diff options
Diffstat (limited to 'drivers/clk/sunxi-ng/ccu_mp.c')
| -rw-r--r-- | drivers/clk/sunxi-ng/ccu_mp.c | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/drivers/clk/sunxi-ng/ccu_mp.c b/drivers/clk/sunxi-ng/ccu_mp.c new file mode 100644 index 000000000000..cbf33ef5faa9 --- /dev/null +++ b/drivers/clk/sunxi-ng/ccu_mp.c @@ -0,0 +1,158 @@ +/* + * 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 "ccu_gate.h" +#include "ccu_mp.h" + +static void ccu_mp_find_best(unsigned long parent, unsigned long rate, + unsigned int max_m, unsigned int max_p, + unsigned int *m, unsigned int *p) +{ + unsigned long best_rate = 0; + unsigned int best_m = 0, best_p = 0; + unsigned int _m, _p; + + for (_p = 0; _p <= max_p; _p++) { + for (_m = 1; _m <= max_m; _m++) { + unsigned long tmp_rate = (parent >> _p) / _m; + + if (tmp_rate > rate) + continue; + + if ((rate - tmp_rate) < (rate - best_rate)) { + best_rate = tmp_rate; + best_m = _m; + best_p = _p; + } + } + } + + *m = best_m; + *p = best_p; +} + +static unsigned long ccu_mp_round_rate(struct ccu_mux_internal *mux, + unsigned long parent_rate, + unsigned long rate, + void *data) +{ + struct ccu_mp *cmp = data; + unsigned int m, p; + + ccu_mp_find_best(parent_rate, rate, + 1 << cmp->m.width, (1 << cmp->p.width) - 1, + &m, &p); + + return (parent_rate >> p) / m; +} + +static void ccu_mp_disable(struct clk_hw *hw) +{ + struct ccu_mp *cmp = hw_to_ccu_mp(hw); + + return ccu_gate_helper_disable(&cmp->common, cmp->enable); +} + +static int ccu_mp_enable(struct clk_hw *hw) +{ + struct ccu_mp *cmp = hw_to_ccu_mp(hw); + + return ccu_gate_helper_enable(&cmp->common, cmp->enable); +} + +static int ccu_mp_is_enabled(struct clk_hw *hw) +{ + struct ccu_mp *cmp = hw_to_ccu_mp(hw); + + return ccu_gate_helper_is_enabled(&cmp->common, cmp->enable); +} + +static unsigned long ccu_mp_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct ccu_mp *cmp = hw_to_ccu_mp(hw); + unsigned int m, p; + u32 reg; + + reg = readl(cmp->common.base + cmp->common.reg); + + m = reg >> cmp->m.shift; + m &= (1 << cmp->m.width) - 1; + + p = reg >> cmp->p.shift; + p &= (1 << cmp->p.width) - 1; + + return (parent_rate >> p) / (m + 1); +} + +static int ccu_mp_determine_rate(struct clk_hw *hw, + struct clk_rate_request *req) +{ + struct ccu_mp *cmp = hw_to_ccu_mp(hw); + + return ccu_mux_helper_determine_rate(&cmp->common, &cmp->mux, + req, ccu_mp_round_rate, cmp); +} + +static int ccu_mp_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct ccu_mp *cmp = hw_to_ccu_mp(hw); + unsigned long flags; + unsigned int m, p; + u32 reg; + + ccu_mp_find_best(parent_rate, rate, + 1 << cmp->m.width, (1 << cmp->p.width) - 1, + &m, &p); + + + spin_lock_irqsave(cmp->common.lock, flags); + + reg = readl(cmp->common.base + cmp->common.reg); + reg &= ~GENMASK(cmp->m.width + cmp->m.shift - 1, cmp->m.shift); + reg &= ~GENMASK(cmp->p.width + cmp->p.shift - 1, cmp->p.shift); + + writel(reg | (p << cmp->p.shift) | ((m - 1) << cmp->m.shift), + cmp->common.base + cmp->common.reg); + + spin_unlock_irqrestore(cmp->common.lock, flags); + + return 0; +} + +static u8 ccu_mp_get_parent(struct clk_hw *hw) +{ + struct ccu_mp *cmp = hw_to_ccu_mp(hw); + + return ccu_mux_helper_get_parent(&cmp->common, &cmp->mux); +} + +static int ccu_mp_set_parent(struct clk_hw *hw, u8 index) +{ + struct ccu_mp *cmp = hw_to_ccu_mp(hw); + + return ccu_mux_helper_set_parent(&cmp->common, &cmp->mux, index); +} + +const struct clk_ops ccu_mp_ops = { + .disable = ccu_mp_disable, + .enable = ccu_mp_enable, + .is_enabled = ccu_mp_is_enabled, + + .get_parent = ccu_mp_get_parent, + .set_parent = ccu_mp_set_parent, + + .determine_rate = ccu_mp_determine_rate, + .recalc_rate = ccu_mp_recalc_rate, + .set_rate = ccu_mp_set_rate, +}; |