[PATCH v2] clk: mediatek: Export CPU mux clocks for CPU frequency control

Pi-Cheng Chen pi-cheng.chen at linaro.org
Mon May 18 06:05:16 PDT 2015


Hi Ricky,

On Fri, May 15, 2015 at 2:16 PM, Ricky Liang <jcliang at chromium.org> wrote:
> On Mon, Apr 20, 2015 at 5:25 PM, pi-cheng.chen <pi-cheng.chen at linaro.org> wrote:
>> This patch adds CPU mux clocks which are used by Mediatek cpufreq driver for
>> intermediate clock source switching. It is based on v11 of common clock support
>> for Mediatek MT8135 and MT8173[1]
>>
>> [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2015-April/335967.html
>>
>> Changes in v2:
>> - Remove use of .determine_rate callback
>>
>> Signed-off-by: pi-cheng.chen <pi-cheng.chen at linaro.org>
>> ---
>>  drivers/clk/mediatek/Makefile          |   2 +-
>>  drivers/clk/mediatek/clk-cpumux.c      | 122 +++++++++++++++++++++++++++++++++
>>  drivers/clk/mediatek/clk-cpumux.h      |  31 +++++++++
>>  drivers/clk/mediatek/clk-mt8173.c      |  23 +++++++
>>  include/dt-bindings/clock/mt8173-clk.h |   4 +-
>>  5 files changed, 180 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..dc14074
>> --- /dev/null
>> +++ b/drivers/clk/mediatek/clk-cpumux.c
>> @@ -0,0 +1,122 @@
>> +/*
>> + * Copyright (c) 2015 Linaro Ltd.
>> + * Author: Pi-Cheng Chen <pi-cheng.chen 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.
>> + *
>> + * 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.h>
>> +#include <linux/clk-provider.h>
>> +#include <linux/mfd/syscon.h>
>> +#include <linux/slab.h>
>> +
>> +#include "clk-mtk.h"
>> +#include "clk-cpumux.h"
>> +
>> +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);
>> +       u32 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 struct clk_ops clk_cpumux_ops = {
>> +       .get_parent = clk_cpumux_get_parent,
>> +       .set_parent = clk_cpumux_set_parent,
>> +};
>> +
>> +static struct clk *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;
>
> To be safe, please set
>
>   init.flags = mux->flags;
>
> here

Will fix it.
Thanks for reviewing.

Best Regards,
Pi-Cheng

>
>> +
>> +       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 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;
>> +
>> +       if (!clk_data)
>> +               return -ENOMEM;
>> +
>> +       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..b82ad20
>> --- /dev/null
>> +++ b/drivers/clk/mediatek/clk-cpumux.h
>> @@ -0,0 +1,31 @@
>> +/*
>> + * Copyright (c) 2015 Linaro Ltd.
>> + * Author: Pi-Cheng Chen <pi-cheng.chen 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.
>> + *
>> + * 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
>> +
>> +#include <linux/regmap.h>
>> +
>> +struct mtk_clk_cpumux {
>> +       struct clk_hw   hw;
>> +       struct regmap   *regmap;
>> +       u32             reg;
>> +       u32             mask;
>> +       u8              shift;
>> +};
>> +
>> +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 0584554..745f9d9 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 +518,20 @@ 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 top_muxes[] __initconst = {
>>         /* CLK_CFG_0 */
>>         MUX(TOP_AXI_SEL, "axi_sel", axi_parents, 0x0040, 0, 3),
>> @@ -589,6 +604,11 @@ static const struct mtk_composite top_muxes[] __initconst = {
>>         MUX(TOP_I2S3_B_CK_SEL, "i2s3_b_ck_sel", i2s3_b_ck_parents, 0x120, 8, 1),
>>  };
>>
>> +static const struct mtk_composite cpu_muxes[] __initconst = {
>> +       MUX(INFRA_CA53SEL, "infra_ca53_sel", ca53_parents, 0x0000, 0, 2),
>> +       MUX(INFRA_CA57SEL, "infra_ca57_sel", ca57_parents, 0x0000, 2, 2),
>> +};
>> +
>>  static void __init mtk_init_clk_topckgen(void __iomem *top_base,
>>                 struct clk_onecell_data *clk_data)
>>  {
>> @@ -745,6 +765,9 @@ static void __init mtk_infrasys_init(struct device_node *node)
>>         mtk_clk_register_gates(node, infra_clks, ARRAY_SIZE(infra_clks),
>>                                                 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 e648b28..2503b03 100644
>> --- a/include/dt-bindings/clock/mt8173-clk.h
>> +++ b/include/dt-bindings/clock/mt8173-clk.h
>> @@ -187,7 +187,9 @@
>>  #define INFRA_CEC              9
>>  #define INFRA_PMICSPI          10
>>  #define INFRA_PMICWRAP         11
>> -#define INFRA_NR_CLK           12
>> +#define INFRA_CA53SEL          12
>> +#define INFRA_CA57SEL          13
>> +#define INFRA_NR_CLK           14
>>
>>  /* PERI_SYS */
>>
>> --
>> 1.9.1
>>
>>
>> _______________________________________________
>> Linux-mediatek mailing list
>> Linux-mediatek at lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-mediatek



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