drivers/clk/sunxi/clk-sun9i-core.c - linux - Git at Google

 /*
  * Copyright 2014 Chen-Yu Tsai
  *
  * Chen-Yu Tsai <wens@csie.org>
  *
  * 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.h>
 #include <linux/clk-provider.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/log2.h>

 #include "clk-factors.h"


 /**
  * sun9i_a80_get_pll4_factors() - calculates n, p, m factors for PLL4
  * PLL4 rate is calculated as follows
  * rate = (parent_rate * n >> p) / (m + 1);
  * parent_rate is always 24MHz
  *
  * p and m are named div1 and div2 in Allwinner's SDK
  */

 static void sun9i_a80_get_pll4_factors(struct factors_request *req)
 {
 	int n;
 	int m = 1;
 	int p = 1;

 	/* Normalize value to a 6 MHz multiple (24 MHz / 4) */
 	n = DIV_ROUND_UP(req->rate, 6000000);

 	/* If n is too large switch to steps of 12 MHz */
 	if (n > 255) {
 		m = 0;
 		n = (n + 1) / 2;
 	}

 	/* If n is still too large switch to steps of 24 MHz */
 	if (n > 255) {
 		p = 0;
 		n = (n + 1) / 2;
 	}

 	/* n must be between 12 and 255 */
 	if (n > 255)
 		n = 255;
 	else if (n < 12)
 		n = 12;

 	req->rate = ((24000000 * n) >> p) / (m + 1);
 	req->n = n;
 	req->m = m;
 	req->p = p;
 }

 static const struct clk_factors_config sun9i_a80_pll4_config = {
 	.mshift = 18,
 	.mwidth = 1,
 	.nshift = 8,
 	.nwidth = 8,
 	.pshift = 16,
 	.pwidth = 1,
 };

 static const struct factors_data sun9i_a80_pll4_data __initconst = {
 	.enable = 31,
 	.table = &sun9i_a80_pll4_config,
 	.getter = sun9i_a80_get_pll4_factors,
 };

 static DEFINE_SPINLOCK(sun9i_a80_pll4_lock);

 static void __init sun9i_a80_pll4_setup(struct device_node *node)
 {
 	void __iomem *reg;

 	reg = of_io_request_and_map(node, 0, of_node_full_name(node));
 	if (IS_ERR(reg)) {
 		pr_err("Could not get registers for a80-pll4-clk: %pOFn\n",
 		       node);
 		return;
 	}

 	sunxi_factors_register(node, &sun9i_a80_pll4_data,
 			       &sun9i_a80_pll4_lock, reg);
 }
 CLK_OF_DECLARE(sun9i_a80_pll4, "allwinner,sun9i-a80-pll4-clk", sun9i_a80_pll4_setup);


 /**
  * sun9i_a80_get_gt_factors() - calculates m factor for GT
  * GT rate is calculated as follows
  * rate = parent_rate / (m + 1);
  */

 static void sun9i_a80_get_gt_factors(struct factors_request *req)
 {
 	u32 div;

 	if (req->parent_rate < req->rate)
 		req->rate = req->parent_rate;

 	div = DIV_ROUND_UP(req->parent_rate, req->rate);

 	/* maximum divider is 4 */
 	if (div > 4)
 		div = 4;

 	req->rate = req->parent_rate / div;
 	req->m = div;
 }

 static const struct clk_factors_config sun9i_a80_gt_config = {
 	.mshift = 0,
 	.mwidth = 2,
 };

 static const struct factors_data sun9i_a80_gt_data __initconst = {
 	.mux = 24,
 	.muxmask = BIT(1) | BIT(0),
 	.table = &sun9i_a80_gt_config,
 	.getter = sun9i_a80_get_gt_factors,
 };

 static DEFINE_SPINLOCK(sun9i_a80_gt_lock);

 static void __init sun9i_a80_gt_setup(struct device_node *node)
 {
 	void __iomem *reg;

 	reg = of_io_request_and_map(node, 0, of_node_full_name(node));
 	if (IS_ERR(reg)) {
 		pr_err("Could not get registers for a80-gt-clk: %pOFn\n",
 		       node);
 		return;
 	}

 	/* The GT bus clock needs to be always enabled */
 	sunxi_factors_register_critical(node, &sun9i_a80_gt_data,
 					&sun9i_a80_gt_lock, reg);
 }
 CLK_OF_DECLARE(sun9i_a80_gt, "allwinner,sun9i-a80-gt-clk", sun9i_a80_gt_setup);


 /**
  * sun9i_a80_get_ahb_factors() - calculates p factor for AHB0/1/2
  * AHB rate is calculated as follows
  * rate = parent_rate >> p;
  */

 static void sun9i_a80_get_ahb_factors(struct factors_request *req)
 {
 	u32 _p;

 	if (req->parent_rate < req->rate)
 		req->rate = req->parent_rate;

 	_p = order_base_2(DIV_ROUND_UP(req->parent_rate, req->rate));

 	/* maximum p is 3 */
 	if (_p > 3)
 		_p = 3;

 	req->rate = req->parent_rate >> _p;
 	req->p = _p;
 }

 static const struct clk_factors_config sun9i_a80_ahb_config = {
 	.pshift = 0,
 	.pwidth = 2,
 };

 static const struct factors_data sun9i_a80_ahb_data __initconst = {
 	.mux = 24,
 	.muxmask = BIT(1) | BIT(0),
 	.table = &sun9i_a80_ahb_config,
 	.getter = sun9i_a80_get_ahb_factors,
 };

 static DEFINE_SPINLOCK(sun9i_a80_ahb_lock);

 static void __init sun9i_a80_ahb_setup(struct device_node *node)
 {
 	void __iomem *reg;

 	reg = of_io_request_and_map(node, 0, of_node_full_name(node));
 	if (IS_ERR(reg)) {
 		pr_err("Could not get registers for a80-ahb-clk: %pOFn\n",
 		       node);
 		return;
 	}

 	sunxi_factors_register(node, &sun9i_a80_ahb_data,
 			       &sun9i_a80_ahb_lock, reg);
 }
 CLK_OF_DECLARE(sun9i_a80_ahb, "allwinner,sun9i-a80-ahb-clk", sun9i_a80_ahb_setup);


 static const struct factors_data sun9i_a80_apb0_data __initconst = {
 	.mux = 24,
 	.muxmask = BIT(0),
 	.table = &sun9i_a80_ahb_config,
 	.getter = sun9i_a80_get_ahb_factors,
 };

 static DEFINE_SPINLOCK(sun9i_a80_apb0_lock);

 static void __init sun9i_a80_apb0_setup(struct device_node *node)
 {
 	void __iomem *reg;

 	reg = of_io_request_and_map(node, 0, of_node_full_name(node));
 	if (IS_ERR(reg)) {
 		pr_err("Could not get registers for a80-apb0-clk: %pOFn\n",
 		       node);
 		return;
 	}

 	sunxi_factors_register(node, &sun9i_a80_apb0_data,
 			       &sun9i_a80_apb0_lock, reg);
 }
 CLK_OF_DECLARE(sun9i_a80_apb0, "allwinner,sun9i-a80-apb0-clk", sun9i_a80_apb0_setup);


 /**
  * sun9i_a80_get_apb1_factors() - calculates m, p factors for APB1
  * APB1 rate is calculated as follows
  * rate = (parent_rate >> p) / (m + 1);
  */

 static void sun9i_a80_get_apb1_factors(struct factors_request *req)
 {
 	u32 div;

 	if (req->parent_rate < req->rate)
 		req->rate = req->parent_rate;

 	div = DIV_ROUND_UP(req->parent_rate, req->rate);

 	/* Highest possible divider is 256 (p = 3, m = 31) */
 	if (div > 256)
 		div = 256;

 	req->p = order_base_2(div);
 	req->m = (req->parent_rate >> req->p) - 1;
 	req->rate = (req->parent_rate >> req->p) / (req->m + 1);
 }

 static const struct clk_factors_config sun9i_a80_apb1_config = {
 	.mshift = 0,
 	.mwidth = 5,
 	.pshift = 16,
 	.pwidth = 2,
 };

 static const struct factors_data sun9i_a80_apb1_data __initconst = {
 	.mux = 24,
 	.muxmask = BIT(0),
 	.table = &sun9i_a80_apb1_config,
 	.getter = sun9i_a80_get_apb1_factors,
 };

 static DEFINE_SPINLOCK(sun9i_a80_apb1_lock);

 static void __init sun9i_a80_apb1_setup(struct device_node *node)
 {
 	void __iomem *reg;

 	reg = of_io_request_and_map(node, 0, of_node_full_name(node));
 	if (IS_ERR(reg)) {
 		pr_err("Could not get registers for a80-apb1-clk: %pOFn\n",
 		       node);
 		return;
 	}

 	sunxi_factors_register(node, &sun9i_a80_apb1_data,
 			       &sun9i_a80_apb1_lock, reg);
 }
 CLK_OF_DECLARE(sun9i_a80_apb1, "allwinner,sun9i-a80-apb1-clk", sun9i_a80_apb1_setup);
	/*
	* Copyright 2014 Chen-Yu Tsai
	*
	* Chen-Yu Tsai <wens@csie.org>
	*
	* 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.h>
	#include <linux/clk-provider.h>
	#include <linux/of.h>
	#include <linux/of_address.h>
	#include <linux/log2.h>

	#include "clk-factors.h"


	/**
	* sun9i_a80_get_pll4_factors() - calculates n, p, m factors for PLL4
	* PLL4 rate is calculated as follows
	* rate = (parent_rate * n >> p) / (m + 1);
	* parent_rate is always 24MHz
	*
	* p and m are named div1 and div2 in Allwinner's SDK
	*/

	static void sun9i_a80_get_pll4_factors(struct factors_request *req)
	{
	int n;
	int m = 1;
	int p = 1;

	/* Normalize value to a 6 MHz multiple (24 MHz / 4) */
	n = DIV_ROUND_UP(req->rate, 6000000);

	/* If n is too large switch to steps of 12 MHz */
	if (n > 255) {
	m = 0;
	n = (n + 1) / 2;
	}

	/* If n is still too large switch to steps of 24 MHz */
	if (n > 255) {
	p = 0;
	n = (n + 1) / 2;
	}

	/* n must be between 12 and 255 */
	if (n > 255)
	n = 255;
	else if (n < 12)
	n = 12;

	req->rate = ((24000000 * n) >> p) / (m + 1);
	req->n = n;
	req->m = m;
	req->p = p;
	}

	static const struct clk_factors_config sun9i_a80_pll4_config = {
	.mshift = 18,
	.mwidth = 1,
	.nshift = 8,
	.nwidth = 8,
	.pshift = 16,
	.pwidth = 1,
	};

	static const struct factors_data sun9i_a80_pll4_data __initconst = {
	.enable = 31,
	.table = &sun9i_a80_pll4_config,
	.getter = sun9i_a80_get_pll4_factors,
	};

	static DEFINE_SPINLOCK(sun9i_a80_pll4_lock);

	static void __init sun9i_a80_pll4_setup(struct device_node *node)
	{
	void __iomem *reg;

	reg = of_io_request_and_map(node, 0, of_node_full_name(node));
	if (IS_ERR(reg)) {
	pr_err("Could not get registers for a80-pll4-clk: %pOFn\n",
	node);
	return;
	}

	sunxi_factors_register(node, &sun9i_a80_pll4_data,
	&sun9i_a80_pll4_lock, reg);
	}
	CLK_OF_DECLARE(sun9i_a80_pll4, "allwinner,sun9i-a80-pll4-clk", sun9i_a80_pll4_setup);


	/**
	* sun9i_a80_get_gt_factors() - calculates m factor for GT
	* GT rate is calculated as follows
	* rate = parent_rate / (m + 1);
	*/

	static void sun9i_a80_get_gt_factors(struct factors_request *req)
	{
	u32 div;

	if (req->parent_rate < req->rate)
	req->rate = req->parent_rate;

	div = DIV_ROUND_UP(req->parent_rate, req->rate);

	/* maximum divider is 4 */
	if (div > 4)
	div = 4;

	req->rate = req->parent_rate / div;
	req->m = div;
	}

	static const struct clk_factors_config sun9i_a80_gt_config = {
	.mshift = 0,
	.mwidth = 2,
	};

	static const struct factors_data sun9i_a80_gt_data __initconst = {
	.mux = 24,
	.muxmask = BIT(1) \| BIT(0),
	.table = &sun9i_a80_gt_config,
	.getter = sun9i_a80_get_gt_factors,
	};

	static DEFINE_SPINLOCK(sun9i_a80_gt_lock);

	static void __init sun9i_a80_gt_setup(struct device_node *node)
	{
	void __iomem *reg;

	reg = of_io_request_and_map(node, 0, of_node_full_name(node));
	if (IS_ERR(reg)) {
	pr_err("Could not get registers for a80-gt-clk: %pOFn\n",
	node);
	return;
	}

	/* The GT bus clock needs to be always enabled */
	sunxi_factors_register_critical(node, &sun9i_a80_gt_data,
	&sun9i_a80_gt_lock, reg);
	}
	CLK_OF_DECLARE(sun9i_a80_gt, "allwinner,sun9i-a80-gt-clk", sun9i_a80_gt_setup);


	/**
	* sun9i_a80_get_ahb_factors() - calculates p factor for AHB0/1/2
	* AHB rate is calculated as follows
	* rate = parent_rate >> p;
	*/

	static void sun9i_a80_get_ahb_factors(struct factors_request *req)
	{
	u32 _p;

	if (req->parent_rate < req->rate)
	req->rate = req->parent_rate;

	_p = order_base_2(DIV_ROUND_UP(req->parent_rate, req->rate));

	/* maximum p is 3 */
	if (_p > 3)
	_p = 3;

	req->rate = req->parent_rate >> _p;
	req->p = _p;
	}

	static const struct clk_factors_config sun9i_a80_ahb_config = {
	.pshift = 0,
	.pwidth = 2,
	};

	static const struct factors_data sun9i_a80_ahb_data __initconst = {
	.mux = 24,
	.muxmask = BIT(1) \| BIT(0),
	.table = &sun9i_a80_ahb_config,
	.getter = sun9i_a80_get_ahb_factors,
	};

	static DEFINE_SPINLOCK(sun9i_a80_ahb_lock);

	static void __init sun9i_a80_ahb_setup(struct device_node *node)
	{
	void __iomem *reg;

	reg = of_io_request_and_map(node, 0, of_node_full_name(node));
	if (IS_ERR(reg)) {
	pr_err("Could not get registers for a80-ahb-clk: %pOFn\n",
	node);
	return;
	}

	sunxi_factors_register(node, &sun9i_a80_ahb_data,
	&sun9i_a80_ahb_lock, reg);
	}
	CLK_OF_DECLARE(sun9i_a80_ahb, "allwinner,sun9i-a80-ahb-clk", sun9i_a80_ahb_setup);


	static const struct factors_data sun9i_a80_apb0_data __initconst = {
	.mux = 24,
	.muxmask = BIT(0),
	.table = &sun9i_a80_ahb_config,
	.getter = sun9i_a80_get_ahb_factors,
	};

	static DEFINE_SPINLOCK(sun9i_a80_apb0_lock);

	static void __init sun9i_a80_apb0_setup(struct device_node *node)
	{
	void __iomem *reg;

	reg = of_io_request_and_map(node, 0, of_node_full_name(node));
	if (IS_ERR(reg)) {
	pr_err("Could not get registers for a80-apb0-clk: %pOFn\n",
	node);
	return;
	}

	sunxi_factors_register(node, &sun9i_a80_apb0_data,
	&sun9i_a80_apb0_lock, reg);
	}
	CLK_OF_DECLARE(sun9i_a80_apb0, "allwinner,sun9i-a80-apb0-clk", sun9i_a80_apb0_setup);


	/**
	* sun9i_a80_get_apb1_factors() - calculates m, p factors for APB1
	* APB1 rate is calculated as follows
	* rate = (parent_rate >> p) / (m + 1);
	*/

	static void sun9i_a80_get_apb1_factors(struct factors_request *req)
	{
	u32 div;

	if (req->parent_rate < req->rate)
	req->rate = req->parent_rate;

	div = DIV_ROUND_UP(req->parent_rate, req->rate);

	/* Highest possible divider is 256 (p = 3, m = 31) */
	if (div > 256)
	div = 256;

	req->p = order_base_2(div);
	req->m = (req->parent_rate >> req->p) - 1;
	req->rate = (req->parent_rate >> req->p) / (req->m + 1);
	}

	static const struct clk_factors_config sun9i_a80_apb1_config = {
	.mshift = 0,
	.mwidth = 5,
	.pshift = 16,
	.pwidth = 2,
	};

	static const struct factors_data sun9i_a80_apb1_data __initconst = {
	.mux = 24,
	.muxmask = BIT(0),
	.table = &sun9i_a80_apb1_config,
	.getter = sun9i_a80_get_apb1_factors,
	};

	static DEFINE_SPINLOCK(sun9i_a80_apb1_lock);

	static void __init sun9i_a80_apb1_setup(struct device_node *node)
	{
	void __iomem *reg;

	reg = of_io_request_and_map(node, 0, of_node_full_name(node));
	if (IS_ERR(reg)) {
	pr_err("Could not get registers for a80-apb1-clk: %pOFn\n",
	node);
	return;
	}

	sunxi_factors_register(node, &sun9i_a80_apb1_data,
	&sun9i_a80_apb1_lock, reg);
	}
	CLK_OF_DECLARE(sun9i_a80_apb1, "allwinner,sun9i-a80-apb1-clk", sun9i_a80_apb1_setup);