[PATCH 12/16] clk: sunxi-ng: Add N-M-factor clock support
From: Maxime Ripard <hidden>
Date: 2016-05-08 20:01:47
Also in:
linux-clk
Subsystem:
arm/allwinner sunxi soc support, common clk framework, the rest · Maintainers:
Chen-Yu Tsai, Jernej Skrabec, Samuel Holland, Michael Turquette, Stephen Boyd, Linus Torvalds
Introduce support for clocks that multiply and divide using linear factors. Signed-off-by: Maxime Ripard <redacted> --- drivers/clk/sunxi-ng/Makefile | 1 + drivers/clk/sunxi-ng/ccu_nm.c | 103 ++++++++++++++++++++++++++++++++++++++++++ drivers/clk/sunxi-ng/ccu_nm.h | 41 +++++++++++++++++ 3 files changed, 145 insertions(+) create mode 100644 drivers/clk/sunxi-ng/ccu_nm.c create mode 100644 drivers/clk/sunxi-ng/ccu_nm.h
diff --git a/drivers/clk/sunxi-ng/Makefile b/drivers/clk/sunxi-ng/Makefile
index e29ddae99653..fba64c7f4fcd 100644
--- a/drivers/clk/sunxi-ng/Makefile
+++ b/drivers/clk/sunxi-ng/Makefile@@ -8,5 +8,6 @@ obj-y += ccu_m.o obj-y += ccu_mp.o obj-y += ccu_mux.o obj-y += ccu_nk.o +obj-y += ccu_nm.o obj-y += ccu_p.o obj-y += ccu_phase.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..268637db137b
--- /dev/null
+++ b/drivers/clk/sunxi-ng/ccu_nm.c@@ -0,0 +1,103 @@ +/* + * 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_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; + + 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, + nm->n.width, 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; + + rational_best_approximation(rate, parent_rate, + nm->n.width, 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, nm->n.shift); + reg &= ~GENMASK(nm->m.width + nm->m.shift, 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..6fda3ed05cd8
--- /dev/null
+++ b/drivers/clk/sunxi-ng/ccu_nm.h@@ -0,0 +1,41 @@ +/* + * 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_factor.h" +#include "ccu_common.h" + +struct ccu_nm { + u32 enable; + u32 lock; + + struct ccu_factor n; + struct ccu_factor m; + + struct ccu_common common; +}; + +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_ */
--
2.8.2