1 files changed, 178 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 000000000000..6d9d3714b4df
--- /dev/null
+++ b/drivers/clk/imx/clk-composite-8m.c
@@ -0,0 +1,178 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2018 NXP
+ */
+
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/clk-provider.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_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 = 0;
+	int prediv_value;
+	int div_value;
+	int ret = 0;
+	u32 val;
+
+	ret = imx8m_clk_composite_compute_dividers(rate, parent_rate,
+						&prediv_value, &div_value);
+	if (ret)
+		return -EINVAL;
+
+	spin_lock_irqsave(divider->lock, flags);
+
+	val = readl(divider->reg);
+	val &= ~((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;
+	writel(val, divider->reg);
+
+	spin_unlock_irqrestore(divider->lock, flags);
+
+	return ret;
+}
+
+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,
+};
+
+struct clk *imx8m_clk_composite_flags(const char *name,
+					const char **parent_names,
+					int num_parents, void __iomem *reg,
+					unsigned long flags)
+{
+	struct clk_hw *hw = ERR_PTR(-ENOMEM), *mux_hw;
+	struct clk_hw *div_hw, *gate_hw;
+	struct clk_divider *div = NULL;
+	struct clk_gate *gate = NULL;
+	struct clk_mux *mux = NULL;
+
+	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;
+
+	div = kzalloc(sizeof(*div), GFP_KERNEL);
+	if (!div)
+		goto fail;
+
+	div_hw = &div->hw;
+	div->reg = reg;
+	div->shift = PCG_PREDIV_SHIFT;
+	div->width = PCG_PREDIV_WIDTH;
+	div->lock = &imx_ccm_lock;
+	div->flags = CLK_DIVIDER_ROUND_CLOSEST;
+
+	gate = kzalloc(sizeof(*gate), GFP_KERNEL);
+	if (!gate)
+		goto fail;
+
+	gate_hw = &gate->hw;
+	gate->reg = reg;
+	gate->bit_idx = PCG_CGC_SHIFT;
+
+	hw = clk_hw_register_composite(NULL, name, parent_names, num_parents,
+			mux_hw, &clk_mux_ops, div_hw,
+			&imx8m_clk_composite_divider_ops,
+			gate_hw, &clk_gate_ops, flags);
+	if (IS_ERR(hw))
+		goto fail;
+
+	return hw->clk;
+
+fail:
+	kfree(gate);
+	kfree(div);
+	kfree(mux);
+	return ERR_CAST(hw);
+}