/*
* Copyright (c) 2014 MundoReader S.L.
* Author: Heiko Stuebner <heiko@sntech.de>
*
* based on
*
* samsung/clk.c
* Copyright (c) 2013 Samsung Electronics Co., Ltd.
* Copyright (c) 2013 Linaro Ltd.
* Author: Thomas Abraham <thomas.ab@samsung.com>
*
* 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 <linux/slab.h>
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include "clk.h"
/**
* Register a clock branch.
* Most clock branches have a form like
*
* src1 --|--\
* |M |--[GATE]-[DIV]-
* src2 --|--/
*
* sometimes without one of those components.
*/
struct clk *rockchip_clk_register_branch(const char *name,
const char **parent_names, u8 num_parents, void __iomem *base,
int muxdiv_offset, u8 mux_shift, u8 mux_width, u8 mux_flags,
u8 div_shift, u8 div_width, u8 div_flags,
struct clk_div_table *div_table, int gate_offset,
u8 gate_shift, u8 gate_flags, unsigned long flags,
spinlock_t *lock)
{
struct clk *clk;
struct clk_mux *mux = NULL;
struct clk_gate *gate = NULL;
struct clk_divider *div = NULL;
const struct clk_ops *mux_ops = NULL, *div_ops = NULL,
*gate_ops = NULL;
if (num_parents > 1) {
mux = kzalloc(sizeof(*mux), GFP_KERNEL);
if (!mux)
return ERR_PTR(-ENOMEM);
mux->reg = base + muxdiv_offset;
mux->shift = mux_shift;
mux->mask = BIT(mux_width) - 1;
mux->flags = mux_flags;
mux->lock = lock;
mux_ops = (mux_flags & CLK_MUX_READ_ONLY) ? &clk_mux_ro_ops
: &clk_mux_ops;
}
if (gate_offset >= 0) {
gate = kzalloc(sizeof(*gate), GFP_KERNEL);
if (!gate)
return ERR_PTR(-ENOMEM);
gate->flags = gate_flags;
gate->reg = base + gate_offset;
gate->bit_idx = gate_shift;
gate->lock = lock;
gate_ops = &clk_gate_ops;
}
if (div_width > 0) {
div = kzalloc(sizeof(*div), GFP_KERNEL);
if (!div)
return ERR_PTR(-ENOMEM);
div->flags = div_flags;
div->reg = base + muxdiv_offset;
div->shift = div_shift;
div->width = div_width;
div->lock = lock;
div->table = div_table;
div_ops = (div_flags & CLK_DIVIDER_READ_ONLY)
? &clk_divider_ro_ops
: &clk_divider_ops;
}
clk = clk_register_composite(NULL, name, parent_names, num_parents,
mux ? &mux->hw : NULL, mux_ops,
div ? &div->hw : NULL, div_ops,
gate ? &gate->hw : NULL, gate_ops,
flags);
return clk;
}
static DEFINE_SPINLOCK(clk_lock);
static struct clk **clk_table;
static void __iomem *reg_base;
static struct clk_onecell_data clk_data;
void __init rockchip_clk_init(struct device_node *np, void __iomem *base,
unsigned long nr_clks)
{
reg_base = base;
clk_table = kcalloc(nr_clks, sizeof(struct clk *), GFP_KERNEL);
if (!clk_table)
pr_err("%s: could not allocate clock lookup table\n", __func__);
clk_data.clks = clk_table;
clk_data.clk_num = nr_clks;
of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data);
}
void rockchip_clk_add_lookup(struct clk *clk, unsigned int id)
{
if (clk_table && id)
clk_table[id] = clk;
}
void __init rockchip_clk_register_branches(
struct rockchip_clk_branch *list,
unsigned int nr_clk)
{
struct clk *clk = NULL;
unsigned int idx;
unsigned long flags;
for (idx = 0; idx < nr_clk; idx++, list++) {
flags = list->flags;
/* catch simple muxes */
switch (list->branch_type) {
case branch_mux:
clk = clk_register_mux(NULL, list->name,
list->parent_names, list->num_parents,
flags, reg_base + list->muxdiv_offset,
list->mux_shift, list->mux_width,
list->mux_flags, &clk_lock);
break;
case branch_divider:
if (list->div_table)
clk = clk_register_divider_table(NULL,
list->name, list->parent_names[0],
flags, reg_base + list->muxdiv_offset,
list->div_shift, list->div_width,
list->div_flags, list->div_table,
&clk_lock);
else
clk = clk_register_divider(NULL, list->name,
list->parent_names[0], flags,
reg_base + list->muxdiv_offset,
list->div_shift, list->div_width,
list->div_flags, &clk_lock);
break;
case branch_fraction_divider:
/* unimplemented */
continue;
break;
case branch_gate:
flags |= CLK_SET_RATE_PARENT;
/* keep all gates untouched for now */
flags |= CLK_IGNORE_UNUSED;
clk = clk_register_gate(NULL, list->name,
list->parent_names[0], flags,
reg_base + list->gate_offset,
list->gate_shift, list->gate_flags, &clk_lock);
break;
case branch_composite:
/* keep all gates untouched for now */
flags |= CLK_IGNORE_UNUSED;
clk = rockchip_clk_register_branch(list->name,
list->parent_names, list->num_parents,
reg_base, list->muxdiv_offset, list->mux_shift,
list->mux_width, list->mux_flags,
list->div_shift, list->div_width,
list->div_flags, list->div_table,
list->gate_offset, list->gate_shift,
list->gate_flags, flags, &clk_lock);
break;
}
/* none of the cases above matched */
if (!clk) {
pr_err("%s: unknown clock type %d\n",
__func__, list->branch_type);
continue;
}
if (IS_ERR(clk)) {
pr_err("%s: failed to register clock %s: %ld\n",
__func__, list->name, PTR_ERR(clk));
continue;
}
rockchip_clk_add_lookup(clk, list->id);
}
}
