From f2e0a53271a439a2ab142645867f0cde45b2b3cd Mon Sep 17 00:00:00 2001 From: Maxime Ripard Date: Tue, 19 May 2015 22:19:33 +0200 Subject: clk: Add a basic multiplier clock Some clocks are using a multiplier component, however, unlike their mux, gate or divider counterpart, these factors don't have a basic clock implementation. This leads to code duplication across platforms that want to use that kind of clocks, and the impossibility to use the composite clocks with such a clock without defining your own rate operations. Create such a driver in order to remove these issues, and hopefully factor the implementations, reducing code size across platforms and consolidating the various implementations. Signed-off-by: Maxime Ripard Reviewed-by: Chen-Yu Tsai --- include/linux/clk-provider.h | 42 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) (limited to 'include') diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h index 3ecc07d0da77..6a7dfe33a317 100644 --- a/include/linux/clk-provider.h +++ b/include/linux/clk-provider.h @@ -518,6 +518,48 @@ struct clk *clk_register_fractional_divider(struct device *dev, void __iomem *reg, u8 mshift, u8 mwidth, u8 nshift, u8 nwidth, u8 clk_divider_flags, spinlock_t *lock); +/** + * struct clk_multiplier - adjustable multiplier clock + * + * @hw: handle between common and hardware-specific interfaces + * @reg: register containing the multiplier + * @shift: shift to the multiplier bit field + * @width: width of the multiplier bit field + * @lock: register lock + * + * Clock with an adjustable multiplier affecting its output frequency. + * Implements .recalc_rate, .set_rate and .round_rate + * + * Flags: + * CLK_MULTIPLIER_ZERO_BYPASS - By default, the multiplier is the value read + * from the register, with 0 being a valid value effectively + * zeroing the output clock rate. If CLK_MULTIPLIER_ZERO_BYPASS is + * set, then a null multiplier will be considered as a bypass, + * leaving the parent rate unmodified. + * CLK_MULTIPLIER_ROUND_CLOSEST - Makes the best calculated divider to be + * rounded to the closest integer instead of the down one. + */ +struct clk_multiplier { + struct clk_hw hw; + void __iomem *reg; + u8 shift; + u8 width; + u8 flags; + spinlock_t *lock; +}; + +#define CLK_MULTIPLIER_ZERO_BYPASS BIT(0) +#define CLK_MULTIPLIER_ROUND_CLOSEST BIT(1) + +extern const struct clk_ops clk_multiplier_ops; + +struct clk *clk_register_multiplier(struct device *dev, const char *name, + const char *parent_name, + unsigned long flags, + void __iomem *reg, u8 shift, u8 width, + u8 clk_mult_flags, spinlock_t *lock); +void clk_unregister_multiplier(struct clk *clk); + /*** * struct clk_composite - aggregate clock of mux, divider and gate clocks * -- cgit v1.2.3 From 460d0d444822e9032a2573fc051b45c68b89a97a Mon Sep 17 00:00:00 2001 From: Maxime Ripard Date: Fri, 18 Jul 2014 15:48:35 -0300 Subject: clk: sunxi: Add a driver for the PLL2 The PLL2 on the A10 and later SoCs is the clock used for all the audio related operations. This clock has a somewhat complex output tree, with three outputs (2X, 4X and 8X) with a fixed divider from the base clock, and an output (1X) with a post divider. However, we can simplify things since the 1X divider can be fixed, and we end up by having a base clock not exposed to any device (or at least directly, since the 4X output doesn't have any divider), and 4 fixed divider clocks that will be exposed. This clock seems to have been introduced, at least in this form, in the revision B of the A10, but we don't have any information on the clock used on the revision A. Signed-off-by: Maxime Ripard Reviewed-by: Chen-Yu Tsai --- drivers/clk/sunxi/Makefile | 1 + drivers/clk/sunxi/clk-a10-pll2.c | 188 +++++++++++++++++++++++++++++ include/dt-bindings/clock/sun4i-a10-pll2.h | 53 ++++++++ 3 files changed, 242 insertions(+) create mode 100644 drivers/clk/sunxi/clk-a10-pll2.c create mode 100644 include/dt-bindings/clock/sun4i-a10-pll2.h (limited to 'include') diff --git a/drivers/clk/sunxi/Makefile b/drivers/clk/sunxi/Makefile index f5a35b82cc1a..c658a18ba7cb 100644 --- a/drivers/clk/sunxi/Makefile +++ b/drivers/clk/sunxi/Makefile @@ -4,6 +4,7 @@ obj-y += clk-sunxi.o clk-factors.o obj-y += clk-a10-hosc.o +obj-y += clk-a10-pll2.o obj-y += clk-a20-gmac.o obj-y += clk-mod0.o obj-y += clk-simple-gates.o diff --git a/drivers/clk/sunxi/clk-a10-pll2.c b/drivers/clk/sunxi/clk-a10-pll2.c new file mode 100644 index 000000000000..a57742a8576d --- /dev/null +++ b/drivers/clk/sunxi/clk-a10-pll2.c @@ -0,0 +1,188 @@ +/* + * Copyright 2013 Emilio López + * Emilio López + * + * Copyright 2015 Maxime Ripard + * Maxime Ripard + * + * 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 +#include +#include +#include + +#include + +#define SUN4I_PLL2_ENABLE 31 + +#define SUN4I_PLL2_PRE_DIV_SHIFT 0 +#define SUN4I_PLL2_PRE_DIV_WIDTH 5 +#define SUN4I_PLL2_PRE_DIV_MASK GENMASK(SUN4I_PLL2_PRE_DIV_WIDTH - 1, 0) + +#define SUN4I_PLL2_N_SHIFT 8 +#define SUN4I_PLL2_N_WIDTH 7 +#define SUN4I_PLL2_N_MASK GENMASK(SUN4I_PLL2_N_WIDTH - 1, 0) + +#define SUN4I_PLL2_POST_DIV_SHIFT 26 +#define SUN4I_PLL2_POST_DIV_WIDTH 4 +#define SUN4I_PLL2_POST_DIV_MASK GENMASK(SUN4I_PLL2_POST_DIV_WIDTH - 1, 0) + +#define SUN4I_PLL2_POST_DIV_VALUE 4 + +#define SUN4I_PLL2_OUTPUTS 4 + +static DEFINE_SPINLOCK(sun4i_a10_pll2_lock); + +static void __init sun4i_pll2_setup(struct device_node *node) +{ + const char *clk_name = node->name, *parent; + struct clk **clks, *base_clk, *prediv_clk; + struct clk_onecell_data *clk_data; + struct clk_multiplier *mult; + struct clk_gate *gate; + void __iomem *reg; + u32 val; + + reg = of_io_request_and_map(node, 0, of_node_full_name(node)); + if (IS_ERR(reg)) + return; + + clk_data = kzalloc(sizeof(*clk_data), GFP_KERNEL); + if (!clk_data) + goto err_unmap; + + clks = kcalloc(SUN4I_PLL2_OUTPUTS, sizeof(struct clk *), GFP_KERNEL); + if (!clks) + goto err_free_data; + + parent = of_clk_get_parent_name(node, 0); + prediv_clk = clk_register_divider(NULL, "pll2-prediv", + parent, 0, reg, + SUN4I_PLL2_PRE_DIV_SHIFT, + SUN4I_PLL2_PRE_DIV_WIDTH, + CLK_DIVIDER_ONE_BASED | + CLK_DIVIDER_ALLOW_ZERO, + &sun4i_a10_pll2_lock); + if (!prediv_clk) { + pr_err("Couldn't register the prediv clock\n"); + goto err_free_array; + } + + /* Setup the gate part of the PLL2 */ + gate = kzalloc(sizeof(struct clk_gate), GFP_KERNEL); + if (!gate) + goto err_unregister_prediv; + + gate->reg = reg; + gate->bit_idx = SUN4I_PLL2_ENABLE; + gate->lock = &sun4i_a10_pll2_lock; + + /* Setup the multiplier part of the PLL2 */ + mult = kzalloc(sizeof(struct clk_multiplier), GFP_KERNEL); + if (!mult) + goto err_free_gate; + + mult->reg = reg; + mult->shift = SUN4I_PLL2_N_SHIFT; + mult->width = 7; + mult->flags = CLK_MULTIPLIER_ZERO_BYPASS | + CLK_MULTIPLIER_ROUND_CLOSEST; + mult->lock = &sun4i_a10_pll2_lock; + + parent = __clk_get_name(prediv_clk); + base_clk = clk_register_composite(NULL, "pll2-base", + &parent, 1, + NULL, NULL, + &mult->hw, &clk_multiplier_ops, + &gate->hw, &clk_gate_ops, + CLK_SET_RATE_PARENT); + if (!base_clk) { + pr_err("Couldn't register the base multiplier clock\n"); + goto err_free_multiplier; + } + + parent = __clk_get_name(base_clk); + + /* + * PLL2-1x + * + * This is supposed to have a post divider, but we won't need + * to use it, we just need to initialise it to 4, and use a + * fixed divider. + */ + val = readl(reg); + val &= ~(SUN4I_PLL2_POST_DIV_MASK << SUN4I_PLL2_POST_DIV_SHIFT); + val |= SUN4I_PLL2_POST_DIV_VALUE << SUN4I_PLL2_POST_DIV_SHIFT; + writel(val, reg); + + of_property_read_string_index(node, "clock-output-names", + SUN4I_A10_PLL2_1X, &clk_name); + clks[SUN4I_A10_PLL2_1X] = clk_register_fixed_factor(NULL, clk_name, + parent, + CLK_SET_RATE_PARENT, + 1, + SUN4I_PLL2_POST_DIV_VALUE); + WARN_ON(IS_ERR(clks[SUN4I_A10_PLL2_1X])); + + /* + * PLL2-2x + * + * This clock doesn't use the post divider, and really is just + * a fixed divider from the PLL2 base clock. + */ + of_property_read_string_index(node, "clock-output-names", + SUN4I_A10_PLL2_2X, &clk_name); + clks[SUN4I_A10_PLL2_2X] = clk_register_fixed_factor(NULL, clk_name, + parent, + CLK_SET_RATE_PARENT, + 1, 2); + WARN_ON(IS_ERR(clks[SUN4I_A10_PLL2_2X])); + + /* PLL2-4x */ + of_property_read_string_index(node, "clock-output-names", + SUN4I_A10_PLL2_4X, &clk_name); + clks[SUN4I_A10_PLL2_4X] = clk_register_fixed_factor(NULL, clk_name, + parent, + CLK_SET_RATE_PARENT, + 1, 1); + WARN_ON(IS_ERR(clks[SUN4I_A10_PLL2_4X])); + + /* PLL2-8x */ + of_property_read_string_index(node, "clock-output-names", + SUN4I_A10_PLL2_8X, &clk_name); + clks[SUN4I_A10_PLL2_8X] = clk_register_fixed_factor(NULL, clk_name, + parent, + CLK_SET_RATE_PARENT, + 2, 1); + WARN_ON(IS_ERR(clks[SUN4I_A10_PLL2_8X])); + + clk_data->clks = clks; + clk_data->clk_num = SUN4I_PLL2_OUTPUTS; + of_clk_add_provider(node, of_clk_src_onecell_get, clk_data); + + return; + +err_free_multiplier: + kfree(mult); +err_free_gate: + kfree(gate); +err_unregister_prediv: + clk_unregister_divider(prediv_clk); +err_free_array: + kfree(clks); +err_free_data: + kfree(clk_data); +err_unmap: + iounmap(reg); +} +CLK_OF_DECLARE(sun4i_pll2, "allwinner,sun4i-a10-pll2-clk", sun4i_pll2_setup); diff --git a/include/dt-bindings/clock/sun4i-a10-pll2.h b/include/dt-bindings/clock/sun4i-a10-pll2.h new file mode 100644 index 000000000000..071c8112d531 --- /dev/null +++ b/include/dt-bindings/clock/sun4i-a10-pll2.h @@ -0,0 +1,53 @@ +/* + * Copyright 2015 Maxime Ripard + * + * Maxime Ripard + * + * This file is dual-licensed: you can use it either under the terms + * of the GPL or the X11 license, at your option. Note that this dual + * licensing only applies to this file, and not this project as a + * whole. + * + * a) This file 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 file 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. + * + * Or, alternatively, + * + * b) Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, + * copy, modify, merge, publish, distribute, sublicense, and/or + * sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following + * conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES + * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT + * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + */ + +#ifndef __DT_BINDINGS_CLOCK_SUN4I_A10_PLL2_H_ +#define __DT_BINDINGS_CLOCK_SUN4I_A10_PLL2_H_ + +#define SUN4I_A10_PLL2_1X 0 +#define SUN4I_A10_PLL2_2X 1 +#define SUN4I_A10_PLL2_4X 2 +#define SUN4I_A10_PLL2_8X 3 + +#endif /* __DT_BINDINGS_CLOCK_SUN4I_A10_PLL2_H_ */ -- cgit v1.2.3