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Diffstat (limited to 'arch/arm/plat-s3c24xx/s3c2443-clock.c')
-rw-r--r--arch/arm/plat-s3c24xx/s3c2443-clock.c87
1 files changed, 87 insertions, 0 deletions
diff --git a/arch/arm/plat-s3c24xx/s3c2443-clock.c b/arch/arm/plat-s3c24xx/s3c2443-clock.c
index 3f2117b8c0d4..f9c5b0343cf3 100644
--- a/arch/arm/plat-s3c24xx/s3c2443-clock.c
+++ b/arch/arm/plat-s3c24xx/s3c2443-clock.c
@@ -160,10 +160,95 @@ static struct clk clk_prediv = {
},
};
+/* armdiv
+ *
+ * this clock is sourced from msysclk and can have a number of
+ * divider values applied to it to then be fed into armclk.
+*/
+
static unsigned int *armdiv;
static int nr_armdiv;
static int armdivmask;
+static unsigned long s3c2443_armclk_roundrate(struct clk *clk,
+ unsigned long rate)
+{
+ unsigned long parent = clk_get_rate(clk->parent);
+ unsigned long calc;
+ unsigned best = 256; /* bigger than any value */
+ unsigned div;
+ int ptr;
+
+ for (ptr = 0; ptr < nr_armdiv; ptr++) {
+ div = armdiv[ptr];
+ calc = parent / div;
+ if (calc <= rate && div < best)
+ best = div;
+ }
+
+ return parent / best;
+}
+
+static int s3c2443_armclk_setrate(struct clk *clk, unsigned long rate)
+{
+ unsigned long parent = clk_get_rate(clk->parent);
+ unsigned long calc;
+ unsigned div;
+ unsigned best = 256; /* bigger than any value */
+ int ptr;
+ int val = -1;
+
+ for (ptr = 0; ptr < nr_armdiv; ptr++) {
+ div = armdiv[ptr];
+ calc = parent / div;
+ if (calc <= rate && div < best) {
+ best = div;
+ val = ptr;
+ }
+ }
+
+ if (val >= 0) {
+ unsigned long clkcon0;
+
+ clkcon0 = __raw_readl(S3C2443_CLKDIV0);
+ clkcon0 &= ~armdivmask;
+ clkcon0 |= val << S3C2443_CLKDIV0_ARMDIV_SHIFT;
+ __raw_writel(clkcon0, S3C2443_CLKDIV0);
+ }
+
+ return (val == -1) ? -EINVAL : 0;
+}
+
+static struct clk clk_armdiv = {
+ .name = "armdiv",
+ .parent = &clk_msysclk.clk,
+ .ops = &(struct clk_ops) {
+ .round_rate = s3c2443_armclk_roundrate,
+ .set_rate = s3c2443_armclk_setrate,
+ },
+};
+
+/* armclk
+ *
+ * this is the clock fed into the ARM core itself, from armdiv or from hclk.
+ */
+
+static struct clk *clk_arm_sources[] = {
+ [0] = &clk_armdiv,
+ [1] = &clk_h,
+};
+
+static struct clksrc_clk clk_arm = {
+ .clk = {
+ .name = "armclk",
+ },
+ .sources = &(struct clksrc_sources) {
+ .sources = clk_arm_sources,
+ .nr_sources = ARRAY_SIZE(clk_arm_sources),
+ },
+ .reg_src = { .reg = S3C2443_CLKDIV0, .size = 1, .shift = 13 },
+};
+
/* usbhost
*
* usb host bus-clock, usually 48MHz to provide USB bus clock timing
@@ -462,6 +547,7 @@ static struct clk *clks[] __initdata = {
&clk_ext,
&clk_epll,
&clk_usb_bus,
+ &clk_armdiv,
};
static struct clksrc_clk *clksrcs[] __initdata = {
@@ -471,6 +557,7 @@ static struct clksrc_clk *clksrcs[] __initdata = {
&clk_epllref,
&clk_esysclk,
&clk_msysclk,
+ &clk_arm,
};
void __init s3c2443_common_init_clocks(int xtal, pll_fn get_mpll,