[PATCH] sh: Simplistic clock framework

This adds a relatively simplistic clock framework for sh.  The initial goal
behind this is to clean up the arch/sh/kernel/time.c mess and to get the CPU
subtype-specific frequency setting and calculation code moved somewhere more
sensible.

This only deals with the core clocks at the moment, though it's trivial for
other drivers to define their own clocks as desired.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 96 insertions, 0 deletions

diff --git a/arch/sh/kernel/cpu/sh3/clock-sh7709.c b/arch/sh/kernel/cpu/sh3/clock-sh7709.c
new file mode 100644
index 00000000000..10461a745e5
--- /dev/null
+++ b/arch/sh/kernel/cpu/sh3/clock-sh7709.c
@@ -0,0 +1,96 @@
+/*
+ * arch/sh/kernel/cpu/sh3/clock-sh7709.c
+ *
+ * SH7709 support for the clock framework
+ *
+ *  Copyright (C) 2005  Andriy Skulysh
+ *
+ * Based on arch/sh/kernel/cpu/sh3/clock-sh7705.c
+ *  Copyright (C) 2005  Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <asm/clock.h>
+#include <asm/freq.h>
+#include <asm/io.h>
+
+static int stc_multipliers[] = { 1, 2, 4, 8, 3, 6, 1, 1 };
+static int ifc_divisors[]    = { 1, 2, 4, 1, 3, 1, 1, 1 };
+static int pfc_divisors[]    = { 1, 2, 4, 1, 3, 6, 1, 1 };
+
+static void set_bus_parent(struct clk *clk)
+{
+	struct clk *bus_clk = clk_get("bus_clk");
+	clk->parent = bus_clk;
+	clk_put(bus_clk);
+}
+
+static void master_clk_init(struct clk *clk)
+{
+	int frqcr = ctrl_inw(FRQCR);
+	int idx = ((frqcr & 0x2000) >> 11) | (frqcr & 0x0003);
+
+	clk->rate *= pfc_divisors[idx];
+}
+
+static struct clk_ops sh7709_master_clk_ops = {
+	.init		= master_clk_init,
+};
+
+static void module_clk_recalc(struct clk *clk)
+{
+	int frqcr = ctrl_inw(FRQCR);
+	int idx = ((frqcr & 0x2000) >> 11) | (frqcr & 0x0003);
+
+	clk->rate = clk->parent->rate / pfc_divisors[idx];
+}
+
+static struct clk_ops sh7709_module_clk_ops = {
+#ifdef CLOCK_MODE_0_1_2_7
+	.init		= set_bus_parent,
+#endif
+	.recalc		= module_clk_recalc,
+};
+
+static void bus_clk_recalc(struct clk *clk)
+{
+	int frqcr = ctrl_inw(FRQCR);
+	int idx = (frqcr & 0x0080) ?
+		((frqcr & 0x8000) >> 13) | ((frqcr & 0x0030) >> 4) : 1;
+
+	clk->rate = clk->parent->rate * stc_multipliers[idx];
+}
+
+static struct clk_ops sh7709_bus_clk_ops = {
+	.recalc		= bus_clk_recalc,
+};
+
+static void cpu_clk_recalc(struct clk *clk)
+{
+	int frqcr = ctrl_inw(FRQCR);
+	int idx = ((frqcr & 0x4000) >> 12) | ((frqcr & 0x000c) >> 2);
+
+	clk->rate = clk->parent->rate / ifc_divisors[idx];
+}
+
+static struct clk_ops sh7709_cpu_clk_ops = {
+	.init		= set_bus_parent,
+	.recalc		= cpu_clk_recalc,
+};
+
+static struct clk_ops *sh7709_clk_ops[] = {
+	&sh7709_master_clk_ops,
+	&sh7709_module_clk_ops,
+	&sh7709_bus_clk_ops,
+	&sh7709_cpu_clk_ops,
+};
+
+void __init arch_init_clk_ops(struct clk_ops **ops, int idx)
+{
+	if (idx < ARRAY_SIZE(sh7709_clk_ops))
+		*ops = sh7709_clk_ops[idx];
+}