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/sysdev.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/s3c2412.h>
45 #include <plat/clock.h>
48 /* We currently have to assume that the system is running
49 * from the XTPll input, and that all ***REFCLKs are being
50 * fed from it, as we cannot read the state of OM[4] from
53 * It would be possible for each board initialisation to
54 * set the correct muxing at initialisation
57 static int s3c2412_clkcon_enable(struct clk
*clk
, int enable
)
59 unsigned int clocks
= clk
->ctrlbit
;
62 clkcon
= __raw_readl(S3C2410_CLKCON
);
69 __raw_writel(clkcon
, S3C2410_CLKCON
);
74 static int s3c2412_upll_enable(struct clk
*clk
, int enable
)
76 unsigned long upllcon
= __raw_readl(S3C2410_UPLLCON
);
77 unsigned long orig
= upllcon
;
80 upllcon
|= S3C2412_PLLCON_OFF
;
82 upllcon
&= ~S3C2412_PLLCON_OFF
;
84 __raw_writel(upllcon
, S3C2410_UPLLCON
);
86 /* allow ~150uS for the PLL to settle and lock */
88 if (enable
&& (orig
& S3C2412_PLLCON_OFF
))
94 /* clock selections */
96 static struct clk clk_erefclk
= {
100 static struct clk clk_urefclk
= {
104 static int s3c2412_setparent_usysclk(struct clk
*clk
, struct clk
*parent
)
106 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
108 if (parent
== &clk_urefclk
)
109 clksrc
&= ~S3C2412_CLKSRC_USYSCLK_UPLL
;
110 else if (parent
== &clk_upll
)
111 clksrc
|= S3C2412_CLKSRC_USYSCLK_UPLL
;
115 clk
->parent
= parent
;
117 __raw_writel(clksrc
, S3C2412_CLKSRC
);
121 static struct clk clk_usysclk
= {
124 .ops
= &(struct clk_ops
) {
125 .set_parent
= s3c2412_setparent_usysclk
,
129 static struct clk clk_mrefclk
= {
134 static struct clk clk_mdivclk
= {
139 static int s3c2412_setparent_usbsrc(struct clk
*clk
, struct clk
*parent
)
141 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
143 if (parent
== &clk_usysclk
)
144 clksrc
&= ~S3C2412_CLKSRC_USBCLK_HCLK
;
145 else if (parent
== &clk_h
)
146 clksrc
|= S3C2412_CLKSRC_USBCLK_HCLK
;
150 clk
->parent
= parent
;
152 __raw_writel(clksrc
, S3C2412_CLKSRC
);
156 static unsigned long s3c2412_roundrate_usbsrc(struct clk
*clk
,
159 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
162 if (rate
> parent_rate
)
165 div
= parent_rate
/ rate
;
169 return parent_rate
/ div
;
172 static unsigned long s3c2412_getrate_usbsrc(struct clk
*clk
)
174 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
175 unsigned long div
= __raw_readl(S3C2410_CLKDIVN
);
177 return parent_rate
/ ((div
& S3C2412_CLKDIVN_USB48DIV
) ? 2 : 1);
180 static int s3c2412_setrate_usbsrc(struct clk
*clk
, unsigned long rate
)
182 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
183 unsigned long clkdivn
= __raw_readl(S3C2410_CLKDIVN
);
185 rate
= s3c2412_roundrate_usbsrc(clk
, rate
);
187 if ((parent_rate
/ rate
) == 2)
188 clkdivn
|= S3C2412_CLKDIVN_USB48DIV
;
190 clkdivn
&= ~S3C2412_CLKDIVN_USB48DIV
;
192 __raw_writel(clkdivn
, S3C2410_CLKDIVN
);
196 static struct clk clk_usbsrc
= {
198 .ops
= &(struct clk_ops
) {
199 .get_rate
= s3c2412_getrate_usbsrc
,
200 .set_rate
= s3c2412_setrate_usbsrc
,
201 .round_rate
= s3c2412_roundrate_usbsrc
,
202 .set_parent
= s3c2412_setparent_usbsrc
,
206 static int s3c2412_setparent_msysclk(struct clk
*clk
, struct clk
*parent
)
208 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
210 if (parent
== &clk_mdivclk
)
211 clksrc
&= ~S3C2412_CLKSRC_MSYSCLK_MPLL
;
212 else if (parent
== &clk_mpll
)
213 clksrc
|= S3C2412_CLKSRC_MSYSCLK_MPLL
;
217 clk
->parent
= parent
;
219 __raw_writel(clksrc
, S3C2412_CLKSRC
);
223 static struct clk clk_msysclk
= {
225 .ops
= &(struct clk_ops
) {
226 .set_parent
= s3c2412_setparent_msysclk
,
230 static int s3c2412_setparent_armclk(struct clk
*clk
, struct clk
*parent
)
233 unsigned long clkdiv
;
236 /* Note, we current equate fclk andf msysclk for S3C2412 */
238 if (parent
== &clk_msysclk
|| parent
== &clk_f
)
240 else if (parent
== &clk_h
)
241 dvs
= S3C2412_CLKDIVN_DVSEN
;
245 clk
->parent
= parent
;
247 /* update this under irq lockdown, clkdivn is not protected
248 * by the clock system. */
250 local_irq_save(flags
);
252 clkdiv
= __raw_readl(S3C2410_CLKDIVN
);
253 clkdiv
&= ~S3C2412_CLKDIVN_DVSEN
;
255 __raw_writel(clkdiv
, S3C2410_CLKDIVN
);
257 local_irq_restore(flags
);
262 static struct clk clk_armclk
= {
264 .parent
= &clk_msysclk
,
265 .ops
= &(struct clk_ops
) {
266 .set_parent
= s3c2412_setparent_armclk
,
270 /* these next clocks have an divider immediately after them,
271 * so we can register them with their divider and leave out the
272 * intermediate clock stage
274 static unsigned long s3c2412_roundrate_clksrc(struct clk
*clk
,
277 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
280 if (rate
> parent_rate
)
283 /* note, we remove the +/- 1 calculations as they cancel out */
285 div
= (rate
/ parent_rate
);
292 return parent_rate
/ div
;
295 static int s3c2412_setparent_uart(struct clk
*clk
, struct clk
*parent
)
297 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
299 if (parent
== &clk_erefclk
)
300 clksrc
&= ~S3C2412_CLKSRC_UARTCLK_MPLL
;
301 else if (parent
== &clk_mpll
)
302 clksrc
|= S3C2412_CLKSRC_UARTCLK_MPLL
;
306 clk
->parent
= parent
;
308 __raw_writel(clksrc
, S3C2412_CLKSRC
);
312 static unsigned long s3c2412_getrate_uart(struct clk
*clk
)
314 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
315 unsigned long div
= __raw_readl(S3C2410_CLKDIVN
);
317 div
&= S3C2412_CLKDIVN_UARTDIV_MASK
;
318 div
>>= S3C2412_CLKDIVN_UARTDIV_SHIFT
;
320 return parent_rate
/ (div
+ 1);
323 static int s3c2412_setrate_uart(struct clk
*clk
, unsigned long rate
)
325 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
326 unsigned long clkdivn
= __raw_readl(S3C2410_CLKDIVN
);
328 rate
= s3c2412_roundrate_clksrc(clk
, rate
);
330 clkdivn
&= ~S3C2412_CLKDIVN_UARTDIV_MASK
;
331 clkdivn
|= ((parent_rate
/ rate
) - 1) << S3C2412_CLKDIVN_UARTDIV_SHIFT
;
333 __raw_writel(clkdivn
, S3C2410_CLKDIVN
);
337 static struct clk clk_uart
= {
339 .ops
= &(struct clk_ops
) {
340 .get_rate
= s3c2412_getrate_uart
,
341 .set_rate
= s3c2412_setrate_uart
,
342 .set_parent
= s3c2412_setparent_uart
,
343 .round_rate
= s3c2412_roundrate_clksrc
,
347 static int s3c2412_setparent_i2s(struct clk
*clk
, struct clk
*parent
)
349 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
351 if (parent
== &clk_erefclk
)
352 clksrc
&= ~S3C2412_CLKSRC_I2SCLK_MPLL
;
353 else if (parent
== &clk_mpll
)
354 clksrc
|= S3C2412_CLKSRC_I2SCLK_MPLL
;
358 clk
->parent
= parent
;
360 __raw_writel(clksrc
, S3C2412_CLKSRC
);
364 static unsigned long s3c2412_getrate_i2s(struct clk
*clk
)
366 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
367 unsigned long div
= __raw_readl(S3C2410_CLKDIVN
);
369 div
&= S3C2412_CLKDIVN_I2SDIV_MASK
;
370 div
>>= S3C2412_CLKDIVN_I2SDIV_SHIFT
;
372 return parent_rate
/ (div
+ 1);
375 static int s3c2412_setrate_i2s(struct clk
*clk
, unsigned long rate
)
377 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
378 unsigned long clkdivn
= __raw_readl(S3C2410_CLKDIVN
);
380 rate
= s3c2412_roundrate_clksrc(clk
, rate
);
382 clkdivn
&= ~S3C2412_CLKDIVN_I2SDIV_MASK
;
383 clkdivn
|= ((parent_rate
/ rate
) - 1) << S3C2412_CLKDIVN_I2SDIV_SHIFT
;
385 __raw_writel(clkdivn
, S3C2410_CLKDIVN
);
389 static struct clk clk_i2s
= {
391 .ops
= &(struct clk_ops
) {
392 .get_rate
= s3c2412_getrate_i2s
,
393 .set_rate
= s3c2412_setrate_i2s
,
394 .set_parent
= s3c2412_setparent_i2s
,
395 .round_rate
= s3c2412_roundrate_clksrc
,
399 static int s3c2412_setparent_cam(struct clk
*clk
, struct clk
*parent
)
401 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
403 if (parent
== &clk_usysclk
)
404 clksrc
&= ~S3C2412_CLKSRC_CAMCLK_HCLK
;
405 else if (parent
== &clk_h
)
406 clksrc
|= S3C2412_CLKSRC_CAMCLK_HCLK
;
410 clk
->parent
= parent
;
412 __raw_writel(clksrc
, S3C2412_CLKSRC
);
415 static unsigned long s3c2412_getrate_cam(struct clk
*clk
)
417 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
418 unsigned long div
= __raw_readl(S3C2410_CLKDIVN
);
420 div
&= S3C2412_CLKDIVN_CAMDIV_MASK
;
421 div
>>= S3C2412_CLKDIVN_CAMDIV_SHIFT
;
423 return parent_rate
/ (div
+ 1);
426 static int s3c2412_setrate_cam(struct clk
*clk
, unsigned long rate
)
428 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
429 unsigned long clkdivn
= __raw_readl(S3C2410_CLKDIVN
);
431 rate
= s3c2412_roundrate_clksrc(clk
, rate
);
433 clkdivn
&= ~S3C2412_CLKDIVN_CAMDIV_MASK
;
434 clkdivn
|= ((parent_rate
/ rate
) - 1) << S3C2412_CLKDIVN_CAMDIV_SHIFT
;
436 __raw_writel(clkdivn
, S3C2410_CLKDIVN
);
440 static struct clk clk_cam
= {
441 .name
= "camif-upll", /* same as 2440 name */
442 .ops
= &(struct clk_ops
) {
443 .get_rate
= s3c2412_getrate_cam
,
444 .set_rate
= s3c2412_setrate_cam
,
445 .set_parent
= s3c2412_setparent_cam
,
446 .round_rate
= s3c2412_roundrate_clksrc
,
450 /* standard clock definitions */
452 static struct clk init_clocks_disable
[] = {
456 .enable
= s3c2412_clkcon_enable
,
457 .ctrlbit
= S3C2412_CLKCON_NAND
,
461 .enable
= s3c2412_clkcon_enable
,
462 .ctrlbit
= S3C2412_CLKCON_SDI
,
466 .enable
= s3c2412_clkcon_enable
,
467 .ctrlbit
= S3C2412_CLKCON_ADC
,
471 .enable
= s3c2412_clkcon_enable
,
472 .ctrlbit
= S3C2412_CLKCON_IIC
,
476 .enable
= s3c2412_clkcon_enable
,
477 .ctrlbit
= S3C2412_CLKCON_IIS
,
481 .enable
= s3c2412_clkcon_enable
,
482 .ctrlbit
= S3C2412_CLKCON_SPI
,
486 static struct clk init_clocks
[] = {
490 .enable
= s3c2412_clkcon_enable
,
491 .ctrlbit
= S3C2412_CLKCON_DMA0
,
495 .enable
= s3c2412_clkcon_enable
,
496 .ctrlbit
= S3C2412_CLKCON_DMA1
,
500 .enable
= s3c2412_clkcon_enable
,
501 .ctrlbit
= S3C2412_CLKCON_DMA2
,
505 .enable
= s3c2412_clkcon_enable
,
506 .ctrlbit
= S3C2412_CLKCON_DMA3
,
510 .enable
= s3c2412_clkcon_enable
,
511 .ctrlbit
= S3C2412_CLKCON_LCDC
,
515 .enable
= s3c2412_clkcon_enable
,
516 .ctrlbit
= S3C2412_CLKCON_GPIO
,
520 .enable
= s3c2412_clkcon_enable
,
521 .ctrlbit
= S3C2412_CLKCON_USBH
,
523 .name
= "usb-device",
525 .enable
= s3c2412_clkcon_enable
,
526 .ctrlbit
= S3C2412_CLKCON_USBD
,
530 .enable
= s3c2412_clkcon_enable
,
531 .ctrlbit
= S3C2412_CLKCON_PWMT
,
534 .devname
= "s3c2412-uart.0",
536 .enable
= s3c2412_clkcon_enable
,
537 .ctrlbit
= S3C2412_CLKCON_UART0
,
540 .devname
= "s3c2412-uart.1",
542 .enable
= s3c2412_clkcon_enable
,
543 .ctrlbit
= S3C2412_CLKCON_UART1
,
546 .devname
= "s3c2412-uart.2",
548 .enable
= s3c2412_clkcon_enable
,
549 .ctrlbit
= S3C2412_CLKCON_UART2
,
553 .enable
= s3c2412_clkcon_enable
,
554 .ctrlbit
= S3C2412_CLKCON_RTC
,
560 .name
= "usb-bus-gadget",
561 .parent
= &clk_usb_bus
,
562 .enable
= s3c2412_clkcon_enable
,
563 .ctrlbit
= S3C2412_CLKCON_USB_DEV48
,
565 .name
= "usb-bus-host",
566 .parent
= &clk_usb_bus
,
567 .enable
= s3c2412_clkcon_enable
,
568 .ctrlbit
= S3C2412_CLKCON_USB_HOST48
,
572 /* clocks to add where we need to check their parentage */
581 static struct clk_init clks_src
[] __initdata
= {
584 .bit
= S3C2412_CLKSRC_USBCLK_HCLK
,
585 .src_0
= &clk_urefclk
,
589 .bit
= S3C2412_CLKSRC_I2SCLK_MPLL
,
590 .src_0
= &clk_erefclk
,
594 .bit
= S3C2412_CLKSRC_CAMCLK_HCLK
,
595 .src_0
= &clk_usysclk
,
599 .bit
= S3C2412_CLKSRC_MSYSCLK_MPLL
,
600 .src_0
= &clk_mdivclk
,
604 .bit
= S3C2412_CLKSRC_UARTCLK_MPLL
,
605 .src_0
= &clk_erefclk
,
609 .bit
= S3C2412_CLKSRC_USBCLK_HCLK
,
610 .src_0
= &clk_usysclk
,
612 /* here we assume OM[4] select xtal */
615 .bit
= S3C2412_CLKSRC_EREFCLK_EXTCLK
,
620 .bit
= S3C2412_CLKSRC_UREFCLK_EXTCLK
,
626 /* s3c2412_clk_initparents
628 * Initialise the parents for the clocks that we get at start-time
631 static void __init
s3c2412_clk_initparents(void)
633 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
634 struct clk_init
*cip
= clks_src
;
639 for (ptr
= 0; ptr
< ARRAY_SIZE(clks_src
); ptr
++, cip
++) {
640 ret
= s3c24xx_register_clock(cip
->clk
);
642 printk(KERN_ERR
"Failed to register clock %s (%d)\n",
643 cip
->clk
->name
, ret
);
646 src
= (clksrc
& cip
->bit
) ? cip
->src_1
: cip
->src_0
;
648 printk(KERN_INFO
"%s: parent %s\n", cip
->clk
->name
, src
->name
);
649 clk_set_parent(cip
->clk
, src
);
653 /* clocks to add straight away */
655 static struct clk
*clks
[] __initdata
= {
662 int __init
s3c2412_baseclk_add(void)
664 unsigned long clkcon
= __raw_readl(S3C2410_CLKCON
);
670 clk_upll
.enable
= s3c2412_upll_enable
;
671 clk_usb_bus
.parent
= &clk_usbsrc
;
672 clk_usb_bus
.rate
= 0x0;
674 clk_f
.parent
= &clk_msysclk
;
676 s3c2412_clk_initparents();
678 for (ptr
= 0; ptr
< ARRAY_SIZE(clks
); ptr
++) {
681 ret
= s3c24xx_register_clock(clkp
);
683 printk(KERN_ERR
"Failed to register clock %s (%d)\n",
688 /* set the dvs state according to what we got at boot time */
690 dvs
= __raw_readl(S3C2410_CLKDIVN
) & S3C2412_CLKDIVN_DVSEN
;
693 clk_armclk
.parent
= &clk_h
;
695 printk(KERN_INFO
"S3C2412: DVS is %s\n", dvs
? "on" : "off");
697 /* ensure usb bus clock is within correct rate of 48MHz */
699 if (clk_get_rate(&clk_usb_bus
) != (48 * 1000 * 1000)) {
700 printk(KERN_INFO
"Warning: USB bus clock not at 48MHz\n");
702 /* for the moment, let's use the UPLL, and see if we can
705 clk_set_parent(&clk_usysclk
, &clk_upll
);
706 clk_set_parent(&clk_usbsrc
, &clk_usysclk
);
707 clk_set_rate(&clk_usbsrc
, 48*1000*1000);
710 printk("S3C2412: upll %s, %ld.%03ld MHz, usb-bus %ld.%03ld MHz\n",
711 (__raw_readl(S3C2410_UPLLCON
) & S3C2412_PLLCON_OFF
) ? "off":"on",
712 print_mhz(clk_get_rate(&clk_upll
)),
713 print_mhz(clk_get_rate(&clk_usb_bus
)));
715 /* register clocks from clock array */
718 for (ptr
= 0; ptr
< ARRAY_SIZE(init_clocks
); ptr
++, clkp
++) {
719 /* ensure that we note the clock state */
721 clkp
->usage
= clkcon
& clkp
->ctrlbit
? 1 : 0;
723 ret
= s3c24xx_register_clock(clkp
);
725 printk(KERN_ERR
"Failed to register clock %s (%d)\n",
730 /* We must be careful disabling the clocks we are not intending to
731 * be using at boot time, as subsystems such as the LCD which do
732 * their own DMA requests to the bus can cause the system to lockup
733 * if they where in the middle of requesting bus access.
735 * Disabling the LCD clock if the LCD is active is very dangerous,
736 * and therefore the bootloader should be careful to not enable
737 * the LCD clock if it is not needed.
740 /* install (and disable) the clocks we do not need immediately */
742 clkp
= init_clocks_disable
;
743 for (ptr
= 0; ptr
< ARRAY_SIZE(init_clocks_disable
); ptr
++, clkp
++) {
745 ret
= s3c24xx_register_clock(clkp
);
747 printk(KERN_ERR
"Failed to register clock %s (%d)\n",
751 s3c2412_clkcon_enable(clkp
, 0);