From 3a947321d72af191ee87a390295c661c876cc6f4 Mon Sep 17 00:00:00 2001
From: John Crispin <blogic@openwrt.org>
Date: Thu, 31 Mar 2016 02:26:37 +0200
Subject: [PATCH 14/57] clk: mediatek: Export CPU mux clocks for CPU frequency
 control

This patch adds CPU mux clocks which are used by Mediatek cpufreq driver
for intermediate clock source switching.

Signed-off-by: Pi-Cheng Chen <pi-cheng.chen@linaro.org>
---
 drivers/clk/mediatek/Makefile          |   2 +-
 drivers/clk/mediatek/clk-cpumux.c      | 127 +++++++++++++++++++++++++++++++++
 drivers/clk/mediatek/clk-cpumux.h      |  22 ++++++
 drivers/clk/mediatek/clk-mt2701.c      |   8 +++
 drivers/clk/mediatek/clk-mt8173.c      |  23 ++++++
 include/dt-bindings/clock/mt2701-clk.h |   3 +-
 include/dt-bindings/clock/mt8173-clk.h |   4 +-
 7 files changed, 186 insertions(+), 3 deletions(-)
 create mode 100644 drivers/clk/mediatek/clk-cpumux.c
 create mode 100644 drivers/clk/mediatek/clk-cpumux.h

--- a/drivers/clk/mediatek/Makefile
+++ b/drivers/clk/mediatek/Makefile
@@ -1,4 +1,4 @@
-obj-$(CONFIG_COMMON_CLK_MEDIATEK) += clk-mtk.o clk-pll.o clk-gate.o clk-apmixed.o
+obj-$(CONFIG_COMMON_CLK_MEDIATEK) += clk-mtk.o clk-pll.o clk-gate.o clk-apmixed.o clk-cpumux.o
 obj-$(CONFIG_RESET_CONTROLLER) += reset.o
 obj-$(CONFIG_COMMON_CLK_MT2701) += clk-mt2701.o
 obj-$(CONFIG_COMMON_CLK_MT8135) += clk-mt8135.o
--- /dev/null
+++ b/drivers/clk/mediatek/clk-cpumux.c
@@ -0,0 +1,127 @@
+/*
+ * Copyright (c) 2015 Linaro Ltd.
+ * Author: Pi-Cheng Chen <pi-cheng.chen@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/mfd/syscon.h>
+#include <linux/slab.h>
+
+#include "clk-mtk.h"
+#include "clk-cpumux.h"
+
+struct mtk_clk_cpumux {
+	struct clk_hw	hw;
+	struct regmap	*regmap;
+	u32		reg;
+	u32		mask;
+	u8		shift;
+};
+
+static inline struct mtk_clk_cpumux *to_mtk_clk_mux(struct clk_hw *_hw)
+{
+	return container_of(_hw, struct mtk_clk_cpumux, hw);
+}
+
+static u8 clk_cpumux_get_parent(struct clk_hw *hw)
+{
+	struct mtk_clk_cpumux *mux = to_mtk_clk_mux(hw);
+	int num_parents = clk_hw_get_num_parents(hw);
+	unsigned int val;
+
+	regmap_read(mux->regmap, mux->reg, &val);
+
+	val >>= mux->shift;
+	val &= mux->mask;
+
+	if (val >= num_parents)
+		return -EINVAL;
+
+	return val;
+}
+
+static int clk_cpumux_set_parent(struct clk_hw *hw, u8 index)
+{
+	struct mtk_clk_cpumux *mux = to_mtk_clk_mux(hw);
+	u32 mask, val;
+
+	val = index << mux->shift;
+	mask = mux->mask << mux->shift;
+
+	return regmap_update_bits(mux->regmap, mux->reg, mask, val);
+}
+
+static const struct clk_ops clk_cpumux_ops = {
+	.get_parent = clk_cpumux_get_parent,
+	.set_parent = clk_cpumux_set_parent,
+};
+
+static struct clk __init *mtk_clk_register_cpumux(const struct mtk_composite *mux,
+					   struct regmap *regmap)
+{
+	struct mtk_clk_cpumux *cpumux;
+	struct clk *clk;
+	struct clk_init_data init;
+
+	cpumux = kzalloc(sizeof(*cpumux), GFP_KERNEL);
+	if (!cpumux)
+		return ERR_PTR(-ENOMEM);
+
+	init.name = mux->name;
+	init.ops = &clk_cpumux_ops;
+	init.parent_names = mux->parent_names;
+	init.num_parents = mux->num_parents;
+	init.flags = mux->flags;
+
+	cpumux->reg = mux->mux_reg;
+	cpumux->shift = mux->mux_shift;
+	cpumux->mask = BIT(mux->mux_width) - 1;
+	cpumux->regmap = regmap;
+	cpumux->hw.init = &init;
+
+	clk = clk_register(NULL, &cpumux->hw);
+	if (IS_ERR(clk))
+		kfree(cpumux);
+
+	return clk;
+}
+
+int __init mtk_clk_register_cpumuxes(struct device_node *node,
+			      const struct mtk_composite *clks, int num,
+			      struct clk_onecell_data *clk_data)
+{
+	int i;
+	struct clk *clk;
+	struct regmap *regmap;
+
+	regmap = syscon_node_to_regmap(node);
+	if (IS_ERR(regmap)) {
+		pr_err("Cannot find regmap for %s: %ld\n", node->full_name,
+		       PTR_ERR(regmap));
+		return PTR_ERR(regmap);
+	}
+
+	for (i = 0; i < num; i++) {
+		const struct mtk_composite *mux = &clks[i];
+
+		clk = mtk_clk_register_cpumux(mux, regmap);
+		if (IS_ERR(clk)) {
+			pr_err("Failed to register clk %s: %ld\n",
+			       mux->name, PTR_ERR(clk));
+			continue;
+		}
+
+		clk_data->clks[mux->id] = clk;
+	}
+
+	return 0;
+}
--- /dev/null
+++ b/drivers/clk/mediatek/clk-cpumux.h
@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) 2015 Linaro Ltd.
+ * Author: Pi-Cheng Chen <pi-cheng.chen@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __DRV_CLK_CPUMUX_H
+#define __DRV_CLK_CPUMUX_H
+
+int mtk_clk_register_cpumuxes(struct device_node *node,
+			      const struct mtk_composite *clks, int num,
+			      struct clk_onecell_data *clk_data);
+
+#endif /* __DRV_CLK_CPUMUX_H */
--- a/drivers/clk/mediatek/clk-mt2701.c
+++ b/drivers/clk/mediatek/clk-mt2701.c
@@ -18,6 +18,7 @@
 
 #include "clk-mtk.h"
 #include "clk-gate.h"
+#include "clk-cpumux.h"
 
 #include <dt-bindings/clock/mt2701-clk.h>
 
@@ -465,6 +466,10 @@ static const char * const cpu_parents[]
 	"mmpll"
 };
 
+static const struct mtk_composite cpu_muxes[] __initconst = {
+	MUX(CLK_INFRA_CPUSEL, "infra_cpu_sel", cpu_parents, 0x0000, 2, 2),
+};
+
 static const struct mtk_composite top_muxes[] __initconst = {
 	MUX_GATE(CLK_TOP_AXI_SEL, "axi_sel", axi_parents,
 		0x0040, 0, 3, INVALID_MUX_GATE_BIT),
@@ -677,6 +682,9 @@ static void __init mtk_infrasys_init(str
 	mtk_clk_register_factors(infra_fixed_divs, ARRAY_SIZE(infra_fixed_divs),
 						clk_data);
 
+	mtk_clk_register_cpumuxes(node, cpu_muxes, ARRAY_SIZE(cpu_muxes),
+						clk_data);
+
 	r = of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
 	if (r)
 		pr_err("%s(): could not register clock provider: %d\n",
--- a/drivers/clk/mediatek/clk-mt8173.c
+++ b/drivers/clk/mediatek/clk-mt8173.c
@@ -18,6 +18,7 @@
 
 #include "clk-mtk.h"
 #include "clk-gate.h"
+#include "clk-cpumux.h"
 
 #include <dt-bindings/clock/mt8173-clk.h>
 
@@ -525,6 +526,25 @@ static const char * const i2s3_b_ck_pare
 	"apll2_div5"
 };
 
+static const char * const ca53_parents[] __initconst = {
+	"clk26m",
+	"armca7pll",
+	"mainpll",
+	"univpll"
+};
+
+static const char * const ca57_parents[] __initconst = {
+	"clk26m",
+	"armca15pll",
+	"mainpll",
+	"univpll"
+};
+
+static const struct mtk_composite cpu_muxes[] __initconst = {
+	MUX(CLK_INFRA_CA53SEL, "infra_ca53_sel", ca53_parents, 0x0000, 0, 2),
+	MUX(CLK_INFRA_CA57SEL, "infra_ca57_sel", ca57_parents, 0x0000, 2, 2),
+};
+
 static const struct mtk_composite top_muxes[] __initconst = {
 	/* CLK_CFG_0 */
 	MUX(CLK_TOP_AXI_SEL, "axi_sel", axi_parents, 0x0040, 0, 3),
@@ -948,6 +968,9 @@ static void __init mtk_infrasys_init(str
 						clk_data);
 	mtk_clk_register_factors(infra_divs, ARRAY_SIZE(infra_divs), clk_data);
 
+	mtk_clk_register_cpumuxes(node, cpu_muxes, ARRAY_SIZE(cpu_muxes),
+						clk_data);
+
 	r = of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
 	if (r)
 		pr_err("%s(): could not register clock provider: %d\n",
--- a/include/dt-bindings/clock/mt2701-clk.h
+++ b/include/dt-bindings/clock/mt2701-clk.h
@@ -221,7 +221,8 @@
 #define CLK_INFRA_PMICWRAP			17
 #define CLK_INFRA_DDCCI				18
 #define CLK_INFRA_CLK_13M			19
-#define CLK_INFRA_NR				20
+#define CLK_INFRA_CPUSEL			20
+#define CLK_INFRA_NR				21
 
 /* PERICFG */
 
--- a/include/dt-bindings/clock/mt8173-clk.h
+++ b/include/dt-bindings/clock/mt8173-clk.h
@@ -193,7 +193,9 @@
 #define CLK_INFRA_PMICSPI		10
 #define CLK_INFRA_PMICWRAP		11
 #define CLK_INFRA_CLK_13M		12
-#define CLK_INFRA_NR_CLK		13
+#define CLK_INFRA_CA53SEL		13
+#define CLK_INFRA_CA57SEL		14
+#define CLK_INFRA_NR_CLK		15
 
 /* PERI_SYS */