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Diffstat (limited to 'arch/arm/plat-s3c24xx/s3c244x-clock.c')
-rw-r--r--arch/arm/plat-s3c24xx/s3c244x-clock.c137
1 files changed, 137 insertions, 0 deletions
diff --git a/arch/arm/plat-s3c24xx/s3c244x-clock.c b/arch/arm/plat-s3c24xx/s3c244x-clock.c
new file mode 100644
index 000000000000..faf3e0f9f4e2
--- /dev/null
+++ b/arch/arm/plat-s3c24xx/s3c244x-clock.c
@@ -0,0 +1,137 @@
+/* linux/arch/arm/plat-s3c24xx/s3c24xx-clock.c
+ *
+ * Copyright (c) 2004-2005,2008 Simtec Electronics
+ * http://armlinux.simtec.co.uk/
+ * Ben Dooks <ben@simtec.co.uk>
+ *
+ * S3C2440/S3C2442 Common 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/sysdev.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/mutex.h>
+#include <linux/clk.h>
+
+#include <asm/hardware.h>
+#include <asm/atomic.h>
+#include <asm/irq.h>
+#include <asm/io.h>
+
+#include <asm/arch/regs-clock.h>
+
+#include <asm/plat-s3c24xx/clock.h>
+#include <asm/plat-s3c24xx/cpu.h>
+
+static int s3c2440_setparent_armclk(struct clk *clk, struct clk *parent)
+{
+ unsigned long camdivn;
+ unsigned long dvs;
+
+ if (parent == &clk_f)
+ dvs = 0;
+ else if (parent == &clk_h)
+ dvs = S3C2440_CAMDIVN_DVSEN;
+ else
+ return -EINVAL;
+
+ clk->parent = parent;
+
+ camdivn = __raw_readl(S3C2440_CAMDIVN);
+ camdivn &= ~S3C2440_CAMDIVN_DVSEN;
+ camdivn |= dvs;
+ __raw_writel(camdivn, S3C2440_CAMDIVN);
+
+ return 0;
+}
+
+static struct clk clk_arm = {
+ .name = "armclk",
+ .id = -1,
+ .set_parent = s3c2440_setparent_armclk,
+};
+
+static int s3c244x_clk_add(struct sys_device *sysdev)
+{
+ unsigned long camdivn = __raw_readl(S3C2440_CAMDIVN);
+ unsigned long clkdivn;
+ struct clk *clock_upll;
+ int ret;
+
+ printk("S3C244X: Clock Support, DVS %s\n",
+ (camdivn & S3C2440_CAMDIVN_DVSEN) ? "on" : "off");
+
+ clk_arm.parent = (camdivn & S3C2440_CAMDIVN_DVSEN) ? &clk_h : &clk_f;
+
+ ret = s3c24xx_register_clock(&clk_arm);
+ if (ret < 0) {
+ printk(KERN_ERR "S3C24XX: Failed to add armclk (%d)\n", ret);
+ return ret;
+ }
+
+ clock_upll = clk_get(NULL, "upll");
+ if (IS_ERR(clock_upll)) {
+ printk(KERN_ERR "S3C244X: Failed to get upll clock\n");
+ return -ENOENT;
+ }
+
+ /* check rate of UPLL, and if it is near 96MHz, then change
+ * to using half the UPLL rate for the system */
+
+ if (clk_get_rate(clock_upll) > (94 * MHZ)) {
+ clk_usb_bus.rate = clk_get_rate(clock_upll) / 2;
+
+ mutex_lock(&clocks_mutex);
+
+ clkdivn = __raw_readl(S3C2410_CLKDIVN);
+ clkdivn |= S3C2440_CLKDIVN_UCLK;
+ __raw_writel(clkdivn, S3C2410_CLKDIVN);
+
+ mutex_unlock(&clocks_mutex);
+ }
+
+ return 0;
+}
+
+static struct sysdev_driver s3c2440_clk_driver = {
+ .add = s3c244x_clk_add,
+};
+
+static int s3c2440_clk_init(void)
+{
+ return sysdev_driver_register(&s3c2440_sysclass, &s3c2440_clk_driver);
+}
+
+arch_initcall(s3c2440_clk_init);
+
+static struct sysdev_driver s3c2442_clk_driver = {
+ .add = s3c244x_clk_add,
+};
+
+static int s3c2442_clk_init(void)
+{
+ return sysdev_driver_register(&s3c2442_sysclass, &s3c2442_clk_driver);
+}
+
+arch_initcall(s3c2442_clk_init);