[PATCH] clk: Add clock driver for AXM55xx SoC
Anders Berg
anders.berg at avagotech.com
Thu May 22 05:14:14 PDT 2014
On Thu, May 15, 2014 at 3:42 PM, Anders Berg <anders.berg at avagotech.com> wrote:
> From: Anders Berg <anders.berg at lsi.com>
>
> 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.berg at lsi.com>
> Cc: Mike Turquette <mturquette at linaro.org>
> Cc: Mark Rutland <mark.rutland at arm.com>
> ---
Mike, any comments on this reworked driver? (you suggested a
simplified binding...)
/Anders
> .../devicetree/bindings/clock/lsi,axm5516-clks.txt | 29 +
> drivers/clk/Makefile | 1 +
> drivers/clk/clk-axm5516.c | 615 +++++++++++++++++++++
> 3 files changed, 645 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/clock/lsi,axm5516-clks.txt
> create mode 100644 drivers/clk/clk-axm5516.c
>
> diff --git a/Documentation/devicetree/bindings/clock/lsi,axm5516-clks.txt b/Documentation/devicetree/bindings/clock/lsi,axm5516-clks.txt
> new file mode 100644
> index 0000000..3ce97cf
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/clock/lsi,axm5516-clks.txt
> @@ -0,0 +1,29 @@
> +AXM5516 clock driver bindings
> +-----------------------------
> +
> +Required properties :
> +- compatible : shall contain "lsi,axm5516-clks"
> +- reg : shall contain base register location and length
> +- #clock-cells : shall contain 1
> +
> +The consumer specifies the desired clock by having the clock ID in its "clocks"
> +phandle cell. See <dt-bindings/clock/lsi,axxia-clock.h> for the list of
> +supported clock IDs.
> +
> +Example:
> +
> + clks: clock-controller at 2010020000 {
> + compatible = "lsi,axm5516-clks";
> + #clock-cells = <1>;
> + reg = <0x20 0x10020000 0 0x20000>;
> + };
> +
> + serial0: uart at 2010080000 {
> + compatible = "arm,pl011", "arm,primecell";
> + reg = <0x20 0x10080000 0 0x1000>;
> + interrupts = <GIC_SPI 56 IRQ_TYPE_LEVEL_HIGH>;
> + clocks = <&clks AXXIA_CLK_PER>;
> + clock-names = "apb_pclk";
> + };
> + };
> +
> diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
> index 5f8a287..32051e7 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-$(CONFIG_ARCH_AXXIA) += clk-axm5516.o
> obj-$(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-axm5516.c b/drivers/clk/clk-axm5516.c
> new file mode 100644
> index 0000000..d2f1e11
> --- /dev/null
> +++ b/drivers/clk/clk-axm5516.c
> @@ -0,0 +1,615 @@
> +/*
> + * drivers/clk/clk-axm5516.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) 2014 LSI Corporation
> + *
> + * 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/platform_device.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/clk-provider.h>
> +#include <linux/regmap.h>
> +#include <dt-bindings/clock/lsi,axm5516-clks.h>
> +
> +
> +/**
> + * struct axxia_clk - Common struct to all Axxia clocks.
> + * @hw: clk_hw for the common clk framework
> + * @regmap: Regmap for the clock control registers
> + */
> +struct axxia_clk {
> + struct clk_hw hw;
> + struct regmap *regmap;
> +};
> +#define to_axxia_clk(_hw) container_of(_hw, struct axxia_clk, hw)
> +
> +/**
> + * struct axxia_pllclk - Axxia PLL generated clock.
> + * @aclk: Common struct
> + * @reg: Offset into regmap for PLL control register
> + */
> +struct axxia_pllclk {
> + struct axxia_clk aclk;
> + u32 reg;
> +};
> +#define to_axxia_pllclk(_aclk) container_of(_aclk, struct axxia_pllclk, aclk)
> +
> +/**
> + * axxia_pllclk_recalc - Calculate the PLL generated clock rate given the
> + * parent clock rate.
> + */
> +static unsigned long
> +axxia_pllclk_recalc(struct clk_hw *hw, unsigned long parent_rate)
> +{
> + struct axxia_clk *aclk = to_axxia_clk(hw);
> + struct axxia_pllclk *pll = to_axxia_pllclk(aclk);
> + unsigned long rate, fbdiv, refdiv, postdiv;
> + u32 control;
> +
> + regmap_read(aclk->regmap, pll->reg, &control);
> + 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 axxia_pllclk_ops = {
> + .recalc_rate = axxia_pllclk_recalc,
> +};
> +
> +/**
> + * struct axxia_divclk - Axxia clock divider
> + * @aclk: Common struct
> + * @reg: Offset into regmap for PLL control register
> + * @shift: Bit position for divider value
> + * @width: Number of bits in divider value
> + */
> +struct axxia_divclk {
> + struct axxia_clk aclk;
> + u32 reg;
> + u32 shift;
> + u32 width;
> +};
> +#define to_axxia_divclk(_aclk) container_of(_aclk, struct axxia_divclk, aclk)
> +
> +/**
> + * axxia_divclk_recalc_rate - Calculate clock divider output rage
> + */
> +static unsigned long
> +axxia_divclk_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
> +{
> + struct axxia_clk *aclk = to_axxia_clk(hw);
> + struct axxia_divclk *divclk = to_axxia_divclk(aclk);
> + u32 ctrl, div;
> +
> + regmap_read(aclk->regmap, divclk->reg, &ctrl);
> + div = 1 + ((ctrl >> divclk->shift) & ((1 << divclk->width)-1));
> +
> + return parent_rate / div;
> +}
> +
> +static const struct clk_ops axxia_divclk_ops = {
> + .recalc_rate = axxia_divclk_recalc_rate,
> +};
> +
> +/**
> + * struct axxia_clkmux - Axxia clock mux
> + * @aclk: Common struct
> + * @reg: Offset into regmap for PLL control register
> + * @shift: Bit position for selection value
> + * @width: Number of bits in selection value
> + */
> +struct axxia_clkmux {
> + struct axxia_clk aclk;
> + u32 reg;
> + u32 shift;
> + u32 width;
> +};
> +#define to_axxia_clkmux(_aclk) container_of(_aclk, struct axxia_clkmux, aclk)
> +
> +/**
> + * axxia_clkmux_get_parent - Return the index of selected parent clock
> + */
> +static u8 axxia_clkmux_get_parent(struct clk_hw *hw)
> +{
> + struct axxia_clk *aclk = to_axxia_clk(hw);
> + struct axxia_clkmux *mux = to_axxia_clkmux(aclk);
> + u32 ctrl, parent;
> +
> + regmap_read(aclk->regmap, mux->reg, &ctrl);
> + parent = (ctrl >> mux->shift) & ((1 << mux->width) - 1);
> +
> + return (u8) parent;
> +}
> +
> +static const struct clk_ops axxia_clkmux_ops = {
> + .get_parent = axxia_clkmux_get_parent,
> +};
> +
> +
> +/*
> + * PLLs
> + */
> +
> +static struct axxia_pllclk clk_fab_pll = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_fab_pll",
> + .parent_names = (const char *[]){
> + "clk_ref0"
> + },
> + .num_parents = 1,
> + .ops = &axxia_pllclk_ops,
> + },
> + .reg = 0x01800,
> +};
> +
> +static struct axxia_pllclk clk_cpu_pll = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_cpu_pll",
> + .parent_names = (const char *[]){
> + "clk_ref0"
> + },
> + .num_parents = 1,
> + .ops = &axxia_pllclk_ops,
> + },
> + .reg = 0x02000,
> +};
> +
> +static struct axxia_pllclk clk_sys_pll = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_sys_pll",
> + .parent_names = (const char *[]){
> + "clk_ref0"
> + },
> + .num_parents = 1,
> + .ops = &axxia_pllclk_ops,
> + },
> + .reg = 0x02800,
> +};
> +
> +static struct axxia_pllclk clk_sm0_pll = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_sm0_pll",
> + .parent_names = (const char *[]){
> + "clk_ref2"
> + },
> + .num_parents = 1,
> + .ops = &axxia_pllclk_ops,
> + },
> + .reg = 0x03000,
> +};
> +
> +static struct axxia_pllclk clk_sm1_pll = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_sm1_pll",
> + .parent_names = (const char *[]){
> + "clk_ref1"
> + },
> + .num_parents = 1,
> + .ops = &axxia_pllclk_ops,
> + },
> + .reg = 0x03800,
> +};
> +
> +/*
> + * Clock dividers
> + */
> +
> +static struct axxia_divclk clk_cpu0_div = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_cpu0_div",
> + .parent_names = (const char *[]){
> + "clk_cpu_pll"
> + },
> + .num_parents = 1,
> + .ops = &axxia_divclk_ops,
> + },
> + .reg = 0x10008,
> + .shift = 0,
> + .width = 4,
> +};
> +
> +static struct axxia_divclk clk_cpu1_div = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_cpu1_div",
> + .parent_names = (const char *[]){
> + "clk_cpu_pll"
> + },
> + .num_parents = 1,
> + .ops = &axxia_divclk_ops,
> + },
> + .reg = 0x10008,
> + .shift = 4,
> + .width = 4,
> +};
> +
> +static struct axxia_divclk clk_cpu2_div = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_cpu2_div",
> + .parent_names = (const char *[]){
> + "clk_cpu_pll"
> + },
> + .num_parents = 1,
> + .ops = &axxia_divclk_ops,
> + },
> + .reg = 0x10008,
> + .shift = 8,
> + .width = 4,
> +};
> +
> +static struct axxia_divclk clk_cpu3_div = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_cpu3_div",
> + .parent_names = (const char *[]){
> + "clk_cpu_pll"
> + },
> + .num_parents = 1,
> + .ops = &axxia_divclk_ops,
> + },
> + .reg = 0x10008,
> + .shift = 12,
> + .width = 4,
> +};
> +
> +static struct axxia_divclk clk_nrcp_div = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_nrcp_div",
> + .parent_names = (const char *[]){
> + "clk_sys_pll"
> + },
> + .num_parents = 1,
> + .ops = &axxia_divclk_ops,
> + },
> + .reg = 0x1000c,
> + .shift = 0,
> + .width = 4,
> +};
> +
> +static struct axxia_divclk clk_sys_div = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_sys_div",
> + .parent_names = (const char *[]){
> + "clk_sys_pll"
> + },
> + .num_parents = 1,
> + .ops = &axxia_divclk_ops,
> + },
> + .reg = 0x1000c,
> + .shift = 4,
> + .width = 4,
> +};
> +
> +static struct axxia_divclk clk_fab_div = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_fab_div",
> + .parent_names = (const char *[]){
> + "clk_fab_pll"
> + },
> + .num_parents = 1,
> + .ops = &axxia_divclk_ops,
> + },
> + .reg = 0x1000c,
> + .shift = 8,
> + .width = 4,
> +};
> +
> +static struct axxia_divclk clk_per_div = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_per_div",
> + .parent_names = (const char *[]){
> + "clk_sm1_pll"
> + },
> + .num_parents = 1,
> + .flags = CLK_IS_BASIC,
> + .ops = &axxia_divclk_ops,
> + },
> + .reg = 0x1000c,
> + .shift = 12,
> + .width = 4,
> +};
> +
> +static struct axxia_divclk clk_mmc_div = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_mmc_div",
> + .parent_names = (const char *[]){
> + "clk_sm1_pll"
> + },
> + .num_parents = 1,
> + .flags = CLK_IS_BASIC,
> + .ops = &axxia_divclk_ops,
> + },
> + .reg = 0x1000c,
> + .shift = 16,
> + .width = 4,
> +};
> +
> +/*
> + * Clock MUXes
> + */
> +
> +static struct axxia_clkmux clk_cpu0_mux = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_cpu0",
> + .parent_names = (const char *[]){
> + "clk_ref0",
> + "clk_cpu_pll",
> + "clk_cpu0_div",
> + "clk_cpu0_div"
> + },
> + .num_parents = 4,
> + .ops = &axxia_clkmux_ops,
> + },
> + .reg = 0x10000,
> + .shift = 0,
> + .width = 2,
> +};
> +
> +static struct axxia_clkmux clk_cpu1_mux = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_cpu1",
> + .parent_names = (const char *[]){
> + "clk_ref0",
> + "clk_cpu_pll",
> + "clk_cpu1_div",
> + "clk_cpu1_div"
> + },
> + .num_parents = 4,
> + .ops = &axxia_clkmux_ops,
> + },
> + .reg = 0x10000,
> + .shift = 2,
> + .width = 2,
> +};
> +
> +static struct axxia_clkmux clk_cpu2_mux = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_cpu2",
> + .parent_names = (const char *[]){
> + "clk_ref0",
> + "clk_cpu_pll",
> + "clk_cpu2_div",
> + "clk_cpu2_div"
> + },
> + .num_parents = 4,
> + .ops = &axxia_clkmux_ops,
> + },
> + .reg = 0x10000,
> + .shift = 4,
> + .width = 2,
> +};
> +
> +static struct axxia_clkmux clk_cpu3_mux = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_cpu3",
> + .parent_names = (const char *[]){
> + "clk_ref0",
> + "clk_cpu_pll",
> + "clk_cpu3_div",
> + "clk_cpu3_div"
> + },
> + .num_parents = 4,
> + .ops = &axxia_clkmux_ops,
> + },
> + .reg = 0x10000,
> + .shift = 6,
> + .width = 2,
> +};
> +
> +static struct axxia_clkmux clk_nrcp_mux = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_nrcp",
> + .parent_names = (const char *[]){
> + "clk_ref0",
> + "clk_sys_pll",
> + "clk_nrcp_div",
> + "clk_nrcp_div"
> + },
> + .num_parents = 4,
> + .ops = &axxia_clkmux_ops,
> + },
> + .reg = 0x10004,
> + .shift = 0,
> + .width = 2,
> +};
> +
> +static struct axxia_clkmux clk_sys_mux = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_sys",
> + .parent_names = (const char *[]){
> + "clk_ref0",
> + "clk_sys_pll",
> + "clk_sys_div",
> + "clk_sys_div"
> + },
> + .num_parents = 4,
> + .ops = &axxia_clkmux_ops,
> + },
> + .reg = 0x10004,
> + .shift = 2,
> + .width = 2,
> +};
> +
> +static struct axxia_clkmux clk_fab_mux = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_fab",
> + .parent_names = (const char *[]){
> + "clk_ref0",
> + "clk_fab_pll",
> + "clk_fab_div",
> + "clk_fab_div"
> + },
> + .num_parents = 4,
> + .ops = &axxia_clkmux_ops,
> + },
> + .reg = 0x10004,
> + .shift = 4,
> + .width = 2,
> +};
> +
> +static struct axxia_clkmux clk_per_mux = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_per",
> + .parent_names = (const char *[]){
> + "clk_ref1",
> + "clk_per_div"
> + },
> + .num_parents = 2,
> + .ops = &axxia_clkmux_ops,
> + },
> + .reg = 0x10004,
> + .shift = 6,
> + .width = 1,
> +};
> +
> +static struct axxia_clkmux clk_mmc_mux = {
> + .aclk.hw.init = &(struct clk_init_data){
> + .name = "clk_mmc",
> + .parent_names = (const char *[]){
> + "clk_ref1",
> + "clk_mmc_div"
> + },
> + .num_parents = 2,
> + .ops = &axxia_clkmux_ops,
> + },
> + .reg = 0x10004,
> + .shift = 9,
> + .width = 1,
> +};
> +
> +/* Table of all supported clocks indexed by the clock identifiers from the
> + * device tree binding
> + */
> +static struct axxia_clk *axmclk_clocks[] = {
> + [AXXIA_CLK_FAB_PLL] = &clk_fab_pll.aclk,
> + [AXXIA_CLK_CPU_PLL] = &clk_cpu_pll.aclk,
> + [AXXIA_CLK_SYS_PLL] = &clk_sys_pll.aclk,
> + [AXXIA_CLK_SM0_PLL] = &clk_sm0_pll.aclk,
> + [AXXIA_CLK_SM1_PLL] = &clk_sm1_pll.aclk,
> + [AXXIA_CLK_FAB_DIV] = &clk_fab_div.aclk,
> + [AXXIA_CLK_SYS_DIV] = &clk_sys_div.aclk,
> + [AXXIA_CLK_NRCP_DIV] = &clk_nrcp_div.aclk,
> + [AXXIA_CLK_CPU0_DIV] = &clk_cpu0_div.aclk,
> + [AXXIA_CLK_CPU1_DIV] = &clk_cpu1_div.aclk,
> + [AXXIA_CLK_CPU2_DIV] = &clk_cpu2_div.aclk,
> + [AXXIA_CLK_CPU3_DIV] = &clk_cpu3_div.aclk,
> + [AXXIA_CLK_PER_DIV] = &clk_per_div.aclk,
> + [AXXIA_CLK_MMC_DIV] = &clk_mmc_div.aclk,
> + [AXXIA_CLK_FAB] = &clk_fab_mux.aclk,
> + [AXXIA_CLK_SYS] = &clk_sys_mux.aclk,
> + [AXXIA_CLK_NRCP] = &clk_nrcp_mux.aclk,
> + [AXXIA_CLK_CPU0] = &clk_cpu0_mux.aclk,
> + [AXXIA_CLK_CPU1] = &clk_cpu1_mux.aclk,
> + [AXXIA_CLK_CPU2] = &clk_cpu2_mux.aclk,
> + [AXXIA_CLK_CPU3] = &clk_cpu3_mux.aclk,
> + [AXXIA_CLK_PER] = &clk_per_mux.aclk,
> + [AXXIA_CLK_MMC] = &clk_mmc_mux.aclk,
> +};
> +
> +static const struct regmap_config axmclk_regmap_config = {
> + .reg_bits = 32,
> + .reg_stride = 4,
> + .val_bits = 32,
> + .max_register = 0x1fffc,
> + .fast_io = true,
> +};
> +
> +static const struct of_device_id axmclk_match_table[] = {
> + { .compatible = "lsi,axm5516-clks" },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, axmclk_match_table);
> +
> +struct axmclk_priv {
> + struct clk_onecell_data onecell;
> + struct clk *clks[];
> +};
> +
> +static int axmclk_probe(struct platform_device *pdev)
> +{
> + void __iomem *base;
> + struct resource *res;
> + int i, ret;
> + struct device *dev = &pdev->dev;
> + struct clk *clk;
> + struct regmap *regmap;
> + size_t num_clks;
> + struct axmclk_priv *priv;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + base = devm_ioremap_resource(dev, res);
> + if (IS_ERR(base))
> + return PTR_ERR(base);
> +
> + regmap = devm_regmap_init_mmio(dev, base, &axmclk_regmap_config);
> + if (IS_ERR(regmap))
> + return PTR_ERR(regmap);
> +
> + num_clks = ARRAY_SIZE(axmclk_clocks);
> + pr_info("axmclk: supporting %u clocks\n", num_clks);
> + priv = devm_kzalloc(dev, sizeof(*priv) + sizeof(*priv->clks) * num_clks,
> + GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
> +
> + priv->onecell.clks = priv->clks;
> + priv->onecell.clk_num = num_clks;
> +
> + /* Update each entry with the allocated regmap and register the clock
> + * with the common clock framework
> + */
> + for (i = 0; i < num_clks; i++) {
> + axmclk_clocks[i]->regmap = regmap;
> + clk = devm_clk_register(dev, &axmclk_clocks[i]->hw);
> + if (IS_ERR(clk))
> + return PTR_ERR(clk);
> + priv->clks[i] = clk;
> + }
> +
> + ret = of_clk_add_provider(dev->of_node,
> + of_clk_src_onecell_get, &priv->onecell);
> +
> + return ret;
> +}
> +
> +static int axmclk_remove(struct platform_device *pdev)
> +{
> + of_clk_del_provider(pdev->dev.of_node);
> + return 0;
> +}
> +
> +static struct platform_driver axmclk_driver = {
> + .probe = axmclk_probe,
> + .remove = axmclk_remove,
> + .driver = {
> + .name = "clk-axm5516",
> + .owner = THIS_MODULE,
> + .of_match_table = axmclk_match_table,
> + },
> +};
> +
> +static int __init axmclk_init(void)
> +{
> + return platform_driver_register(&axmclk_driver);
> +}
> +core_initcall(axmclk_init);
> +
> +static void __exit axmclk_exit(void)
> +{
> + platform_driver_unregister(&axmclk_driver);
> +}
> +module_exit(axmclk_exit);
> +
> +MODULE_DESCRIPTION("AXM5516 clock driver");
> +MODULE_LICENSE("GPL v2");
> +MODULE_ALIAS("platform:clk-axm5516");
> --
> 1.8.3.2
>
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