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Diffstat (limited to 'arch/arm/mach-s3c24xx/clock-s3c2440.c')
-rw-r--r--arch/arm/mach-s3c24xx/clock-s3c2440.c194
1 files changed, 194 insertions, 0 deletions
diff --git a/arch/arm/mach-s3c24xx/clock-s3c2440.c b/arch/arm/mach-s3c24xx/clock-s3c2440.c
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index 0000000..414364e
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+++ b/arch/arm/mach-s3c24xx/clock-s3c2440.c
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+/* linux/arch/arm/mach-s3c2440/clock.c
+ *
+ * Copyright (c) 2004-2005 Simtec Electronics
+ * http://armlinux.simtec.co.uk/
+ * Ben Dooks <ben@simtec.co.uk>
+ *
+ * S3C2440 Clock support
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+*/
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/mutex.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/serial_core.h>
+
+#include <mach/hardware.h>
+#include <linux/atomic.h>
+#include <asm/irq.h>
+
+#include <mach/regs-clock.h>
+
+#include <plat/clock.h>
+#include <plat/cpu.h>
+#include <plat/regs-serial.h>
+
+/* S3C2440 extended clock support */
+
+static unsigned long s3c2440_camif_upll_round(struct clk *clk,
+ unsigned long rate)
+{
+ unsigned long parent_rate = clk_get_rate(clk->parent);
+ int div;
+
+ if (rate > parent_rate)
+ return parent_rate;
+
+ /* note, we remove the +/- 1 calculations for the divisor */
+
+ div = (parent_rate / rate) / 2;
+
+ if (div < 1)
+ div = 1;
+ else if (div > 16)
+ div = 16;
+
+ return parent_rate / (div * 2);
+}
+
+static int s3c2440_camif_upll_setrate(struct clk *clk, unsigned long rate)
+{
+ unsigned long parent_rate = clk_get_rate(clk->parent);
+ unsigned long camdivn = __raw_readl(S3C2440_CAMDIVN);
+
+ rate = s3c2440_camif_upll_round(clk, rate);
+
+ camdivn &= ~(S3C2440_CAMDIVN_CAMCLK_SEL | S3C2440_CAMDIVN_CAMCLK_MASK);
+
+ if (rate != parent_rate) {
+ camdivn |= S3C2440_CAMDIVN_CAMCLK_SEL;
+ camdivn |= (((parent_rate / rate) / 2) - 1);
+ }
+
+ __raw_writel(camdivn, S3C2440_CAMDIVN);
+
+ return 0;
+}
+
+/* Extra S3C2440 clocks */
+
+static struct clk s3c2440_clk_cam = {
+ .name = "camif",
+ .enable = s3c2410_clkcon_enable,
+ .ctrlbit = S3C2440_CLKCON_CAMERA,
+};
+
+static struct clk s3c2440_clk_cam_upll = {
+ .name = "camif-upll",
+ .ops = &(struct clk_ops) {
+ .set_rate = s3c2440_camif_upll_setrate,
+ .round_rate = s3c2440_camif_upll_round,
+ },
+};
+
+static struct clk s3c2440_clk_ac97 = {
+ .name = "ac97",
+ .enable = s3c2410_clkcon_enable,
+ .ctrlbit = S3C2440_CLKCON_CAMERA,
+};
+
+static unsigned long s3c2440_fclk_n_getrate(struct clk *clk)
+{
+ unsigned long ucon0, ucon1, ucon2, divisor;
+
+ /* the fun of calculating the uart divisors on the s3c2440 */
+ ucon0 = __raw_readl(S3C24XX_VA_UART0 + S3C2410_UCON);
+ ucon1 = __raw_readl(S3C24XX_VA_UART1 + S3C2410_UCON);
+ ucon2 = __raw_readl(S3C24XX_VA_UART2 + S3C2410_UCON);
+
+ ucon0 &= S3C2440_UCON0_DIVMASK;
+ ucon1 &= S3C2440_UCON1_DIVMASK;
+ ucon2 &= S3C2440_UCON2_DIVMASK;
+
+ if (ucon0 != 0)
+ divisor = (ucon0 >> S3C2440_UCON_DIVSHIFT) + 6;
+ else if (ucon1 != 0)
+ divisor = (ucon1 >> S3C2440_UCON_DIVSHIFT) + 21;
+ else if (ucon2 != 0)
+ divisor = (ucon2 >> S3C2440_UCON_DIVSHIFT) + 36;
+ else
+ /* manual calims 44, seems to be 9 */
+ divisor = 9;
+
+ return clk_get_rate(clk->parent) / divisor;
+}
+
+static struct clk s3c2440_clk_fclk_n = {
+ .name = "fclk_n",
+ .parent = &clk_f,
+ .ops = &(struct clk_ops) {
+ .get_rate = s3c2440_fclk_n_getrate,
+ },
+};
+
+static struct clk_lookup s3c2440_clk_lookup[] = {
+ CLKDEV_INIT(NULL, "clk_uart_baud1", &s3c24xx_uclk),
+ CLKDEV_INIT(NULL, "clk_uart_baud2", &clk_p),
+ CLKDEV_INIT(NULL, "clk_uart_baud3", &s3c2440_clk_fclk_n),
+};
+
+static int s3c2440_clk_add(struct device *dev, struct subsys_interface *sif)
+{
+ struct clk *clock_upll;
+ struct clk *clock_h;
+ struct clk *clock_p;
+
+ clock_p = clk_get(NULL, "pclk");
+ clock_h = clk_get(NULL, "hclk");
+ clock_upll = clk_get(NULL, "upll");
+
+ if (IS_ERR(clock_p) || IS_ERR(clock_h) || IS_ERR(clock_upll)) {
+ printk(KERN_ERR "S3C2440: Failed to get parent clocks\n");
+ return -EINVAL;
+ }
+
+ s3c2440_clk_cam.parent = clock_h;
+ s3c2440_clk_ac97.parent = clock_p;
+ s3c2440_clk_cam_upll.parent = clock_upll;
+ s3c24xx_register_clock(&s3c2440_clk_fclk_n);
+
+ s3c24xx_register_clock(&s3c2440_clk_ac97);
+ s3c24xx_register_clock(&s3c2440_clk_cam);
+ s3c24xx_register_clock(&s3c2440_clk_cam_upll);
+ clkdev_add_table(s3c2440_clk_lookup, ARRAY_SIZE(s3c2440_clk_lookup));
+
+ clk_disable(&s3c2440_clk_ac97);
+ clk_disable(&s3c2440_clk_cam);
+
+ return 0;
+}
+
+static struct subsys_interface s3c2440_clk_interface = {
+ .name = "s3c2440_clk",
+ .subsys = &s3c2440_subsys,
+ .add_dev = s3c2440_clk_add,
+};
+
+static __init int s3c24xx_clk_init(void)
+{
+ return subsys_interface_register(&s3c2440_clk_interface);
+}
+
+arch_initcall(s3c24xx_clk_init);