78 lines
1.8 KiB
C
78 lines
1.8 KiB
C
/*
|
|
* clk-mux.c - generic barebox clock support. Based on Linux clk support
|
|
*
|
|
* Copyright (c) 2012 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License as
|
|
* published by the Free Software Foundation; either version 2 of
|
|
* the License, or (at your option) any later version.
|
|
*
|
|
* 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 <common.h>
|
|
#include <io.h>
|
|
#include <malloc.h>
|
|
#include <linux/clk.h>
|
|
#include <linux/err.h>
|
|
|
|
struct clk_mux {
|
|
struct clk clk;
|
|
void __iomem *reg;
|
|
int shift;
|
|
int width;
|
|
};
|
|
|
|
static int clk_mux_get_parent(struct clk *clk)
|
|
{
|
|
struct clk_mux *m = container_of(clk, struct clk_mux, clk);
|
|
int idx = readl(m->reg) >> m->shift & ((1 << m->width) - 1);
|
|
|
|
return idx;
|
|
}
|
|
|
|
static int clk_mux_set_parent(struct clk *clk, u8 idx)
|
|
{
|
|
struct clk_mux *m = container_of(clk, struct clk_mux, clk);
|
|
u32 val;
|
|
|
|
val = readl(m->reg);
|
|
val &= ~(((1 << m->width) - 1) << m->shift);
|
|
val |= idx << m->shift;
|
|
writel(val, m->reg);
|
|
|
|
return 0;
|
|
}
|
|
|
|
struct clk_ops clk_mux_ops = {
|
|
.get_parent = clk_mux_get_parent,
|
|
.set_parent = clk_mux_set_parent,
|
|
};
|
|
|
|
struct clk *clk_mux(const char *name, void __iomem *reg,
|
|
u8 shift, u8 width, const char **parents, u8 num_parents)
|
|
{
|
|
struct clk_mux *m = xzalloc(sizeof(*m));
|
|
int ret;
|
|
|
|
m->reg = reg;
|
|
m->shift = shift;
|
|
m->width = width;
|
|
m->clk.ops = &clk_mux_ops;
|
|
m->clk.name = name;
|
|
m->clk.parent_names = parents;
|
|
m->clk.num_parents = num_parents;
|
|
|
|
ret = clk_register(&m->clk);
|
|
if (ret) {
|
|
free(m);
|
|
return ERR_PTR(ret);
|
|
}
|
|
|
|
return &m->clk;
|
|
}
|