diff options
Diffstat (limited to 'drivers/clk/sunxi')
| -rw-r--r-- | drivers/clk/sunxi/Makefile | 5 | ||||
| -rw-r--r-- | drivers/clk/sunxi/clk-factors.c | 180 | ||||
| -rw-r--r-- | drivers/clk/sunxi/clk-factors.h | 27 | ||||
| -rw-r--r-- | drivers/clk/sunxi/clk-sunxi.c | 450 | 
4 files changed, 662 insertions, 0 deletions
diff --git a/drivers/clk/sunxi/Makefile b/drivers/clk/sunxi/Makefile new file mode 100644 index 00000000000..b5bac917612 --- /dev/null +++ b/drivers/clk/sunxi/Makefile @@ -0,0 +1,5 @@ +# +# Makefile for sunxi specific clk +# + +obj-y += clk-sunxi.o clk-factors.o diff --git a/drivers/clk/sunxi/clk-factors.c b/drivers/clk/sunxi/clk-factors.c new file mode 100644 index 00000000000..88523f91d9b --- /dev/null +++ b/drivers/clk/sunxi/clk-factors.c @@ -0,0 +1,180 @@ +/* + * Copyright (C) 2013 Emilio López <emilio@elopez.com.ar> + * + * 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. + * + * Adjustable factor-based clock implementation + */ + +#include <linux/clk-provider.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/io.h> +#include <linux/err.h> +#include <linux/string.h> + +#include <linux/delay.h> + +#include "clk-factors.h" + +/* + * DOC: basic adjustable factor-based clock that cannot gate + * + * Traits of this clock: + * prepare - clk_prepare only ensures that parents are prepared + * enable - clk_enable only ensures that parents are enabled + * rate - rate is adjustable. + *        clk->rate = (parent->rate * N * (K + 1) >> P) / (M + 1) + * parent - fixed parent.  No clk_set_parent support + */ + +struct clk_factors { +	struct clk_hw hw; +	void __iomem *reg; +	struct clk_factors_config *config; +	void (*get_factors) (u32 *rate, u32 parent, u8 *n, u8 *k, u8 *m, u8 *p); +	spinlock_t *lock; +}; + +#define to_clk_factors(_hw) container_of(_hw, struct clk_factors, hw) + +#define SETMASK(len, pos)		(((-1U) >> (31-len))  << (pos)) +#define CLRMASK(len, pos)		(~(SETMASK(len, pos))) +#define FACTOR_GET(bit, len, reg)	(((reg) & SETMASK(len, bit)) >> (bit)) + +#define FACTOR_SET(bit, len, reg, val) \ +	(((reg) & CLRMASK(len, bit)) | (val << (bit))) + +static unsigned long clk_factors_recalc_rate(struct clk_hw *hw, +					     unsigned long parent_rate) +{ +	u8 n = 1, k = 0, p = 0, m = 0; +	u32 reg; +	unsigned long rate; +	struct clk_factors *factors = to_clk_factors(hw); +	struct clk_factors_config *config = factors->config; + +	/* Fetch the register value */ +	reg = readl(factors->reg); + +	/* Get each individual factor if applicable */ +	if (config->nwidth != SUNXI_FACTORS_NOT_APPLICABLE) +		n = FACTOR_GET(config->nshift, config->nwidth, reg); +	if (config->kwidth != SUNXI_FACTORS_NOT_APPLICABLE) +		k = FACTOR_GET(config->kshift, config->kwidth, reg); +	if (config->mwidth != SUNXI_FACTORS_NOT_APPLICABLE) +		m = FACTOR_GET(config->mshift, config->mwidth, reg); +	if (config->pwidth != SUNXI_FACTORS_NOT_APPLICABLE) +		p = FACTOR_GET(config->pshift, config->pwidth, reg); + +	/* Calculate the rate */ +	rate = (parent_rate * n * (k + 1) >> p) / (m + 1); + +	return rate; +} + +static long clk_factors_round_rate(struct clk_hw *hw, unsigned long rate, +				   unsigned long *parent_rate) +{ +	struct clk_factors *factors = to_clk_factors(hw); +	factors->get_factors((u32 *)&rate, (u32)*parent_rate, +			     NULL, NULL, NULL, NULL); + +	return rate; +} + +static int clk_factors_set_rate(struct clk_hw *hw, unsigned long rate, +				unsigned long parent_rate) +{ +	u8 n, k, m, p; +	u32 reg; +	struct clk_factors *factors = to_clk_factors(hw); +	struct clk_factors_config *config = factors->config; +	unsigned long flags = 0; + +	factors->get_factors((u32 *)&rate, (u32)parent_rate, &n, &k, &m, &p); + +	if (factors->lock) +		spin_lock_irqsave(factors->lock, flags); + +	/* Fetch the register value */ +	reg = readl(factors->reg); + +	/* Set up the new factors - macros do not do anything if width is 0 */ +	reg = FACTOR_SET(config->nshift, config->nwidth, reg, n); +	reg = FACTOR_SET(config->kshift, config->kwidth, reg, k); +	reg = FACTOR_SET(config->mshift, config->mwidth, reg, m); +	reg = FACTOR_SET(config->pshift, config->pwidth, reg, p); + +	/* Apply them now */ +	writel(reg, factors->reg); + +	/* delay 500us so pll stabilizes */ +	__delay((rate >> 20) * 500 / 2); + +	if (factors->lock) +		spin_unlock_irqrestore(factors->lock, flags); + +	return 0; +} + +static const struct clk_ops clk_factors_ops = { +	.recalc_rate = clk_factors_recalc_rate, +	.round_rate = clk_factors_round_rate, +	.set_rate = clk_factors_set_rate, +}; + +/** + * clk_register_factors - register a factors clock with + * the clock framework + * @dev: device registering this clock + * @name: name of this clock + * @parent_name: name of clock's parent + * @flags: framework-specific flags + * @reg: register address to adjust factors + * @config: shift and width of factors n, k, m and p + * @get_factors: function to calculate the factors for a given frequency + * @lock: shared register lock for this clock + */ +struct clk *clk_register_factors(struct device *dev, const char *name, +				 const char *parent_name, +				 unsigned long flags, void __iomem *reg, +				 struct clk_factors_config *config, +				 void (*get_factors)(u32 *rate, u32 parent, +						     u8 *n, u8 *k, u8 *m, u8 *p), +				 spinlock_t *lock) +{ +	struct clk_factors *factors; +	struct clk *clk; +	struct clk_init_data init; + +	/* allocate the factors */ +	factors = kzalloc(sizeof(struct clk_factors), GFP_KERNEL); +	if (!factors) { +		pr_err("%s: could not allocate factors clk\n", __func__); +		return ERR_PTR(-ENOMEM); +	} + +	init.name = name; +	init.ops = &clk_factors_ops; +	init.flags = flags; +	init.parent_names = (parent_name ? &parent_name : NULL); +	init.num_parents = (parent_name ? 1 : 0); + +	/* struct clk_factors assignments */ +	factors->reg = reg; +	factors->config = config; +	factors->lock = lock; +	factors->hw.init = &init; +	factors->get_factors = get_factors; + +	/* register the clock */ +	clk = clk_register(dev, &factors->hw); + +	if (IS_ERR(clk)) +		kfree(factors); + +	return clk; +} diff --git a/drivers/clk/sunxi/clk-factors.h b/drivers/clk/sunxi/clk-factors.h new file mode 100644 index 00000000000..f49851cc438 --- /dev/null +++ b/drivers/clk/sunxi/clk-factors.h @@ -0,0 +1,27 @@ +#ifndef __MACH_SUNXI_CLK_FACTORS_H +#define __MACH_SUNXI_CLK_FACTORS_H + +#include <linux/clk-provider.h> +#include <linux/clkdev.h> + +#define SUNXI_FACTORS_NOT_APPLICABLE	(0) + +struct clk_factors_config { +	u8 nshift; +	u8 nwidth; +	u8 kshift; +	u8 kwidth; +	u8 mshift; +	u8 mwidth; +	u8 pshift; +	u8 pwidth; +}; + +struct clk *clk_register_factors(struct device *dev, const char *name, +				 const char *parent_name, +				 unsigned long flags, void __iomem *reg, +				 struct clk_factors_config *config, +				 void (*get_factors) (u32 *rate, u32 parent_rate, +						      u8 *n, u8 *k, u8 *m, u8 *p), +				 spinlock_t *lock); +#endif diff --git a/drivers/clk/sunxi/clk-sunxi.c b/drivers/clk/sunxi/clk-sunxi.c new file mode 100644 index 00000000000..0bb0eb4ed21 --- /dev/null +++ b/drivers/clk/sunxi/clk-sunxi.c @@ -0,0 +1,450 @@ +/* + * Copyright 2013 Emilio López + * + * Emilio López <emilio@elopez.com.ar> + * + * 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. + */ + +#include <linux/clk-provider.h> +#include <linux/clkdev.h> +#include <linux/clk/sunxi.h> +#include <linux/of.h> +#include <linux/of_address.h> + +#include "clk-factors.h" + +static DEFINE_SPINLOCK(clk_lock); + +/** + * sunxi_osc_clk_setup() - Setup function for gatable oscillator + */ + +#define SUNXI_OSC24M_GATE	0 + +static void __init sunxi_osc_clk_setup(struct device_node *node) +{ +	struct clk *clk; +	const char *clk_name = node->name; +	const char *parent; +	void *reg; + +	reg = of_iomap(node, 0); + +	parent = of_clk_get_parent_name(node, 0); + +	clk = clk_register_gate(NULL, clk_name, parent, 0, reg, +				SUNXI_OSC24M_GATE, 0, &clk_lock); + +	if (clk) { +		of_clk_add_provider(node, of_clk_src_simple_get, clk); +		clk_register_clkdev(clk, clk_name, NULL); +	} +} + + + +/** + * sunxi_get_pll1_factors() - calculates n, k, m, p factors for PLL1 + * PLL1 rate is calculated as follows + * rate = (parent_rate * n * (k + 1) >> p) / (m + 1); + * parent_rate is always 24Mhz + */ + +static void sunxi_get_pll1_factors(u32 *freq, u32 parent_rate, +				   u8 *n, u8 *k, u8 *m, u8 *p) +{ +	u8 div; + +	/* Normalize value to a 6M multiple */ +	div = *freq / 6000000; +	*freq = 6000000 * div; + +	/* we were called to round the frequency, we can now return */ +	if (n == NULL) +		return; + +	/* m is always zero for pll1 */ +	*m = 0; + +	/* k is 1 only on these cases */ +	if (*freq >= 768000000 || *freq == 42000000 || *freq == 54000000) +		*k = 1; +	else +		*k = 0; + +	/* p will be 3 for divs under 10 */ +	if (div < 10) +		*p = 3; + +	/* p will be 2 for divs between 10 - 20 and odd divs under 32 */ +	else if (div < 20 || (div < 32 && (div & 1))) +		*p = 2; + +	/* p will be 1 for even divs under 32, divs under 40 and odd pairs +	 * of divs between 40-62 */ +	else if (div < 40 || (div < 64 && (div & 2))) +		*p = 1; + +	/* any other entries have p = 0 */ +	else +		*p = 0; + +	/* calculate a suitable n based on k and p */ +	div <<= *p; +	div /= (*k + 1); +	*n = div / 4; +} + + + +/** + * sunxi_get_apb1_factors() - calculates m, p factors for APB1 + * APB1 rate is calculated as follows + * rate = (parent_rate >> p) / (m + 1); + */ + +static void sunxi_get_apb1_factors(u32 *freq, u32 parent_rate, +				   u8 *n, u8 *k, u8 *m, u8 *p) +{ +	u8 calcm, calcp; + +	if (parent_rate < *freq) +		*freq = parent_rate; + +	parent_rate = (parent_rate + (*freq - 1)) / *freq; + +	/* Invalid rate! */ +	if (parent_rate > 32) +		return; + +	if (parent_rate <= 4) +		calcp = 0; +	else if (parent_rate <= 8) +		calcp = 1; +	else if (parent_rate <= 16) +		calcp = 2; +	else +		calcp = 3; + +	calcm = (parent_rate >> calcp) - 1; + +	*freq = (parent_rate >> calcp) / (calcm + 1); + +	/* we were called to round the frequency, we can now return */ +	if (n == NULL) +		return; + +	*m = calcm; +	*p = calcp; +} + + + +/** + * sunxi_factors_clk_setup() - Setup function for factor clocks + */ + +struct factors_data { +	struct clk_factors_config *table; +	void (*getter) (u32 *rate, u32 parent_rate, u8 *n, u8 *k, u8 *m, u8 *p); +}; + +static struct clk_factors_config pll1_config = { +	.nshift = 8, +	.nwidth = 5, +	.kshift = 4, +	.kwidth = 2, +	.mshift = 0, +	.mwidth = 2, +	.pshift = 16, +	.pwidth = 2, +}; + +static struct clk_factors_config apb1_config = { +	.mshift = 0, +	.mwidth = 5, +	.pshift = 16, +	.pwidth = 2, +}; + +static const __initconst struct factors_data pll1_data = { +	.table = &pll1_config, +	.getter = sunxi_get_pll1_factors, +}; + +static const __initconst struct factors_data apb1_data = { +	.table = &apb1_config, +	.getter = sunxi_get_apb1_factors, +}; + +static void __init sunxi_factors_clk_setup(struct device_node *node, +					   struct factors_data *data) +{ +	struct clk *clk; +	const char *clk_name = node->name; +	const char *parent; +	void *reg; + +	reg = of_iomap(node, 0); + +	parent = of_clk_get_parent_name(node, 0); + +	clk = clk_register_factors(NULL, clk_name, parent, 0, reg, +				   data->table, data->getter, &clk_lock); + +	if (clk) { +		of_clk_add_provider(node, of_clk_src_simple_get, clk); +		clk_register_clkdev(clk, clk_name, NULL); +	} +} + + + +/** + * sunxi_mux_clk_setup() - Setup function for muxes + */ + +#define SUNXI_MUX_GATE_WIDTH	2 + +struct mux_data { +	u8 shift; +}; + +static const __initconst struct mux_data cpu_data = { +	.shift = 16, +}; + +static const __initconst struct mux_data apb1_mux_data = { +	.shift = 24, +}; + +static void __init sunxi_mux_clk_setup(struct device_node *node, +				       struct mux_data *data) +{ +	struct clk *clk; +	const char *clk_name = node->name; +	const char *parents[5]; +	void *reg; +	int i = 0; + +	reg = of_iomap(node, 0); + +	while (i < 5 && (parents[i] = of_clk_get_parent_name(node, i)) != NULL) +		i++; + +	clk = clk_register_mux(NULL, clk_name, parents, i, 0, reg, +			       data->shift, SUNXI_MUX_GATE_WIDTH, +			       0, &clk_lock); + +	if (clk) { +		of_clk_add_provider(node, of_clk_src_simple_get, clk); +		clk_register_clkdev(clk, clk_name, NULL); +	} +} + + + +/** + * sunxi_divider_clk_setup() - Setup function for simple divider clocks + */ + +#define SUNXI_DIVISOR_WIDTH	2 + +struct div_data { +	u8 shift; +	u8 pow; +}; + +static const __initconst struct div_data axi_data = { +	.shift = 0, +	.pow = 0, +}; + +static const __initconst struct div_data ahb_data = { +	.shift = 4, +	.pow = 1, +}; + +static const __initconst struct div_data apb0_data = { +	.shift = 8, +	.pow = 1, +}; + +static void __init sunxi_divider_clk_setup(struct device_node *node, +					   struct div_data *data) +{ +	struct clk *clk; +	const char *clk_name = node->name; +	const char *clk_parent; +	void *reg; + +	reg = of_iomap(node, 0); + +	clk_parent = of_clk_get_parent_name(node, 0); + +	clk = clk_register_divider(NULL, clk_name, clk_parent, 0, +				   reg, data->shift, SUNXI_DIVISOR_WIDTH, +				   data->pow ? CLK_DIVIDER_POWER_OF_TWO : 0, +				   &clk_lock); +	if (clk) { +		of_clk_add_provider(node, of_clk_src_simple_get, clk); +		clk_register_clkdev(clk, clk_name, NULL); +	} +} + + + +/** + * sunxi_gates_clk_setup() - Setup function for leaf gates on clocks + */ + +#define SUNXI_GATES_MAX_SIZE	64 + +struct gates_data { +	DECLARE_BITMAP(mask, SUNXI_GATES_MAX_SIZE); +}; + +static const __initconst struct gates_data axi_gates_data = { +	.mask = {1}, +}; + +static const __initconst struct gates_data ahb_gates_data = { +	.mask = {0x7F77FFF, 0x14FB3F}, +}; + +static const __initconst struct gates_data apb0_gates_data = { +	.mask = {0x4EF}, +}; + +static const __initconst struct gates_data apb1_gates_data = { +	.mask = {0xFF00F7}, +}; + +static void __init sunxi_gates_clk_setup(struct device_node *node, +					 struct gates_data *data) +{ +	struct clk_onecell_data *clk_data; +	const char *clk_parent; +	const char *clk_name; +	void *reg; +	int qty; +	int i = 0; +	int j = 0; +	int ignore; + +	reg = of_iomap(node, 0); + +	clk_parent = of_clk_get_parent_name(node, 0); + +	/* Worst-case size approximation and memory allocation */ +	qty = find_last_bit(data->mask, SUNXI_GATES_MAX_SIZE); +	clk_data = kmalloc(sizeof(struct clk_onecell_data), GFP_KERNEL); +	if (!clk_data) +		return; +	clk_data->clks = kzalloc((qty+1) * sizeof(struct clk *), GFP_KERNEL); +	if (!clk_data->clks) { +		kfree(clk_data); +		return; +	} + +	for_each_set_bit(i, data->mask, SUNXI_GATES_MAX_SIZE) { +		of_property_read_string_index(node, "clock-output-names", +					      j, &clk_name); + +		/* No driver claims this clock, but it should remain gated */ +		ignore = !strcmp("ahb_sdram", clk_name) ? CLK_IGNORE_UNUSED : 0; + +		clk_data->clks[i] = clk_register_gate(NULL, clk_name, +						      clk_parent, ignore, +						      reg + 4 * (i/32), i % 32, +						      0, &clk_lock); +		WARN_ON(IS_ERR(clk_data->clks[i])); + +		j++; +	} + +	/* Adjust to the real max */ +	clk_data->clk_num = i; + +	of_clk_add_provider(node, of_clk_src_onecell_get, clk_data); +} + +/* Matches for of_clk_init */ +static const __initconst struct of_device_id clk_match[] = { +	{.compatible = "fixed-clock", .data = of_fixed_clk_setup,}, +	{.compatible = "allwinner,sun4i-osc-clk", .data = sunxi_osc_clk_setup,}, +	{} +}; + +/* Matches for factors clocks */ +static const __initconst struct of_device_id clk_factors_match[] = { +	{.compatible = "allwinner,sun4i-pll1-clk", .data = &pll1_data,}, +	{.compatible = "allwinner,sun4i-apb1-clk", .data = &apb1_data,}, +	{} +}; + +/* Matches for divider clocks */ +static const __initconst struct of_device_id clk_div_match[] = { +	{.compatible = "allwinner,sun4i-axi-clk", .data = &axi_data,}, +	{.compatible = "allwinner,sun4i-ahb-clk", .data = &ahb_data,}, +	{.compatible = "allwinner,sun4i-apb0-clk", .data = &apb0_data,}, +	{} +}; + +/* Matches for mux clocks */ +static const __initconst struct of_device_id clk_mux_match[] = { +	{.compatible = "allwinner,sun4i-cpu-clk", .data = &cpu_data,}, +	{.compatible = "allwinner,sun4i-apb1-mux-clk", .data = &apb1_mux_data,}, +	{} +}; + +/* Matches for gate clocks */ +static const __initconst struct of_device_id clk_gates_match[] = { +	{.compatible = "allwinner,sun4i-axi-gates-clk", .data = &axi_gates_data,}, +	{.compatible = "allwinner,sun4i-ahb-gates-clk", .data = &ahb_gates_data,}, +	{.compatible = "allwinner,sun4i-apb0-gates-clk", .data = &apb0_gates_data,}, +	{.compatible = "allwinner,sun4i-apb1-gates-clk", .data = &apb1_gates_data,}, +	{} +}; + +static void __init of_sunxi_table_clock_setup(const struct of_device_id *clk_match, +					      void *function) +{ +	struct device_node *np; +	const struct div_data *data; +	const struct of_device_id *match; +	void (*setup_function)(struct device_node *, const void *) = function; + +	for_each_matching_node(np, clk_match) { +		match = of_match_node(clk_match, np); +		data = match->data; +		setup_function(np, data); +	} +} + +void __init sunxi_init_clocks(void) +{ +	/* Register all the simple sunxi clocks on DT */ +	of_clk_init(clk_match); + +	/* Register factor clocks */ +	of_sunxi_table_clock_setup(clk_factors_match, sunxi_factors_clk_setup); + +	/* Register divider clocks */ +	of_sunxi_table_clock_setup(clk_div_match, sunxi_divider_clk_setup); + +	/* Register mux clocks */ +	of_sunxi_table_clock_setup(clk_mux_match, sunxi_mux_clk_setup); + +	/* Register gate clocks */ +	of_sunxi_table_clock_setup(clk_gates_match, sunxi_gates_clk_setup); +}  |