[PATCH V3 1/3] clk: ux500: Add support for sysctrl clocks

Ulf Hansson ulf.hansson at linaro.org
Wed Apr 10 04:02:53 EDT 2013


On 9 April 2013 03:14, Mike Turquette <mturquette at linaro.org> wrote:
> Quoting Ulf Hansson (2013-04-03 05:26:57)
>> From: Ulf Hansson <ulf.hansson at linaro.org>
>>
>> The abx500 sysctrl clocks are using the ab8500 sysctrl driver to
>> modify the clock hardware. Sysctrl clocks are represented by a
>> ab8500 sysctrl register and with a corresponding bitmask.
>>
>> The sysctrl clocks are slow path clocks, which means clk_prepare
>> and clk_unprepare will be used to gate|ungate these clocks.
>>
>> Signed-off-by: Ulf Hansson <ulf.hansson at linaro.org>
>
> Hi Ulf,
>
> Is there a V3 update for patches #2 & #3?  I can't seem to find them.

Hi Mike,

Only v3 exist for this patch. Sorry if it was a bit unclear.

Kind regards
Uffe

>
> Regards,
> Mike
>
>> ---
>>
>> Changes in v3:
>>         - Fixed error check at clk registration.
>> Changes in v2:
>>         - Removed wrong header file.
>> ---
>>  drivers/clk/ux500/Makefile      |    1 +
>>  drivers/clk/ux500/clk-sysctrl.c |  221 +++++++++++++++++++++++++++++++++++++++
>>  drivers/clk/ux500/clk.h         |   29 +++++
>>  3 files changed, 251 insertions(+)
>>  create mode 100644 drivers/clk/ux500/clk-sysctrl.c
>>
>> diff --git a/drivers/clk/ux500/Makefile b/drivers/clk/ux500/Makefile
>> index bcc0c11..c6a806e 100644
>> --- a/drivers/clk/ux500/Makefile
>> +++ b/drivers/clk/ux500/Makefile
>> @@ -5,6 +5,7 @@
>>  # Clock types
>>  obj-y += clk-prcc.o
>>  obj-y += clk-prcmu.o
>> +obj-y += clk-sysctrl.o
>>
>>  # Clock definitions
>>  obj-y += u8500_clk.o
>> diff --git a/drivers/clk/ux500/clk-sysctrl.c b/drivers/clk/ux500/clk-sysctrl.c
>> new file mode 100644
>> index 0000000..bc7e9bd
>> --- /dev/null
>> +++ b/drivers/clk/ux500/clk-sysctrl.c
>> @@ -0,0 +1,221 @@
>> +/*
>> + * Sysctrl clock implementation for ux500 platform.
>> + *
>> + * Copyright (C) 2013 ST-Ericsson SA
>> + * Author: Ulf Hansson <ulf.hansson at linaro.org>
>> + *
>> + * License terms: GNU General Public License (GPL) version 2
>> + */
>> +
>> +#include <linux/clk-provider.h>
>> +#include <linux/mfd/abx500/ab8500-sysctrl.h>
>> +#include <linux/device.h>
>> +#include <linux/slab.h>
>> +#include <linux/delay.h>
>> +#include <linux/io.h>
>> +#include <linux/err.h>
>> +#include "clk.h"
>> +
>> +#define SYSCTRL_MAX_NUM_PARENTS 4
>> +
>> +#define to_clk_sysctrl(_hw) container_of(_hw, struct clk_sysctrl, hw)
>> +
>> +struct clk_sysctrl {
>> +       struct clk_hw hw;
>> +       struct device *dev;
>> +       u8 parent_index;
>> +       u16 reg_sel[SYSCTRL_MAX_NUM_PARENTS];
>> +       u8 reg_mask[SYSCTRL_MAX_NUM_PARENTS];
>> +       u8 reg_bits[SYSCTRL_MAX_NUM_PARENTS];
>> +       unsigned long rate;
>> +       unsigned long enable_delay_us;
>> +};
>> +
>> +/* Sysctrl clock operations. */
>> +
>> +static int clk_sysctrl_prepare(struct clk_hw *hw)
>> +{
>> +       int ret;
>> +       struct clk_sysctrl *clk = to_clk_sysctrl(hw);
>> +
>> +       ret = ab8500_sysctrl_write(clk->reg_sel[0], clk->reg_mask[0],
>> +                               clk->reg_bits[0]);
>> +
>> +       if (!ret && clk->enable_delay_us)
>> +               usleep_range(clk->enable_delay_us, clk->enable_delay_us);
>> +
>> +       return ret;
>> +}
>> +
>> +static void clk_sysctrl_unprepare(struct clk_hw *hw)
>> +{
>> +       struct clk_sysctrl *clk = to_clk_sysctrl(hw);
>> +       if (ab8500_sysctrl_clear(clk->reg_sel[0], clk->reg_mask[0]))
>> +               dev_err(clk->dev, "clk_sysctrl: %s fail to clear %s.\n",
>> +                       __func__, __clk_get_name(hw->clk));
>> +}
>> +
>> +static unsigned long clk_sysctrl_recalc_rate(struct clk_hw *hw,
>> +                                       unsigned long parent_rate)
>> +{
>> +       struct clk_sysctrl *clk = to_clk_sysctrl(hw);
>> +       return clk->rate;
>> +}
>> +
>> +static int clk_sysctrl_set_parent(struct clk_hw *hw, u8 index)
>> +{
>> +       struct clk_sysctrl *clk = to_clk_sysctrl(hw);
>> +       u8 old_index = clk->parent_index;
>> +       int ret = 0;
>> +
>> +       if (clk->reg_sel[old_index]) {
>> +               ret = ab8500_sysctrl_clear(clk->reg_sel[old_index],
>> +                                       clk->reg_mask[old_index]);
>> +               if (ret)
>> +                       return ret;
>> +       }
>> +
>> +       if (clk->reg_sel[index]) {
>> +               ret = ab8500_sysctrl_write(clk->reg_sel[index],
>> +                                       clk->reg_mask[index],
>> +                                       clk->reg_bits[index]);
>> +               if (ret) {
>> +                       if (clk->reg_sel[old_index])
>> +                               ab8500_sysctrl_write(clk->reg_sel[old_index],
>> +                                               clk->reg_mask[old_index],
>> +                                               clk->reg_bits[old_index]);
>> +                       return ret;
>> +               }
>> +       }
>> +       clk->parent_index = index;
>> +
>> +       return ret;
>> +}
>> +
>> +static u8 clk_sysctrl_get_parent(struct clk_hw *hw)
>> +{
>> +       struct clk_sysctrl *clk = to_clk_sysctrl(hw);
>> +       return clk->parent_index;
>> +}
>> +
>> +static struct clk_ops clk_sysctrl_gate_ops = {
>> +       .prepare = clk_sysctrl_prepare,
>> +       .unprepare = clk_sysctrl_unprepare,
>> +};
>> +
>> +static struct clk_ops clk_sysctrl_gate_fixed_rate_ops = {
>> +       .prepare = clk_sysctrl_prepare,
>> +       .unprepare = clk_sysctrl_unprepare,
>> +       .recalc_rate = clk_sysctrl_recalc_rate,
>> +};
>> +
>> +static struct clk_ops clk_sysctrl_set_parent_ops = {
>> +       .set_parent = clk_sysctrl_set_parent,
>> +       .get_parent = clk_sysctrl_get_parent,
>> +};
>> +
>> +static struct clk *clk_reg_sysctrl(struct device *dev,
>> +                               const char *name,
>> +                               const char **parent_names,
>> +                               u8 num_parents,
>> +                               u16 *reg_sel,
>> +                               u8 *reg_mask,
>> +                               u8 *reg_bits,
>> +                               unsigned long rate,
>> +                               unsigned long enable_delay_us,
>> +                               unsigned long flags,
>> +                               struct clk_ops *clk_sysctrl_ops)
>> +{
>> +       struct clk_sysctrl *clk;
>> +       struct clk_init_data clk_sysctrl_init;
>> +       struct clk *clk_reg;
>> +       int i;
>> +
>> +       if (!dev)
>> +               return ERR_PTR(-EINVAL);
>> +
>> +       if (!name || (num_parents > SYSCTRL_MAX_NUM_PARENTS)) {
>> +               dev_err(dev, "clk_sysctrl: invalid arguments passed\n");
>> +               return ERR_PTR(-EINVAL);
>> +       }
>> +
>> +       clk = devm_kzalloc(dev, sizeof(struct clk_sysctrl), GFP_KERNEL);
>> +       if (!clk) {
>> +               dev_err(dev, "clk_sysctrl: could not allocate clk\n");
>> +               return ERR_PTR(-ENOMEM);
>> +       }
>> +
>> +       for (i = 0; i < num_parents; i++) {
>> +               clk->reg_sel[i] = reg_sel[i];
>> +               clk->reg_bits[i] = reg_bits[i];
>> +               clk->reg_mask[i] = reg_mask[i];
>> +       }
>> +
>> +       clk->parent_index = 0;
>> +       clk->rate = rate;
>> +       clk->enable_delay_us = enable_delay_us;
>> +       clk->dev = dev;
>> +
>> +       clk_sysctrl_init.name = name;
>> +       clk_sysctrl_init.ops = clk_sysctrl_ops;
>> +       clk_sysctrl_init.flags = flags;
>> +       clk_sysctrl_init.parent_names = parent_names;
>> +       clk_sysctrl_init.num_parents = num_parents;
>> +       clk->hw.init = &clk_sysctrl_init;
>> +
>> +       clk_reg = devm_clk_register(clk->dev, &clk->hw);
>> +       if (IS_ERR(clk_reg))
>> +               dev_err(dev, "clk_sysctrl: clk_register failed\n");
>> +
>> +       return clk_reg;
>> +}
>> +
>> +struct clk *clk_reg_sysctrl_gate(struct device *dev,
>> +                               const char *name,
>> +                               const char *parent_name,
>> +                               u16 reg_sel,
>> +                               u8 reg_mask,
>> +                               u8 reg_bits,
>> +                               unsigned long enable_delay_us,
>> +                               unsigned long flags)
>> +{
>> +       const char **parent_names = (parent_name ? &parent_name : NULL);
>> +       u8 num_parents = (parent_name ? 1 : 0);
>> +
>> +       return clk_reg_sysctrl(dev, name, parent_names, num_parents,
>> +                       &reg_sel, &reg_mask, &reg_bits, 0, enable_delay_us,
>> +                       flags, &clk_sysctrl_gate_ops);
>> +}
>> +
>> +struct clk *clk_reg_sysctrl_gate_fixed_rate(struct device *dev,
>> +                                       const char *name,
>> +                                       const char *parent_name,
>> +                                       u16 reg_sel,
>> +                                       u8 reg_mask,
>> +                                       u8 reg_bits,
>> +                                       unsigned long rate,
>> +                                       unsigned long enable_delay_us,
>> +                                       unsigned long flags)
>> +{
>> +       const char **parent_names = (parent_name ? &parent_name : NULL);
>> +       u8 num_parents = (parent_name ? 1 : 0);
>> +
>> +       return clk_reg_sysctrl(dev, name, parent_names, num_parents,
>> +                       &reg_sel, &reg_mask, &reg_bits,
>> +                       rate, enable_delay_us, flags,
>> +                       &clk_sysctrl_gate_fixed_rate_ops);
>> +}
>> +
>> +struct clk *clk_reg_sysctrl_set_parent(struct device *dev,
>> +                               const char *name,
>> +                               const char **parent_names,
>> +                               u8 num_parents,
>> +                               u16 *reg_sel,
>> +                               u8 *reg_mask,
>> +                               u8 *reg_bits,
>> +                               unsigned long flags)
>> +{
>> +       return clk_reg_sysctrl(dev, name, parent_names, num_parents,
>> +                       reg_sel, reg_mask, reg_bits, 0, 0, flags,
>> +                       &clk_sysctrl_set_parent_ops);
>> +}
>> diff --git a/drivers/clk/ux500/clk.h b/drivers/clk/ux500/clk.h
>> index c3e4491..3d2dfdc 100644
>> --- a/drivers/clk/ux500/clk.h
>> +++ b/drivers/clk/ux500/clk.h
>> @@ -11,6 +11,7 @@
>>  #define __UX500_CLK_H
>>
>>  #include <linux/clk.h>
>> +#include <linux/device.h>
>>
>>  struct clk *clk_reg_prcc_pclk(const char *name,
>>                               const char *parent_name,
>> @@ -57,4 +58,32 @@ struct clk *clk_reg_prcmu_opp_volt_scalable(const char *name,
>>                                             unsigned long rate,
>>                                             unsigned long flags);
>>
>> +struct clk *clk_reg_sysctrl_gate(struct device *dev,
>> +                                const char *name,
>> +                                const char *parent_name,
>> +                                u16 reg_sel,
>> +                                u8 reg_mask,
>> +                                u8 reg_bits,
>> +                                unsigned long enable_delay_us,
>> +                                unsigned long flags);
>> +
>> +struct clk *clk_reg_sysctrl_gate_fixed_rate(struct device *dev,
>> +                                           const char *name,
>> +                                           const char *parent_name,
>> +                                           u16 reg_sel,
>> +                                           u8 reg_mask,
>> +                                           u8 reg_bits,
>> +                                           unsigned long rate,
>> +                                           unsigned long enable_delay_us,
>> +                                           unsigned long flags);
>> +
>> +struct clk *clk_reg_sysctrl_set_parent(struct device *dev,
>> +                                      const char *name,
>> +                                      const char **parent_names,
>> +                                      u8 num_parents,
>> +                                      u16 *reg_sel,
>> +                                      u8 *reg_mask,
>> +                                      u8 *reg_bits,
>> +                                      unsigned long flags);
>> +
>>  #endif /* __UX500_CLK_H */
>> --
>> 1.7.10



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