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-rw-r--r--arch/arm/plat-s3c24xx/clock.c449
1 files changed, 449 insertions, 0 deletions
diff --git a/arch/arm/plat-s3c24xx/clock.c b/arch/arm/plat-s3c24xx/clock.c
new file mode 100644
index 000000000000..d3dc03a7383a
--- /dev/null
+++ b/arch/arm/plat-s3c24xx/clock.c
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+/* 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/mutex.h>
+#include <linux/delay.h>
+
+#include <asm/hardware.h>
+#include <asm/irq.h>
+#include <asm/io.h>
+
+#include <asm/arch/regs-clock.h>
+#include <asm/arch/regs-gpio.h>
+
+#include <asm/plat-s3c24xx/clock.h>
+#include <asm/plat-s3c24xx/cpu.h>
+
+/* clock information */
+
+static LIST_HEAD(clocks);
+
+DEFINE_MUTEX(clocks_mutex);
+
+/* 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;
+
+ mutex_lock(&clocks_mutex);
+
+ 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;
+ }
+ }
+ }
+
+ mutex_unlock(&clocks_mutex);
+ 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);
+
+ mutex_lock(&clocks_mutex);
+
+ if ((clk->usage++) == 0)
+ (clk->enable)(clk, 1);
+
+ mutex_unlock(&clocks_mutex);
+ return 0;
+}
+
+void clk_disable(struct clk *clk)
+{
+ if (IS_ERR(clk) || clk == NULL)
+ return;
+
+ mutex_lock(&clocks_mutex);
+
+ if ((--clk->usage) == 0)
+ (clk->enable)(clk, 0);
+
+ mutex_unlock(&clocks_mutex);
+ 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;
+
+ mutex_lock(&clocks_mutex);
+ ret = (clk->set_rate)(clk, rate);
+ mutex_unlock(&clocks_mutex);
+
+ 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;
+
+ mutex_lock(&clocks_mutex);
+
+ if (clk->set_parent)
+ ret = (clk->set_parent)(clk, parent);
+
+ mutex_unlock(&clocks_mutex);
+
+ 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 */
+
+struct clk clk_xtal = {
+ .name = "xtal",
+ .id = -1,
+ .rate = 0,
+ .parent = NULL,
+ .ctrlbit = 0,
+};
+
+struct clk clk_mpll = {
+ .name = "mpll",
+ .id = -1,
+};
+
+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,
+};
+
+struct clk clk_h = {
+ .name = "hclk",
+ .id = -1,
+ .rate = 0,
+ .parent = NULL,
+ .ctrlbit = 0,
+};
+
+struct clk clk_p = {
+ .name = "pclk",
+ .id = -1,
+ .rate = 0,
+ .parent = NULL,
+ .ctrlbit = 0,
+};
+
+struct clk clk_usb_bus = {
+ .name = "usb-bus",
+ .id = -1,
+ .rate = 0,
+ .parent = &clk_upll,
+};
+
+/* clocks that could be registered by external code */
+
+static int s3c24xx_dclk_enable(struct clk *clk, int enable)
+{
+ unsigned long dclkcon = __raw_readl(S3C24XX_DCLKCON);
+
+ if (enable)
+ dclkcon |= clk->ctrlbit;
+ else
+ dclkcon &= ~clk->ctrlbit;
+
+ __raw_writel(dclkcon, S3C24XX_DCLKCON);
+
+ return 0;
+}
+
+static int s3c24xx_dclk_setparent(struct clk *clk, struct clk *parent)
+{
+ unsigned long dclkcon;
+ unsigned int uclk;
+
+ if (parent == &clk_upll)
+ uclk = 1;
+ else if (parent == &clk_p)
+ uclk = 0;
+ else
+ return -EINVAL;
+
+ clk->parent = parent;
+
+ dclkcon = __raw_readl(S3C24XX_DCLKCON);
+
+ if (clk->ctrlbit == S3C2410_DCLKCON_DCLK0EN) {
+ if (uclk)
+ dclkcon |= S3C2410_DCLKCON_DCLK0_UCLK;
+ else
+ dclkcon &= ~S3C2410_DCLKCON_DCLK0_UCLK;
+ } else {
+ if (uclk)
+ dclkcon |= S3C2410_DCLKCON_DCLK1_UCLK;
+ else
+ dclkcon &= ~S3C2410_DCLKCON_DCLK1_UCLK;
+ }
+
+ __raw_writel(dclkcon, S3C24XX_DCLKCON);
+
+ return 0;
+}
+
+
+static int s3c24xx_clkout_setparent(struct clk *clk, struct clk *parent)
+{
+ unsigned long mask;
+ unsigned long source;
+
+ /* calculate the MISCCR setting for the clock */
+
+ if (parent == &clk_xtal)
+ source = S3C2410_MISCCR_CLK0_MPLL;
+ else if (parent == &clk_upll)
+ source = S3C2410_MISCCR_CLK0_UPLL;
+ else if (parent == &clk_f)
+ source = S3C2410_MISCCR_CLK0_FCLK;
+ else if (parent == &clk_h)
+ source = S3C2410_MISCCR_CLK0_HCLK;
+ else if (parent == &clk_p)
+ source = S3C2410_MISCCR_CLK0_PCLK;
+ else if (clk == &s3c24xx_clkout0 && parent == &s3c24xx_dclk0)
+ source = S3C2410_MISCCR_CLK0_DCLK0;
+ else if (clk == &s3c24xx_clkout1 && parent == &s3c24xx_dclk1)
+ source = S3C2410_MISCCR_CLK0_DCLK0;
+ else
+ return -EINVAL;
+
+ clk->parent = parent;
+
+ if (clk == &s3c24xx_dclk0)
+ mask = S3C2410_MISCCR_CLK0_MASK;
+ else {
+ source <<= 4;
+ mask = S3C2410_MISCCR_CLK1_MASK;
+ }
+
+ s3c2410_modify_misccr(mask, source);
+ return 0;
+}
+
+/* external clock definitions */
+
+struct clk s3c24xx_dclk0 = {
+ .name = "dclk0",
+ .id = -1,
+ .ctrlbit = S3C2410_DCLKCON_DCLK0EN,
+ .enable = s3c24xx_dclk_enable,
+ .set_parent = s3c24xx_dclk_setparent,
+};
+
+struct clk s3c24xx_dclk1 = {
+ .name = "dclk1",
+ .id = -1,
+ .ctrlbit = S3C2410_DCLKCON_DCLK0EN,
+ .enable = s3c24xx_dclk_enable,
+ .set_parent = s3c24xx_dclk_setparent,
+};
+
+struct clk s3c24xx_clkout0 = {
+ .name = "clkout0",
+ .id = -1,
+ .set_parent = s3c24xx_clkout_setparent,
+};
+
+struct clk s3c24xx_clkout1 = {
+ .name = "clkout1",
+ .id = -1,
+ .set_parent = s3c24xx_clkout_setparent,
+};
+
+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 */
+
+ mutex_lock(&clocks_mutex);
+ list_add(&clk->list, &clocks);
+ mutex_unlock(&clocks_mutex);
+
+ return 0;
+}
+
+/* initalise all the clocks */
+
+int __init s3c24xx_setup_clocks(unsigned long xtal,
+ unsigned long fclk,
+ unsigned long hclk,
+ unsigned long pclk)
+{
+ printk(KERN_INFO "S3C24XX Clocks, (c) 2004 Simtec Electronics\n");
+
+ /* initialise the main system clocks */
+
+ clk_xtal.rate = xtal;
+ clk_upll.rate = s3c2410_get_pll(__raw_readl(S3C2410_UPLLCON), xtal);
+
+ clk_mpll.rate = fclk;
+ clk_h.rate = hclk;
+ clk_p.rate = pclk;
+ clk_f.rate = fclk;
+
+ /* assume uart clocks are correctly setup */
+
+ /* 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;
+}
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