linux/drivers/clk/ux500/clk-prcc.c

161 lines
3.5 KiB
C

/*
* PRCC 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/slab.h>
#include <linux/io.h>
#include <linux/err.h>
#include <linux/types.h>
#include "clk.h"
#define PRCC_PCKEN 0x000
#define PRCC_PCKDIS 0x004
#define PRCC_KCKEN 0x008
#define PRCC_KCKDIS 0x00C
#define PRCC_PCKSR 0x010
#define PRCC_KCKSR 0x014
#define to_clk_prcc(_hw) container_of(_hw, struct clk_prcc, hw)
struct clk_prcc {
struct clk_hw hw;
void __iomem *base;
u32 cg_sel;
int is_enabled;
};
/* PRCC clock operations. */
static int clk_prcc_pclk_enable(struct clk_hw *hw)
{
struct clk_prcc *clk = to_clk_prcc(hw);
writel(clk->cg_sel, (clk->base + PRCC_PCKEN));
while (!(readl(clk->base + PRCC_PCKSR) & clk->cg_sel))
cpu_relax();
clk->is_enabled = 1;
return 0;
}
static void clk_prcc_pclk_disable(struct clk_hw *hw)
{
struct clk_prcc *clk = to_clk_prcc(hw);
writel(clk->cg_sel, (clk->base + PRCC_PCKDIS));
clk->is_enabled = 0;
}
static int clk_prcc_kclk_enable(struct clk_hw *hw)
{
struct clk_prcc *clk = to_clk_prcc(hw);
writel(clk->cg_sel, (clk->base + PRCC_KCKEN));
while (!(readl(clk->base + PRCC_KCKSR) & clk->cg_sel))
cpu_relax();
clk->is_enabled = 1;
return 0;
}
static void clk_prcc_kclk_disable(struct clk_hw *hw)
{
struct clk_prcc *clk = to_clk_prcc(hw);
writel(clk->cg_sel, (clk->base + PRCC_KCKDIS));
clk->is_enabled = 0;
}
static int clk_prcc_is_enabled(struct clk_hw *hw)
{
struct clk_prcc *clk = to_clk_prcc(hw);
return clk->is_enabled;
}
static const struct clk_ops clk_prcc_pclk_ops = {
.enable = clk_prcc_pclk_enable,
.disable = clk_prcc_pclk_disable,
.is_enabled = clk_prcc_is_enabled,
};
static const struct clk_ops clk_prcc_kclk_ops = {
.enable = clk_prcc_kclk_enable,
.disable = clk_prcc_kclk_disable,
.is_enabled = clk_prcc_is_enabled,
};
static struct clk *clk_reg_prcc(const char *name,
const char *parent_name,
resource_size_t phy_base,
u32 cg_sel,
unsigned long flags,
const struct clk_ops *clk_prcc_ops)
{
struct clk_prcc *clk;
struct clk_init_data clk_prcc_init;
struct clk *clk_reg;
if (!name) {
pr_err("clk_prcc: %s invalid arguments passed\n", __func__);
return ERR_PTR(-EINVAL);
}
clk = kzalloc(sizeof(*clk), GFP_KERNEL);
if (!clk)
return ERR_PTR(-ENOMEM);
clk->base = ioremap(phy_base, SZ_4K);
if (!clk->base)
goto free_clk;
clk->cg_sel = cg_sel;
clk->is_enabled = 1;
clk_prcc_init.name = name;
clk_prcc_init.ops = clk_prcc_ops;
clk_prcc_init.flags = flags;
clk_prcc_init.parent_names = (parent_name ? &parent_name : NULL);
clk_prcc_init.num_parents = (parent_name ? 1 : 0);
clk->hw.init = &clk_prcc_init;
clk_reg = clk_register(NULL, &clk->hw);
if (IS_ERR_OR_NULL(clk_reg))
goto unmap_clk;
return clk_reg;
unmap_clk:
iounmap(clk->base);
free_clk:
kfree(clk);
pr_err("clk_prcc: %s failed to register clk\n", __func__);
return ERR_PTR(-ENOMEM);
}
struct clk *clk_reg_prcc_pclk(const char *name,
const char *parent_name,
resource_size_t phy_base,
u32 cg_sel,
unsigned long flags)
{
return clk_reg_prcc(name, parent_name, phy_base, cg_sel, flags,
&clk_prcc_pclk_ops);
}
struct clk *clk_reg_prcc_kclk(const char *name,
const char *parent_name,
resource_size_t phy_base,
u32 cg_sel,
unsigned long flags)
{
return clk_reg_prcc(name, parent_name, phy_base, cg_sel, flags,
&clk_prcc_kclk_ops);
}