1 files changed, 236 insertions, 0 deletions
diff --git a/drivers/clk/sunxi-ng/ccu_nm.c b/drivers/clk/sunxi-ng/ccu_nm.c
new file mode 100644
index 000000000..9e3944f86
--- /dev/null
+++ b/drivers/clk/sunxi-ng/ccu_nm.c
@@ -0,0 +1,236 @@
+/*
+ * 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_frac.h"
+#include "ccu_gate.h"
+#include "ccu_nm.h"
+
+struct _ccu_nm {
+	unsigned long	n, min_n, max_n;
+	unsigned long	m, min_m, max_m;
+};
+
+static unsigned long ccu_nm_calc_rate(unsigned long parent,
+				      unsigned long n, unsigned long m)
+{
+	u64 rate = parent;
+
+	rate *= n;
+	do_div(rate, m);
+
+	return rate;
+}
+
+static void ccu_nm_find_best(unsigned long parent, unsigned long rate,
+			     struct _ccu_nm *nm)
+{
+	unsigned long best_rate = 0;
+	unsigned long best_n = 0, best_m = 0;
+	unsigned long _n, _m;
+
+	for (_n = nm->min_n; _n <= nm->max_n; _n++) {
+		for (_m = nm->min_m; _m <= nm->max_m; _m++) {
+			unsigned long tmp_rate = ccu_nm_calc_rate(parent,
+								  _n, _m);
+
+			if (tmp_rate > rate)
+				continue;
+
+			if ((rate - tmp_rate) < (rate - best_rate)) {
+				best_rate = tmp_rate;
+				best_n = _n;
+				best_m = _m;
+			}
+		}
+	}
+
+	nm->n = best_n;
+	nm->m = best_m;
+}
+
+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 rate;
+	unsigned long n, m;
+	u32 reg;
+
+	if (ccu_frac_helper_is_enabled(&nm->common, &nm->frac)) {
+		rate = ccu_frac_helper_read_rate(&nm->common, &nm->frac);
+
+		if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV)
+			rate /= nm->fixed_post_div;
+
+		return rate;
+	}
+
+	reg = readl(nm->common.base + nm->common.reg);
+
+	n = reg >> nm->n.shift;
+	n &= (1 << nm->n.width) - 1;
+	n += nm->n.offset;
+	if (!n)
+		n++;
+
+	m = reg >> nm->m.shift;
+	m &= (1 << nm->m.width) - 1;
+	m += nm->m.offset;
+	if (!m)
+		m++;
+
+	if (ccu_sdm_helper_is_enabled(&nm->common, &nm->sdm))
+		rate = ccu_sdm_helper_read_rate(&nm->common, &nm->sdm, m, n);
+	else
+		rate = ccu_nm_calc_rate(parent_rate, n, m);
+
+	if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV)
+		rate /= nm->fixed_post_div;
+
+	return rate;
+}
+
+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);
+	struct _ccu_nm _nm;
+
+	if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV)
+		rate *= nm->fixed_post_div;
+
+	if (rate < nm->min_rate) {
+		rate = nm->min_rate;
+		if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV)
+			rate /= nm->fixed_post_div;
+		return rate;
+	}
+
+	if (ccu_frac_helper_has_rate(&nm->common, &nm->frac, rate)) {
+		if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV)
+			rate /= nm->fixed_post_div;
+		return rate;
+	}
+
+	if (ccu_sdm_helper_has_rate(&nm->common, &nm->sdm, rate)) {
+		if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV)
+			rate /= nm->fixed_post_div;
+		return rate;
+	}
+
+	_nm.min_n = nm->n.min ?: 1;
+	_nm.max_n = nm->n.max ?: 1 << nm->n.width;
+	_nm.min_m = 1;
+	_nm.max_m = nm->m.max ?: 1 << nm->m.width;
+
+	ccu_nm_find_best(*parent_rate, rate, &_nm);
+	rate = ccu_nm_calc_rate(*parent_rate, _nm.n, _nm.m);
+
+	if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV)
+		rate /= nm->fixed_post_div;
+
+	return rate;
+}
+
+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);
+	struct _ccu_nm _nm;
+	unsigned long flags;
+	u32 reg;
+
+	/* Adjust target rate according to post-dividers */
+	if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV)
+		rate = rate * nm->fixed_post_div;
+
+	if (ccu_frac_helper_has_rate(&nm->common, &nm->frac, rate)) {
+		spin_lock_irqsave(nm->common.lock, flags);
+
+		/* most SoCs require M to be 0 if fractional mode is used */
+		reg = readl(nm->common.base + nm->common.reg);
+		reg &= ~GENMASK(nm->m.width + nm->m.shift - 1, nm->m.shift);
+		writel(reg, nm->common.base + nm->common.reg);
+
+		spin_unlock_irqrestore(nm->common.lock, flags);
+
+		ccu_frac_helper_enable(&nm->common, &nm->frac);
+
+		return ccu_frac_helper_set_rate(&nm->common, &nm->frac,
+						rate, nm->lock);
+	} else {
+		ccu_frac_helper_disable(&nm->common, &nm->frac);
+	}
+
+	_nm.min_n = nm->n.min ?: 1;
+	_nm.max_n = nm->n.max ?: 1 << nm->n.width;
+	_nm.min_m = 1;
+	_nm.max_m = nm->m.max ?: 1 << nm->m.width;
+
+	if (ccu_sdm_helper_has_rate(&nm->common, &nm->sdm, rate)) {
+		ccu_sdm_helper_enable(&nm->common, &nm->sdm, rate);
+
+		/* Sigma delta modulation requires specific N and M factors */
+		ccu_sdm_helper_get_factors(&nm->common, &nm->sdm, rate,
+					   &_nm.m, &_nm.n);
+	} else {
+		ccu_sdm_helper_disable(&nm->common, &nm->sdm);
+		ccu_nm_find_best(parent_rate, rate, &_nm);
+	}
+
+	spin_lock_irqsave(nm->common.lock, flags);
+
+	reg = readl(nm->common.base + nm->common.reg);
+	reg &= ~GENMASK(nm->n.width + nm->n.shift - 1, nm->n.shift);
+	reg &= ~GENMASK(nm->m.width + nm->m.shift - 1, nm->m.shift);
+
+	reg |= (_nm.n - nm->n.offset) << nm->n.shift;
+	reg |= (_nm.m - nm->m.offset) << nm->m.shift;
+	writel(reg, 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,
+};