/* * 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__ */