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Diffstat (limited to 'arch/arm/mach-ux500/clock.h')
| -rw-r--r-- | arch/arm/mach-ux500/clock.h | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/arch/arm/mach-ux500/clock.h b/arch/arm/mach-ux500/clock.h new file mode 100644 index 000000000000..e4f99b65026f --- /dev/null +++ b/arch/arm/mach-ux500/clock.h @@ -0,0 +1,125 @@ +/* + * 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, \ + } |