= s3c2412_roundrate_usbsrc(clk
, rate
);
186 if ((parent_rate
/ rate
) == 2)
187 clkdivn
|= S3C2412_CLKDIVN_USB48DIV
;
189 clkdivn
&= ~S3C2412_CLKDIVN_USB48DIV
;
191 __raw_writel(clkdivn
, S3C2410_CLKDIVN
);
195 static struct clk clk_usbsrc
= {
197 .ops
= &(struct clk_ops
) {
198 .get_rate
= s3c2412_getrate_usbsrc
,
199 .set_rate
= s3c2412_setrate_usbsrc
,
200 .round_rate
= s3c2412_roundrate_usbsrc
,
201 .set_parent
= s3c2412_setparent_usbsrc
,
205 static int s3c2412_setparent_msysclk(struct clk
*clk
, struct clk
*parent
)
207 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
209 if (parent
== &clk_mdivclk
)
210 clksrc
&= ~S3C2412_CLKSRC_MSYSCLK_MPLL
;
211 else if (parent
== &clk_mpll
)
212 clksrc
|= S3C2412_CLKSRC_MSYSCLK_MPLL
;
216 clk
->parent
= parent
;
218 __raw_writel(clksrc
, S3C2412_CLKSRC
);
222 static struct clk clk_msysclk
= {
224 .ops
= &(struct clk_ops
) {
225 .set_parent
= s3c2412_setparent_msysclk
,
229 static int s3c2412_setparent_armclk(struct clk
*clk
, struct clk
*parent
)
232 unsigned long clkdiv
;
235 /* Note, we current equate fclk andf msysclk for S3C2412 */
237 if (parent
== &clk_msysclk
|| parent
== &clk_f
)
239 else if (parent
== &clk_h
)
240 dvs
= S3C2412_CLKDIVN_DVSEN
;
244 clk
->parent
= parent
;
246 /* update this under irq lockdown, clkdivn is not protected
247 * by the clock system. */
249 local_irq_save(flags
);
251 clkdiv
= __raw_readl(S3C2410_CLKDIVN
);
252 clkdiv
&= ~S3C2412_CLKDIVN_DVSEN
;
254 __raw_writel(clkdiv
, S3C2410_CLKDIVN
);
256 local_irq_restore(flags
);
261 static struct clk clk_armclk
= {
263 .parent
= &clk_msysclk
,
264 .ops
= &(struct clk_ops
) {
265 .set_parent
= s3c2412_setparent_armclk
,
269 /* these next clocks have an divider immediately after them,
270 * so we can register them with their divider and leave out the
271 * intermediate clock stage
273 static unsigned long s3c2412_roundrate_clksrc(struct clk
*clk
,
276 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
279 if (rate
> parent_rate
)
282 /* note, we remove the +/- 1 calculations as they cancel out */
284 div
= (rate
/ parent_rate
);
291 return parent_rate
/ div
;
294 static int s3c2412_setparent_uart(struct clk
*clk
, struct clk
*parent
)
296 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
298 if (parent
== &clk_erefclk
)
299 clksrc
&= ~S3C2412_CLKSRC_UARTCLK_MPLL
;
300 else if (parent
== &clk_mpll
)
301 clksrc
|= S3C2412_CLKSRC_UARTCLK_MPLL
;
305 clk
->parent
= parent
;
307 __raw_writel(clksrc
, S3C2412_CLKSRC
);
311 static unsigned long s3c2412_getrate_uart(struct clk
*clk
)
313 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
314 unsigned long div
= __raw_readl(S3C2410_CLKDIVN
);
316 div
&= S3C2412_CLKDIVN_UARTDIV_MASK
;
317 div
>>= S3C2412_CLKDIVN_UARTDIV_SHIFT
;
319 return parent_rate
/ (div
+ 1);
322 static int s3c2412_setrate_uart(struct clk
*clk
, unsigned long rate
)
324 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
325 unsigned long clkdivn
= __raw_readl(S3C2410_CLKDIVN
);
327 rate
= s3c2412_roundrate_clksrc(clk
, rate
);
329 clkdivn
&= ~S3C2412_CLKDIVN_UARTDIV_MASK
;
330 clkdivn
|= ((parent_rate
/ rate
) - 1) << S3C2412_CLKDIVN_UARTDIV_SHIFT
;
332 __raw_writel(clkdivn
, S3C2410_CLKDIVN
);
336 static struct clk clk_uart
= {
338 .ops
= &(struct clk_ops
) {
339 .get_rate
= s3c2412_getrate_uart
,
340 .set_rate
= s3c2412_setrate_uart
,
341 .set_parent
= s3c2412_setparent_uart
,
342 .round_rate
= s3c2412_roundrate_clksrc
,
346 static int s3c2412_setparent_i2s(struct clk
*clk
, struct clk
*parent
)
348 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
350 if (parent
== &clk_erefclk
)
351 clksrc
&= ~S3C2412_CLKSRC_I2SCLK_MPLL
;
352 else if (parent
== &clk_mpll
)
353 clksrc
|= S3C2412_CLKSRC_I2SCLK_MPLL
;
357 clk
->parent
= parent
;
359 __raw_writel(clksrc
, S3C2412_CLKSRC
);
363 static unsigned long s3c2412_getrate_i2s(struct clk
*clk
)
365 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
366 unsigned long div
= __raw_readl(S3C2410_CLKDIVN
);
368 div
&= S3C2412_CLKDIVN_I2SDIV_MASK
;
369 div
>>= S3C2412_CLKDIVN_I2SDIV_SHIFT
;
371 return parent_rate
/ (div
+ 1);
374 static int s3c2412_setrate_i2s(struct clk
*clk
, unsigned long rate
)
376 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
377 unsigned long clkdivn
= __raw_readl(S3C2410_CLKDIVN
);
379 rate
= s3c2412_roundrate_clksrc(clk
, rate
);
381 clkdivn
&= ~S3C2412_CLKDIVN_I2SDIV_MASK
;
382 clkdivn
|= ((parent_rate
/ rate
) - 1) << S3C2412_CLKDIVN_I2SDIV_SHIFT
;
384 __raw_writel(clkdivn
, S3C2410_CLKDIVN
);
388 static struct clk clk_i2s
= {
390 .ops
= &(struct clk_ops
) {
391 .get_rate
= s3c2412_getrate_i2s
,
392 .set_rate
= s3c2412_setrate_i2s
,
393 .set_parent
= s3c2412_setparent_i2s
,
394 .round_rate
= s3c2412_roundrate_clksrc
,
398 static int s3c2412_setparent_cam(struct clk
*clk
, struct clk
*parent
)
400 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
402 if (parent
== &clk_usysclk
)
403 clksrc
&= ~S3C2412_CLKSRC_CAMCLK_HCLK
;
404 else if (parent
== &clk_h
)
405 clksrc
|= S3C2412_CLKSRC_CAMCLK_HCLK
;
409 clk
->parent
= parent
;
411 __raw_writel(clksrc
, S3C2412_CLKSRC
);
414 static unsigned long s3c2412_getrate_cam(struct clk
*clk
)
416 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
417 unsigned long div
= __raw_readl(S3C2410_CLKDIVN
);
419 div
&= S3C2412_CLKDIVN_CAMDIV_MASK
;
420 div
>>= S3C2412_CLKDIVN_CAMDIV_SHIFT
;
422 return parent_rate
/ (div
+ 1);
425 static int s3c2412_setrate_cam(struct clk
*clk
, unsigned long rate
)
427 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
428 unsigned long clkdivn
= __raw_readl(S3C2410_CLKDIVN
);
430 rate
= s3c2412_roundrate_clksrc(clk
, rate
);
432 clkdivn
&= ~S3C2412_CLKDIVN_CAMDIV_MASK
;
433 clkdivn
|= ((parent_rate
/ rate
) - 1) << S3C2412_CLKDIVN_CAMDIV_SHIFT
;
435 __raw_writel(clkdivn
, S3C2410_CLKDIVN
);
439 static struct clk clk_cam
= {
440 .name
= "camif-upll", /* same as 2440 name */
441 .ops
= &(struct clk_ops
) {
442 .get_rate
= s3c2412_getrate_cam
,
443 .set_rate
= s3c2412_setrate_cam
,
444 .set_parent
= s3c2412_setparent_cam
,
445 .round_rate
= s3c2412_roundrate_clksrc
,
449 /* standard clock definitions */
451 static struct clk init_clocks_disable
[] = {
455 .enable
= s3c2412_clkcon_enable
,
456 .ctrlbit
= S3C2412_CLKCON_NAND
,
460 .enable
= s3c2412_clkcon_enable
,
461 .ctrlbit
= S3C2412_CLKCON_SDI
,
465 .enable
= s3c2412_clkcon_enable
,
466 .ctrlbit
= S3C2412_CLKCON_ADC
,
470 .enable
= s3c2412_clkcon_enable
,
471 .ctrlbit
= S3C2412_CLKCON_IIC
,
475 .enable
= s3c2412_clkcon_enable
,
476 .ctrlbit
= S3C2412_CLKCON_IIS
,
480 .enable
= s3c2412_clkcon_enable
,
481 .ctrlbit
= S3C2412_CLKCON_SPI
,
485 static struct clk init_clocks
[] = {
489 .enable
= s3c2412_clkcon_enable
,
490 .ctrlbit
= S3C2412_CLKCON_DMA0
,
494 .enable
= s3c2412_clkcon_enable
,
495 .ctrlbit
= S3C2412_CLKCON_DMA1
,
499 .enable
= s3c2412_clkcon_enable
,
500 .ctrlbit
= S3C2412_CLKCON_DMA2
,
504 .enable
= s3c2412_clkcon_enable
,
505 .ctrlbit
= S3C2412_CLKCON_DMA3
,
509 .enable
= s3c2412_clkcon_enable
,
510 .ctrlbit
= S3C2412_CLKCON_LCDC
,
514 .enable
= s3c2412_clkcon_enable
,
515 .ctrlbit
= S3C2412_CLKCON_GPIO
,
519 .enable
= s3c2412_clkcon_enable
,
520 .ctrlbit
= S3C2412_CLKCON_USBH
,
522 .name
= "usb-device",
524 .enable
= s3c2412_clkcon_enable
,
525 .ctrlbit
= S3C2412_CLKCON_USBD
,
529 .enable
= s3c2412_clkcon_enable
,
530 .ctrlbit
= S3C2412_CLKCON_PWMT
,
533 .devname
= "s3c2412-uart.0",
535 .enable
= s3c2412_clkcon_enable
,
536 .ctrlbit
= S3C2412_CLKCON_UART0
,
539 .devname
= "s3c2412-uart.1",
541 .enable
= s3c2412_clkcon_enable
,
542 .ctrlbit
= S3C2412_CLKCON_UART1
,
545 .devname
= "s3c2412-uart.2",
547 .enable
= s3c2412_clkcon_enable
,
548 .ctrlbit
= S3C2412_CLKCON_UART2
,
552 .enable
= s3c2412_clkcon_enable
,
553 .ctrlbit
= S3C2412_CLKCON_RTC
,
559 .name
= "usb-bus-gadget",
560 .parent
= &clk_usb_bus
,
561 .enable
= s3c2412_clkcon_enable
,
562 .ctrlbit
= S3C2412_CLKCON_USB_DEV48
,
564 .name
= "usb-bus-host",
565 .parent
= &clk_usb_bus
,
566 .enable
= s3c2412_clkcon_enable
,
567 .ctrlbit
= S3C2412_CLKCON_USB_HOST48
,
571 /* clocks to add where we need to check their parentage */
580 static struct clk_init clks_src
[] __initdata
= {
583 .bit
= S3C2412_CLKSRC_USBCLK_HCLK
,
584 .src_0
= &clk_urefclk
,
588 .bit
= S3C2412_CLKSRC_I2SCLK_MPLL
,
589 .src_0
= &clk_erefclk
,
593 .bit
= S3C2412_CLKSRC_CAMCLK_HCLK
,
594 .src_0
= &clk_usysclk
,
598 .bit
= S3C2412_CLKSRC_MSYSCLK_MPLL
,
599 .src_0
= &clk_mdivclk
,
603 .bit
= S3C2412_CLKSRC_UARTCLK_MPLL
,
604 .src_0
= &clk_erefclk
,
608 .bit
= S3C2412_CLKSRC_USBCLK_HCLK
,
609 .src_0
= &clk_usysclk
,
611 /* here we assume OM[4] select xtal */
614 .bit
= S3C2412_CLKSRC_EREFCLK_EXTCLK
,
619 .bit
= S3C2412_CLKSRC_UREFCLK_EXTCLK
,
625 /* s3c2412_clk_initparents
627 * Initialise the parents for the clocks that we get at start-time
630 static void __init
s3c2412_clk_initparents(void)
632 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
633 struct clk_init
*cip
= clks_src
;
638 for (ptr
= 0; ptr
< ARRAY_SIZE(clks_src
); ptr
++, cip
++) {
639 ret
= s3c24xx_register_clock(cip
->clk
);
641 printk(KERN_ERR
"Failed to register clock %s (%d)\n",
642 cip
->clk
->name
, ret
);
645 src
= (clksrc
& cip
->bit
) ? cip
->src_1
: cip
->src_0
;
647 printk(KERN_INFO
"%s: parent %s\n", cip
->clk
->name
, src
->name
);
648 clk_set_parent(cip
->clk
, src
);
652 /* clocks to add straight away */
654 static struct clk
*clks
[] __initdata
= {
661 static struct clk_lookup s3c2412_clk_lookup
[] = {
662 CLKDEV_INIT(NULL
, "clk_uart_baud1", &s3c24xx_uclk
),
663 CLKDEV_INIT(NULL
, "clk_uart_baud2", &clk_p
),
664 CLKDEV_INIT(NULL
, "clk_uart_baud3", &clk_usysclk
),
667 int __init
s3c2412_baseclk_add(void)
669 unsigned long clkcon
= __raw_readl(S3C2410_CLKCON
);
675 clk_upll
.enable
= s3c2412_upll_enable
;
676 clk_usb_bus
.parent
= &clk_usbsrc
;
677 clk_usb_bus
.rate
= 0x0;
679 clk_f
.parent
= &clk_msysclk
;
681 s3c2412_clk_initparents();
683 for (ptr
= 0; ptr
< ARRAY_SIZE(clks
); ptr
++) {
686 ret
= s3c24xx_register_clock(clkp
);
688 printk(KERN_ERR
"Failed to register clock %s (%d)\n",
693 /* set the dvs state according to what we got at boot time */
695 dvs
= __raw_readl(S3C2410_CLKDIVN
) & S3C2412_CLKDIVN_DVSEN
;
698 clk_armclk
.parent
= &clk_h
;
700 printk(KERN_INFO
"S3C2412: DVS is %s\n", dvs
? "on" : "off");
702 /* ensure usb bus clock is within correct rate of 48MHz */
704 if (clk_get_rate(&clk_usb_bus
) != (48 * 1000 * 1000)) {
705 printk(KERN_INFO
"Warning: USB bus clock not at 48MHz\n");
707 /* for the moment, let's use the UPLL, and see if we can
710 clk_set_parent(&clk_usysclk
, &clk_upll
);
711 clk_set_parent(&clk_usbsrc
, &clk_usysclk
);
712 clk_set_rate(&clk_usbsrc
, 48*1000*1000);
715 printk("S3C2412: upll %s, %ld.%03ld MHz, usb-bus %ld.%03ld MHz\n",
716 (__raw_readl(S3C2410_UPLLCON
) & S3C2412_PLLCON_OFF
) ? "off":"on",
717 print_mhz(clk_get_rate(&clk_upll
)),
718 print_mhz(clk_get_rate(&clk_usb_bus
)));
720 /* register clocks from clock array */
723 for (ptr
= 0; ptr
< ARRAY_SIZE(init_clocks
); ptr
++, clkp
++) {
724 /* ensure that we note the clock state */
726 clkp
->usage
= clkcon
& clkp
->ctrlbit
? 1 : 0;
728 ret
= s3c24xx_register_clock(clkp
);
730 printk(KERN_ERR
"Failed to register clock %s (%d)\n",
735 /* We must be careful disabling the clocks we are not intending to
736 * be using at boot time, as subsystems such as the LCD which do
737 * their own DMA requests to the bus can cause the system to lockup
738 * if they where in the middle of requesting bus access.
740 * Disabling the LCD clock if the LCD is active is very dangerous,
741 * and therefore the bootloader should be careful to not enable
742 * the LCD clock if it is not needed.
745 /* install (and disable) the clocks we do not need immediately */
747 clkp
= init_clocks_disable
;
748 for (ptr
= 0; ptr
< ARRAY_SIZE(init_clocks_disable
); ptr
++, clkp
++) {
750 ret
= s3c24xx_register_clock(clkp
);
752 printk(KERN_ERR
"Failed to register clock %s (%d)\n",
756 s3c2412_clkcon_enable(clkp
, 0);
759 clkdev_add_table(s3c2412_clk_lookup
, ARRAY_SIZE(s3c2412_clk_lookup
));