| /* |
| * 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/clkdev.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: %s\n", |
| node->name); |
| 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; |
| struct clk *gt; |
| |
| 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: %s\n", |
| node->name); |
| return; |
| } |
| |
| gt = sunxi_factors_register(node, &sun9i_a80_gt_data, |
| &sun9i_a80_gt_lock, reg); |
| |
| /* The GT bus clock needs to be always enabled */ |
| __clk_get(gt); |
| clk_prepare_enable(gt); |
| } |
| 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: %s\n", |
| node->name); |
| 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: %s\n", |
| node->name); |
| 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: %s\n", |
| node->name); |
| 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); |