1 files changed, 285 insertions, 0 deletions
diff --git a/drivers/clk/imx/clk-composite-8m.c b/drivers/clk/imx/clk-composite-8m.c
new file mode 100644
index 0000000000..27a08c50ac
--- /dev/null
+++ b/drivers/clk/imx/clk-composite-8m.c
@@ -0,0 +1,285 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2018 NXP
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/errno.h>
+#include <linux/export.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+
+#include "clk.h"
+
+#define PCG_PREDIV_SHIFT	16
+#define PCG_PREDIV_WIDTH	3
+#define PCG_PREDIV_MAX		8
+
+#define PCG_DIV_SHIFT		0
+#define PCG_CORE_DIV_WIDTH	3
+#define PCG_DIV_WIDTH		6
+#define PCG_DIV_MAX		64
+
+#define PCG_PCS_SHIFT		24
+#define PCG_PCS_MASK		0x7
+
+#define PCG_CGC_SHIFT		28
+
+static unsigned long imx8m_clk_composite_divider_recalc_rate(struct clk_hw *hw,
+						unsigned long parent_rate)
+{
+	struct clk_divider *divider = to_clk_divider(hw);
+	unsigned long prediv_rate;
+	unsigned int prediv_value;
+	unsigned int div_value;
+
+	prediv_value = readl(divider->reg) >> divider->shift;
+	prediv_value &= clk_div_mask(divider->width);
+
+	prediv_rate = divider_recalc_rate(hw, parent_rate, prediv_value,
+						NULL, divider->flags,
+						divider->width);
+
+	div_value = readl(divider->reg) >> PCG_DIV_SHIFT;
+	div_value &= clk_div_mask(PCG_DIV_WIDTH);
+
+	return divider_recalc_rate(hw, prediv_rate, div_value, NULL,
+				   divider->flags, PCG_DIV_WIDTH);
+}
+
+static int imx8m_clk_composite_compute_dividers(unsigned long rate,
+						unsigned long parent_rate,
+						int *prediv, int *postdiv)
+{
+	int div1, div2;
+	int error = INT_MAX;
+	int ret = -EINVAL;
+
+	*prediv = 1;
+	*postdiv = 1;
+
+	for (div1 = 1; div1 <= PCG_PREDIV_MAX; div1++) {
+		for (div2 = 1; div2 <= PCG_DIV_MAX; div2++) {
+			int new_error = ((parent_rate / div1) / div2) - rate;
+
+			if (abs(new_error) < abs(error)) {
+				*prediv = div1;
+				*postdiv = div2;
+				error = new_error;
+				ret = 0;
+			}
+		}
+	}
+	return ret;
+}
+
+static long imx8m_clk_composite_divider_round_rate(struct clk_hw *hw,
+						unsigned long rate,
+						unsigned long *prate)
+{
+	int prediv_value;
+	int div_value;
+
+	imx8m_clk_composite_compute_dividers(rate, *prate,
+						&prediv_value, &div_value);
+	rate = DIV_ROUND_UP(*prate, prediv_value);
+
+	return DIV_ROUND_UP(rate, div_value);
+
+}
+
+static int imx8m_clk_composite_divider_set_rate(struct clk_hw *hw,
+					unsigned long rate,
+					unsigned long parent_rate)
+{
+	struct clk_divider *divider = to_clk_divider(hw);
+	unsigned long flags;
+	int prediv_value;
+	int div_value;
+	int ret;
+	u32 orig, val;
+
+	ret = imx8m_clk_composite_compute_dividers(rate, parent_rate,
+						&prediv_value, &div_value);
+	if (ret)
+		return -EINVAL;
+
+	spin_lock_irqsave(divider->lock, flags);
+
+	orig = readl(divider->reg);
+	val = orig & ~((clk_div_mask(divider->width) << divider->shift) |
+		       (clk_div_mask(PCG_DIV_WIDTH) << PCG_DIV_SHIFT));
+
+	val |= (u32)(prediv_value  - 1) << divider->shift;
+	val |= (u32)(div_value - 1) << PCG_DIV_SHIFT;
+
+	if (val != orig)
+		writel(val, divider->reg);
+
+	spin_unlock_irqrestore(divider->lock, flags);
+
+	return ret;
+}
+
+static int imx8m_divider_determine_rate(struct clk_hw *hw,
+				      struct clk_rate_request *req)
+{
+	struct clk_divider *divider = to_clk_divider(hw);
+	int prediv_value;
+	int div_value;
+
+	/* if read only, just return current value */
+	if (divider->flags & CLK_DIVIDER_READ_ONLY) {
+		u32 val;
+
+		val = readl(divider->reg);
+		prediv_value = val >> divider->shift;
+		prediv_value &= clk_div_mask(divider->width);
+		prediv_value++;
+
+		div_value = val >> PCG_DIV_SHIFT;
+		div_value &= clk_div_mask(PCG_DIV_WIDTH);
+		div_value++;
+
+		return divider_ro_determine_rate(hw, req, divider->table,
+						 PCG_PREDIV_WIDTH + PCG_DIV_WIDTH,
+						 divider->flags, prediv_value * div_value);
+	}
+
+	return divider_determine_rate(hw, req, divider->table,
+				      PCG_PREDIV_WIDTH + PCG_DIV_WIDTH,
+				      divider->flags);
+}
+
+static const struct clk_ops imx8m_clk_composite_divider_ops = {
+	.recalc_rate = imx8m_clk_composite_divider_recalc_rate,
+	.round_rate = imx8m_clk_composite_divider_round_rate,
+	.set_rate = imx8m_clk_composite_divider_set_rate,
+	.determine_rate = imx8m_divider_determine_rate,
+};
+
+static u8 imx8m_clk_composite_mux_get_parent(struct clk_hw *hw)
+{
+	return clk_mux_ops.get_parent(hw);
+}
+
+static int imx8m_clk_composite_mux_set_parent(struct clk_hw *hw, u8 index)
+{
+	struct clk_mux *mux = to_clk_mux(hw);
+	u32 val = clk_mux_index_to_val(mux->table, mux->flags, index);
+	unsigned long flags = 0;
+	u32 reg;
+
+	if (mux->lock)
+		spin_lock_irqsave(mux->lock, flags);
+
+	reg = readl(mux->reg);
+	reg &= ~(mux->mask << mux->shift);
+	val = val << mux->shift;
+	reg |= val;
+	/*
+	 * write twice to make sure non-target interface
+	 * SEL_A/B point the same clk input.
+	 */
+	writel(reg, mux->reg);
+	writel(reg, mux->reg);
+
+	if (mux->lock)
+		spin_unlock_irqrestore(mux->lock, flags);
+
+	return 0;
+}
+
+static int
+imx8m_clk_composite_mux_determine_rate(struct clk_hw *hw,
+				       struct clk_rate_request *req)
+{
+	return clk_mux_ops.determine_rate(hw, req);
+}
+
+
+static const struct clk_ops imx8m_clk_composite_mux_ops = {
+	.get_parent = imx8m_clk_composite_mux_get_parent,
+	.set_parent = imx8m_clk_composite_mux_set_parent,
+	.determine_rate = imx8m_clk_composite_mux_determine_rate,
+};
+
+struct clk_hw *__imx8m_clk_hw_composite(const char *name,
+					const char * const *parent_names,
+					int num_parents, void __iomem *reg,
+					u32 composite_flags,
+					unsigned long flags)
+{
+	struct clk_hw *hw = ERR_PTR(-ENOMEM), *mux_hw;
+	struct clk_hw *div_hw, *gate_hw = NULL;
+	struct clk_divider *div = NULL;
+	struct clk_gate *gate = NULL;
+	struct clk_mux *mux = NULL;
+	const struct clk_ops *divider_ops;
+	const struct clk_ops *mux_ops;
+
+	mux = kzalloc(sizeof(*mux), GFP_KERNEL);
+	if (!mux)
+		goto fail;
+
+	mux_hw = &mux->hw;
+	mux->reg = reg;
+	mux->shift = PCG_PCS_SHIFT;
+	mux->mask = PCG_PCS_MASK;
+	mux->lock = &imx_ccm_lock;
+
+	div = kzalloc(sizeof(*div), GFP_KERNEL);
+	if (!div)
+		goto fail;
+
+	div_hw = &div->hw;
+	div->reg = reg;
+	if (composite_flags & IMX_COMPOSITE_CORE) {
+		div->shift = PCG_DIV_SHIFT;
+		div->width = PCG_CORE_DIV_WIDTH;
+		divider_ops = &clk_divider_ops;
+		mux_ops = &imx8m_clk_composite_mux_ops;
+	} else if (composite_flags & IMX_COMPOSITE_BUS) {
+		div->shift = PCG_PREDIV_SHIFT;
+		div->width = PCG_PREDIV_WIDTH;
+		divider_ops = &imx8m_clk_composite_divider_ops;
+		mux_ops = &imx8m_clk_composite_mux_ops;
+	} else {
+		div->shift = PCG_PREDIV_SHIFT;
+		div->width = PCG_PREDIV_WIDTH;
+		divider_ops = &imx8m_clk_composite_divider_ops;
+		mux_ops = &clk_mux_ops;
+		if (!(composite_flags & IMX_COMPOSITE_FW_MANAGED))
+			flags |= CLK_SET_PARENT_GATE;
+	}
+
+	div->lock = &imx_ccm_lock;
+	div->flags = CLK_DIVIDER_ROUND_CLOSEST;
+
+	/* skip registering the gate ops if M4 is enabled */
+	if (!mcore_booted) {
+		gate = kzalloc(sizeof(*gate), GFP_KERNEL);
+		if (!gate)
+			goto fail;
+
+		gate_hw = &gate->hw;
+		gate->reg = reg;
+		gate->bit_idx = PCG_CGC_SHIFT;
+		gate->lock = &imx_ccm_lock;
+	}
+
+	hw = clk_hw_register_composite(NULL, name, parent_names, num_parents,
+			mux_hw, mux_ops, div_hw,
+			divider_ops, gate_hw, &clk_gate_ops, flags);
+	if (IS_ERR(hw))
+		goto fail;
+
+	return hw;
+
+fail:
+	kfree(gate);
+	kfree(div);
+	kfree(mux);
+	return ERR_CAST(hw);
+}
+EXPORT_SYMBOL_GPL(__imx8m_clk_hw_composite);