1 files changed, 329 insertions, 0 deletions
diff --git a/drivers/clk/sunxi-ng/ccu_mp.c b/drivers/clk/sunxi-ng/ccu_mp.c
new file mode 100644
index 000000000..57cf2d615
--- /dev/null
+++ b/drivers/clk/sunxi-ng/ccu_mp.c
@@ -0,0 +1,329 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2016 Maxime Ripard
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/io.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 = 1; _p <= max_p; _p <<= 1) {
+		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_find_best_with_parent_adj(struct clk_hw *hw,
+						      unsigned long *parent,
+						      unsigned long rate,
+						      unsigned int max_m,
+						      unsigned int max_p)
+{
+	unsigned long parent_rate_saved;
+	unsigned long parent_rate, now;
+	unsigned long best_rate = 0;
+	unsigned int _m, _p, div;
+	unsigned long maxdiv;
+
+	parent_rate_saved = *parent;
+
+	/*
+	 * The maximum divider we can use without overflowing
+	 * unsigned long in rate * m * p below
+	 */
+	maxdiv = max_m * max_p;
+	maxdiv = min(ULONG_MAX / rate, maxdiv);
+
+	for (_p = 1; _p <= max_p; _p <<= 1) {
+		for (_m = 1; _m <= max_m; _m++) {
+			div = _m * _p;
+
+			if (div > maxdiv)
+				break;
+
+			if (rate * div == parent_rate_saved) {
+				/*
+				 * It's the most ideal case if the requested
+				 * rate can be divided from parent clock without
+				 * needing to change parent rate, so return the
+				 * divider immediately.
+				 */
+				*parent = parent_rate_saved;
+				return rate;
+			}
+
+			parent_rate = clk_hw_round_rate(hw, rate * div);
+			now = parent_rate / div;
+
+			if (now <= rate && now > best_rate) {
+				best_rate = now;
+				*parent = parent_rate;
+
+				if (now == rate)
+					return rate;
+			}
+		}
+	}
+
+	return best_rate;
+}
+
+static unsigned long ccu_mp_round_rate(struct ccu_mux_internal *mux,
+				       struct clk_hw *hw,
+				       unsigned long *parent_rate,
+				       unsigned long rate,
+				       void *data)
+{
+	struct ccu_mp *cmp = data;
+	unsigned int max_m, max_p;
+	unsigned int m, p;
+
+	if (cmp->common.features & CCU_FEATURE_FIXED_POSTDIV)
+		rate *= cmp->fixed_post_div;
+
+	max_m = cmp->m.max ?: 1 << cmp->m.width;
+	max_p = cmp->p.max ?: 1 << ((1 << cmp->p.width) - 1);
+
+	if (!clk_hw_can_set_rate_parent(&cmp->common.hw)) {
+		ccu_mp_find_best(*parent_rate, rate, max_m, max_p, &m, &p);
+		rate = *parent_rate / p / m;
+	} else {
+		rate = ccu_mp_find_best_with_parent_adj(hw, parent_rate, rate,
+							max_m, max_p);
+	}
+
+	if (cmp->common.features & CCU_FEATURE_FIXED_POSTDIV)
+		rate /= cmp->fixed_post_div;
+
+	return rate;
+}
+
+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 long rate;
+	unsigned int m, p;
+	u32 reg;
+
+	/* Adjust parent_rate according to pre-dividers */
+	parent_rate = ccu_mux_helper_apply_prediv(&cmp->common, &cmp->mux, -1,
+						  parent_rate);
+
+	reg = readl(cmp->common.base + cmp->common.reg);
+
+	m = reg >> cmp->m.shift;
+	m &= (1 << cmp->m.width) - 1;
+	m += cmp->m.offset;
+	if (!m)
+		m++;
+
+	p = reg >> cmp->p.shift;
+	p &= (1 << cmp->p.width) - 1;
+
+	rate = (parent_rate >> p) / m;
+	if (cmp->common.features & CCU_FEATURE_FIXED_POSTDIV)
+		rate /= cmp->fixed_post_div;
+
+	return rate;
+}
+
+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 max_m, max_p;
+	unsigned int m, p;
+	u32 reg;
+
+	/* Adjust parent_rate according to pre-dividers */
+	parent_rate = ccu_mux_helper_apply_prediv(&cmp->common, &cmp->mux, -1,
+						  parent_rate);
+
+	max_m = cmp->m.max ?: 1 << cmp->m.width;
+	max_p = cmp->p.max ?: 1 << ((1 << cmp->p.width) - 1);
+
+	/* Adjust target rate according to post-dividers */
+	if (cmp->common.features & CCU_FEATURE_FIXED_POSTDIV)
+		rate = rate * cmp->fixed_post_div;
+
+	ccu_mp_find_best(parent_rate, rate, max_m, max_p, &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);
+	reg |= (m - cmp->m.offset) << cmp->m.shift;
+	reg |= ilog2(p) << cmp->p.shift;
+
+	writel(reg, 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,
+};
+EXPORT_SYMBOL_NS_GPL(ccu_mp_ops, SUNXI_CCU);
+
+/*
+ * Support for MMC timing mode switching
+ *
+ * The MMC clocks on some SoCs support switching between old and
+ * new timing modes. A platform specific API is provided to query
+ * and set the timing mode on supported SoCs.
+ *
+ * In addition, a special class of ccu_mp_ops is provided, which
+ * takes in to account the timing mode switch. When the new timing
+ * mode is active, the clock output rate is halved. This new class
+ * is a wrapper around the generic ccu_mp_ops. When clock rates
+ * are passed through to ccu_mp_ops callbacks, they are doubled
+ * if the new timing mode bit is set, to account for the post
+ * divider. Conversely, when clock rates are passed back, they
+ * are halved if the mode bit is set.
+ */
+
+static unsigned long ccu_mp_mmc_recalc_rate(struct clk_hw *hw,
+					    unsigned long parent_rate)
+{
+	unsigned long rate = ccu_mp_recalc_rate(hw, parent_rate);
+	struct ccu_common *cm = hw_to_ccu_common(hw);
+	u32 val = readl(cm->base + cm->reg);
+
+	if (val & CCU_MMC_NEW_TIMING_MODE)
+		return rate / 2;
+	return rate;
+}
+
+static int ccu_mp_mmc_determine_rate(struct clk_hw *hw,
+				     struct clk_rate_request *req)
+{
+	struct ccu_common *cm = hw_to_ccu_common(hw);
+	u32 val = readl(cm->base + cm->reg);
+	int ret;
+
+	/* adjust the requested clock rate */
+	if (val & CCU_MMC_NEW_TIMING_MODE) {
+		req->rate *= 2;
+		req->min_rate *= 2;
+		req->max_rate *= 2;
+	}
+
+	ret = ccu_mp_determine_rate(hw, req);
+
+	/* re-adjust the requested clock rate back */
+	if (val & CCU_MMC_NEW_TIMING_MODE) {
+		req->rate /= 2;
+		req->min_rate /= 2;
+		req->max_rate /= 2;
+	}
+
+	return ret;
+}
+
+static int ccu_mp_mmc_set_rate(struct clk_hw *hw, unsigned long rate,
+			       unsigned long parent_rate)
+{
+	struct ccu_common *cm = hw_to_ccu_common(hw);
+	u32 val = readl(cm->base + cm->reg);
+
+	if (val & CCU_MMC_NEW_TIMING_MODE)
+		rate *= 2;
+
+	return ccu_mp_set_rate(hw, rate, parent_rate);
+}
+
+const struct clk_ops ccu_mp_mmc_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_mmc_determine_rate,
+	.recalc_rate	= ccu_mp_mmc_recalc_rate,
+	.set_rate	= ccu_mp_mmc_set_rate,
+};
+EXPORT_SYMBOL_NS_GPL(ccu_mp_mmc_ops, SUNXI_CCU);