diff options
Diffstat (limited to 'drivers/clk/sunxi-ng')
| -rw-r--r-- | drivers/clk/sunxi-ng/Kconfig | 4 | ||||
| -rw-r--r-- | drivers/clk/sunxi-ng/Makefile | 1 | ||||
| -rw-r--r-- | drivers/clk/sunxi-ng/ccu_nk.c | 147 | ||||
| -rw-r--r-- | drivers/clk/sunxi-ng/ccu_nk.h | 71 |
4 files changed, 223 insertions, 0 deletions
diff --git a/drivers/clk/sunxi-ng/Kconfig b/drivers/clk/sunxi-ng/Kconfig index fc970b5a28c6..2eb0fc6b41d5 100644 --- a/drivers/clk/sunxi-ng/Kconfig +++ b/drivers/clk/sunxi-ng/Kconfig @@ -24,6 +24,10 @@ config SUNXI_CCU_PHASE # Multi-factor clocks +config SUNXI_CCU_NK + bool + 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 501dec9451f4..22951e60f876 100644 --- a/drivers/clk/sunxi-ng/Makefile +++ b/drivers/clk/sunxi-ng/Makefile @@ -10,4 +10,5 @@ obj-$(CONFIG_SUNXI_CCU_MUX) += ccu_mux.o obj-$(CONFIG_SUNXI_CCU_PHASE) += ccu_phase.o # Multi-factor clocks +obj-$(CONFIG_SUNXI_CCU_NK) += ccu_nk.o obj-$(CONFIG_SUNXI_CCU_MP) += ccu_mp.o diff --git a/drivers/clk/sunxi-ng/ccu_nk.c b/drivers/clk/sunxi-ng/ccu_nk.c new file mode 100644 index 000000000000..4470ffc8cf0d --- /dev/null +++ b/drivers/clk/sunxi-ng/ccu_nk.c @@ -0,0 +1,147 @@ +/* + * 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_gate.h" +#include "ccu_nk.h" + +void ccu_nk_find_best(unsigned long parent, unsigned long rate, + unsigned int max_n, unsigned int max_k, + unsigned int *n, unsigned int *k) +{ + unsigned long best_rate = 0; + unsigned int best_k = 0, best_n = 0; + unsigned int _k, _n; + + for (_k = 1; _k <= max_k; _k++) { + for (_n = 1; _n <= max_n; _n++) { + unsigned long tmp_rate = parent * _n * _k; + + if (tmp_rate > rate) + continue; + + if ((rate - tmp_rate) < (rate - best_rate)) { + best_rate = tmp_rate; + best_k = _k; + best_n = _n; + } + } + } + + *k = best_k; + *n = best_n; +} + +static void ccu_nk_disable(struct clk_hw *hw) +{ + struct ccu_nk *nk = hw_to_ccu_nk(hw); + + return ccu_gate_helper_disable(&nk->common, nk->enable); +} + +static int ccu_nk_enable(struct clk_hw *hw) +{ + struct ccu_nk *nk = hw_to_ccu_nk(hw); + + return ccu_gate_helper_enable(&nk->common, nk->enable); +} + +static int ccu_nk_is_enabled(struct clk_hw *hw) +{ + struct ccu_nk *nk = hw_to_ccu_nk(hw); + + return ccu_gate_helper_is_enabled(&nk->common, nk->enable); +} + +static unsigned long ccu_nk_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct ccu_nk *nk = hw_to_ccu_nk(hw); + unsigned long rate, n, k; + u32 reg; + + reg = readl(nk->common.base + nk->common.reg); + + n = reg >> nk->n.shift; + n &= (1 << nk->n.width) - 1; + + k = reg >> nk->k.shift; + k &= (1 << nk->k.width) - 1; + + rate = parent_rate * (n + 1) * (k + 1); + + if (nk->common.features & CCU_FEATURE_FIXED_POSTDIV) + rate /= nk->fixed_post_div; + + return rate; +} + +static long ccu_nk_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + struct ccu_nk *nk = hw_to_ccu_nk(hw); + unsigned int n, k; + + if (nk->common.features & CCU_FEATURE_FIXED_POSTDIV) + rate *= nk->fixed_post_div; + + ccu_nk_find_best(*parent_rate, rate, + 1 << nk->n.width, 1 << nk->k.width, + &n, &k); + + rate = *parent_rate * n * k; + if (nk->common.features & CCU_FEATURE_FIXED_POSTDIV) + rate = rate / nk->fixed_post_div; + + return rate; +} + +static int ccu_nk_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct ccu_nk *nk = hw_to_ccu_nk(hw); + unsigned long flags; + unsigned int n, k; + u32 reg; + + if (nk->common.features & CCU_FEATURE_FIXED_POSTDIV) + rate = rate * nk->fixed_post_div; + + ccu_nk_find_best(parent_rate, rate, + 1 << nk->n.width, 1 << nk->k.width, + &n, &k); + + spin_lock_irqsave(nk->common.lock, flags); + + reg = readl(nk->common.base + nk->common.reg); + reg &= ~GENMASK(nk->n.width + nk->n.shift - 1, nk->n.shift); + reg &= ~GENMASK(nk->k.width + nk->k.shift - 1, nk->k.shift); + + writel(reg | ((k - 1) << nk->k.shift) | ((n - 1) << nk->n.shift), + nk->common.base + nk->common.reg); + + spin_unlock_irqrestore(nk->common.lock, flags); + + ccu_helper_wait_for_lock(&nk->common, nk->lock); + + return 0; +} + +const struct clk_ops ccu_nk_ops = { + .disable = ccu_nk_disable, + .enable = ccu_nk_enable, + .is_enabled = ccu_nk_is_enabled, + + .recalc_rate = ccu_nk_recalc_rate, + .round_rate = ccu_nk_round_rate, + .set_rate = ccu_nk_set_rate, +}; diff --git a/drivers/clk/sunxi-ng/ccu_nk.h b/drivers/clk/sunxi-ng/ccu_nk.h new file mode 100644 index 000000000000..4b52da0c29fe --- /dev/null +++ b/drivers/clk/sunxi-ng/ccu_nk.h @@ -0,0 +1,71 @@ +/* + * 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_NK_H_ +#define _CCU_NK_H_ + +#include <linux/clk-provider.h> + +#include "ccu_common.h" +#include "ccu_div.h" +#include "ccu_mult.h" + +/* + * struct ccu_nk - Definition of an N-K clock + * + * Clocks based on the formula parent * N * K + */ +struct ccu_nk { + u16 reg; + u32 enable; + u32 lock; + + struct _ccu_mult n; + struct _ccu_mult k; + + unsigned int fixed_post_div; + + struct ccu_common common; +}; + +#define SUNXI_CCU_NK_WITH_GATE_LOCK_POSTDIV(_struct, _name, _parent, _reg, \ + _nshift, _nwidth, \ + _kshift, _kwidth, \ + _gate, _lock, _postdiv, \ + _flags) \ + struct ccu_nk _struct = { \ + .enable = _gate, \ + .lock = _lock, \ + .k = _SUNXI_CCU_MULT(_kshift, _kwidth), \ + .n = _SUNXI_CCU_MULT(_nshift, _nwidth), \ + .fixed_post_div = _postdiv, \ + .common = { \ + .reg = _reg, \ + .features = CCU_FEATURE_FIXED_POSTDIV, \ + .hw.init = CLK_HW_INIT(_name, \ + _parent, \ + &ccu_nk_ops, \ + _flags), \ + }, \ + } + +static inline struct ccu_nk *hw_to_ccu_nk(struct clk_hw *hw) +{ + struct ccu_common *common = hw_to_ccu_common(hw); + + return container_of(common, struct ccu_nk, common); +} + +extern const struct clk_ops ccu_nk_ops; + +#endif /* _CCU_NK_H_ */ |