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Diffstat (limited to 'arch/arm/mach-s3c2410/s3c2410-clock.c')
-rw-r--r--arch/arm/mach-s3c2410/s3c2410-clock.c263
1 files changed, 263 insertions, 0 deletions
diff --git a/arch/arm/mach-s3c2410/s3c2410-clock.c b/arch/arm/mach-s3c2410/s3c2410-clock.c
new file mode 100644
index 0000000..fd17c60
--- /dev/null
+++ b/arch/arm/mach-s3c2410/s3c2410-clock.c
@@ -0,0 +1,263 @@
+/* linux/arch/arm/mach-s3c2410/clock.c
+ *
+ * Copyright (c) 2006 Simtec Electronics
+ * Ben Dooks <ben@simtec.co.uk>
+ *
+ * S3C2410,S3C2440,S3C2442 Clock control 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/sysdev.h>
+#include <linux/clk.h>
+#include <linux/mutex.h>
+#include <linux/delay.h>
+
+#include <asm/hardware.h>
+#include <asm/io.h>
+
+#include <asm/arch/regs-clock.h>
+#include <asm/arch/regs-gpio.h>
+
+#include "clock.h"
+#include "cpu.h"
+
+int s3c2410_clkcon_enable(struct clk *clk, int enable)
+{
+ unsigned int clocks = clk->ctrlbit;
+ unsigned long clkcon;
+
+ clkcon = __raw_readl(S3C2410_CLKCON);
+
+ if (enable)
+ clkcon |= clocks;
+ else
+ clkcon &= ~clocks;
+
+ /* ensure none of the special function bits set */
+ clkcon &= ~(S3C2410_CLKCON_IDLE|S3C2410_CLKCON_POWER);
+
+ __raw_writel(clkcon, S3C2410_CLKCON);
+
+ return 0;
+}
+
+static int s3c2410_upll_enable(struct clk *clk, int enable)
+{
+ unsigned long clkslow = __raw_readl(S3C2410_CLKSLOW);
+ unsigned long orig = clkslow;
+
+ if (enable)
+ clkslow &= ~S3C2410_CLKSLOW_UCLK_OFF;
+ else
+ clkslow |= S3C2410_CLKSLOW_UCLK_OFF;
+
+ __raw_writel(clkslow, S3C2410_CLKSLOW);
+
+ /* if we started the UPLL, then allow to settle */
+
+ if (enable && (orig & S3C2410_CLKSLOW_UCLK_OFF))
+ udelay(200);
+
+ return 0;
+}
+
+/* standard clock definitions */
+
+static struct clk init_clocks_disable[] = {
+ {
+ .name = "nand",
+ .id = -1,
+ .parent = &clk_h,
+ .enable = s3c2410_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_NAND,
+ }, {
+ .name = "sdi",
+ .id = -1,
+ .parent = &clk_p,
+ .enable = s3c2410_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_SDI,
+ }, {
+ .name = "adc",
+ .id = -1,
+ .parent = &clk_p,
+ .enable = s3c2410_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_ADC,
+ }, {
+ .name = "i2c",
+ .id = -1,
+ .parent = &clk_p,
+ .enable = s3c2410_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_IIC,
+ }, {
+ .name = "iis",
+ .id = -1,
+ .parent = &clk_p,
+ .enable = s3c2410_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_IIS,
+ }, {
+ .name = "spi",
+ .id = -1,
+ .parent = &clk_p,
+ .enable = s3c2410_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_SPI,
+ }
+};
+
+static struct clk init_clocks[] = {
+ {
+ .name = "lcd",
+ .id = -1,
+ .parent = &clk_h,
+ .enable = s3c2410_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_LCDC,
+ }, {
+ .name = "gpio",
+ .id = -1,
+ .parent = &clk_p,
+ .enable = s3c2410_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_GPIO,
+ }, {
+ .name = "usb-host",
+ .id = -1,
+ .parent = &clk_h,
+ .enable = s3c2410_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_USBH,
+ }, {
+ .name = "usb-device",
+ .id = -1,
+ .parent = &clk_h,
+ .enable = s3c2410_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_USBD,
+ }, {
+ .name = "timers",
+ .id = -1,
+ .parent = &clk_p,
+ .enable = s3c2410_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_PWMT,
+ }, {
+ .name = "uart",
+ .id = 0,
+ .parent = &clk_p,
+ .enable = s3c2410_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_UART0,
+ }, {
+ .name = "uart",
+ .id = 1,
+ .parent = &clk_p,
+ .enable = s3c2410_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_UART1,
+ }, {
+ .name = "uart",
+ .id = 2,
+ .parent = &clk_p,
+ .enable = s3c2410_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_UART2,
+ }, {
+ .name = "rtc",
+ .id = -1,
+ .parent = &clk_p,
+ .enable = s3c2410_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_RTC,
+ }, {
+ .name = "watchdog",
+ .id = -1,
+ .parent = &clk_p,
+ .ctrlbit = 0,
+ }
+};
+
+/* s3c2410_baseclk_add()
+ *
+ * Add all the clocks used by the s3c2410 or compatible CPUs
+ * such as the S3C2440 and S3C2442.
+ *
+ * We cannot use a system device as we are needed before any
+ * of the init-calls that initialise the devices are actually
+ * done.
+*/
+
+int __init s3c2410_baseclk_add(void)
+{
+ unsigned long clkslow = __raw_readl(S3C2410_CLKSLOW);
+ unsigned long clkcon = __raw_readl(S3C2410_CLKCON);
+ struct clk *clkp;
+ struct clk *xtal;
+ int ret;
+ int ptr;
+
+ clk_upll.enable = s3c2410_upll_enable;
+
+ if (s3c24xx_register_clock(&clk_usb_bus) < 0)
+ printk(KERN_ERR "failed to register usb bus clock\n");
+
+ /* register clocks from clock array */
+
+ clkp = init_clocks;
+ for (ptr = 0; ptr < ARRAY_SIZE(init_clocks); ptr++, clkp++) {
+ /* ensure that we note the clock state */
+
+ clkp->usage = clkcon & clkp->ctrlbit ? 1 : 0;
+
+ ret = s3c24xx_register_clock(clkp);
+ if (ret < 0) {
+ printk(KERN_ERR "Failed to register clock %s (%d)\n",
+ clkp->name, ret);
+ }
+ }
+
+ /* We must be careful disabling the clocks we are not intending to
+ * be using at boot time, as subsytems such as the LCD which do
+ * their own DMA requests to the bus can cause the system to lockup
+ * if they where in the middle of requesting bus access.
+ *
+ * Disabling the LCD clock if the LCD is active is very dangerous,
+ * and therefore the bootloader should be careful to not enable
+ * the LCD clock if it is not needed.
+ */
+
+ /* install (and disable) the clocks we do not need immediately */
+
+ clkp = init_clocks_disable;
+ for (ptr = 0; ptr < ARRAY_SIZE(init_clocks_disable); ptr++, clkp++) {
+
+ ret = s3c24xx_register_clock(clkp);
+ if (ret < 0) {
+ printk(KERN_ERR "Failed to register clock %s (%d)\n",
+ clkp->name, ret);
+ }
+
+ s3c2410_clkcon_enable(clkp, 0);
+ }
+
+ /* show the clock-slow value */
+
+ xtal = clk_get(NULL, "xtal");
+
+ printk("CLOCK: Slow mode (%ld.%ld MHz), %s, MPLL %s, UPLL %s\n",
+ print_mhz(clk_get_rate(xtal) /
+ ( 2 * S3C2410_CLKSLOW_GET_SLOWVAL(clkslow))),
+ (clkslow & S3C2410_CLKSLOW_SLOW) ? "slow" : "fast",
+ (clkslow & S3C2410_CLKSLOW_MPLL_OFF) ? "off" : "on",
+ (clkslow & S3C2410_CLKSLOW_UCLK_OFF) ? "off" : "on");
+
+ return 0;
+}
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