diff options
author | Maxime Ripard <maxime.ripard@free-electrons.com> | 2016-06-29 22:05:31 +0300 |
---|---|---|
committer | Michael Turquette <mturquette@baylibre.com> | 2016-07-09 04:05:00 +0300 |
commit | 6174a1e24b0d13f85f64ff570e9d4efc6b0d6287 (patch) | |
tree | d5949cf527ca41aa26f69c0bcc4dc3f0414fa70f /drivers/clk/sunxi-ng | |
parent | adbfb0056e03d556b98ffe93da0d7126bd630096 (diff) | |
download | linux-6174a1e24b0d13f85f64ff570e9d4efc6b0d6287.tar.xz |
clk: sunxi-ng: Add N-M-factor clock support
Introduce support for clocks that multiply and divide using linear factors.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
Link: lkml.kernel.org/r/20160629190535.11855-11-maxime.ripard@free-electrons.com
Diffstat (limited to 'drivers/clk/sunxi-ng')
-rw-r--r-- | drivers/clk/sunxi-ng/Kconfig | 6 | ||||
-rw-r--r-- | drivers/clk/sunxi-ng/Makefile | 1 | ||||
-rw-r--r-- | drivers/clk/sunxi-ng/ccu_nm.c | 114 | ||||
-rw-r--r-- | drivers/clk/sunxi-ng/ccu_nm.h | 91 |
4 files changed, 212 insertions, 0 deletions
diff --git a/drivers/clk/sunxi-ng/Kconfig b/drivers/clk/sunxi-ng/Kconfig index 2eb0fc6b41d5..d8a5da270778 100644 --- a/drivers/clk/sunxi-ng/Kconfig +++ b/drivers/clk/sunxi-ng/Kconfig @@ -28,6 +28,12 @@ config SUNXI_CCU_NK bool select SUNXI_CCU_GATE +config SUNXI_CCU_NM + bool + select RATIONAL + select SUNXI_CCU_FRAC + select SUNXI_CCU_GATE + config SUNXI_CCU_MP bool select SUNXI_CCU_GATE diff --git a/drivers/clk/sunxi-ng/Makefile b/drivers/clk/sunxi-ng/Makefile index 22951e60f876..7d2cd2a47a39 100644 --- a/drivers/clk/sunxi-ng/Makefile +++ b/drivers/clk/sunxi-ng/Makefile @@ -11,4 +11,5 @@ obj-$(CONFIG_SUNXI_CCU_PHASE) += ccu_phase.o # Multi-factor clocks obj-$(CONFIG_SUNXI_CCU_NK) += ccu_nk.o +obj-$(CONFIG_SUNXI_CCU_NM) += ccu_nm.o obj-$(CONFIG_SUNXI_CCU_MP) += ccu_mp.o diff --git a/drivers/clk/sunxi-ng/ccu_nm.c b/drivers/clk/sunxi-ng/ccu_nm.c new file mode 100644 index 000000000000..e35ddd8eec8b --- /dev/null +++ b/drivers/clk/sunxi-ng/ccu_nm.c @@ -0,0 +1,114 @@ +/* + * Copyright (C) 2016 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. + */ + +#include <linux/clk-provider.h> +#include <linux/rational.h> + +#include "ccu_frac.h" +#include "ccu_gate.h" +#include "ccu_nm.h" + +static void ccu_nm_disable(struct clk_hw *hw) +{ + struct ccu_nm *nm = hw_to_ccu_nm(hw); + + return ccu_gate_helper_disable(&nm->common, nm->enable); +} + +static int ccu_nm_enable(struct clk_hw *hw) +{ + struct ccu_nm *nm = hw_to_ccu_nm(hw); + + return ccu_gate_helper_enable(&nm->common, nm->enable); +} + +static int ccu_nm_is_enabled(struct clk_hw *hw) +{ + struct ccu_nm *nm = hw_to_ccu_nm(hw); + + return ccu_gate_helper_is_enabled(&nm->common, nm->enable); +} + +static unsigned long ccu_nm_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct ccu_nm *nm = hw_to_ccu_nm(hw); + unsigned long n, m; + u32 reg; + + if (ccu_frac_helper_is_enabled(&nm->common, &nm->frac)) + return ccu_frac_helper_read_rate(&nm->common, &nm->frac); + + reg = readl(nm->common.base + nm->common.reg); + + n = reg >> nm->n.shift; + n &= (1 << nm->n.width) - 1; + + m = reg >> nm->m.shift; + m &= (1 << nm->m.width) - 1; + + return parent_rate * (n + 1) / (m + 1); +} + +static long ccu_nm_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + struct ccu_nm *nm = hw_to_ccu_nm(hw); + unsigned long n, m; + + rational_best_approximation(rate, *parent_rate, + 1 << nm->n.width, 1 << nm->m.width, + &n, &m); + + return *parent_rate * n / m; +} + +static int ccu_nm_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct ccu_nm *nm = hw_to_ccu_nm(hw); + unsigned long flags; + unsigned long n, m; + u32 reg; + + if (ccu_frac_helper_has_rate(&nm->common, &nm->frac, rate)) + return ccu_frac_helper_set_rate(&nm->common, &nm->frac, rate); + else + ccu_frac_helper_disable(&nm->common, &nm->frac); + + rational_best_approximation(rate, parent_rate, + 1 << nm->n.width, 1 << nm->m.width, + &n, &m); + + spin_lock_irqsave(nm->common.lock, flags); + + reg = readl(nm->common.base + nm->common.reg); + reg &= ~GENMASK(nm->n.width + nm->n.shift - 1, nm->n.shift); + reg &= ~GENMASK(nm->m.width + nm->m.shift - 1, nm->m.shift); + + writel(reg | ((m - 1) << nm->m.shift) | ((n - 1) << nm->n.shift), + nm->common.base + nm->common.reg); + + spin_unlock_irqrestore(nm->common.lock, flags); + + ccu_helper_wait_for_lock(&nm->common, nm->lock); + + return 0; +} + +const struct clk_ops ccu_nm_ops = { + .disable = ccu_nm_disable, + .enable = ccu_nm_enable, + .is_enabled = ccu_nm_is_enabled, + + .recalc_rate = ccu_nm_recalc_rate, + .round_rate = ccu_nm_round_rate, + .set_rate = ccu_nm_set_rate, +}; diff --git a/drivers/clk/sunxi-ng/ccu_nm.h b/drivers/clk/sunxi-ng/ccu_nm.h new file mode 100644 index 000000000000..0b7bcd33a2df --- /dev/null +++ b/drivers/clk/sunxi-ng/ccu_nm.h @@ -0,0 +1,91 @@ +/* + * Copyright (c) 2016 Maxime Ripard. All rights reserved. + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * 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. + */ + +#ifndef _CCU_NM_H_ +#define _CCU_NM_H_ + +#include <linux/clk-provider.h> + +#include "ccu_common.h" +#include "ccu_div.h" +#include "ccu_frac.h" +#include "ccu_mult.h" + +/* + * struct ccu_nm - Definition of an N-M clock + * + * Clocks based on the formula parent * N / M + */ +struct ccu_nm { + u32 enable; + u32 lock; + + struct _ccu_mult n; + struct _ccu_div m; + struct _ccu_frac frac; + + struct ccu_common common; +}; + +#define SUNXI_CCU_NM_WITH_FRAC_GATE_LOCK(_struct, _name, _parent, _reg, \ + _nshift, _nwidth, \ + _mshift, _mwidth, \ + _frac_en, _frac_sel, \ + _frac_rate_0, _frac_rate_1, \ + _gate, _lock, _flags) \ + struct ccu_nm _struct = { \ + .enable = _gate, \ + .lock = _lock, \ + .n = _SUNXI_CCU_MULT(_nshift, _nwidth), \ + .m = _SUNXI_CCU_DIV(_mshift, _mwidth), \ + .frac = _SUNXI_CCU_FRAC(_frac_en, _frac_sel, \ + _frac_rate_0, \ + _frac_rate_1), \ + .common = { \ + .reg = _reg, \ + .features = CCU_FEATURE_FRACTIONAL, \ + .hw.init = CLK_HW_INIT(_name, \ + _parent, \ + &ccu_nm_ops, \ + _flags), \ + }, \ + } + +#define SUNXI_CCU_NM_WITH_GATE_LOCK(_struct, _name, _parent, _reg, \ + _nshift, _nwidth, \ + _mshift, _mwidth, \ + _gate, _lock, _flags) \ + struct ccu_nm _struct = { \ + .enable = _gate, \ + .lock = _lock, \ + .n = _SUNXI_CCU_MULT(_nshift, _nwidth), \ + .m = _SUNXI_CCU_DIV(_mshift, _mwidth), \ + .common = { \ + .reg = _reg, \ + .hw.init = CLK_HW_INIT(_name, \ + _parent, \ + &ccu_nm_ops, \ + _flags), \ + }, \ + } + +static inline struct ccu_nm *hw_to_ccu_nm(struct clk_hw *hw) +{ + struct ccu_common *common = hw_to_ccu_common(hw); + + return container_of(common, struct ccu_nm, common); +} + +extern const struct clk_ops ccu_nm_ops; + +#endif /* _CCU_NM_H_ */ |