diff options
Diffstat (limited to 'drivers/clk/sunxi/clk-sunxi.c')
| -rw-r--r-- | drivers/clk/sunxi/clk-sunxi.c | 450 | 
1 files changed, 450 insertions, 0 deletions
| 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); +} |