linux/arch/arm/mach-sa1100/clock.c
Russell King 0920ca103f ARM: sa1100: provide infrastructure to support generic CF sockets
Provide the SoC-level infrastructure to support the generic CF sockets.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-03-24 14:17:06 +00:00

178 lines
3.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* linux/arch/arm/mach-sa1100/clock.c
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/list.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/string.h>
#include <linux/clk.h>
#include <linux/spinlock.h>
#include <linux/mutex.h>
#include <linux/io.h>
#include <linux/clkdev.h>
#include <mach/hardware.h>
#include <mach/generic.h>
struct clkops {
void (*enable)(struct clk *);
void (*disable)(struct clk *);
unsigned long (*get_rate)(struct clk *);
};
struct clk {
const struct clkops *ops;
unsigned int enabled;
};
#define DEFINE_CLK(_name, _ops) \
struct clk clk_##_name = { \
.ops = _ops, \
}
static DEFINE_SPINLOCK(clocks_lock);
/* Dummy clk routine to build generic kernel parts that may be using them */
long clk_round_rate(struct clk *clk, unsigned long rate)
{
return clk_get_rate(clk);
}
EXPORT_SYMBOL(clk_round_rate);
int clk_set_rate(struct clk *clk, unsigned long rate)
{
return 0;
}
EXPORT_SYMBOL(clk_set_rate);
int clk_set_parent(struct clk *clk, struct clk *parent)
{
return 0;
}
EXPORT_SYMBOL(clk_set_parent);
struct clk *clk_get_parent(struct clk *clk)
{
return NULL;
}
EXPORT_SYMBOL(clk_get_parent);
static void clk_gpio27_enable(struct clk *clk)
{
/*
* First, set up the 3.6864MHz clock on GPIO 27 for the SA-1111:
* (SA-1110 Developer's Manual, section 9.1.2.1)
*/
GAFR |= GPIO_32_768kHz;
GPDR |= GPIO_32_768kHz;
TUCR = TUCR_3_6864MHz;
}
static void clk_gpio27_disable(struct clk *clk)
{
TUCR = 0;
GPDR &= ~GPIO_32_768kHz;
GAFR &= ~GPIO_32_768kHz;
}
static void clk_cpu_enable(struct clk *clk)
{
}
static void clk_cpu_disable(struct clk *clk)
{
}
static unsigned long clk_cpu_get_rate(struct clk *clk)
{
return sa11x0_getspeed(0) * 1000;
}
int clk_enable(struct clk *clk)
{
unsigned long flags;
if (clk) {
spin_lock_irqsave(&clocks_lock, flags);
if (clk->enabled++ == 0)
clk->ops->enable(clk);
spin_unlock_irqrestore(&clocks_lock, flags);
}
return 0;
}
EXPORT_SYMBOL(clk_enable);
void clk_disable(struct clk *clk)
{
unsigned long flags;
if (clk) {
WARN_ON(clk->enabled == 0);
spin_lock_irqsave(&clocks_lock, flags);
if (--clk->enabled == 0)
clk->ops->disable(clk);
spin_unlock_irqrestore(&clocks_lock, flags);
}
}
EXPORT_SYMBOL(clk_disable);
unsigned long clk_get_rate(struct clk *clk)
{
if (clk && clk->ops && clk->ops->get_rate)
return clk->ops->get_rate(clk);
return 0;
}
EXPORT_SYMBOL(clk_get_rate);
const struct clkops clk_gpio27_ops = {
.enable = clk_gpio27_enable,
.disable = clk_gpio27_disable,
};
const struct clkops clk_cpu_ops = {
.enable = clk_cpu_enable,
.disable = clk_cpu_disable,
.get_rate = clk_cpu_get_rate,
};
static DEFINE_CLK(gpio27, &clk_gpio27_ops);
static DEFINE_CLK(cpu, &clk_cpu_ops);
static unsigned long clk_36864_get_rate(struct clk *clk)
{
return 3686400;
}
static struct clkops clk_36864_ops = {
.enable = clk_cpu_enable,
.disable = clk_cpu_disable,
.get_rate = clk_36864_get_rate,
};
static DEFINE_CLK(36864, &clk_36864_ops);
static struct clk_lookup sa11xx_clkregs[] = {
CLKDEV_INIT("sa1111.0", NULL, &clk_gpio27),
CLKDEV_INIT("sa1100-rtc", NULL, NULL),
CLKDEV_INIT("sa11x0-fb", NULL, &clk_cpu),
CLKDEV_INIT("sa11x0-pcmcia", NULL, &clk_cpu),
CLKDEV_INIT("sa11x0-pcmcia.0", NULL, &clk_cpu),
CLKDEV_INIT("sa11x0-pcmcia.1", NULL, &clk_cpu),
/* sa1111 names devices using internal offsets, PCMCIA is at 0x1800 */
CLKDEV_INIT("1800", NULL, &clk_cpu),
CLKDEV_INIT(NULL, "OSTIMER0", &clk_36864),
};
int __init sa11xx_clk_init(void)
{
clkdev_add_table(sa11xx_clkregs, ARRAY_SIZE(sa11xx_clkregs));
return 0;
}