linux/drivers/clk/clk-ppc-corenet.c

282 lines
6.5 KiB
C

/*
* Copyright 2013 Freescale Semiconductor, Inc.
*
* 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.
*
* clock driver for Freescale PowerPC corenet SoCs.
*/
#include <linux/clk-provider.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <linux/of.h>
#include <linux/slab.h>
struct cmux_clk {
struct clk_hw hw;
void __iomem *reg;
u32 flags;
};
#define PLL_KILL BIT(31)
#define CLKSEL_SHIFT 27
#define CLKSEL_ADJUST BIT(0)
#define to_cmux_clk(p) container_of(p, struct cmux_clk, hw)
static void __iomem *base;
static unsigned int clocks_per_pll;
static int cmux_set_parent(struct clk_hw *hw, u8 idx)
{
struct cmux_clk *clk = to_cmux_clk(hw);
u32 clksel;
clksel = ((idx / clocks_per_pll) << 2) + idx % clocks_per_pll;
if (clk->flags & CLKSEL_ADJUST)
clksel += 8;
clksel = (clksel & 0xf) << CLKSEL_SHIFT;
iowrite32be(clksel, clk->reg);
return 0;
}
static u8 cmux_get_parent(struct clk_hw *hw)
{
struct cmux_clk *clk = to_cmux_clk(hw);
u32 clksel;
clksel = ioread32be(clk->reg);
clksel = (clksel >> CLKSEL_SHIFT) & 0xf;
if (clk->flags & CLKSEL_ADJUST)
clksel -= 8;
clksel = (clksel >> 2) * clocks_per_pll + clksel % 4;
return clksel;
}
const struct clk_ops cmux_ops = {
.get_parent = cmux_get_parent,
.set_parent = cmux_set_parent,
};
static void __init core_mux_init(struct device_node *np)
{
struct clk *clk;
struct clk_init_data init;
struct cmux_clk *cmux_clk;
struct device_node *node;
int rc, count, i;
u32 offset;
const char *clk_name;
const char **parent_names;
rc = of_property_read_u32(np, "reg", &offset);
if (rc) {
pr_err("%s: could not get reg property\n", np->name);
return;
}
/* get the input clock source count */
count = of_property_count_strings(np, "clock-names");
if (count < 0) {
pr_err("%s: get clock count error\n", np->name);
return;
}
parent_names = kzalloc((sizeof(char *) * count), GFP_KERNEL);
if (!parent_names) {
pr_err("%s: could not allocate parent_names\n", __func__);
return;
}
for (i = 0; i < count; i++)
parent_names[i] = of_clk_get_parent_name(np, i);
cmux_clk = kzalloc(sizeof(struct cmux_clk), GFP_KERNEL);
if (!cmux_clk) {
pr_err("%s: could not allocate cmux_clk\n", __func__);
goto err_name;
}
cmux_clk->reg = base + offset;
node = of_find_compatible_node(NULL, NULL, "fsl,p4080-clockgen");
if (node && (offset >= 0x80))
cmux_clk->flags = CLKSEL_ADJUST;
rc = of_property_read_string_index(np, "clock-output-names",
0, &clk_name);
if (rc) {
pr_err("%s: read clock names error\n", np->name);
goto err_clk;
}
init.name = clk_name;
init.ops = &cmux_ops;
init.parent_names = parent_names;
init.num_parents = count;
init.flags = 0;
cmux_clk->hw.init = &init;
clk = clk_register(NULL, &cmux_clk->hw);
if (IS_ERR(clk)) {
pr_err("%s: could not register clock\n", clk_name);
goto err_clk;
}
rc = of_clk_add_provider(np, of_clk_src_simple_get, clk);
if (rc) {
pr_err("Could not register clock provider for node:%s\n",
np->name);
goto err_clk;
}
goto err_name;
err_clk:
kfree(cmux_clk);
err_name:
/* free *_names because they are reallocated when registered */
kfree(parent_names);
}
static void __init core_pll_init(struct device_node *np)
{
u32 offset, mult;
int i, rc, count;
const char *clk_name, *parent_name;
struct clk_onecell_data *onecell_data;
struct clk **subclks;
rc = of_property_read_u32(np, "reg", &offset);
if (rc) {
pr_err("%s: could not get reg property\n", np->name);
return;
}
/* get the multiple of PLL */
mult = ioread32be(base + offset);
/* check if this PLL is disabled */
if (mult & PLL_KILL) {
pr_debug("PLL:%s is disabled\n", np->name);
return;
}
mult = (mult >> 1) & 0x3f;
parent_name = of_clk_get_parent_name(np, 0);
if (!parent_name) {
pr_err("PLL: %s must have a parent\n", np->name);
return;
}
count = of_property_count_strings(np, "clock-output-names");
if (count < 0 || count > 4) {
pr_err("%s: clock is not supported\n", np->name);
return;
}
/* output clock number per PLL */
clocks_per_pll = count;
subclks = kzalloc(sizeof(struct clk *) * count, GFP_KERNEL);
if (!subclks) {
pr_err("%s: could not allocate subclks\n", __func__);
return;
}
onecell_data = kzalloc(sizeof(struct clk_onecell_data), GFP_KERNEL);
if (!onecell_data) {
pr_err("%s: could not allocate onecell_data\n", __func__);
goto err_clks;
}
for (i = 0; i < count; i++) {
rc = of_property_read_string_index(np, "clock-output-names",
i, &clk_name);
if (rc) {
pr_err("%s: could not get clock names\n", np->name);
goto err_cell;
}
/*
* when count == 4, there are 4 output clocks:
* /1, /2, /3, /4 respectively
* when count < 4, there are at least 2 output clocks:
* /1, /2, (/4, if count == 3) respectively.
*/
if (count == 4)
subclks[i] = clk_register_fixed_factor(NULL, clk_name,
parent_name, 0, mult, 1 + i);
else
subclks[i] = clk_register_fixed_factor(NULL, clk_name,
parent_name, 0, mult, 1 << i);
if (IS_ERR(subclks[i])) {
pr_err("%s: could not register clock\n", clk_name);
goto err_cell;
}
}
onecell_data->clks = subclks;
onecell_data->clk_num = count;
rc = of_clk_add_provider(np, of_clk_src_onecell_get, onecell_data);
if (rc) {
pr_err("Could not register clk provider for node:%s\n",
np->name);
goto err_cell;
}
return;
err_cell:
kfree(onecell_data);
err_clks:
kfree(subclks);
}
static const struct of_device_id clk_match[] __initconst = {
{ .compatible = "fixed-clock", .data = of_fixed_clk_setup, },
{ .compatible = "fsl,core-pll-clock", .data = core_pll_init, },
{ .compatible = "fsl,core-mux-clock", .data = core_mux_init, },
{}
};
static int __init ppc_corenet_clk_probe(struct platform_device *pdev)
{
struct device_node *np;
np = pdev->dev.of_node;
base = of_iomap(np, 0);
if (!base) {
dev_err(&pdev->dev, "iomap error\n");
return -ENOMEM;
}
of_clk_init(clk_match);
return 0;
}
static const struct of_device_id ppc_clk_ids[] __initconst = {
{ .compatible = "fsl,qoriq-clockgen-1.0", },
{ .compatible = "fsl,qoriq-clockgen-2.0", },
{}
};
static struct platform_driver ppc_corenet_clk_driver = {
.driver = {
.name = "ppc_corenet_clock",
.owner = THIS_MODULE,
.of_match_table = ppc_clk_ids,
},
.probe = ppc_corenet_clk_probe,
};
static int __init ppc_corenet_clk_init(void)
{
return platform_driver_register(&ppc_corenet_clk_driver);
}
subsys_initcall(ppc_corenet_clk_init);