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| -rw-r--r-- | drivers/clk/ingenic/cgu.h | 233 |
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diff --git a/drivers/clk/ingenic/cgu.h b/drivers/clk/ingenic/cgu.h new file mode 100644 index 000000000..e12716d8c --- /dev/null +++ b/drivers/clk/ingenic/cgu.h @@ -0,0 +1,233 @@ +/* + * Ingenic SoC CGU driver + * + * Copyright (c) 2013-2015 Imagination Technologies + * Author: Paul Burton <paul.burton@mips.com> + * + * 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. + */ + +#ifndef __DRIVERS_CLK_INGENIC_CGU_H__ +#define __DRIVERS_CLK_INGENIC_CGU_H__ + +#include <linux/bitops.h> +#include <linux/of.h> +#include <linux/spinlock.h> + +/** + * struct ingenic_cgu_pll_info - information about a PLL + * @reg: the offset of the PLL's control register within the CGU + * @m_shift: the number of bits to shift the multiplier value by (ie. the + * index of the lowest bit of the multiplier value in the PLL's + * control register) + * @m_bits: the size of the multiplier field in bits + * @m_offset: the multiplier value which encodes to 0 in the PLL's control + * register + * @n_shift: the number of bits to shift the divider value by (ie. the + * index of the lowest bit of the divider value in the PLL's + * control register) + * @n_bits: the size of the divider field in bits + * @n_offset: the divider value which encodes to 0 in the PLL's control + * register + * @od_shift: the number of bits to shift the post-VCO divider value by (ie. + * the index of the lowest bit of the post-VCO divider value in + * the PLL's control register) + * @od_bits: the size of the post-VCO divider field in bits + * @od_max: the maximum post-VCO divider value + * @od_encoding: a pointer to an array mapping post-VCO divider values to + * their encoded values in the PLL control register, or -1 for + * unsupported values + * @bypass_bit: the index of the bypass bit in the PLL control register + * @enable_bit: the index of the enable bit in the PLL control register + * @stable_bit: the index of the stable bit in the PLL control register + * @no_bypass_bit: if set, the PLL has no bypass functionality + */ +struct ingenic_cgu_pll_info { + unsigned reg; + const s8 *od_encoding; + u8 m_shift, m_bits, m_offset; + u8 n_shift, n_bits, n_offset; + u8 od_shift, od_bits, od_max; + u8 bypass_bit; + u8 enable_bit; + u8 stable_bit; + bool no_bypass_bit; +}; + +/** + * struct ingenic_cgu_mux_info - information about a clock mux + * @reg: offset of the mux control register within the CGU + * @shift: number of bits to shift the mux value by (ie. the index of + * the lowest bit of the mux value within its control register) + * @bits: the size of the mux value in bits + */ +struct ingenic_cgu_mux_info { + unsigned reg; + u8 shift; + u8 bits; +}; + +/** + * struct ingenic_cgu_div_info - information about a divider + * @reg: offset of the divider control register within the CGU + * @shift: number of bits to left shift the divide value by (ie. the index of + * the lowest bit of the divide value within its control register) + * @div: number to divide the divider value by (i.e. if the + * effective divider value is the value written to the register + * multiplied by some constant) + * @bits: the size of the divide value in bits + * @ce_bit: the index of the change enable bit within reg, or -1 if there + * isn't one + * @busy_bit: the index of the busy bit within reg, or -1 if there isn't one + * @stop_bit: the index of the stop bit within reg, or -1 if there isn't one + */ +struct ingenic_cgu_div_info { + unsigned reg; + u8 shift; + u8 div; + u8 bits; + s8 ce_bit; + s8 busy_bit; + s8 stop_bit; +}; + +/** + * struct ingenic_cgu_fixdiv_info - information about a fixed divider + * @div: the divider applied to the parent clock + */ +struct ingenic_cgu_fixdiv_info { + unsigned div; +}; + +/** + * struct ingenic_cgu_gate_info - information about a clock gate + * @reg: offset of the gate control register within the CGU + * @bit: offset of the bit in the register that controls the gate + * @clear_to_gate: if set, the clock is gated when the bit is cleared + * @delay_us: delay in microseconds after which the clock is considered stable + */ +struct ingenic_cgu_gate_info { + unsigned reg; + u8 bit; + bool clear_to_gate; + u16 delay_us; +}; + +/** + * struct ingenic_cgu_custom_info - information about a custom (SoC) clock + * @clk_ops: custom clock operation callbacks + */ +struct ingenic_cgu_custom_info { + const struct clk_ops *clk_ops; +}; + +/** + * struct ingenic_cgu_clk_info - information about a clock + * @name: name of the clock + * @type: a bitmask formed from CGU_CLK_* values + * @parents: an array of the indices of potential parents of this clock + * within the clock_info array of the CGU, or -1 in entries + * which correspond to no valid parent + * @pll: information valid if type includes CGU_CLK_PLL + * @gate: information valid if type includes CGU_CLK_GATE + * @mux: information valid if type includes CGU_CLK_MUX + * @div: information valid if type includes CGU_CLK_DIV + * @fixdiv: information valid if type includes CGU_CLK_FIXDIV + * @custom: information valid if type includes CGU_CLK_CUSTOM + */ +struct ingenic_cgu_clk_info { + const char *name; + + enum { + CGU_CLK_NONE = 0, + CGU_CLK_EXT = BIT(0), + CGU_CLK_PLL = BIT(1), + CGU_CLK_GATE = BIT(2), + CGU_CLK_MUX = BIT(3), + CGU_CLK_MUX_GLITCHFREE = BIT(4), + CGU_CLK_DIV = BIT(5), + CGU_CLK_FIXDIV = BIT(6), + CGU_CLK_CUSTOM = BIT(7), + } type; + + int parents[4]; + + union { + struct ingenic_cgu_pll_info pll; + + struct { + struct ingenic_cgu_gate_info gate; + struct ingenic_cgu_mux_info mux; + struct ingenic_cgu_div_info div; + struct ingenic_cgu_fixdiv_info fixdiv; + }; + + struct ingenic_cgu_custom_info custom; + }; +}; + +/** + * struct ingenic_cgu - data about the CGU + * @np: the device tree node that caused the CGU to be probed + * @base: the ioremap'ed base address of the CGU registers + * @clock_info: an array containing information about implemented clocks + * @clocks: used to provide clocks to DT, allows lookup of struct clk* + * @lock: lock to be held whilst manipulating CGU registers + */ +struct ingenic_cgu { + struct device_node *np; + void __iomem *base; + + const struct ingenic_cgu_clk_info *clock_info; + struct clk_onecell_data clocks; + + spinlock_t lock; +}; + +/** + * struct ingenic_clk - private data for a clock + * @hw: see Documentation/driver-api/clk.rst + * @cgu: a pointer to the CGU data + * @idx: the index of this clock in cgu->clock_info + */ +struct ingenic_clk { + struct clk_hw hw; + struct ingenic_cgu *cgu; + unsigned idx; +}; + +#define to_ingenic_clk(_hw) container_of(_hw, struct ingenic_clk, hw) + +/** + * ingenic_cgu_new() - create a new CGU instance + * @clock_info: an array of clock information structures describing the clocks + * which are implemented by the CGU + * @num_clocks: the number of entries in clock_info + * @np: the device tree node which causes this CGU to be probed + * + * Return: a pointer to the CGU instance if initialisation is successful, + * otherwise NULL. + */ +struct ingenic_cgu * +ingenic_cgu_new(const struct ingenic_cgu_clk_info *clock_info, + unsigned num_clocks, struct device_node *np); + +/** + * ingenic_cgu_register_clocks() - Registers the clocks + * @cgu: pointer to cgu data + * + * Register the clocks described by the CGU with the common clock framework. + * + * Return: 0 on success or -errno if unsuccesful. + */ +int ingenic_cgu_register_clocks(struct ingenic_cgu *cgu); + +#endif /* __DRIVERS_CLK_INGENIC_CGU_H__ */ |