MXC family: Add clock handling

Internal clock path handling for the mxc CPUs.

Changed against the original Freescale code (and against clocklib for example):
 - clock rate is always calculated whenever one ask for the current rate
   (means struct clk has no more a member called "rate"). So switching the PLL
   base frequency will propagate immediately to all other clocks that are
   depending on this frequency.

Signed-off-by: Juergen Beisert <j.beisert@pengutronix.de>

1 files changed, 67 insertions, 0 deletions

diff --git a/include/asm-arm/arch-mxc/clock.h b/include/asm-arm/arch-mxc/clock.h
new file mode 100644
index 000000000000..24caa2b7c91d
--- /dev/null
+++ b/include/asm-arm/arch-mxc/clock.h
@@ -0,0 +1,67 @@
+/*
+ * Copyright 2005-2007 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright 2008 Juergen Beisert, kernel@pengutronix.de
+ *
+ * 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., 51 Franklin Street, Fifth Floor, Boston,
+ * MA  02110-1301, USA.
+ */
+
+#ifndef __ASM_ARCH_MXC_CLOCK_H__
+#define __ASM_ARCH_MXC_CLOCK_H__
+
+#ifndef __ASSEMBLY__
+#include <linux/list.h>
+
+struct module;
+
+struct clk {
+	struct list_head node;
+	struct module *owner;
+	const char *name;
+	int id;
+	/* Source clock this clk depends on */
+	struct clk *parent;
+	/* Secondary clock to enable/disable with this clock */
+	struct clk *secondary;
+	/* Reference count of clock enable/disable */
+	__s8 usecount;
+	/* Register bit position for clock's enable/disable control. */
+	u8 enable_shift;
+	/* Register address for clock's enable/disable control. */
+	u32 enable_reg;
+	u32 flags;
+	/* get the current clock rate (always a fresh value) */
+	unsigned long (*get_rate) (struct clk *);
+	/* Function ptr to set the clock to a new rate. The rate must match a
+	   supported rate returned from round_rate. Leave blank if clock is not
+	   programmable */
+	int (*set_rate) (struct clk *, unsigned long);
+	/* Function ptr to round the requested clock rate to the nearest
+	   supported rate that is less than or equal to the requested rate. */
+	unsigned long (*round_rate) (struct clk *, unsigned long);
+	/* Function ptr to enable the clock. Leave blank if clock can not
+	   be gated. */
+	int (*enable) (struct clk *);
+	/* Function ptr to disable the clock. Leave blank if clock can not
+	   be gated. */
+	void (*disable) (struct clk *);
+	/* Function ptr to set the parent clock of the clock. */
+	int (*set_parent) (struct clk *, struct clk *);
+};
+
+int clk_register(struct clk *clk);
+void clk_unregister(struct clk *clk);
+
+#endif /* __ASSEMBLY__ */
+#endif /* __ASM_ARCH_MXC_CLOCK_H__ */