Re: [RESEND PATCH v5] clk: mediatek: Export CPU mux clocks for CPU frequency control

Daniel Kurtz
2015-09-14T07:22:51Z

On Mon, Aug 17, 2015 at 4:56 PM, Pi-Cheng Chen <pi-cheng.chen@linaro.org> wrote:
> From: "pi-cheng.chen" <pi-cheng.chen@linaro.org>
>
> 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>
> Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
> ---
> Changes in v5:
> - Replace __initdata with __initconst to fix compiling error
>
> Changes in v4:
> - Fix some minor issues for v3
> - Rebase to the patch that adds 13mhz clock for MT8173[1]
>
> Changes in v3:
> - Rebase to 4.2-rc1
> - Fix some issues of v2
>
> Changes in v2:
> - Remove use of .determine_rate callback
>
> [1] http://patchwork.kernerl.xyz/patch/6777041/
> ---
> drivers/clk/mediatek/Makefile | 2 +-
> drivers/clk/mediatek/clk-cpumux.c | 127 +++++++++++++++++++++++++++++++++
> drivers/clk/mediatek/clk-cpumux.h | 22 ++++++
> drivers/clk/mediatek/clk-mt8173.c | 23 ++++++
> include/dt-bindings/clock/mt8173-clk.h | 4 +-
> 5 files changed, 176 insertions(+), 2 deletions(-)
> create mode 100644 drivers/clk/mediatek/clk-cpumux.c
> create mode 100644 drivers/clk/mediatek/clk-cpumux.h
>
> diff --git a/drivers/clk/mediatek/Makefile b/drivers/clk/mediatek/Makefile
> index 8e4b2a4..299917a 100644
> --- a/drivers/clk/mediatek/Makefile
> +++ b/drivers/clk/mediatek/Makefile
> @@ -1,4 +1,4 @@
> -obj-y += clk-mtk.o clk-pll.o clk-gate.o
> +obj-y += clk-mtk.o clk-pll.o clk-gate.o clk-cpumux.o
> obj-$(CONFIG_RESET_CONTROLLER) += reset.o
> obj-y += clk-mt8135.o
> obj-y += clk-mt8173.o
> diff --git a/drivers/clk/mediatek/clk-cpumux.c b/drivers/clk/mediatek/clk-cpumux.c
> new file mode 100644
> index 0000000..fb04fe1
> --- /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_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_clk_mux(hw);
> + int num_parents = __clk_get_num_parents(hw->clk);

This will no longer compile against v4.3-rc1 due to:

commit fc4a05d4b0eb1a0110ef11201bf563cd4b53fbce
clk: Remove unused provider APIs

Use the following instead:

unsigned 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_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;
> +}
> diff --git a/drivers/clk/mediatek/clk-cpumux.h b/drivers/clk/mediatek/clk-cpumux.h
> new file mode 100644
> index 0000000..52c769f
> --- /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 */
> diff --git a/drivers/clk/mediatek/clk-mt8173.c b/drivers/clk/mediatek/clk-mt8173.c
> index 540c5c3..053ca27 100644
> --- a/drivers/clk/mediatek/clk-mt8173.c
> +++ b/drivers/clk/mediatek/clk-mt8173.c
> @@ -19,6 +19,7 @@
>
> #include "clk-mtk.h"
> #include "clk-gate.h"
> +#include "clk-cpumux.h"
>
> #include <dt-bindings/clock/mt8173-clk.h>
>
> @@ -517,6 +518,25 @@ static const char * const i2s3_b_ck_parents[] __initconst = {
> "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),
> @@ -743,6 +763,9 @@ static void __init mtk_infrasys_init(struct device_node *node)
> 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",
> diff --git a/include/dt-bindings/clock/mt8173-clk.h b/include/dt-bindings/clock/mt8173-clk.h
> index fa2a2bb..a17cbaa 100644
> --- a/include/dt-bindings/clock/mt8173-clk.h
> +++ b/include/dt-bindings/clock/mt8173-clk.h
> @@ -188,7 +188,9 @@
> #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 */
>
> --
> 1.9.1
>