From mboxrd@z Thu Jan 1 00:00:00 1970 From: maxime.ripard@free-electrons.com (Maxime Ripard) Date: Sun, 8 May 2016 22:01:48 +0200 Subject: [PATCH 13/16] clk: sunxi-ng: Add N-K-M Factor clock In-Reply-To: <1462737711-10017-1-git-send-email-maxime.ripard@free-electrons.com> References: <1462737711-10017-1-git-send-email-maxime.ripard@free-electrons.com> Message-ID: <1462737711-10017-14-git-send-email-maxime.ripard@free-electrons.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Introduce support for clocks that multiply and divide using two linear multipliers and one linear divider. Signed-off-by: Maxime Ripard --- drivers/clk/sunxi-ng/Makefile | 1 + drivers/clk/sunxi-ng/ccu_nkm.c | 144 +++++++++++++++++++++++++++++++++++++++++ drivers/clk/sunxi-ng/ccu_nkm.h | 42 ++++++++++++ 3 files changed, 187 insertions(+) create mode 100644 drivers/clk/sunxi-ng/ccu_nkm.c create mode 100644 drivers/clk/sunxi-ng/ccu_nkm.h diff --git a/drivers/clk/sunxi-ng/Makefile b/drivers/clk/sunxi-ng/Makefile index fba64c7f4fcd..2bb8bc22e907 100644 --- a/drivers/clk/sunxi-ng/Makefile +++ b/drivers/clk/sunxi-ng/Makefile @@ -8,6 +8,7 @@ obj-y += ccu_m.o obj-y += ccu_mp.o obj-y += ccu_mux.o obj-y += ccu_nk.o +obj-y += ccu_nkm.o obj-y += ccu_nm.o obj-y += ccu_p.o obj-y += ccu_phase.o diff --git a/drivers/clk/sunxi-ng/ccu_nkm.c b/drivers/clk/sunxi-ng/ccu_nkm.c new file mode 100644 index 000000000000..9019c7f6988c --- /dev/null +++ b/drivers/clk/sunxi-ng/ccu_nkm.c @@ -0,0 +1,144 @@ +/* + * Copyright (C) 2016 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. + */ + +#include +#include + +#include "ccu_gate.h" +#include "ccu_nkm.h" + +void ccu_nkm_find_best(unsigned long parent, unsigned long rate, + unsigned long max_n, unsigned long max_k, unsigned long max_m, + unsigned long *n, unsigned long *k, unsigned long *m) +{ + unsigned long best_rate = 0; + unsigned long best_n = 0, best_k = 0, best_m = 0; + unsigned long _n, _k, _m; + + for (_k = 1; _k <= max_k; _k++) { + unsigned long tmp_rate; + + rational_best_approximation(rate / _k, parent, + max_n, max_m, &_n, &_m); + + tmp_rate = parent * _n * _k / _m; + + if (tmp_rate > rate) + continue; + + if ((rate - tmp_rate) < (rate - best_rate)) { + best_rate = tmp_rate; + best_n = _n; + best_k = _k; + best_m = _m; + } + } + + *n = best_n; + *k = best_k; + *m = best_m; +} + +static void ccu_nkm_disable(struct clk_hw *hw) +{ + struct ccu_nkm *nkm = hw_to_ccu_nkm(hw); + + return ccu_gate_helper_disable(&nkm->common, nkm->enable); +} + +static int ccu_nkm_enable(struct clk_hw *hw) +{ + struct ccu_nkm *nkm = hw_to_ccu_nkm(hw); + + return ccu_gate_helper_enable(&nkm->common, nkm->enable); +} + +static int ccu_nkm_is_enabled(struct clk_hw *hw) +{ + struct ccu_nkm *nkm = hw_to_ccu_nkm(hw); + + return ccu_gate_helper_is_enabled(&nkm->common, nkm->enable); +} + +static unsigned long ccu_nkm_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct ccu_nkm *nkm = hw_to_ccu_nkm(hw); + unsigned long n, m, k; + u32 reg; + + reg = readl(nkm->common.base + nkm->common.reg); + + n = reg >> nkm->n.shift; + n &= (1 << nkm->n.width) - 1; + + k = reg >> nkm->k.shift; + k &= (1 << nkm->k.width) - 1; + + m = reg >> nkm->m.shift; + m &= (1 << nkm->m.width) - 1; + + return parent_rate * (n + 1) * (k + 1) / (m + 1); +} + +static long ccu_nkm_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + struct ccu_nkm *nkm = hw_to_ccu_nkm(hw); + unsigned long n, k, m; + + ccu_nkm_find_best(*parent_rate, rate, 1 << nkm->n.width, + 1 << nkm->k.width, 1 << nkm->m.width, + &n, &k, &m); + + return *parent_rate * n * k / m; +} + +static int ccu_nkm_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct ccu_nkm *nkm = hw_to_ccu_nkm(hw); + unsigned long n, k, m; + unsigned long flags; + u32 reg; + + ccu_nkm_find_best(parent_rate, rate, 1 << nkm->n.width, + 1 << nkm->k.width, 1 << nkm->m.width, + &n, &k, &m); + + spin_lock_irqsave(nkm->common.lock, flags); + + reg = readl(nkm->common.base + nkm->common.reg); + reg &= ~GENMASK(nkm->n.width + nkm->n.shift, nkm->n.shift); + reg &= ~GENMASK(nkm->k.width + nkm->k.shift, nkm->k.shift); + reg &= ~GENMASK(nkm->m.width + nkm->m.shift, nkm->m.shift); + + reg |= (n - 1) << nkm->m.shift; + reg |= (k - 1) << nkm->m.shift; + reg |= (m - 1) << nkm->m.shift; + + writel(reg, nkm->common.base + nkm->common.reg); + + spin_unlock_irqrestore(nkm->common.lock, flags); + + ccu_helper_wait_for_lock(&nkm->common, nkm->lock); + + return 0; +} + +const struct clk_ops ccu_nkm_ops = { + .disable = ccu_nkm_disable, + .enable = ccu_nkm_enable, + .is_enabled = ccu_nkm_is_enabled, + + .recalc_rate = ccu_nkm_recalc_rate, + .round_rate = ccu_nkm_round_rate, + .set_rate = ccu_nkm_set_rate, +}; diff --git a/drivers/clk/sunxi-ng/ccu_nkm.h b/drivers/clk/sunxi-ng/ccu_nkm.h new file mode 100644 index 000000000000..1301e9f08305 --- /dev/null +++ b/drivers/clk/sunxi-ng/ccu_nkm.h @@ -0,0 +1,42 @@ +/* + * 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_NKM_H_ +#define _CCU_NKM_H_ + +#include + +#include "ccu_factor.h" +#include "ccu_common.h" + +struct ccu_nkm { + u32 enable; + u32 lock; + + struct ccu_factor n; + struct ccu_factor k; + struct ccu_factor m; + + struct ccu_common common; +}; + +static inline struct ccu_nkm *hw_to_ccu_nkm(struct clk_hw *hw) +{ + struct ccu_common *common = hw_to_ccu_common(hw); + + return container_of(common, struct ccu_nkm, common); +} + +extern const struct clk_ops ccu_nkm_ops; + +#endif /* _CCU_NKM_H_ */ -- 2.8.2