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author | Maxime Ripard <maxime.ripard@free-electrons.com> | 2014-07-18 15:48:35 -0300 |
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committer | Maxime Ripard <maxime.ripard@free-electrons.com> | 2015-10-21 21:51:27 +0200 |
commit | 460d0d444822e9032a2573fc051b45c68b89a97a (patch) | |
tree | 1428651bfc2aec68811555d9155b0aa16eb66c2a /drivers/clk/sunxi | |
parent | f2e0a53271a439a2ab142645867f0cde45b2b3cd (diff) | |
download | linux-460d0d444822e9032a2573fc051b45c68b89a97a.tar.gz linux-460d0d444822e9032a2573fc051b45c68b89a97a.tar.bz2 linux-460d0d444822e9032a2573fc051b45c68b89a97a.zip |
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 <maxime.ripard@free-electrons.com>
Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Diffstat (limited to 'drivers/clk/sunxi')
-rw-r--r-- | drivers/clk/sunxi/Makefile | 1 | ||||
-rw-r--r-- | drivers/clk/sunxi/clk-a10-pll2.c | 188 |
2 files changed, 189 insertions, 0 deletions
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 <emilio@elopez.com.ar> + * + * Copyright 2015 Maxime Ripard + * Maxime Ripard <maxime.ripard@free-electrons.com> + * + * 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/of.h> +#include <linux/of_address.h> +#include <linux/slab.h> + +#include <dt-bindings/clock/sun4i-a10-pll2.h> + +#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); |