[PATCH v2 09/15] clk: sunxi-ng: Add M-P factor clock support
Maxime Ripard
maxime.ripard at free-electrons.com
Tue Jun 7 13:41:48 PDT 2016
Introduce support for the clocks that combine a linear divider and a
power-of-two based one.
Signed-off-by: Maxime Ripard <maxime.ripard at free-electrons.com>
---
drivers/clk/sunxi-ng/Makefile | 1 +
drivers/clk/sunxi-ng/ccu_mp.c | 158 ++++++++++++++++++++++++++++++++++++++++++
drivers/clk/sunxi-ng/ccu_mp.h | 78 +++++++++++++++++++++
3 files changed, 237 insertions(+)
create mode 100644 drivers/clk/sunxi-ng/ccu_mp.c
create mode 100644 drivers/clk/sunxi-ng/ccu_mp.h
diff --git a/drivers/clk/sunxi-ng/Makefile b/drivers/clk/sunxi-ng/Makefile
index 67a2559fe283..2aeccdb26e3f 100644
--- a/drivers/clk/sunxi-ng/Makefile
+++ b/drivers/clk/sunxi-ng/Makefile
@@ -6,5 +6,6 @@ obj-y += ccu_frac.o
obj-y += ccu_div.o
obj-y += ccu_fixed_factor.o
obj-y += ccu_gate.o
+obj-y += ccu_mp.o
obj-y += ccu_mux.o
obj-y += ccu_phase.o
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 at 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,
+};
diff --git a/drivers/clk/sunxi-ng/ccu_mp.h b/drivers/clk/sunxi-ng/ccu_mp.h
new file mode 100644
index 000000000000..2f96e685b98e
--- /dev/null
+++ b/drivers/clk/sunxi-ng/ccu_mp.h
@@ -0,0 +1,78 @@
+/*
+ * 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_MP_H_
+#define _CCU_MP_H_
+
+#include <linux/clk-provider.h>
+
+#include "ccu_common.h"
+#include "ccu_div.h"
+#include "ccu_mult.h"
+#include "ccu_mux.h"
+
+/*
+ * struct ccu_mp - Definition of an M-P clock
+ *
+ * Clocks based on the formula parent >> P / M
+ */
+struct ccu_mp {
+ u32 enable;
+
+ struct _ccu_div m;
+ struct _ccu_div p;
+ struct ccu_mux_internal mux;
+ struct ccu_common common;
+};
+
+#define SUNXI_CCU_MP_WITH_MUX_GATE(_struct, _name, _parents, _reg, \
+ _mshift, _mwidth, \
+ _pshift, _pwidth, \
+ _muxshift, _muxwidth, \
+ _gate, _flags) \
+ struct ccu_mp _struct = { \
+ .enable = _gate, \
+ .m = _SUNXI_CCU_DIV(_mshift, _mwidth), \
+ .p = _SUNXI_CCU_DIV(_pshift, _pwidth), \
+ .mux = SUNXI_CLK_MUX(_muxshift, _muxwidth), \
+ .common = { \
+ .reg = _reg, \
+ .features = CCU_FEATURE_GATE, \
+ .hw.init = SUNXI_HW_INIT_PARENTS(_name, \
+ _parents, \
+ &ccu_mp_ops, \
+ _flags), \
+ } \
+ }
+
+#define SUNXI_CCU_MP_WITH_MUX(_struct, _name, _parents, _reg, \
+ _mshift, _mwidth, \
+ _pshift, _pwidth, \
+ _muxshift, _muxwidth, \
+ _flags) \
+ SUNXI_CCU_MP_WITH_MUX_GATE(_struct, _name, _parents, _reg, \
+ _mshift, _mwidth, \
+ _pshift, _pwidth, \
+ _muxshift, _muxwidth, \
+ 0, _flags)
+
+static inline struct ccu_mp *hw_to_ccu_mp(struct clk_hw *hw)
+{
+ struct ccu_common *common = hw_to_ccu_common(hw);
+
+ return container_of(common, struct ccu_mp, common);
+}
+
+extern const struct clk_ops ccu_mp_ops;
+
+#endif /* _CCU_MP_H_ */
--
2.8.3
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