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diff --git a/arch/arm/mach-ux500/clock.h b/arch/arm/mach-ux500/clock.h
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+/*
+ * Copyright (C) 2010 ST-Ericsson
+ * Copyright (C) 2009 STMicroelectronics
+ *
+ * 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.
+ */
+
+/**
+ * struct clkops - ux500 clock operations
+ * @enable: function to enable the clock
+ * @disable: function to disable the clock
+ * @get_rate: function to get the current clock rate
+ *
+ * This structure contains function pointers to functions that will be used to
+ * control the clock. All of these functions are optional. If get_rate is
+ * NULL, the rate in the struct clk will be used.
+ */
+struct clkops {
+ void (*enable) (struct clk *);
+ void (*disable) (struct clk *);
+ unsigned long (*get_rate) (struct clk *);
+};
+
+/**
+ * struct clk - ux500 clock structure
+ * @ops: pointer to clkops struct used to control this clock
+ * @name: name, for debugging
+ * @enabled: refcount. positive if enabled, zero if disabled
+ * @rate: fixed rate for clocks which don't implement
+ * ops->getrate
+ * @prcmu_cg_off: address offset of the combined enable/disable register
+ * (used on u8500v1)
+ * @prcmu_cg_bit: bit in the combined enable/disable register (used on
+ * u8500v1)
+ * @prcmu_cg_mgt: address of the enable/disable register (used on
+ * u8500ed)
+ * @cluster: peripheral cluster number
+ * @prcc_bus: bit for the bus clock in the peripheral's CLKRST
+ * @prcc_kernel: bit for the kernel clock in the peripheral's CLKRST.
+ * -1 if no kernel clock exists.
+ * @parent_cluster: pointer to parent's cluster clk struct
+ * @parent_periph: pointer to parent's peripheral clk struct
+ *
+ * Peripherals are organised into clusters, and each cluster has an associated
+ * bus clock. Some peripherals also have a parent peripheral clock.
+ *
+ * In order to enable a clock for a peripheral, we need to enable:
+ * (1) the parent cluster (bus) clock at the PRCMU level
+ * (2) the parent peripheral clock (if any) at the PRCMU level
+ * (3) the peripheral's bus & kernel clock at the PRCC level
+ *
+ * (1) and (2) are handled by defining clk structs (DEFINE_PRCMU_CLK) for each
+ * of the cluster and peripheral clocks, and hooking these as the parents of
+ * the individual peripheral clocks.
+ *
+ * (3) is handled by specifying the bits in the PRCC control registers required
+ * to enable these clocks and modifying them in the ->enable and
+ * ->disable callbacks of the peripheral clocks (DEFINE_PRCC_CLK).
+ *
+ * This structure describes both the PRCMU-level clocks and PRCC-level clocks.
+ * The prcmu_* fields are only used for the PRCMU clocks, and the cluster,
+ * prcc, and parent pointers are only used for the PRCC-level clocks.
+ */
+struct clk {
+ const struct clkops *ops;
+ const char *name;
+ unsigned int enabled;
+
+ unsigned long rate;
+ struct list_head list;
+
+ /* These three are only for PRCMU clks */
+
+ unsigned int prcmu_cg_off;
+ unsigned int prcmu_cg_bit;
+ unsigned int prcmu_cg_mgt;
+
+ /* The rest are only for PRCC clks */
+
+ int cluster;
+ unsigned int prcc_bus;
+ unsigned int prcc_kernel;
+
+ struct clk *parent_cluster;
+ struct clk *parent_periph;
+};
+
+#define DEFINE_PRCMU_CLK(_name, _cg_off, _cg_bit, _reg) \
+struct clk clk_##_name = { \
+ .name = #_name, \
+ .ops = &clk_prcmu_ops, \
+ .prcmu_cg_off = _cg_off, \
+ .prcmu_cg_bit = _cg_bit, \
+ .prcmu_cg_mgt = PRCM_##_reg##_MGT \
+ }
+
+#define DEFINE_PRCMU_CLK_RATE(_name, _cg_off, _cg_bit, _reg, _rate) \
+struct clk clk_##_name = { \
+ .name = #_name, \
+ .ops = &clk_prcmu_ops, \
+ .prcmu_cg_off = _cg_off, \
+ .prcmu_cg_bit = _cg_bit, \
+ .rate = _rate, \
+ .prcmu_cg_mgt = PRCM_##_reg##_MGT \
+ }
+
+#define DEFINE_PRCC_CLK(_pclust, _name, _bus_en, _kernel_en, _kernclk) \
+struct clk clk_##_name = { \
+ .name = #_name, \
+ .ops = &clk_prcc_ops, \
+ .cluster = _pclust, \
+ .prcc_bus = _bus_en, \
+ .prcc_kernel = _kernel_en, \
+ .parent_cluster = &clk_per##_pclust##clk, \
+ .parent_periph = _kernclk \
+ }
+
+#define CLK(_clk, _devname, _conname) \
+ { \
+ .clk = &clk_##_clk, \
+ .dev_id = _devname, \
+ .con_id = _conname, \
+ }