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-rw-r--r--arch/arm/plat-s3c/clock.c368
1 files changed, 368 insertions, 0 deletions
diff --git a/arch/arm/plat-s3c/clock.c b/arch/arm/plat-s3c/clock.c
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index 00000000000..b6be76e2fe5
--- /dev/null
+++ b/arch/arm/plat-s3c/clock.c
@@ -0,0 +1,368 @@
+/* linux/arch/arm/plat-s3c24xx/clock.c
+ *
+ * Copyright (c) 2004-2005 Simtec Electronics
+ * Ben Dooks <ben@simtec.co.uk>
+ *
+ * S3C24XX Core clock control support
+ *
+ * Based on, and code from linux/arch/arm/mach-versatile/clock.c
+ **
+ ** Copyright (C) 2004 ARM Limited.
+ ** Written by Deep Blue Solutions Limited.
+ *
+ *
+ * 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/platform_device.h>
+#include <linux/sysdev.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/clk.h>
+#include <linux/spinlock.h>
+#include <linux/io.h>
+
+#include <mach/hardware.h>
+#include <asm/irq.h>
+
+#include <plat/cpu-freq.h>
+
+#include <plat/clock.h>
+#include <plat/cpu.h>
+
+/* clock information */
+
+static LIST_HEAD(clocks);
+
+/* We originally used an mutex here, but some contexts (see resume)
+ * are calling functions such as clk_set_parent() with IRQs disabled
+ * causing an BUG to be triggered.
+ */
+DEFINE_SPINLOCK(clocks_lock);
+
+/* enable and disable calls for use with the clk struct */
+
+static int clk_null_enable(struct clk *clk, int enable)
+{
+ return 0;
+}
+
+/* Clock API calls */
+
+struct clk *clk_get(struct device *dev, const char *id)
+{
+ struct clk *p;
+ struct clk *clk = ERR_PTR(-ENOENT);
+ int idno;
+
+ if (dev == NULL || dev->bus != &platform_bus_type)
+ idno = -1;
+ else
+ idno = to_platform_device(dev)->id;
+
+ spin_lock(&clocks_lock);
+
+ list_for_each_entry(p, &clocks, list) {
+ if (p->id == idno &&
+ strcmp(id, p->name) == 0 &&
+ try_module_get(p->owner)) {
+ clk = p;
+ break;
+ }
+ }
+
+ /* check for the case where a device was supplied, but the
+ * clock that was being searched for is not device specific */
+
+ if (IS_ERR(clk)) {
+ list_for_each_entry(p, &clocks, list) {
+ if (p->id == -1 && strcmp(id, p->name) == 0 &&
+ try_module_get(p->owner)) {
+ clk = p;
+ break;
+ }
+ }
+ }
+
+ spin_unlock(&clocks_lock);
+ return clk;
+}
+
+void clk_put(struct clk *clk)
+{
+ module_put(clk->owner);
+}
+
+int clk_enable(struct clk *clk)
+{
+ if (IS_ERR(clk) || clk == NULL)
+ return -EINVAL;
+
+ clk_enable(clk->parent);
+
+ spin_lock(&clocks_lock);
+
+ if ((clk->usage++) == 0)
+ (clk->enable)(clk, 1);
+
+ spin_unlock(&clocks_lock);
+ return 0;
+}
+
+void clk_disable(struct clk *clk)
+{
+ if (IS_ERR(clk) || clk == NULL)
+ return;
+
+ spin_lock(&clocks_lock);
+
+ if ((--clk->usage) == 0)
+ (clk->enable)(clk, 0);
+
+ spin_unlock(&clocks_lock);
+ clk_disable(clk->parent);
+}
+
+
+unsigned long clk_get_rate(struct clk *clk)
+{
+ if (IS_ERR(clk))
+ return 0;
+
+ if (clk->rate != 0)
+ return clk->rate;
+
+ if (clk->get_rate != NULL)
+ return (clk->get_rate)(clk);
+
+ if (clk->parent != NULL)
+ return clk_get_rate(clk->parent);
+
+ return clk->rate;
+}
+
+long clk_round_rate(struct clk *clk, unsigned long rate)
+{
+ if (!IS_ERR(clk) && clk->round_rate)
+ return (clk->round_rate)(clk, rate);
+
+ return rate;
+}
+
+int clk_set_rate(struct clk *clk, unsigned long rate)
+{
+ int ret;
+
+ if (IS_ERR(clk))
+ return -EINVAL;
+
+ /* We do not default just do a clk->rate = rate as
+ * the clock may have been made this way by choice.
+ */
+
+ WARN_ON(clk->set_rate == NULL);
+
+ if (clk->set_rate == NULL)
+ return -EINVAL;
+
+ spin_lock(&clocks_lock);
+ ret = (clk->set_rate)(clk, rate);
+ spin_unlock(&clocks_lock);
+
+ return ret;
+}
+
+struct clk *clk_get_parent(struct clk *clk)
+{
+ return clk->parent;
+}
+
+int clk_set_parent(struct clk *clk, struct clk *parent)
+{
+ int ret = 0;
+
+ if (IS_ERR(clk))
+ return -EINVAL;
+
+ spin_lock(&clocks_lock);
+
+ if (clk->set_parent)
+ ret = (clk->set_parent)(clk, parent);
+
+ spin_unlock(&clocks_lock);
+
+ return ret;
+}
+
+EXPORT_SYMBOL(clk_get);
+EXPORT_SYMBOL(clk_put);
+EXPORT_SYMBOL(clk_enable);
+EXPORT_SYMBOL(clk_disable);
+EXPORT_SYMBOL(clk_get_rate);
+EXPORT_SYMBOL(clk_round_rate);
+EXPORT_SYMBOL(clk_set_rate);
+EXPORT_SYMBOL(clk_get_parent);
+EXPORT_SYMBOL(clk_set_parent);
+
+/* base clocks */
+
+static int clk_default_setrate(struct clk *clk, unsigned long rate)
+{
+ clk->rate = rate;
+ return 0;
+}
+
+struct clk clk_xtal = {
+ .name = "xtal",
+ .id = -1,
+ .rate = 0,
+ .parent = NULL,
+ .ctrlbit = 0,
+};
+
+struct clk clk_ext = {
+ .name = "ext",
+ .id = -1,
+};
+
+struct clk clk_epll = {
+ .name = "epll",
+ .id = -1,
+};
+
+struct clk clk_mpll = {
+ .name = "mpll",
+ .id = -1,
+ .set_rate = clk_default_setrate,
+};
+
+struct clk clk_upll = {
+ .name = "upll",
+ .id = -1,
+ .parent = NULL,
+ .ctrlbit = 0,
+};
+
+struct clk clk_f = {
+ .name = "fclk",
+ .id = -1,
+ .rate = 0,
+ .parent = &clk_mpll,
+ .ctrlbit = 0,
+ .set_rate = clk_default_setrate,
+};
+
+struct clk clk_h = {
+ .name = "hclk",
+ .id = -1,
+ .rate = 0,
+ .parent = NULL,
+ .ctrlbit = 0,
+ .set_rate = clk_default_setrate,
+};
+
+struct clk clk_p = {
+ .name = "pclk",
+ .id = -1,
+ .rate = 0,
+ .parent = NULL,
+ .ctrlbit = 0,
+ .set_rate = clk_default_setrate,
+};
+
+struct clk clk_usb_bus = {
+ .name = "usb-bus",
+ .id = -1,
+ .rate = 0,
+ .parent = &clk_upll,
+};
+
+
+
+struct clk s3c24xx_uclk = {
+ .name = "uclk",
+ .id = -1,
+};
+
+/* initialise the clock system */
+
+int s3c24xx_register_clock(struct clk *clk)
+{
+ clk->owner = THIS_MODULE;
+
+ if (clk->enable == NULL)
+ clk->enable = clk_null_enable;
+
+ /* add to the list of available clocks */
+
+ /* Quick check to see if this clock has already been registered. */
+ BUG_ON(clk->list.prev != clk->list.next);
+
+ spin_lock(&clocks_lock);
+ list_add(&clk->list, &clocks);
+ spin_unlock(&clocks_lock);
+
+ return 0;
+}
+
+int s3c24xx_register_clocks(struct clk **clks, int nr_clks)
+{
+ int fails = 0;
+
+ for (; nr_clks > 0; nr_clks--, clks++) {
+ if (s3c24xx_register_clock(*clks) < 0)
+ fails++;
+ }
+
+ return fails;
+}
+
+/* initalise all the clocks */
+
+int __init s3c24xx_register_baseclocks(unsigned long xtal)
+{
+ printk(KERN_INFO "S3C24XX Clocks, (c) 2004 Simtec Electronics\n");
+
+ clk_xtal.rate = xtal;
+
+ /* register our clocks */
+
+ if (s3c24xx_register_clock(&clk_xtal) < 0)
+ printk(KERN_ERR "failed to register master xtal\n");
+
+ if (s3c24xx_register_clock(&clk_mpll) < 0)
+ printk(KERN_ERR "failed to register mpll clock\n");
+
+ if (s3c24xx_register_clock(&clk_upll) < 0)
+ printk(KERN_ERR "failed to register upll clock\n");
+
+ if (s3c24xx_register_clock(&clk_f) < 0)
+ printk(KERN_ERR "failed to register cpu fclk\n");
+
+ if (s3c24xx_register_clock(&clk_h) < 0)
+ printk(KERN_ERR "failed to register cpu hclk\n");
+
+ if (s3c24xx_register_clock(&clk_p) < 0)
+ printk(KERN_ERR "failed to register cpu pclk\n");
+
+ return 0;
+}
+