diff options
Diffstat (limited to 'drivers/clk/ux500/clk-prcmu.c')
| -rw-r--r-- | drivers/clk/ux500/clk-prcmu.c | 252 | 
1 files changed, 252 insertions, 0 deletions
diff --git a/drivers/clk/ux500/clk-prcmu.c b/drivers/clk/ux500/clk-prcmu.c new file mode 100644 index 00000000000..930cdfeb47a --- /dev/null +++ b/drivers/clk/ux500/clk-prcmu.c @@ -0,0 +1,252 @@ +/* + * PRCMU clock implementation for ux500 platform. + * + * Copyright (C) 2012 ST-Ericsson SA + * Author: Ulf Hansson <ulf.hansson@linaro.org> + * + * License terms: GNU General Public License (GPL) version 2 + */ + +#include <linux/clk-provider.h> +#include <linux/clk-private.h> +#include <linux/mfd/dbx500-prcmu.h> +#include <linux/slab.h> +#include <linux/io.h> +#include <linux/err.h> +#include "clk.h" + +#define to_clk_prcmu(_hw) container_of(_hw, struct clk_prcmu, hw) + +struct clk_prcmu { +	struct clk_hw hw; +	u8 cg_sel; +	int is_enabled; +}; + +/* PRCMU clock operations. */ + +static int clk_prcmu_prepare(struct clk_hw *hw) +{ +	struct clk_prcmu *clk = to_clk_prcmu(hw); +	return prcmu_request_clock(clk->cg_sel, true); +} + +static void clk_prcmu_unprepare(struct clk_hw *hw) +{ +	struct clk_prcmu *clk = to_clk_prcmu(hw); +	if (prcmu_request_clock(clk->cg_sel, false)) +		pr_err("clk_prcmu: %s failed to disable %s.\n", __func__, +			hw->init->name); +} + +static int clk_prcmu_enable(struct clk_hw *hw) +{ +	struct clk_prcmu *clk = to_clk_prcmu(hw); +	clk->is_enabled = 1; +	return 0; +} + +static void clk_prcmu_disable(struct clk_hw *hw) +{ +	struct clk_prcmu *clk = to_clk_prcmu(hw); +	clk->is_enabled = 0; +} + +static int clk_prcmu_is_enabled(struct clk_hw *hw) +{ +	struct clk_prcmu *clk = to_clk_prcmu(hw); +	return clk->is_enabled; +} + +static unsigned long clk_prcmu_recalc_rate(struct clk_hw *hw, +					   unsigned long parent_rate) +{ +	struct clk_prcmu *clk = to_clk_prcmu(hw); +	return prcmu_clock_rate(clk->cg_sel); +} + +static long clk_prcmu_round_rate(struct clk_hw *hw, unsigned long rate, +				 unsigned long *parent_rate) +{ +	struct clk_prcmu *clk = to_clk_prcmu(hw); +	return prcmu_round_clock_rate(clk->cg_sel, rate); +} + +static int clk_prcmu_set_rate(struct clk_hw *hw, unsigned long rate, +			      unsigned long parent_rate) +{ +	struct clk_prcmu *clk = to_clk_prcmu(hw); +	return prcmu_set_clock_rate(clk->cg_sel, rate); +} + +static int request_ape_opp100(bool enable) +{ +	static int reqs; +	int err = 0; + +	if (enable) { +		if (!reqs) +			err = prcmu_qos_add_requirement(PRCMU_QOS_APE_OPP, +							"clock", 100); +		if (!err) +			reqs++; +	} else { +		reqs--; +		if (!reqs) +			prcmu_qos_remove_requirement(PRCMU_QOS_APE_OPP, +						"clock"); +	} +	return err; +} + +static int clk_prcmu_opp_prepare(struct clk_hw *hw) +{ +	int err; +	struct clk_prcmu *clk = to_clk_prcmu(hw); + +	err = request_ape_opp100(true); +	if (err) { +		pr_err("clk_prcmu: %s failed to request APE OPP100 for %s.\n", +			__func__, hw->init->name); +		return err; +	} + +	err = prcmu_request_clock(clk->cg_sel, true); +	if (err) +		request_ape_opp100(false); + +	return err; +} + +static void clk_prcmu_opp_unprepare(struct clk_hw *hw) +{ +	struct clk_prcmu *clk = to_clk_prcmu(hw); + +	if (prcmu_request_clock(clk->cg_sel, false)) +		goto out_error; +	if (request_ape_opp100(false)) +		goto out_error; +	return; + +out_error: +	pr_err("clk_prcmu: %s failed to disable %s.\n", __func__, +		hw->init->name); +} + +static struct clk_ops clk_prcmu_scalable_ops = { +	.prepare = clk_prcmu_prepare, +	.unprepare = clk_prcmu_unprepare, +	.enable = clk_prcmu_enable, +	.disable = clk_prcmu_disable, +	.is_enabled = clk_prcmu_is_enabled, +	.recalc_rate = clk_prcmu_recalc_rate, +	.round_rate = clk_prcmu_round_rate, +	.set_rate = clk_prcmu_set_rate, +}; + +static struct clk_ops clk_prcmu_gate_ops = { +	.prepare = clk_prcmu_prepare, +	.unprepare = clk_prcmu_unprepare, +	.enable = clk_prcmu_enable, +	.disable = clk_prcmu_disable, +	.is_enabled = clk_prcmu_is_enabled, +	.recalc_rate = clk_prcmu_recalc_rate, +}; + +static struct clk_ops clk_prcmu_rate_ops = { +	.is_enabled = clk_prcmu_is_enabled, +	.recalc_rate = clk_prcmu_recalc_rate, +}; + +static struct clk_ops clk_prcmu_opp_gate_ops = { +	.prepare = clk_prcmu_opp_prepare, +	.unprepare = clk_prcmu_opp_unprepare, +	.enable = clk_prcmu_enable, +	.disable = clk_prcmu_disable, +	.is_enabled = clk_prcmu_is_enabled, +	.recalc_rate = clk_prcmu_recalc_rate, +}; + +static struct clk *clk_reg_prcmu(const char *name, +				 const char *parent_name, +				 u8 cg_sel, +				 unsigned long rate, +				 unsigned long flags, +				 struct clk_ops *clk_prcmu_ops) +{ +	struct clk_prcmu *clk; +	struct clk_init_data clk_prcmu_init; +	struct clk *clk_reg; + +	if (!name) { +		pr_err("clk_prcmu: %s invalid arguments passed\n", __func__); +		return ERR_PTR(-EINVAL); +	} + +	clk = kzalloc(sizeof(struct clk_prcmu), GFP_KERNEL); +	if (!clk) { +		pr_err("clk_prcmu: %s could not allocate clk\n", __func__); +		return ERR_PTR(-ENOMEM); +	} + +	clk->cg_sel = cg_sel; +	clk->is_enabled = 1; +	/* "rate" can be used for changing the initial frequency */ +	if (rate) +		prcmu_set_clock_rate(cg_sel, rate); + +	clk_prcmu_init.name = name; +	clk_prcmu_init.ops = clk_prcmu_ops; +	clk_prcmu_init.flags = flags; +	clk_prcmu_init.parent_names = (parent_name ? &parent_name : NULL); +	clk_prcmu_init.num_parents = (parent_name ? 1 : 0); +	clk->hw.init = &clk_prcmu_init; + +	clk_reg = clk_register(NULL, &clk->hw); +	if (IS_ERR_OR_NULL(clk_reg)) +		goto free_clk; + +	return clk_reg; + +free_clk: +	kfree(clk); +	pr_err("clk_prcmu: %s failed to register clk\n", __func__); +	return ERR_PTR(-ENOMEM); +} + +struct clk *clk_reg_prcmu_scalable(const char *name, +				   const char *parent_name, +				   u8 cg_sel, +				   unsigned long rate, +				   unsigned long flags) +{ +	return clk_reg_prcmu(name, parent_name, cg_sel, rate, flags, +			&clk_prcmu_scalable_ops); +} + +struct clk *clk_reg_prcmu_gate(const char *name, +			       const char *parent_name, +			       u8 cg_sel, +			       unsigned long flags) +{ +	return clk_reg_prcmu(name, parent_name, cg_sel, 0, flags, +			&clk_prcmu_gate_ops); +} + +struct clk *clk_reg_prcmu_rate(const char *name, +			       const char *parent_name, +			       u8 cg_sel, +			       unsigned long flags) +{ +	return clk_reg_prcmu(name, parent_name, cg_sel, 0, flags, +			&clk_prcmu_rate_ops); +} + +struct clk *clk_reg_prcmu_opp_gate(const char *name, +				   const char *parent_name, +				   u8 cg_sel, +				   unsigned long flags) +{ +	return clk_reg_prcmu(name, parent_name, cg_sel, 0, flags, +			&clk_prcmu_opp_gate_ops); +}  |