This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / arch / arm / mach-s3c2410 / s3c2442-clock.c

diff --git a/arch/arm/mach-s3c2410/s3c2442-clock.c b/arch/arm/mach-s3c2410/s3c2442-clock.c
new file mode 100644 (file)
index 0000000..d9f54b5
--- /dev/null
+++ b/arch/arm/mach-s3c2410/s3c2442-clock.c
@@ -0,0 +1,171 @@
+/* linux/arch/arm/mach-s3c2410/s3c2442-clock.c
+ *
+ * Copyright (c) 2004-2005 Simtec Electronics
+ *     http://armlinux.simtec.co.uk/
+ *     Ben Dooks <ben@simtec.co.uk>
+ *
+ * S3C2442 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 "clock.h"
+#include "cpu.h"
+
+/* S3C2442 extended clock support */
+
+static unsigned long s3c2442_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;
+
+       div = parent_rate / rate;
+
+       if (div == 3)
+               return parent_rate / 3;
+
+       /* note, we remove the +/- 1 calculations for the divisor */
+
+       div /= 2;
+
+       if (div < 1)
+               div = 1;
+       else if (div > 16)
+               div = 16;
+
+       return parent_rate / (div * 2);
+}
+
+static int s3c2442_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 = s3c2442_camif_upll_round(clk, rate);
+
+       camdivn &= ~S3C2442_CAMDIVN_CAMCLK_DIV3;
+
+       if (rate == parent_rate) {
+               camdivn &= ~S3C2440_CAMDIVN_CAMCLK_SEL;
+       } else if ((parent_rate / rate) == 3) {
+               camdivn |= S3C2440_CAMDIVN_CAMCLK_SEL;
+               camdivn |= S3C2442_CAMDIVN_CAMCLK_DIV3;
+       } else {
+               camdivn &= ~S3C2440_CAMDIVN_CAMCLK_MASK;
+               camdivn |= S3C2440_CAMDIVN_CAMCLK_SEL;
+               camdivn |= (((parent_rate / rate) / 2) - 1);
+       }
+
+       __raw_writel(camdivn, S3C2440_CAMDIVN);
+
+       return 0;
+}
+
+/* Extra S3C2442 clocks */
+
+static struct clk s3c2442_clk_cam = {
+       .name           = "camif",
+       .id             = -1,
+       .enable         = s3c2410_clkcon_enable,
+       .ctrlbit        = S3C2440_CLKCON_CAMERA,
+};
+
+static struct clk s3c2442_clk_cam_upll = {
+       .name           = "camif-upll",
+       .id             = -1,
+       .set_rate       = s3c2442_camif_upll_setrate,
+       .round_rate     = s3c2442_camif_upll_round,
+};
+
+static int s3c2442_clk_add(struct sys_device *sysdev)
+{
+       unsigned long camdivn = __raw_readl(S3C2440_CAMDIVN);
+       unsigned long clkdivn;
+       struct clk *clk_h;
+       struct clk *clk_p;
+       struct clk *clk_upll;
+
+       printk("S3C2442: Clock Support, DVS %s\n",
+              (camdivn & S3C2440_CAMDIVN_DVSEN) ? "on" : "off");
+
+       clk_p = clk_get(NULL, "pclk");
+       clk_h = clk_get(NULL, "hclk");
+       clk_upll = clk_get(NULL, "upll");
+
+       if (IS_ERR(clk_p) || IS_ERR(clk_h) || IS_ERR(clk_upll)) {
+               printk(KERN_ERR "S3C2442: Failed to get parent clocks\n");
+               return -EINVAL;
+       }
+
+       /* 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(clk_upll) > (94 * MHZ)) {
+               clk_usb_bus.rate = clk_get_rate(clk_upll) / 2;
+
+               mutex_lock(&clocks_mutex);
+
+               clkdivn = __raw_readl(S3C2410_CLKDIVN);
+               clkdivn |= S3C2440_CLKDIVN_UCLK;
+               __raw_writel(clkdivn, S3C2410_CLKDIVN);
+
+               mutex_unlock(&clocks_mutex);
+       }
+
+       s3c2442_clk_cam.parent = clk_h;
+       s3c2442_clk_cam_upll.parent = clk_upll;
+
+       s3c24xx_register_clock(&s3c2442_clk_cam);
+       s3c24xx_register_clock(&s3c2442_clk_cam_upll);
+
+       clk_disable(&s3c2442_clk_cam);
+
+       return 0;
+}
+
+static struct sysdev_driver s3c2442_clk_driver = {
+       .add    = s3c2442_clk_add,
+};
+
+static __init int s3c2442_clk_init(void)
+{
+       return sysdev_driver_register(&s3c2442_sysclass, &s3c2442_clk_driver);
+}
+
+arch_initcall(s3c2442_clk_init);