linux/drivers/clk/ti/clk.c

168 lines
4.3 KiB
C

/*
* TI clock support
*
* Copyright (C) 2013 Texas Instruments, Inc.
*
* Tero Kristo <t-kristo@ti.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed "as is" WITHOUT ANY WARRANTY of any
* kind, whether express or implied; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/clk-provider.h>
#include <linux/clkdev.h>
#include <linux/clk/ti.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/list.h>
#undef pr_fmt
#define pr_fmt(fmt) "%s: " fmt, __func__
static int ti_dt_clk_memmap_index;
struct ti_clk_ll_ops *ti_clk_ll_ops;
/**
* ti_dt_clocks_register - register DT alias clocks during boot
* @oclks: list of clocks to register
*
* Register alias or non-standard DT clock entries during boot. By
* default, DT clocks are found based on their node name. If any
* additional con-id / dev-id -> clock mapping is required, use this
* function to list these.
*/
void __init ti_dt_clocks_register(struct ti_dt_clk oclks[])
{
struct ti_dt_clk *c;
struct device_node *node;
struct clk *clk;
struct of_phandle_args clkspec;
for (c = oclks; c->node_name != NULL; c++) {
node = of_find_node_by_name(NULL, c->node_name);
clkspec.np = node;
clk = of_clk_get_from_provider(&clkspec);
if (!IS_ERR(clk)) {
c->lk.clk = clk;
clkdev_add(&c->lk);
} else {
pr_warn("failed to lookup clock node %s\n",
c->node_name);
}
}
}
struct clk_init_item {
struct device_node *node;
struct clk_hw *hw;
ti_of_clk_init_cb_t func;
struct list_head link;
};
static LIST_HEAD(retry_list);
/**
* ti_clk_retry_init - retries a failed clock init at later phase
* @node: device not for the clock
* @hw: partially initialized clk_hw struct for the clock
* @func: init function to be called for the clock
*
* Adds a failed clock init to the retry list. The retry list is parsed
* once all the other clocks have been initialized.
*/
int __init ti_clk_retry_init(struct device_node *node, struct clk_hw *hw,
ti_of_clk_init_cb_t func)
{
struct clk_init_item *retry;
pr_debug("%s: adding to retry list...\n", node->name);
retry = kzalloc(sizeof(*retry), GFP_KERNEL);
if (!retry)
return -ENOMEM;
retry->node = node;
retry->func = func;
retry->hw = hw;
list_add(&retry->link, &retry_list);
return 0;
}
/**
* ti_clk_get_reg_addr - get register address for a clock register
* @node: device node for the clock
* @index: register index from the clock node
*
* Builds clock register address from device tree information. This
* is a struct of type clk_omap_reg.
*/
void __iomem *ti_clk_get_reg_addr(struct device_node *node, int index)
{
struct clk_omap_reg *reg;
u32 val;
u32 tmp;
reg = (struct clk_omap_reg *)&tmp;
reg->index = ti_dt_clk_memmap_index;
if (of_property_read_u32_index(node, "reg", index, &val)) {
pr_err("%s must have reg[%d]!\n", node->name, index);
return NULL;
}
reg->offset = val;
return (void __iomem *)tmp;
}
/**
* ti_dt_clk_init_provider - init master clock provider
* @parent: master node
* @index: internal index for clk_reg_ops
*
* Initializes a master clock IP block and its child clock nodes.
* Regmap is provided for accessing the register space for the
* IP block and all the clocks under it.
*/
void ti_dt_clk_init_provider(struct device_node *parent, int index)
{
const struct of_device_id *match;
struct device_node *np;
struct device_node *clocks;
of_clk_init_cb_t clk_init_cb;
struct clk_init_item *retry;
struct clk_init_item *tmp;
ti_dt_clk_memmap_index = index;
/* get clocks for this parent */
clocks = of_get_child_by_name(parent, "clocks");
if (!clocks) {
pr_err("%s missing 'clocks' child node.\n", parent->name);
return;
}
for_each_child_of_node(clocks, np) {
match = of_match_node(&__clk_of_table, np);
if (!match)
continue;
clk_init_cb = (of_clk_init_cb_t)match->data;
pr_debug("%s: initializing: %s\n", __func__, np->name);
clk_init_cb(np);
}
list_for_each_entry_safe(retry, tmp, &retry_list, link) {
pr_debug("retry-init: %s\n", retry->node->name);
retry->func(retry->hw, retry->node);
list_del(&retry->link);
kfree(retry);
}
}