Add clk driver to support clock blocks found on the AXM55xx devices. The driver
provides clock implementations for three different types of clock devices on
the AXM55xx device: PLL clock, a clock divider and a clock mux.
Signed-off-by: Anders Berg <anders.b...@lsi.com>
---
.../devicetree/bindings/clock/clk-axxia.txt | 88 +++++++
drivers/clk/Makefile | 1 +
drivers/clk/clk-axxia.c | 281 +++++++++++++++++++++
3 files changed, 370 insertions(+)
create mode 100644 Documentation/devicetree/bindings/clock/clk-axxia.txt
create mode 100644 drivers/clk/clk-axxia.c
diff --git a/Documentation/devicetree/bindings/clock/clk-axxia.txt
b/Documentation/devicetree/bindings/clock/clk-axxia.txt
new file mode 100644
index 0000000..94eb840
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/clk-axxia.txt
@@ -0,0 +1,88 @@
+* Axxia clock driver bindings
+
+This document contains bindings for the Axxia PLL, clock divider and mux. The
+binding uses the common clock binding found in:
+
+ Documentation/devicetree/bindings/clock/clock-bindings.txt
+
+* Axxia PLL
+
+Required properties:
+- #clock-cells : shall be set to 0.
+- compatible : shall be "lsi,axxia-pll-clock"
+- clocks : parent clock phandle
+- reg - specifies PLL control registers
+
+Optional properties:
+- clock-output-names : From common clock binding.
+
+Example:
+
+ clk_ref0: clk_ref0 {
+ compatible = "fixed-clock";
+ #clock-cells = <0>;
+ clock-frequency = <125000000>;
+ };
+
+ clk_cpu_pll: clk_cpu_pll@2010022000 {
+ compatible = "lsi,axxia-pll-clock";
+ #clock-cells = <0>;
+ clocks = <&clk_ref0>;
+ clock-output-names = "clk_cpu_pll";
+ reg = <0x20 0x10022000 0 0x2c>;
+ };
+
+
+* Axxia clock divider
+
+Required properties:
+- #clock-cells : shall be set to 0.
+- compatible : shall be "lsi,axxia-div-clock"
+- clocks : parent clock phandle
+- reg - clock divider control register
+- lsi,bit-shift : bit position of the divider control field.
+- lsi,bit-mask : width of the divider control field.
+
+Optional properties:
+- clock-output-names : From common clock binding.
+
+Example:
+
+ clk_cpu_div: cpu {
+ compatible = "lsi,axxia-div-clock";
+ #clock-cells = <0>;
+ clocks = <&clk_cpu_pll>;
+ clock-output-names = "clk_cpu_div";
+ reg = <0x20 0x10030008 0 0x4>;
+ lsi,bit-shift = <0>;
+ lsi,bit-width = <4>;
+ };
+
+
+* Axxia clock mux
+
+Required properties:
+- #clock-cells : shall be set to 0.
+- compatible : shall be "lsi,axxia-mux-clock"
+- clocks : phandle of parent clocks (max 4)
+- reg - clock divider control register
+- lsi,bit-shift : bit position of the divider control field.
+- lsi,bit-mask : width of the divider control field.
+
+Optional properties:
+- clock-output-names : From common clock binding.
+
+Example:
+
+ clk_cpu: clk_cpu0@2010030000 {
+ compatible = "lsi,axxia-mux-clock";
+ #clock-cells = <0>;
+ clocks = <&clk_ref0>,
+ <&clk_cpu_pll>,
+ <&clk_cpu_div>,
+ <&clk_cpu_div>;
+ clock-output-names = "clk_cpu";
+ reg = <0x20 0x10030000 0 0x4>;
+ lsi,bit-shift = <0>;
+ lsi,bit-width = <2>;
+ };
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 88af4a3..a9d0626 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_COMMON_CLK) += clk-composite.o
# hardware specific clock types
# please keep this section sorted lexicographically by file/directory path name
obj-$(CONFIG_COMMON_CLK_AXI_CLKGEN) += clk-axi-clkgen.o
+obj-$(CONFIG_ARCH_AXXIA) += clk-axxia.o
obj-$(CONFIG_ARCH_BCM2835) += clk-bcm2835.o
obj-$(CONFIG_ARCH_EFM32) += clk-efm32gg.o
obj-$(CONFIG_ARCH_HIGHBANK) += clk-highbank.o
diff --git a/drivers/clk/clk-axxia.c b/drivers/clk/clk-axxia.c
new file mode 100644
index 0000000..996b8f2
--- /dev/null
+++ b/drivers/clk/clk-axxia.c
@@ -0,0 +1,281 @@
+/*
+ * arch/arm/mach-axxia/clock.c
+ *
+ * Provides clock implementations for three different types of clock devices on
+ * the Axxia device: PLL clock, a clock divider and a clock mux.
+ *
+ * Copyright (C) 2012 LSI
+ *
+ * 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.
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/clk-provider.h>
+
+
+static void __iomem *
+parse_and_map_reg(struct device_node *node, u32 *shift, u32 *width)
+{
+ void __iomem *reg;
+
+ if (of_property_read_u32(node, "lsi,bit-shift", shift)) {
+ pr_err("%s: no 'lsi,bit-shift' property\n", node->name);
+ return NULL;
+ }
+
+ if (of_property_read_u32(node, "lsi,bit-width", width)) {
+ pr_err("%s: no 'lsi,bit-width' property\n", node->name);
+ return NULL;
+ }
+
+ reg = of_iomap(node, 0);
+ if (!reg)
+ pr_err("%s: failed to map register\n", node->name);
+
+ return reg;
+}
+
+/**
+ * struct axxia_pllclk - Axxia PLL generated clock.
+ * @hw: clk_hw for the PLL
+ * @regs: Pointer to control registers
+ */
+struct axxia_pllclk {
+ struct clk_hw hw;
+ void __iomem *regs;
+};
+
+#define to_axxia_pll(_hw) container_of(_hw, struct axxia_pllclk, hw)
+
+static unsigned long
+axxia_pllclk_recalc(struct clk_hw *hw, unsigned long parent_rate)
+{
+ struct axxia_pllclk *pll = to_axxia_pll(hw);
+ unsigned long rate, fbdiv, refdiv, postdiv;
+ u32 control;
+
+ control = readl(pll->regs);
+ postdiv = ((control >> 0) & 0xf) + 1;
+ fbdiv = ((control >> 4) & 0xfff) + 3;
+ refdiv = ((control >> 16) & 0x1f) + 1;
+ rate = (parent_rate / (refdiv * postdiv)) * fbdiv;
+
+ return rate;
+}
+
+static const struct clk_ops clk_pll_ops = {
+ .recalc_rate = axxia_pllclk_recalc,
+};
+
+static struct clk *
+register_axxia_pllclk(struct device *dev, const char *name,
+ const char *parent_name, void __iomem *regs)
+{
+ struct clk_init_data init;
+ struct axxia_pllclk *pll;
+ struct clk *clk;
+
+ pll = kzalloc(sizeof(*pll), GFP_KERNEL);
+ if (!pll)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &clk_pll_ops;
+ init.flags = 0;
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+
+ pll->regs = regs;
+ pll->hw.init = &init;
+
+ clk = clk_register(NULL, &pll->hw);
+ if (IS_ERR(clk))
+ kfree(pll);
+
+ return clk;
+}
+
+
+/**
+ * struct axxia_divclk - Axxia clock divider
+ * @hw: clk_hw for the divider
+ * @regs: Pointer to control registers
+ */
+struct axxia_divclk {
+ struct clk_hw hw;
+ void __iomem *regs;
+ int shift;
+ int width;
+};
+
+#define to_axxia_divclk(_hw) container_of(_hw, struct axxia_divclk, hw)
+
+static unsigned long
+axxia_divclk_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
+{
+ struct axxia_divclk *divclk = to_axxia_divclk(hw);
+ u32 ctrl, div;
+
+ ctrl = readl(divclk->regs);
+ div = 1 + ((ctrl >> divclk->shift) & GENMASK(divclk->width-1, 0));
+
+ return parent_rate / div;
+}
+
+const struct clk_ops axxia_divclk_ops = {
+ .recalc_rate = axxia_divclk_recalc_rate,
+};
+
+static struct clk *
+register_axxia_divclk(struct device *dev, const char *name,
+ const char *parent_name, void __iomem *regs,
+ int shift, int width)
+{
+ struct axxia_divclk *div;
+ struct clk *clk;
+ struct clk_init_data init;
+
+ div = kzalloc(sizeof(struct axxia_divclk), GFP_KERNEL);
+ if (!div)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &axxia_divclk_ops;
+ init.flags = CLK_IS_BASIC;
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+
+ div->regs = regs;
+ div->shift = shift;
+ div->width = width;
+ div->hw.init = &init;
+
+ /* register the clock */
+ clk = clk_register(dev, &div->hw);
+ if (IS_ERR(clk))
+ kfree(div);
+
+ return clk;
+}
+
+/**
+ * axxia_pll_clk_init - Axxia PLL clock setup function
+ * @node: pointer to device tree node
+ */
+static void __init
+axxia_pll_clk_init(struct device_node *node)
+{
+ struct clk *clk;
+ const char *parent_name;
+ void __iomem *regs;
+ const char *clk_name = node->name;
+
+ of_property_read_string(node, "clock-output-names", &clk_name);
+
+ parent_name = of_clk_get_parent_name(node, 0);
+ if (!parent_name) {
+ pr_err("%s: no parent clock\n", node->name);
+ return;
+ }
+
+ regs = of_iomap(node, 0);
+ if (!regs) {
+ pr_err("%s: failed to map register\n", node->name);
+ return;
+ }
+
+ clk = register_axxia_pllclk(NULL, clk_name, parent_name, regs);
+ if (IS_ERR(clk)) {
+ pr_err("%s: register failed (%ld)\n", clk_name, PTR_ERR(clk));
+ iounmap(regs);
+ return;
+ }
+
+ of_clk_add_provider(node, of_clk_src_simple_get, clk);
+}
+CLK_OF_DECLARE(axxia_pll_clk, "lsi,axxia-pll-clock", axxia_pll_clk_init);
+
+
+/**
+ * axxia_div_clk_init - Axxia clock divider setup function
+ * @node: device tree node for this clock
+ */
+static void __init
+axxia_div_clk_init(struct device_node *node)
+{
+ const char *parent_name;
+ void __iomem *reg;
+ u32 shift, width;
+ struct clk *clk;
+ const char *clk_name = node->name;
+
+ of_property_read_string(node, "clock-output-names", &clk_name);
+
+ parent_name = of_clk_get_parent_name(node, 0);
+ if (!parent_name) {
+ pr_err("%s: no parent clock\n", node->name);
+ return;
+ }
+
+ reg = parse_and_map_reg(node, &shift, &width);
+ if (!reg)
+ return;
+
+ clk = register_axxia_divclk(NULL, clk_name, parent_name, reg,
+ shift, width);
+ if (IS_ERR(clk)) {
+ pr_err("%s: register failed (%ld)\n", clk_name, PTR_ERR(clk));
+ iounmap(reg);
+ return;
+ }
+
+ of_clk_add_provider(node, of_clk_src_simple_get, clk);
+}
+CLK_OF_DECLARE(axxia_div_clk, "lsi,axxia-div-clock", axxia_div_clk_init);
+
+
+/**
+ * axxia_mux_clk_init - Clock mux setup function
+ * @node: device tree node for this clock
+ */
+static void __init
+axxia_mux_clk_init(struct device_node *node)
+{
+ void __iomem *reg;
+ struct clk *clk;
+ const char *parents[4];
+ int num_parents;
+ const char *clk_name = node->name;
+ u32 shift, width;
+ int i;
+
+ of_property_read_string(node, "clock-output-names", &clk_name);
+
+ for (i = 0; i < ARRAY_SIZE(parents); ++i) {
+ parents[i] = of_clk_get_parent_name(node, i);
+ if (!parents[i])
+ break;
+ }
+ num_parents = i;
+
+ reg = parse_and_map_reg(node, &shift, &width);
+ if (!reg)
+ return;
+
+ clk = clk_register_mux(NULL, clk_name, parents,
+ num_parents, 0, reg, shift, width,
+ CLK_MUX_READ_ONLY, NULL);
+ if (IS_ERR(clk)) {
+ pr_err("%s: register failed (%ld)\n", clk_name, PTR_ERR(clk));
+ iounmap(reg);
+ return;
+ }
+
+ of_clk_add_provider(node, of_clk_src_simple_get, clk);
+}
+CLK_OF_DECLARE(pll_mux_clock, "lsi,axxia-mux-clock", axxia_mux_clk_init);
--
1.8.3.2
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