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>
35 #include <asm/mach/map.h>
37 #include <mach/hardware.h>
40 #include <asm/plat-s3c/regs-serial.h>
41 #include <mach/regs-clock.h>
42 #include <mach/regs-gpio.h>
44 #include <asm/plat-s3c24xx/s3c2412.h>
45 #include <asm/plat-s3c24xx/clock.h>
46 #include <asm/plat-s3c24xx/cpu.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 /* CPU EXTCLK input */
97 static struct clk clk_ext
= {
102 static struct clk clk_erefclk
= {
107 static struct clk clk_urefclk
= {
112 static int s3c2412_setparent_usysclk(struct clk
*clk
, struct clk
*parent
)
114 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
116 if (parent
== &clk_urefclk
)
117 clksrc
&= ~S3C2412_CLKSRC_USYSCLK_UPLL
;
118 else if (parent
== &clk_upll
)
119 clksrc
|= S3C2412_CLKSRC_USYSCLK_UPLL
;
123 clk
->parent
= parent
;
125 __raw_writel(clksrc
, S3C2412_CLKSRC
);
129 static struct clk clk_usysclk
= {
133 .set_parent
= s3c2412_setparent_usysclk
,
136 static struct clk clk_mrefclk
= {
142 static struct clk clk_mdivclk
= {
148 static int s3c2412_setparent_usbsrc(struct clk
*clk
, struct clk
*parent
)
150 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
152 if (parent
== &clk_usysclk
)
153 clksrc
&= ~S3C2412_CLKSRC_USBCLK_HCLK
;
154 else if (parent
== &clk_h
)
155 clksrc
|= S3C2412_CLKSRC_USBCLK_HCLK
;
159 clk
->parent
= parent
;
161 __raw_writel(clksrc
, S3C2412_CLKSRC
);
165 static unsigned long s3c2412_roundrate_usbsrc(struct clk
*clk
,
168 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
171 if (rate
> parent_rate
)
174 div
= parent_rate
/ rate
;
178 return parent_rate
/ div
;
181 static unsigned long s3c2412_getrate_usbsrc(struct clk
*clk
)
183 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
184 unsigned long div
= __raw_readl(S3C2410_CLKDIVN
);
186 return parent_rate
/ ((div
& S3C2412_CLKDIVN_USB48DIV
) ? 2 : 1);
189 static int s3c2412_setrate_usbsrc(struct clk
*clk
, unsigned long rate
)
191 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
192 unsigned long clkdivn
= __raw_readl(S3C2410_CLKDIVN
);
194 rate
= s3c2412_roundrate_usbsrc(clk
, rate
);
196 if ((parent_rate
/ rate
) == 2)
197 clkdivn
|= S3C2412_CLKDIVN_USB48DIV
;
199 clkdivn
&= ~S3C2412_CLKDIVN_USB48DIV
;
201 __raw_writel(clkdivn
, S3C2410_CLKDIVN
);
205 static struct clk clk_usbsrc
= {
208 .get_rate
= s3c2412_getrate_usbsrc
,
209 .set_rate
= s3c2412_setrate_usbsrc
,
210 .round_rate
= s3c2412_roundrate_usbsrc
,
211 .set_parent
= s3c2412_setparent_usbsrc
,
214 static int s3c2412_setparent_msysclk(struct clk
*clk
, struct clk
*parent
)
216 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
218 if (parent
== &clk_mdivclk
)
219 clksrc
&= ~S3C2412_CLKSRC_MSYSCLK_MPLL
;
220 else if (parent
== &clk_mpll
)
221 clksrc
|= S3C2412_CLKSRC_MSYSCLK_MPLL
;
225 clk
->parent
= parent
;
227 __raw_writel(clksrc
, S3C2412_CLKSRC
);
231 static struct clk clk_msysclk
= {
234 .set_parent
= s3c2412_setparent_msysclk
,
237 static int s3c2412_setparent_armclk(struct clk
*clk
, struct clk
*parent
)
240 unsigned long clkdiv
;
243 /* Note, we current equate fclk andf msysclk for S3C2412 */
245 if (parent
== &clk_msysclk
|| parent
== &clk_f
)
247 else if (parent
== &clk_h
)
248 dvs
= S3C2412_CLKDIVN_DVSEN
;
252 clk
->parent
= parent
;
254 /* update this under irq lockdown, clkdivn is not protected
255 * by the clock system. */
257 local_irq_save(flags
);
259 clkdiv
= __raw_readl(S3C2410_CLKDIVN
);
260 clkdiv
&= ~S3C2412_CLKDIVN_DVSEN
;
262 __raw_writel(clkdiv
, S3C2410_CLKDIVN
);
264 local_irq_restore(flags
);
269 static struct clk clk_armclk
= {
272 .parent
= &clk_msysclk
,
273 .set_parent
= s3c2412_setparent_armclk
,
276 /* these next clocks have an divider immediately after them,
277 * so we can register them with their divider and leave out the
278 * intermediate clock stage
280 static unsigned long s3c2412_roundrate_clksrc(struct clk
*clk
,
283 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
286 if (rate
> parent_rate
)
289 /* note, we remove the +/- 1 calculations as they cancel out */
291 div
= (rate
/ parent_rate
);
298 return parent_rate
/ div
;
301 static int s3c2412_setparent_uart(struct clk
*clk
, struct clk
*parent
)
303 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
305 if (parent
== &clk_erefclk
)
306 clksrc
&= ~S3C2412_CLKSRC_UARTCLK_MPLL
;
307 else if (parent
== &clk_mpll
)
308 clksrc
|= S3C2412_CLKSRC_UARTCLK_MPLL
;
312 clk
->parent
= parent
;
314 __raw_writel(clksrc
, S3C2412_CLKSRC
);
318 static unsigned long s3c2412_getrate_uart(struct clk
*clk
)
320 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
321 unsigned long div
= __raw_readl(S3C2410_CLKDIVN
);
323 div
&= S3C2412_CLKDIVN_UARTDIV_MASK
;
324 div
>>= S3C2412_CLKDIVN_UARTDIV_SHIFT
;
326 return parent_rate
/ (div
+ 1);
329 static int s3c2412_setrate_uart(struct clk
*clk
, unsigned long rate
)
331 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
332 unsigned long clkdivn
= __raw_readl(S3C2410_CLKDIVN
);
334 rate
= s3c2412_roundrate_clksrc(clk
, rate
);
336 clkdivn
&= ~S3C2412_CLKDIVN_UARTDIV_MASK
;
337 clkdivn
|= ((parent_rate
/ rate
) - 1) << S3C2412_CLKDIVN_UARTDIV_SHIFT
;
339 __raw_writel(clkdivn
, S3C2410_CLKDIVN
);
343 static struct clk clk_uart
= {
346 .get_rate
= s3c2412_getrate_uart
,
347 .set_rate
= s3c2412_setrate_uart
,
348 .set_parent
= s3c2412_setparent_uart
,
349 .round_rate
= s3c2412_roundrate_clksrc
,
352 static int s3c2412_setparent_i2s(struct clk
*clk
, struct clk
*parent
)
354 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
356 if (parent
== &clk_erefclk
)
357 clksrc
&= ~S3C2412_CLKSRC_I2SCLK_MPLL
;
358 else if (parent
== &clk_mpll
)
359 clksrc
|= S3C2412_CLKSRC_I2SCLK_MPLL
;
363 clk
->parent
= parent
;
365 __raw_writel(clksrc
, S3C2412_CLKSRC
);
369 static unsigned long s3c2412_getrate_i2s(struct clk
*clk
)
371 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
372 unsigned long div
= __raw_readl(S3C2410_CLKDIVN
);
374 div
&= S3C2412_CLKDIVN_I2SDIV_MASK
;
375 div
>>= S3C2412_CLKDIVN_I2SDIV_SHIFT
;
377 return parent_rate
/ (div
+ 1);
380 static int s3c2412_setrate_i2s(struct clk
*clk
, unsigned long rate
)
382 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
383 unsigned long clkdivn
= __raw_readl(S3C2410_CLKDIVN
);
385 rate
= s3c2412_roundrate_clksrc(clk
, rate
);
387 clkdivn
&= ~S3C2412_CLKDIVN_I2SDIV_MASK
;
388 clkdivn
|= ((parent_rate
/ rate
) - 1) << S3C2412_CLKDIVN_I2SDIV_SHIFT
;
390 __raw_writel(clkdivn
, S3C2410_CLKDIVN
);
394 static struct clk clk_i2s
= {
397 .get_rate
= s3c2412_getrate_i2s
,
398 .set_rate
= s3c2412_setrate_i2s
,
399 .set_parent
= s3c2412_setparent_i2s
,
400 .round_rate
= s3c2412_roundrate_clksrc
,
403 static int s3c2412_setparent_cam(struct clk
*clk
, struct clk
*parent
)
405 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
407 if (parent
== &clk_usysclk
)
408 clksrc
&= ~S3C2412_CLKSRC_CAMCLK_HCLK
;
409 else if (parent
== &clk_h
)
410 clksrc
|= S3C2412_CLKSRC_CAMCLK_HCLK
;
414 clk
->parent
= parent
;
416 __raw_writel(clksrc
, S3C2412_CLKSRC
);
419 static unsigned long s3c2412_getrate_cam(struct clk
*clk
)
421 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
422 unsigned long div
= __raw_readl(S3C2410_CLKDIVN
);
424 div
&= S3C2412_CLKDIVN_CAMDIV_MASK
;
425 div
>>= S3C2412_CLKDIVN_CAMDIV_SHIFT
;
427 return parent_rate
/ (div
+ 1);
430 static int s3c2412_setrate_cam(struct clk
*clk
, unsigned long rate
)
432 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
433 unsigned long clkdivn
= __raw_readl(S3C2410_CLKDIVN
);
435 rate
= s3c2412_roundrate_clksrc(clk
, rate
);
437 clkdivn
&= ~S3C2412_CLKDIVN_CAMDIV_MASK
;
438 clkdivn
|= ((parent_rate
/ rate
) - 1) << S3C2412_CLKDIVN_CAMDIV_SHIFT
;
440 __raw_writel(clkdivn
, S3C2410_CLKDIVN
);
444 static struct clk clk_cam
= {
445 .name
= "camif-upll", /* same as 2440 name */
447 .get_rate
= s3c2412_getrate_cam
,
448 .set_rate
= s3c2412_setrate_cam
,
449 .set_parent
= s3c2412_setparent_cam
,
450 .round_rate
= s3c2412_roundrate_clksrc
,
453 /* standard clock definitions */
455 static struct clk init_clocks_disable
[] = {
460 .enable
= s3c2412_clkcon_enable
,
461 .ctrlbit
= S3C2412_CLKCON_NAND
,
466 .enable
= s3c2412_clkcon_enable
,
467 .ctrlbit
= S3C2412_CLKCON_SDI
,
472 .enable
= s3c2412_clkcon_enable
,
473 .ctrlbit
= S3C2412_CLKCON_ADC
,
478 .enable
= s3c2412_clkcon_enable
,
479 .ctrlbit
= S3C2412_CLKCON_IIC
,
484 .enable
= s3c2412_clkcon_enable
,
485 .ctrlbit
= S3C2412_CLKCON_IIS
,
490 .enable
= s3c2412_clkcon_enable
,
491 .ctrlbit
= S3C2412_CLKCON_SPI
,
495 static struct clk init_clocks
[] = {
500 .enable
= s3c2412_clkcon_enable
,
501 .ctrlbit
= S3C2412_CLKCON_DMA0
,
506 .enable
= s3c2412_clkcon_enable
,
507 .ctrlbit
= S3C2412_CLKCON_DMA1
,
512 .enable
= s3c2412_clkcon_enable
,
513 .ctrlbit
= S3C2412_CLKCON_DMA2
,
518 .enable
= s3c2412_clkcon_enable
,
519 .ctrlbit
= S3C2412_CLKCON_DMA3
,
524 .enable
= s3c2412_clkcon_enable
,
525 .ctrlbit
= S3C2412_CLKCON_LCDC
,
530 .enable
= s3c2412_clkcon_enable
,
531 .ctrlbit
= S3C2412_CLKCON_GPIO
,
536 .enable
= s3c2412_clkcon_enable
,
537 .ctrlbit
= S3C2412_CLKCON_USBH
,
539 .name
= "usb-device",
542 .enable
= s3c2412_clkcon_enable
,
543 .ctrlbit
= S3C2412_CLKCON_USBD
,
548 .enable
= s3c2412_clkcon_enable
,
549 .ctrlbit
= S3C2412_CLKCON_PWMT
,
554 .enable
= s3c2412_clkcon_enable
,
555 .ctrlbit
= S3C2412_CLKCON_UART0
,
560 .enable
= s3c2412_clkcon_enable
,
561 .ctrlbit
= S3C2412_CLKCON_UART1
,
566 .enable
= s3c2412_clkcon_enable
,
567 .ctrlbit
= S3C2412_CLKCON_UART2
,
572 .enable
= s3c2412_clkcon_enable
,
573 .ctrlbit
= S3C2412_CLKCON_RTC
,
580 .name
= "usb-bus-gadget",
582 .parent
= &clk_usb_bus
,
583 .enable
= s3c2412_clkcon_enable
,
584 .ctrlbit
= S3C2412_CLKCON_USB_DEV48
,
586 .name
= "usb-bus-host",
588 .parent
= &clk_usb_bus
,
589 .enable
= s3c2412_clkcon_enable
,
590 .ctrlbit
= S3C2412_CLKCON_USB_HOST48
,
594 /* clocks to add where we need to check their parentage */
603 static struct clk_init clks_src
[] __initdata
= {
606 .bit
= S3C2412_CLKSRC_USBCLK_HCLK
,
607 .src_0
= &clk_urefclk
,
611 .bit
= S3C2412_CLKSRC_I2SCLK_MPLL
,
612 .src_0
= &clk_erefclk
,
616 .bit
= S3C2412_CLKSRC_CAMCLK_HCLK
,
617 .src_0
= &clk_usysclk
,
621 .bit
= S3C2412_CLKSRC_MSYSCLK_MPLL
,
622 .src_0
= &clk_mdivclk
,
626 .bit
= S3C2412_CLKSRC_UARTCLK_MPLL
,
627 .src_0
= &clk_erefclk
,
631 .bit
= S3C2412_CLKSRC_USBCLK_HCLK
,
632 .src_0
= &clk_usysclk
,
634 /* here we assume OM[4] select xtal */
637 .bit
= S3C2412_CLKSRC_EREFCLK_EXTCLK
,
642 .bit
= S3C2412_CLKSRC_UREFCLK_EXTCLK
,
648 /* s3c2412_clk_initparents
650 * Initialise the parents for the clocks that we get at start-time
653 static void __init
s3c2412_clk_initparents(void)
655 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
656 struct clk_init
*cip
= clks_src
;
661 for (ptr
= 0; ptr
< ARRAY_SIZE(clks_src
); ptr
++, cip
++) {
662 ret
= s3c24xx_register_clock(cip
->clk
);
664 printk(KERN_ERR
"Failed to register clock %s (%d)\n",
665 cip
->clk
->name
, ret
);
668 src
= (clksrc
& cip
->bit
) ? cip
->src_1
: cip
->src_0
;
670 printk(KERN_INFO
"%s: parent %s\n", cip
->clk
->name
, src
->name
);
671 clk_set_parent(cip
->clk
, src
);
675 /* clocks to add straight away */
677 static struct clk
*clks
[] __initdata
= {
684 int __init
s3c2412_baseclk_add(void)
686 unsigned long clkcon
= __raw_readl(S3C2410_CLKCON
);
692 clk_upll
.enable
= s3c2412_upll_enable
;
693 clk_usb_bus
.parent
= &clk_usbsrc
;
694 clk_usb_bus
.rate
= 0x0;
696 clk_f
.parent
= &clk_msysclk
;
698 s3c2412_clk_initparents();
700 for (ptr
= 0; ptr
< ARRAY_SIZE(clks
); ptr
++) {
703 ret
= s3c24xx_register_clock(clkp
);
705 printk(KERN_ERR
"Failed to register clock %s (%d)\n",
710 /* set the dvs state according to what we got at boot time */
712 dvs
= __raw_readl(S3C2410_CLKDIVN
) & S3C2412_CLKDIVN_DVSEN
;
715 clk_armclk
.parent
= &clk_h
;
717 printk(KERN_INFO
"S3C2412: DVS is %s\n", dvs
? "on" : "off");
719 /* ensure usb bus clock is within correct rate of 48MHz */
721 if (clk_get_rate(&clk_usb_bus
) != (48 * 1000 * 1000)) {
722 printk(KERN_INFO
"Warning: USB bus clock not at 48MHz\n");
724 /* for the moment, let's use the UPLL, and see if we can
727 clk_set_parent(&clk_usysclk
, &clk_upll
);
728 clk_set_parent(&clk_usbsrc
, &clk_usysclk
);
729 clk_set_rate(&clk_usbsrc
, 48*1000*1000);
732 printk("S3C2412: upll %s, %ld.%03ld MHz, usb-bus %ld.%03ld MHz\n",
733 (__raw_readl(S3C2410_UPLLCON
) & S3C2412_PLLCON_OFF
) ? "off":"on",
734 print_mhz(clk_get_rate(&clk_upll
)),
735 print_mhz(clk_get_rate(&clk_usb_bus
)));
737 /* register clocks from clock array */
740 for (ptr
= 0; ptr
< ARRAY_SIZE(init_clocks
); ptr
++, clkp
++) {
741 /* ensure that we note the clock state */
743 clkp
->usage
= clkcon
& clkp
->ctrlbit
? 1 : 0;
745 ret
= s3c24xx_register_clock(clkp
);
747 printk(KERN_ERR
"Failed to register clock %s (%d)\n",
752 /* We must be careful disabling the clocks we are not intending to
753 * be using at boot time, as subsystems such as the LCD which do
754 * their own DMA requests to the bus can cause the system to lockup
755 * if they where in the middle of requesting bus access.
757 * Disabling the LCD clock if the LCD is active is very dangerous,
758 * and therefore the bootloader should be careful to not enable
759 * the LCD clock if it is not needed.
762 /* install (and disable) the clocks we do not need immediately */
764 clkp
= init_clocks_disable
;
765 for (ptr
= 0; ptr
< ARRAY_SIZE(init_clocks_disable
); ptr
++, clkp
++) {
767 ret
= s3c24xx_register_clock(clkp
);
769 printk(KERN_ERR
"Failed to register clock %s (%d)\n",
773 s3c2412_clkcon_enable(clkp
, 0);