1 /* linux/arch/arm/mach-s3c2410/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/arch/regs-serial.h>
41 #include <asm/arch/regs-clock.h>
42 #include <asm/arch/regs-gpio.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);