blob: 930cdfeb47ab451659843446b3f8ebdcdee01776 [file] [log] [blame]
/*
* 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);
}