clk: sunxi-ng: Add N-class clocks support

Add support for the class with a single factor, N, being a multiplier.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>

drivers/clk/sunxi-ng/ccu_mult.c

@@ -0,0 +1,133 @@
+/*
+ * 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_mult.h"
+
+static void ccu_mult_find_best(unsigned long parent, unsigned long rate,
+			       unsigned int max_n, unsigned int *n)
+{
+	*n = rate / parent;
+}
+
+static unsigned long ccu_mult_round_rate(struct ccu_mux_internal *mux,
+					unsigned long parent_rate,
+					unsigned long rate,
+					void *data)
+{
+	struct ccu_mult *cm = data;
+	unsigned int n;
+
+	ccu_mult_find_best(parent_rate, rate, 1 << cm->mult.width, &n);
+
+	return parent_rate * n;
+}
+
+static void ccu_mult_disable(struct clk_hw *hw)
+{
+	struct ccu_mult *cm = hw_to_ccu_mult(hw);
+
+	return ccu_gate_helper_disable(&cm->common, cm->enable);
+}
+
+static int ccu_mult_enable(struct clk_hw *hw)
+{
+	struct ccu_mult *cm = hw_to_ccu_mult(hw);
+
+	return ccu_gate_helper_enable(&cm->common, cm->enable);
+}
+
+static int ccu_mult_is_enabled(struct clk_hw *hw)
+{
+	struct ccu_mult *cm = hw_to_ccu_mult(hw);
+
+	return ccu_gate_helper_is_enabled(&cm->common, cm->enable);
+}
+
+static unsigned long ccu_mult_recalc_rate(struct clk_hw *hw,
+					unsigned long parent_rate)
+{
+	struct ccu_mult *cm = hw_to_ccu_mult(hw);
+	unsigned long val;
+	u32 reg;
+
+	reg = readl(cm->common.base + cm->common.reg);
+	val = reg >> cm->mult.shift;
+	val &= (1 << cm->mult.width) - 1;
+
+	ccu_mux_helper_adjust_parent_for_prediv(&cm->common, &cm->mux, -1,
+						&parent_rate);
+
+	return parent_rate * (val + 1);
+}
+
+static int ccu_mult_determine_rate(struct clk_hw *hw,
+				struct clk_rate_request *req)
+{
+	struct ccu_mult *cm = hw_to_ccu_mult(hw);
+
+	return ccu_mux_helper_determine_rate(&cm->common, &cm->mux,
+					     req, ccu_mult_round_rate, cm);
+}
+
+static int ccu_mult_set_rate(struct clk_hw *hw, unsigned long rate,
+			   unsigned long parent_rate)
+{
+	struct ccu_mult *cm = hw_to_ccu_mult(hw);
+	unsigned long flags;
+	unsigned int n;
+	u32 reg;
+
+	ccu_mux_helper_adjust_parent_for_prediv(&cm->common, &cm->mux, -1,
+						&parent_rate);
+
+	ccu_mult_find_best(parent_rate, rate, 1 << cm->mult.width, &n);
+
+	spin_lock_irqsave(cm->common.lock, flags);
+
+	reg = readl(cm->common.base + cm->common.reg);
+	reg &= ~GENMASK(cm->mult.width + cm->mult.shift - 1, cm->mult.shift);
+
+	writel(reg | ((n - 1) << cm->mult.shift),
+	       cm->common.base + cm->common.reg);
+
+	spin_unlock_irqrestore(cm->common.lock, flags);
+
+	return 0;
+}
+
+static u8 ccu_mult_get_parent(struct clk_hw *hw)
+{
+	struct ccu_mult *cm = hw_to_ccu_mult(hw);
+
+	return ccu_mux_helper_get_parent(&cm->common, &cm->mux);
+}
+
+static int ccu_mult_set_parent(struct clk_hw *hw, u8 index)
+{
+	struct ccu_mult *cm = hw_to_ccu_mult(hw);
+
+	return ccu_mux_helper_set_parent(&cm->common, &cm->mux, index);
+}
+
+const struct clk_ops ccu_mult_ops = {
+	.disable	= ccu_mult_disable,
+	.enable		= ccu_mult_enable,
+	.is_enabled	= ccu_mult_is_enabled,
+
+	.get_parent	= ccu_mult_get_parent,
+	.set_parent	= ccu_mult_set_parent,
+
+	.determine_rate	= ccu_mult_determine_rate,
+	.recalc_rate	= ccu_mult_recalc_rate,
+	.set_rate	= ccu_mult_set_rate,
+};