ARM: S3C2443: Add set_rate and round_rate calls for armdiv clock

Add set_rate and round_rate calls to armdiv for future use with cpu
frequency scaling.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>

1 files changed, 73 insertions, 20 deletions

diff --git a/arch/arm/mach-s3c2443/clock.c b/arch/arm/mach-s3c2443/clock.c
index 177719c7c267..62cd4eaee01b 100644
--- a/arch/arm/mach-s3c2443/clock.c
+++ b/arch/arm/mach-s3c2443/clock.c
@@ -165,10 +165,83 @@ static struct clksrc_clk clk_msysclk = {
  * divider values applied to it to then be fed into armclk.
 */
 
+/* armdiv divisor table */
+
+static unsigned int armdiv[16] = {
+        [S3C2443_CLKDIV0_ARMDIV_1 >> S3C2443_CLKDIV0_ARMDIV_SHIFT]      = 1,
+        [S3C2443_CLKDIV0_ARMDIV_2 >> S3C2443_CLKDIV0_ARMDIV_SHIFT]      = 2,
+        [S3C2443_CLKDIV0_ARMDIV_3 >> S3C2443_CLKDIV0_ARMDIV_SHIFT]      = 3,
+        [S3C2443_CLKDIV0_ARMDIV_4 >> S3C2443_CLKDIV0_ARMDIV_SHIFT]      = 4,
+        [S3C2443_CLKDIV0_ARMDIV_6 >> S3C2443_CLKDIV0_ARMDIV_SHIFT]      = 6,
+        [S3C2443_CLKDIV0_ARMDIV_8 >> S3C2443_CLKDIV0_ARMDIV_SHIFT]      = 8,
+        [S3C2443_CLKDIV0_ARMDIV_12 >> S3C2443_CLKDIV0_ARMDIV_SHIFT]     = 12,
+        [S3C2443_CLKDIV0_ARMDIV_16 >> S3C2443_CLKDIV0_ARMDIV_SHIFT]     = 16,
+};
+
+static inline unsigned int s3c2443_fclk_div(unsigned long clkcon0)
+{
+        clkcon0 &= S3C2443_CLKDIV0_ARMDIV_MASK;
+
+        return armdiv[clkcon0 >> S3C2443_CLKDIV0_ARMDIV_SHIFT];
+}
+
+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 < ARRAY_SIZE(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 < ARRAY_SIZE(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 &= S3C2443_CLKDIV0_ARMDIV_MASK;
+                clkcon0 |= val << S3C2443_CLKDIV0_ARMDIV_SHIFT;
+                __raw_writel(clkcon0, S3C2443_CLKDIV0);
+        }
+
+        return (val == -1) ? -EINVAL : 0;
+}
+
 static struct clk clk_armdiv = {
         .name           = "armdiv",
         .id             = -1,
         .parent         = &clk_msysclk.clk,
+        .ops            = &(struct clk_ops) {
+                .round_rate = s3c2443_armclk_roundrate,
+                .set_rate = s3c2443_armclk_setrate,
+        },
 };
 
 /* armclk
@@ -619,26 +692,6 @@ static void __init s3c2443_clk_initparents(void)
                 s3c_set_clksrc(init_list[ptr], true);
 }
 
-/* armdiv divisor table */
-
-static unsigned int armdiv[16] = {
-        [S3C2443_CLKDIV0_ARMDIV_1 >> S3C2443_CLKDIV0_ARMDIV_SHIFT]      = 1,
-        [S3C2443_CLKDIV0_ARMDIV_2 >> S3C2443_CLKDIV0_ARMDIV_SHIFT]      = 2,
-        [S3C2443_CLKDIV0_ARMDIV_3 >> S3C2443_CLKDIV0_ARMDIV_SHIFT]      = 3,
-        [S3C2443_CLKDIV0_ARMDIV_4 >> S3C2443_CLKDIV0_ARMDIV_SHIFT]      = 4,
-        [S3C2443_CLKDIV0_ARMDIV_6 >> S3C2443_CLKDIV0_ARMDIV_SHIFT]      = 6,
-        [S3C2443_CLKDIV0_ARMDIV_8 >> S3C2443_CLKDIV0_ARMDIV_SHIFT]      = 8,
-        [S3C2443_CLKDIV0_ARMDIV_12 >> S3C2443_CLKDIV0_ARMDIV_SHIFT]     = 12,
-        [S3C2443_CLKDIV0_ARMDIV_16 >> S3C2443_CLKDIV0_ARMDIV_SHIFT]     = 16,
-};
-
-static inline unsigned int s3c2443_fclk_div(unsigned long clkcon0)
-{
-        clkcon0 &= S3C2443_CLKDIV0_ARMDIV_MASK;
-
-        return armdiv[clkcon0 >> S3C2443_CLKDIV0_ARMDIV_SHIFT];
-}
-
 static inline unsigned long s3c2443_get_hdiv(unsigned long clkcon0)
 {
         clkcon0 &= S3C2443_CLKDIV0_HCLKDIV_MASK;