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Diffstat (limited to 'arch/arm/plat-s3c24xx/clock-dclk.c')
-rw-r--r--arch/arm/plat-s3c24xx/clock-dclk.c194
1 files changed, 194 insertions, 0 deletions
diff --git a/arch/arm/plat-s3c24xx/clock-dclk.c b/arch/arm/plat-s3c24xx/clock-dclk.c
new file mode 100644
index 000000000000..5b75a797b5ab
--- /dev/null
+++ b/arch/arm/plat-s3c24xx/clock-dclk.c
@@ -0,0 +1,194 @@
+/* linux/arch/arm/plat-s3c24xx/clock-dclk.c
+ *
+ * Copyright (c) 2004,2008 Simtec Electronics
+ * Ben Dooks <ben@simtec.co.uk>
+ * http://armlinux.simtec.co.uk/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * S3C24XX - definitions for DCLK and CLKOUT registers
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+
+#include <mach/regs-clock.h>
+#include <mach/regs-gpio.h>
+
+#include <plat/clock.h>
+#include <plat/cpu.h>
+
+/* 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 unsigned long s3c24xx_calc_div(struct clk *clk, unsigned long rate)
+{
+ unsigned long div;
+
+ if ((rate == 0) || !clk->parent)
+ return 0;
+
+ div = clk_get_rate(clk->parent) / rate;
+ if (div < 2)
+ div = 2;
+ else if (div > 16)
+ div = 16;
+
+ return div;
+}
+
+static unsigned long s3c24xx_round_dclk_rate(struct clk *clk,
+ unsigned long rate)
+{
+ unsigned long div = s3c24xx_calc_div(clk, rate);
+
+ if (div == 0)
+ return 0;
+
+ return clk_get_rate(clk->parent) / div;
+}
+
+static int s3c24xx_set_dclk_rate(struct clk *clk, unsigned long rate)
+{
+ unsigned long mask, data, div = s3c24xx_calc_div(clk, rate);
+
+ if (div == 0)
+ return -EINVAL;
+
+ if (clk == &s3c24xx_dclk0) {
+ mask = S3C2410_DCLKCON_DCLK0_DIV_MASK |
+ S3C2410_DCLKCON_DCLK0_CMP_MASK;
+ data = S3C2410_DCLKCON_DCLK0_DIV(div) |
+ S3C2410_DCLKCON_DCLK0_CMP((div + 1) / 2);
+ } else if (clk == &s3c24xx_dclk1) {
+ mask = S3C2410_DCLKCON_DCLK1_DIV_MASK |
+ S3C2410_DCLKCON_DCLK1_CMP_MASK;
+ data = S3C2410_DCLKCON_DCLK1_DIV(div) |
+ S3C2410_DCLKCON_DCLK1_CMP((div + 1) / 2);
+ } else
+ return -EINVAL;
+
+ clk->rate = clk_get_rate(clk->parent) / div;
+ __raw_writel(((__raw_readl(S3C24XX_DCLKCON) & ~mask) | data),
+ S3C24XX_DCLKCON);
+ return clk->rate;
+}
+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_clkout0)
+ 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,
+ .set_rate = s3c24xx_set_dclk_rate,
+ .round_rate = s3c24xx_round_dclk_rate,
+};
+
+struct clk s3c24xx_dclk1 = {
+ .name = "dclk1",
+ .id = -1,
+ .ctrlbit = S3C2410_DCLKCON_DCLK1EN,
+ .enable = s3c24xx_dclk_enable,
+ .set_parent = s3c24xx_dclk_setparent,
+ .set_rate = s3c24xx_set_dclk_rate,
+ .round_rate = s3c24xx_round_dclk_rate,
+};
+
+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,
+};