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 <asm/hardware.h>
40 #include <asm/plat-s3c/regs-serial.h>
41 #include <asm/arch/regs-clock.h>
42 #include <asm/arch/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_upll
)
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 /* these next clocks have an divider immediately after them,
238 * so we can register them with their divider and leave out the
239 * intermediate clock stage
241 static unsigned long s3c2412_roundrate_clksrc(struct clk
*clk
,
244 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
247 if (rate
> parent_rate
)
250 /* note, we remove the +/- 1 calculations as they cancel out */
252 div
= (rate
/ parent_rate
);
259 return parent_rate
/ div
;
262 static int s3c2412_setparent_uart(struct clk
*clk
, struct clk
*parent
)
264 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
266 if (parent
== &clk_erefclk
)
267 clksrc
&= ~S3C2412_CLKSRC_UARTCLK_MPLL
;
268 else if (parent
== &clk_mpll
)
269 clksrc
|= S3C2412_CLKSRC_UARTCLK_MPLL
;
273 clk
->parent
= parent
;
275 __raw_writel(clksrc
, S3C2412_CLKSRC
);
279 static unsigned long s3c2412_getrate_uart(struct clk
*clk
)
281 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
282 unsigned long div
= __raw_readl(S3C2410_CLKDIVN
);
284 div
&= S3C2412_CLKDIVN_UARTDIV_MASK
;
285 div
>>= S3C2412_CLKDIVN_UARTDIV_SHIFT
;
287 return parent_rate
/ (div
+ 1);
290 static int s3c2412_setrate_uart(struct clk
*clk
, unsigned long rate
)
292 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
293 unsigned long clkdivn
= __raw_readl(S3C2410_CLKDIVN
);
295 rate
= s3c2412_roundrate_clksrc(clk
, rate
);
297 clkdivn
&= ~S3C2412_CLKDIVN_UARTDIV_MASK
;
298 clkdivn
|= ((parent_rate
/ rate
) - 1) << S3C2412_CLKDIVN_UARTDIV_SHIFT
;
300 __raw_writel(clkdivn
, S3C2410_CLKDIVN
);
304 static struct clk clk_uart
= {
307 .get_rate
= s3c2412_getrate_uart
,
308 .set_rate
= s3c2412_setrate_uart
,
309 .set_parent
= s3c2412_setparent_uart
,
310 .round_rate
= s3c2412_roundrate_clksrc
,
313 static int s3c2412_setparent_i2s(struct clk
*clk
, struct clk
*parent
)
315 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
317 if (parent
== &clk_erefclk
)
318 clksrc
&= ~S3C2412_CLKSRC_I2SCLK_MPLL
;
319 else if (parent
== &clk_mpll
)
320 clksrc
|= S3C2412_CLKSRC_I2SCLK_MPLL
;
324 clk
->parent
= parent
;
326 __raw_writel(clksrc
, S3C2412_CLKSRC
);
330 static unsigned long s3c2412_getrate_i2s(struct clk
*clk
)
332 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
333 unsigned long div
= __raw_readl(S3C2410_CLKDIVN
);
335 div
&= S3C2412_CLKDIVN_I2SDIV_MASK
;
336 div
>>= S3C2412_CLKDIVN_I2SDIV_SHIFT
;
338 return parent_rate
/ (div
+ 1);
341 static int s3c2412_setrate_i2s(struct clk
*clk
, unsigned long rate
)
343 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
344 unsigned long clkdivn
= __raw_readl(S3C2410_CLKDIVN
);
346 rate
= s3c2412_roundrate_clksrc(clk
, rate
);
348 clkdivn
&= ~S3C2412_CLKDIVN_I2SDIV_MASK
;
349 clkdivn
|= ((parent_rate
/ rate
) - 1) << S3C2412_CLKDIVN_I2SDIV_SHIFT
;
351 __raw_writel(clkdivn
, S3C2410_CLKDIVN
);
355 static struct clk clk_i2s
= {
358 .get_rate
= s3c2412_getrate_i2s
,
359 .set_rate
= s3c2412_setrate_i2s
,
360 .set_parent
= s3c2412_setparent_i2s
,
361 .round_rate
= s3c2412_roundrate_clksrc
,
364 static int s3c2412_setparent_cam(struct clk
*clk
, struct clk
*parent
)
366 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
368 if (parent
== &clk_usysclk
)
369 clksrc
&= ~S3C2412_CLKSRC_CAMCLK_HCLK
;
370 else if (parent
== &clk_h
)
371 clksrc
|= S3C2412_CLKSRC_CAMCLK_HCLK
;
375 clk
->parent
= parent
;
377 __raw_writel(clksrc
, S3C2412_CLKSRC
);
380 static unsigned long s3c2412_getrate_cam(struct clk
*clk
)
382 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
383 unsigned long div
= __raw_readl(S3C2410_CLKDIVN
);
385 div
&= S3C2412_CLKDIVN_CAMDIV_MASK
;
386 div
>>= S3C2412_CLKDIVN_CAMDIV_SHIFT
;
388 return parent_rate
/ (div
+ 1);
391 static int s3c2412_setrate_cam(struct clk
*clk
, unsigned long rate
)
393 unsigned long parent_rate
= clk_get_rate(clk
->parent
);
394 unsigned long clkdivn
= __raw_readl(S3C2410_CLKDIVN
);
396 rate
= s3c2412_roundrate_clksrc(clk
, rate
);
398 clkdivn
&= ~S3C2412_CLKDIVN_CAMDIV_MASK
;
399 clkdivn
|= ((parent_rate
/ rate
) - 1) << S3C2412_CLKDIVN_CAMDIV_SHIFT
;
401 __raw_writel(clkdivn
, S3C2410_CLKDIVN
);
405 static struct clk clk_cam
= {
406 .name
= "camif-upll", /* same as 2440 name */
408 .get_rate
= s3c2412_getrate_cam
,
409 .set_rate
= s3c2412_setrate_cam
,
410 .set_parent
= s3c2412_setparent_cam
,
411 .round_rate
= s3c2412_roundrate_clksrc
,
414 /* standard clock definitions */
416 static struct clk init_clocks_disable
[] = {
421 .enable
= s3c2412_clkcon_enable
,
422 .ctrlbit
= S3C2412_CLKCON_NAND
,
427 .enable
= s3c2412_clkcon_enable
,
428 .ctrlbit
= S3C2412_CLKCON_SDI
,
433 .enable
= s3c2412_clkcon_enable
,
434 .ctrlbit
= S3C2412_CLKCON_ADC
,
439 .enable
= s3c2412_clkcon_enable
,
440 .ctrlbit
= S3C2412_CLKCON_IIC
,
445 .enable
= s3c2412_clkcon_enable
,
446 .ctrlbit
= S3C2412_CLKCON_IIS
,
451 .enable
= s3c2412_clkcon_enable
,
452 .ctrlbit
= S3C2412_CLKCON_SPI
,
456 static struct clk init_clocks
[] = {
461 .enable
= s3c2412_clkcon_enable
,
462 .ctrlbit
= S3C2412_CLKCON_DMA0
,
467 .enable
= s3c2412_clkcon_enable
,
468 .ctrlbit
= S3C2412_CLKCON_DMA1
,
473 .enable
= s3c2412_clkcon_enable
,
474 .ctrlbit
= S3C2412_CLKCON_DMA2
,
479 .enable
= s3c2412_clkcon_enable
,
480 .ctrlbit
= S3C2412_CLKCON_DMA3
,
485 .enable
= s3c2412_clkcon_enable
,
486 .ctrlbit
= S3C2412_CLKCON_LCDC
,
491 .enable
= s3c2412_clkcon_enable
,
492 .ctrlbit
= S3C2412_CLKCON_GPIO
,
497 .enable
= s3c2412_clkcon_enable
,
498 .ctrlbit
= S3C2412_CLKCON_USBH
,
500 .name
= "usb-device",
503 .enable
= s3c2412_clkcon_enable
,
504 .ctrlbit
= S3C2412_CLKCON_USBD
,
509 .enable
= s3c2412_clkcon_enable
,
510 .ctrlbit
= S3C2412_CLKCON_PWMT
,
515 .enable
= s3c2412_clkcon_enable
,
516 .ctrlbit
= S3C2412_CLKCON_UART0
,
521 .enable
= s3c2412_clkcon_enable
,
522 .ctrlbit
= S3C2412_CLKCON_UART1
,
527 .enable
= s3c2412_clkcon_enable
,
528 .ctrlbit
= S3C2412_CLKCON_UART2
,
533 .enable
= s3c2412_clkcon_enable
,
534 .ctrlbit
= S3C2412_CLKCON_RTC
,
541 .name
= "usb-bus-gadget",
543 .parent
= &clk_usb_bus
,
544 .enable
= s3c2412_clkcon_enable
,
545 .ctrlbit
= S3C2412_CLKCON_USB_DEV48
,
547 .name
= "usb-bus-host",
549 .parent
= &clk_usb_bus
,
550 .enable
= s3c2412_clkcon_enable
,
551 .ctrlbit
= S3C2412_CLKCON_USB_HOST48
,
555 /* clocks to add where we need to check their parentage */
564 static struct clk_init clks_src
[] __initdata
= {
567 .bit
= S3C2412_CLKSRC_USBCLK_HCLK
,
568 .src_0
= &clk_urefclk
,
572 .bit
= S3C2412_CLKSRC_I2SCLK_MPLL
,
573 .src_0
= &clk_erefclk
,
577 .bit
= S3C2412_CLKSRC_CAMCLK_HCLK
,
578 .src_0
= &clk_usysclk
,
582 .bit
= S3C2412_CLKSRC_MSYSCLK_MPLL
,
583 .src_0
= &clk_mdivclk
,
587 .bit
= S3C2412_CLKSRC_UARTCLK_MPLL
,
588 .src_0
= &clk_erefclk
,
592 .bit
= S3C2412_CLKSRC_USBCLK_HCLK
,
593 .src_0
= &clk_usysclk
,
598 /* s3c2412_clk_initparents
600 * Initialise the parents for the clocks that we get at start-time
603 static void __init
s3c2412_clk_initparents(void)
605 unsigned long clksrc
= __raw_readl(S3C2412_CLKSRC
);
606 struct clk_init
*cip
= clks_src
;
611 for (ptr
= 0; ptr
< ARRAY_SIZE(clks_src
); ptr
++, cip
++) {
612 ret
= s3c24xx_register_clock(cip
->clk
);
614 printk(KERN_ERR
"Failed to register clock %s (%d)\n",
615 cip
->clk
->name
, ret
);
618 src
= (clksrc
& cip
->bit
) ? cip
->src_1
: cip
->src_0
;
620 printk(KERN_INFO
"%s: parent %s\n", cip
->clk
->name
, src
->name
);
621 clk_set_parent(cip
->clk
, src
);
625 /* clocks to add straight away */
627 static struct clk
*clks
[] __initdata
= {
635 int __init
s3c2412_baseclk_add(void)
637 unsigned long clkcon
= __raw_readl(S3C2410_CLKCON
);
642 clk_upll
.enable
= s3c2412_upll_enable
;
643 clk_usb_bus
.parent
= &clk_usbsrc
;
644 clk_usb_bus
.rate
= 0x0;
646 s3c2412_clk_initparents();
648 for (ptr
= 0; ptr
< ARRAY_SIZE(clks
); ptr
++) {
651 ret
= s3c24xx_register_clock(clkp
);
653 printk(KERN_ERR
"Failed to register clock %s (%d)\n",
658 /* ensure usb bus clock is within correct rate of 48MHz */
660 if (clk_get_rate(&clk_usb_bus
) != (48 * 1000 * 1000)) {
661 printk(KERN_INFO
"Warning: USB bus clock not at 48MHz\n");
663 /* for the moment, let's use the UPLL, and see if we can
666 clk_set_parent(&clk_usysclk
, &clk_upll
);
667 clk_set_parent(&clk_usbsrc
, &clk_usysclk
);
668 clk_set_rate(&clk_usbsrc
, 48*1000*1000);
671 printk("S3C2412: upll %s, %ld.%03ld MHz, usb-bus %ld.%03ld MHz\n",
672 (__raw_readl(S3C2410_UPLLCON
) & S3C2412_PLLCON_OFF
) ? "off":"on",
673 print_mhz(clk_get_rate(&clk_upll
)),
674 print_mhz(clk_get_rate(&clk_usb_bus
)));
676 /* register clocks from clock array */
679 for (ptr
= 0; ptr
< ARRAY_SIZE(init_clocks
); ptr
++, clkp
++) {
680 /* ensure that we note the clock state */
682 clkp
->usage
= clkcon
& clkp
->ctrlbit
? 1 : 0;
684 ret
= s3c24xx_register_clock(clkp
);
686 printk(KERN_ERR
"Failed to register clock %s (%d)\n",
691 /* We must be careful disabling the clocks we are not intending to
692 * be using at boot time, as subsytems such as the LCD which do
693 * their own DMA requests to the bus can cause the system to lockup
694 * if they where in the middle of requesting bus access.
696 * Disabling the LCD clock if the LCD is active is very dangerous,
697 * and therefore the bootloader should be careful to not enable
698 * the LCD clock if it is not needed.
701 /* install (and disable) the clocks we do not need immediately */
703 clkp
= init_clocks_disable
;
704 for (ptr
= 0; ptr
< ARRAY_SIZE(init_clocks_disable
); ptr
++, clkp
++) {
706 ret
= s3c24xx_register_clock(clkp
);
708 printk(KERN_ERR
"Failed to register clock %s (%d)\n",
712 s3c2412_clkcon_enable(clkp
, 0);