[PATCH 1/3] clk: arm: sunxi: Add a new clock driver for sunxi SOCs

Emilio López emilio at elopez.com.ar
Tue Jan 22 01:12:54 EST 2013


This commit implements the base CPU clocks for sunxi devices. It has
been tested using a slightly modified cpufreq driver from the
linux-sunxi 3.0 tree.

Additionally, document the new bindings introduced by this patch, and drop
the (now unused) old sunxi clock driver.

Idling:
    / # find /sys/kernel/debug/clk -name clk_rate -print -exec cat {} \;
    /sys/kernel/debug/clk/osc24M/pll1/cpu/axi/ahb/apb0/clk_rate
    30000000
    /sys/kernel/debug/clk/osc24M/pll1/cpu/axi/ahb/clk_rate
    60000000
    /sys/kernel/debug/clk/osc24M/pll1/cpu/axi/clk_rate
    60000000
    /sys/kernel/debug/clk/osc24M/pll1/cpu/clk_rate
    60000000
    /sys/kernel/debug/clk/osc24M/pll1/clk_rate
    60000000
    /sys/kernel/debug/clk/osc24M/clk_rate
    24000000
    /sys/kernel/debug/clk/osc32k/clk_rate
    32768

After "yes >/dev/null &":
    / # find /sys/kernel/debug/clk -name clk_rate -print -exec cat {} \;
    /sys/kernel/debug/clk/osc24M/pll1/cpu/axi/ahb/apb0/clk_rate
    84000000
    /sys/kernel/debug/clk/osc24M/pll1/cpu/axi/ahb/clk_rate
    168000000
    /sys/kernel/debug/clk/osc24M/pll1/cpu/axi/clk_rate
    336000000
    /sys/kernel/debug/clk/osc24M/pll1/cpu/clk_rate
    1008000000
    /sys/kernel/debug/clk/osc24M/pll1/clk_rate
    1008000000
    /sys/kernel/debug/clk/osc24M/clk_rate
    24000000
    /sys/kernel/debug/clk/osc32k/clk_rate
    32768

Signed-off-by: Emilio López <emilio at elopez.com.ar>
---
 Documentation/devicetree/bindings/clock/sunxi.txt |  47 ++++
 drivers/clk/Makefile                              |   2 +-
 drivers/clk/clk-sunxi.c                           |  30 ---
 drivers/clk/sunxi/Makefile                        |   5 +
 drivers/clk/sunxi/clk-factors.c                   | 175 ++++++++++++++
 drivers/clk/sunxi/clk-factors.h                   |  25 ++
 drivers/clk/sunxi/clk-fixed-gate.c                | 152 +++++++++++++
 drivers/clk/sunxi/clk-fixed-gate.h                |  13 ++
 drivers/clk/sunxi/clk-sunxi.c                     | 265 ++++++++++++++++++++++
 9 files changed, 683 insertions(+), 31 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/clock/sunxi.txt
 delete mode 100644 drivers/clk/clk-sunxi.c
 create mode 100644 drivers/clk/sunxi/Makefile
 create mode 100644 drivers/clk/sunxi/clk-factors.c
 create mode 100644 drivers/clk/sunxi/clk-factors.h
 create mode 100644 drivers/clk/sunxi/clk-fixed-gate.c
 create mode 100644 drivers/clk/sunxi/clk-fixed-gate.h
 create mode 100644 drivers/clk/sunxi/clk-sunxi.c

diff --git a/Documentation/devicetree/bindings/clock/sunxi.txt b/Documentation/devicetree/bindings/clock/sunxi.txt
new file mode 100644
index 0000000..446c5ca
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/sunxi.txt
@@ -0,0 +1,47 @@
+Device Tree Clock bindings for arch-sunxi
+
+This binding uses the common clock binding[1].
+
+[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
+
+Required properties:
+- compatible : shall be one of the following:
+	"allwinner,sunxi-osc-clk" - for a gatable oscillator
+	"allwinner,sunxi-pll1-clk" - for the main PLL clock
+	"allwinner,sunxi-cpu-clk" - for the CPU multiplexer clock
+	"allwinner,sunxi-axi-clk" - for the sunxi AXI clock
+	"allwinner,sunxi-ahb-clk" - for the sunxi AHB clock
+	"allwinner,sunxi-apb0-clk" - for the sunxi APB0 clock
+
+Required properties for all clocks:
+- reg : shall be the control register address for the clock.
+- clocks : shall be the input parent clock(s) phandle for the clock, except for
+	the root gatable oscillator clock where it is not present
+- #clock-cells : from common clock binding; shall be set to 0.
+
+Additionally, the gatable oscillator clock requires:
+- clock-frequency : shall be the frequency of the oscillator.
+
+
+For example:
+
+osc24M: osc24M {
+	#clock-cells = <0>;
+	compatible = "allwinner,sunxi-osc-clk";
+	reg = <0x01c20050 0x4>;
+	clock-frequency = <24000000>;
+};
+
+pll1: pll1 at 01c20000 {
+	#clock-cells = <0>;
+	compatible = "allwinner,sunxi-pll1-clk";
+	reg = <0x01c20000 0x4>;
+	clocks = <&osc24M>;
+};
+
+cpu: cpu at 01c20054 {
+	#clock-cells = <0>;
+	compatible = "allwinner,sunxi-cpu-clk";
+	reg = <0x01c20054 0x4>;
+	clocks = <&osc32k>, <&osc24M>, <&pll1>;
+};
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index ee90e87..129afed 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -20,7 +20,7 @@ endif
 obj-$(CONFIG_MACH_LOONGSON1)	+= clk-ls1x.o
 obj-$(CONFIG_ARCH_U8500)	+= ux500/
 obj-$(CONFIG_ARCH_VT8500)	+= clk-vt8500.o
-obj-$(CONFIG_ARCH_SUNXI)	+= clk-sunxi.o
+obj-$(CONFIG_ARCH_SUNXI)	+= sunxi/
 obj-$(CONFIG_ARCH_ZYNQ)		+= clk-zynq.o
 
 # Chip specific
diff --git a/drivers/clk/clk-sunxi.c b/drivers/clk/clk-sunxi.c
deleted file mode 100644
index 0e831b5..0000000
--- a/drivers/clk/clk-sunxi.c
+++ /dev/null
@@ -1,30 +0,0 @@
-/*
- * Copyright 2012 Maxime Ripard
- *
- * Maxime Ripard <maxime.ripard at 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.
- *
- * 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/clkdev.h>
-#include <linux/clk/sunxi.h>
-#include <linux/of.h>
-
-static const __initconst struct of_device_id clk_match[] = {
-	{ .compatible = "fixed-clock", .data = of_fixed_clk_setup, },
-	{}
-};
-
-void __init sunxi_init_clocks(void)
-{
-	of_clk_init(clk_match);
-}
diff --git a/drivers/clk/sunxi/Makefile b/drivers/clk/sunxi/Makefile
new file mode 100644
index 0000000..8e773be
--- /dev/null
+++ b/drivers/clk/sunxi/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for sunxi specific clk
+#
+
+obj-y += clk-sunxi.o clk-factors.o clk-fixed-gate.o
diff --git a/drivers/clk/sunxi/clk-factors.c b/drivers/clk/sunxi/clk-factors.c
new file mode 100644
index 0000000..428b47d
--- /dev/null
+++ b/drivers/clk/sunxi/clk-factors.c
@@ -0,0 +1,175 @@
+/*
+ * Copyright (C) 2013 Emilio López <emilio at elopez.com.ar>
+ *
+ * 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.
+ *
+ * Adjustable factor-based clock implementation
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/string.h>
+
+#include <linux/delay.h>
+
+#include "clk-factors.h"
+
+/*
+ * DOC: basic adjustable factor-based clock that cannot gate
+ *
+ * Traits of this clock:
+ * prepare - clk_prepare only ensures that parents are prepared
+ * enable - clk_enable only ensures that parents are enabled
+ * rate - rate is adjustable.
+ *        clk->rate = (parent->rate * N * (K + 1) >> P) / (M + 1)
+ * parent - fixed parent.  No clk_set_parent support
+ */
+
+struct clk_factors {
+	struct clk_hw hw;
+	void __iomem *reg;
+	struct clk_factors_config *config;
+	void (*get_factors) (u32 *rate, u8 *n, u8 *k, u8 *m, u8 *p);
+	spinlock_t *lock;
+};
+
+#define to_clk_factors(_hw) container_of(_hw, struct clk_factors, hw)
+
+#define SETMASK(len, pos)		(((-1U) >> (31-len))  << (pos))
+#define CLRMASK(len, pos)		(~(SETMASK(len, pos)))
+#define FACTOR_GET(bit, len, reg)	(((reg) & SETMASK(len, bit)) >> (bit))
+
+#define FACTOR_SET(bit, len, reg, val) \
+	(((reg) & CLRMASK(len, bit)) | (val << (bit)))
+
+static unsigned long clk_factors_recalc_rate(struct clk_hw *hw,
+					     unsigned long parent_rate)
+{
+	u8 n, k, p, m;
+	u32 reg;
+	unsigned long rate;
+	struct clk_factors *factors = to_clk_factors(hw);
+	struct clk_factors_config *config = factors->config;
+
+	/* Fetch the register value */
+	reg = readl(factors->reg);
+
+	/* Get each individual factor */
+	n = FACTOR_GET(config->nshift, config->nwidth, reg);
+	k = FACTOR_GET(config->kshift, config->kwidth, reg);
+	m = FACTOR_GET(config->mshift, config->mwidth, reg);
+	p = FACTOR_GET(config->pshift, config->pwidth, reg);
+
+	/* Calculate the rate */
+	rate = (parent_rate * n * (k + 1) >> p) / (m + 1);
+
+	return rate;
+}
+
+static long clk_factors_round_rate(struct clk_hw *hw, unsigned long rate,
+				   unsigned long *parent_rate)
+{
+	struct clk_factors *factors = to_clk_factors(hw);
+	factors->get_factors((u32 *)&rate, NULL, NULL, NULL, NULL);
+
+	return rate;
+}
+
+static int clk_factors_set_rate(struct clk_hw *hw, unsigned long rate,
+				unsigned long parent_rate)
+{
+	u8 n, k, m, p;
+	u32 reg;
+	struct clk_factors *factors = to_clk_factors(hw);
+	struct clk_factors_config *config = factors->config;
+	unsigned long flags = 0;
+
+	factors->get_factors((u32 *)&rate, &n, &k, &m, &p);
+
+	if (factors->lock)
+		spin_lock_irqsave(factors->lock, flags);
+
+	/* Fetch the register value */
+	reg = readl(factors->reg);
+
+	/* Set up the new factors */
+	reg = FACTOR_SET(config->nshift, config->nwidth, reg, n);
+	reg = FACTOR_SET(config->kshift, config->kwidth, reg, k);
+	reg = FACTOR_SET(config->mshift, config->mwidth, reg, m);
+	reg = FACTOR_SET(config->pshift, config->pwidth, reg, p);
+
+	/* Apply them now */
+	writel(reg, factors->reg);
+
+	/* delay 500us so pll stabilizes */
+	__delay((rate >> 20) * 500 / 2);
+
+	if (factors->lock)
+		spin_unlock_irqrestore(factors->lock, flags);
+
+	return 0;
+}
+
+static const struct clk_ops clk_factors_ops = {
+	.recalc_rate = clk_factors_recalc_rate,
+	.round_rate = clk_factors_round_rate,
+	.set_rate = clk_factors_set_rate,
+};
+
+/**
+ * clk_register_factors - register a factors clock with
+ * the clock framework
+ * @dev: device registering this clock
+ * @name: name of this clock
+ * @parent_name: name of clock's parent
+ * @flags: framework-specific flags
+ * @reg: register address to adjust factors
+ * @config: shift and width of factors n, k, m and p
+ * @get_factors: function to calculate the factors for a given frequency
+ * @lock: shared register lock for this clock
+ */
+struct clk *clk_register_factors(struct device *dev, const char *name,
+				 const char *parent_name,
+				 unsigned long flags, void __iomem *reg,
+				 struct clk_factors_config *config,
+				 void (*get_factors) (u32 *rate, u8 *n, u8 *k,
+						      u8 *m, u8 *p),
+				 spinlock_t *lock)
+{
+	struct clk_factors *factors;
+	struct clk *clk;
+	struct clk_init_data init;
+
+	/* allocate the factors */
+	factors = kzalloc(sizeof(struct clk_factors), GFP_KERNEL);
+	if (!factors) {
+		pr_err("%s: could not allocate factors clk\n", __func__);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	init.name = name;
+	init.ops = &clk_factors_ops;
+	init.flags = flags;
+	init.parent_names = (parent_name ? &parent_name : NULL);
+	init.num_parents = (parent_name ? 1 : 0);
+
+	/* struct clk_factors assignments */
+	factors->reg = reg;
+	factors->config = config;
+	factors->lock = lock;
+	factors->hw.init = &init;
+	factors->get_factors = get_factors;
+
+	/* register the clock */
+	clk = clk_register(dev, &factors->hw);
+
+	if (IS_ERR(clk))
+		kfree(factors);
+
+	return clk;
+}
diff --git a/drivers/clk/sunxi/clk-factors.h b/drivers/clk/sunxi/clk-factors.h
new file mode 100644
index 0000000..a24c889
--- /dev/null
+++ b/drivers/clk/sunxi/clk-factors.h
@@ -0,0 +1,25 @@
+#ifndef __MACH_SUNXI_CLK_FACTORS_H
+#define __MACH_SUNXI_CLK_FACTORS_H
+
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+
+struct clk_factors_config {
+	u8 nshift;
+	u8 nwidth;
+	u8 kshift;
+	u8 kwidth;
+	u8 mshift;
+	u8 mwidth;
+	u8 pshift;
+	u8 pwidth;
+};
+
+struct clk *clk_register_factors(struct device *dev, const char *name,
+				 const char *parent_name,
+				 unsigned long flags, void __iomem *reg,
+				 struct clk_factors_config *config,
+				 void (*get_factors) (u32 *rate, u8 *n, u8 *k,
+						      u8 *m, u8 *p),
+				 spinlock_t *lock);
+#endif
diff --git a/drivers/clk/sunxi/clk-fixed-gate.c b/drivers/clk/sunxi/clk-fixed-gate.c
new file mode 100644
index 0000000..b16eda5
--- /dev/null
+++ b/drivers/clk/sunxi/clk-fixed-gate.c
@@ -0,0 +1,152 @@
+/*
+ * Copyright (C) 2013 Emilio López <emilio at elopez.com.ar>
+ *
+ * Based on drivers/clk/clk-gate.c,
+ *
+ * Copyright (C) 2010-2011 Canonical Ltd <jeremy.kerr at canonical.com>
+ * Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd <mturquette at 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.
+ *
+ * Fixed rate, gated clock implementation
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/string.h>
+
+#include "clk-fixed-gate.h"
+
+/**
+ * DOC: fixed rate clock which can gate and ungate it's ouput
+ *
+ * Traits of this clock:
+ * prepare - clk_(un)prepare only ensures parent is (un)prepared
+ * enable - clk_enable and clk_disable are functional & control gating
+ * rate - rate is always a fixed value.  No clk_set_rate support
+ * parent - fixed parent.  No clk_set_parent support
+ */
+
+struct clk_fixed_gate {
+	struct clk_hw hw;
+	u8            bit_idx;
+	u8            flags;
+	unsigned long fixed_rate;
+	void __iomem  *reg;
+	spinlock_t    *lock;
+};
+
+#define to_clk_fixed_gate(_hw) container_of(_hw, struct clk_fixed_gate, hw)
+
+static void clk_fixed_gate_endisable(struct clk_hw *hw, int enable)
+{
+	struct clk_fixed_gate *gate = to_clk_fixed_gate(hw);
+	unsigned long flags = 0;
+	u32 reg;
+
+	if (gate->lock)
+		spin_lock_irqsave(gate->lock, flags);
+
+	reg = readl(gate->reg);
+
+	if (enable)
+		reg |= BIT(gate->bit_idx);
+	else
+		reg &= ~BIT(gate->bit_idx);
+
+	writel(reg, gate->reg);
+
+	if (gate->lock)
+		spin_unlock_irqrestore(gate->lock, flags);
+}
+
+static int clk_fixed_gate_enable(struct clk_hw *hw)
+{
+	clk_fixed_gate_endisable(hw, 1);
+
+	return 0;
+}
+
+static void clk_fixed_gate_disable(struct clk_hw *hw)
+{
+	clk_fixed_gate_endisable(hw, 0);
+}
+
+static int clk_fixed_gate_is_enabled(struct clk_hw *hw)
+{
+	u32 reg;
+	struct clk_fixed_gate *gate = to_clk_fixed_gate(hw);
+
+	reg = readl(gate->reg);
+
+	reg &= BIT(gate->bit_idx);
+
+	return reg ? 1 : 0;
+}
+
+static unsigned long clk_fixed_gate_recalc_rate(struct clk_hw *hw,
+						unsigned long parent_rate)
+{
+	return to_clk_fixed_gate(hw)->fixed_rate;
+}
+
+static const struct clk_ops clk_fixed_gate_ops = {
+	.enable = clk_fixed_gate_enable,
+	.disable = clk_fixed_gate_disable,
+	.is_enabled = clk_fixed_gate_is_enabled,
+	.recalc_rate = clk_fixed_gate_recalc_rate,
+};
+
+/**
+ * clk_register_fixed_gate - register a fixed rate,
+ * gate clock with the clock framework
+ * @dev: device that is registering this clock
+ * @name: name of this clock
+ * @parent_name: name of this clock's parent
+ * @flags: framework-specific flags for this clock
+ * @reg: register address to control gating of this clock
+ * @bit_idx: which bit in the register controls gating of this clock
+ * @lock: shared register lock for this clock
+ */
+struct clk *clk_register_fixed_gate(struct device *dev, const char *name,
+				    const char *parent_name,
+				    unsigned long flags, void __iomem *reg,
+				    u8 bit_idx, unsigned long fixed_rate,
+				    spinlock_t *lock)
+{
+	struct clk_fixed_gate *gate;
+	struct clk *clk;
+	struct clk_init_data init;
+
+	/* allocate the gate */
+	gate = kzalloc(sizeof(struct clk_fixed_gate), GFP_KERNEL);
+	if (!gate) {
+		pr_err("%s: could not allocate fixed gated clk\n", __func__);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	init.name = name;
+	init.ops = &clk_fixed_gate_ops;
+	init.flags = flags | CLK_IS_BASIC;
+	init.parent_names = (parent_name ? &parent_name : NULL);
+	init.num_parents = (parent_name ? 1 : 0);
+
+	/* struct clk_fixed_gate assignments */
+	gate->fixed_rate = fixed_rate;
+	gate->reg = reg;
+	gate->bit_idx = bit_idx;
+	gate->lock = lock;
+	gate->hw.init = &init;
+
+	clk = clk_register(dev, &gate->hw);
+
+	if (IS_ERR(clk))
+		kfree(gate);
+
+	return clk;
+}
diff --git a/drivers/clk/sunxi/clk-fixed-gate.h b/drivers/clk/sunxi/clk-fixed-gate.h
new file mode 100644
index 0000000..29d9ed3
--- /dev/null
+++ b/drivers/clk/sunxi/clk-fixed-gate.h
@@ -0,0 +1,13 @@
+#ifndef __MACH_SUNXI_CLK_FIXED_GATE_H
+#define __MACH_SUNXI_CLK_FIXED_GATE_H
+
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+
+struct clk *clk_register_fixed_gate(struct device *dev, const char *name,
+				    const char *parent_name,
+				    unsigned long flags, void __iomem *reg,
+				    u8 bit_idx, unsigned long fixed_rate,
+				    spinlock_t *lock);
+
+#endif
diff --git a/drivers/clk/sunxi/clk-sunxi.c b/drivers/clk/sunxi/clk-sunxi.c
new file mode 100644
index 0000000..cb587a0
--- /dev/null
+++ b/drivers/clk/sunxi/clk-sunxi.c
@@ -0,0 +1,265 @@
+/*
+ * Copyright 2013 Emilio López
+ *
+ * Emilio López <emilio at elopez.com.ar>
+ *
+ * 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.
+ *
+ * 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/clkdev.h>
+#include <linux/clk/sunxi.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+
+#include "clk-factors.h"
+#include "clk-fixed-gate.h"
+
+static DEFINE_SPINLOCK(clk_lock);
+
+/**
+ * sunxi_osc_clk_setup() - Setup function for gatable oscillator
+ */
+
+#define SUNXI_OSC24M_GATE	0
+
+static void __init sunxi_osc_clk_setup(struct device_node *node)
+{
+	struct clk *clk;
+	const char *clk_name = node->name;
+	void *reg;
+	u32 rate;
+
+	reg = of_iomap(node, 0);
+
+	if (of_property_read_u32(node, "clock-frequency", &rate))
+		return;
+
+	clk = clk_register_fixed_gate(NULL, clk_name, NULL,
+				      CLK_IS_ROOT | CLK_IGNORE_UNUSED,
+				      reg, SUNXI_OSC24M_GATE, rate, &clk_lock);
+
+	if (clk) {
+		of_clk_add_provider(node, of_clk_src_simple_get, clk);
+		clk_register_clkdev(clk, clk_name, NULL);
+	}
+}
+
+
+
+/**
+ * sunxi_get_pll1_factors() - calculates n, k, m, p factors for PLL1
+ * PLL1 rate is calculated as follows
+ * rate = (parent_rate * n * (k + 1) >> p) / (m + 1);
+ * parent_rate is always 24Mhz
+ */
+
+static void sunxi_get_pll1_factors(u32 *freq, u8 *n, u8 *k, u8 *m, u8 *p)
+{
+	u8 div;
+
+	/* Normalize value to a 6M multiple */
+	div = *freq / 6000000;
+	*freq = 6000000 * div;
+
+	/* we were called to round the frequency, we can now return */
+	if (n == NULL)
+		return;
+
+	/* m is always zero for pll1 */
+	*m = 0;
+
+	/* k is 1 only on these cases */
+	if (*freq >= 768000000 || *freq == 42000000 || *freq == 54000000)
+		*k = 1;
+	else
+		*k = 0;
+
+	/* p will be 3 for divs under 10 */
+	if (div < 10)
+		*p = 3;
+
+	/* p will be 2 for divs between 10 - 20 and odd divs under 32 */
+	else if (div < 20 || (div < 32 && (div & 1)))
+		*p = 2;
+
+	/* p will be 1 for even divs under 32, divs under 40 and odd pairs
+	 * of divs between 40-62 */
+	else if (div < 40 || (div < 64 && (div & 2)))
+		*p = 1;
+
+	/* any other entries have p = 0 */
+	else
+		*p = 0;
+
+	/* calculate a suitable n based on k and p */
+	div <<= *p;
+	div /= (*k + 1);
+	*n = div / 4;
+}
+
+/**
+ * sunxi_pll1_clk_setup() - Setup function for PLL1 clock
+ */
+
+struct clk_factors_config pll1_config = {
+	.nshift = 8,
+	.nwidth = 5,
+	.kshift = 4,
+	.kwidth = 2,
+	.mshift = 0,
+	.mwidth = 2,
+	.pshift = 16,
+	.pwidth = 2,
+};
+
+static void __init sunxi_pll1_clk_setup(struct device_node *node)
+{
+	struct clk *clk;
+	const char *clk_name = node->name;
+	const char *parent;
+	void *reg;
+
+	reg = of_iomap(node, 0);
+
+	parent = of_clk_get_parent_name(node, 0);
+
+	clk = clk_register_factors(NULL, clk_name, parent, CLK_IGNORE_UNUSED,
+				   reg, &pll1_config, sunxi_get_pll1_factors,
+				   &clk_lock);
+
+	if (clk) {
+		of_clk_add_provider(node, of_clk_src_simple_get, clk);
+		clk_register_clkdev(clk, clk_name, NULL);
+	}
+}
+
+
+
+/**
+ * sunxi_cpu_clk_setup() - Setup function for CPU mux
+ */
+
+#define SUNXI_CPU_GATE		16
+#define SUNXI_CPU_GATE_WIDTH	2
+
+static void __init sunxi_cpu_clk_setup(struct device_node *node)
+{
+	struct clk *clk;
+	const char *clk_name = node->name;
+	const char **parents = kmalloc(sizeof(char *) * 5, GFP_KERNEL);
+	void *reg;
+	int i = 0;
+
+	reg = of_iomap(node, 0);
+
+	while (i < 5 && (parents[i] = of_clk_get_parent_name(node, i)) != NULL)
+		i++;
+
+	clk = clk_register_mux(NULL, clk_name, parents, i, 0, reg,
+			       SUNXI_CPU_GATE, SUNXI_CPU_GATE_WIDTH,
+			       0, &clk_lock);
+
+	if (clk) {
+		of_clk_add_provider(node, of_clk_src_simple_get, clk);
+		clk_register_clkdev(clk, clk_name, NULL);
+	}
+}
+
+
+
+/**
+ * sunxi_divider_clk_setup() - Setup function for simple divider clocks
+ */
+
+#define SUNXI_DIVISOR_WIDTH	2
+
+struct div_data {
+	u8 div;
+	u8 pow;
+};
+
+static const __initconst struct div_data axi_data = {
+	.div = 0,
+	.pow = 0,
+};
+
+static const __initconst struct div_data ahb_data = {
+	.div = 4,
+	.pow = 1,
+};
+
+static const __initconst struct div_data apb0_data = {
+	.div = 8,
+	.pow = 1,
+};
+
+static void __init sunxi_divider_clk_setup(struct device_node *node, u8 shift,
+					   u8 power_of_two)
+{
+	struct clk *clk;
+	const char *clk_name = node->name;
+	const char *clk_parent;
+	void *reg;
+
+	reg = of_iomap(node, 0);
+
+	clk_parent = of_clk_get_parent_name(node, 0);
+
+	clk = clk_register_divider(NULL, clk_name, clk_parent, 0,
+				   reg, shift, SUNXI_DIVISOR_WIDTH,
+				   power_of_two ? CLK_DIVIDER_POWER_OF_TWO : 0,
+				   &clk_lock);
+	if (clk) {
+		of_clk_add_provider(node, of_clk_src_simple_get, clk);
+		clk_register_clkdev(clk, clk_name, NULL);
+	}
+}
+
+
+/* Matches for of_clk_init */
+static const __initconst struct of_device_id clk_match[] = {
+	{.compatible = "fixed-clock", .data = of_fixed_clk_setup,},
+	{.compatible = "allwinner,sunxi-osc-clk", .data = sunxi_osc_clk_setup,},
+	{.compatible = "allwinner,sunxi-pll1-clk", .data = sunxi_pll1_clk_setup,},
+	{.compatible = "allwinner,sunxi-cpu-clk", .data = sunxi_cpu_clk_setup,},
+	{}
+};
+
+/* Matches for divider clocks */
+static const __initconst struct of_device_id clk_div_match[] = {
+	{.compatible = "allwinner,sunxi-axi-clk", .data = &axi_data,},
+	{.compatible = "allwinner,sunxi-ahb-clk", .data = &ahb_data,},
+	{.compatible = "allwinner,sunxi-apb0-clk", .data = &apb0_data,},
+	{}
+};
+
+static void __init of_sunxi_divider_clock_setup(void)
+{
+	struct device_node *np;
+	const struct div_data *data;
+	const struct of_device_id *match;
+
+	for_each_matching_node(np, clk_div_match) {
+		match = of_match_node(clk_div_match, np);
+		data = match->data;
+		sunxi_divider_clk_setup(np, data->div, data->pow);
+	}
+}
+
+void __init sunxi_init_clocks(void)
+{
+	/* Register all the simple sunxi clocks on DT */
+	of_clk_init(clk_match);
+
+	/* Register divider clocks */
+	of_sunxi_divider_clock_setup();
+}
-- 
1.8.1.1




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