/*
* Clock management for AT32AP CPUs
*
* Copyright (C) 2006 Atmel Corporation
*
* Based on arch/arm/mach-at91/clock.c
* Copyright (C) 2005 David Brownell
* Copyright (C) 2005 Ivan Kokshaysky
*
* 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.
*/
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/device.h>
#include <linux/string.h>
#include <linux/list.h>
#include <mach/chip.h>
#include "clock.h"
/* at32 clock list */
static LIST_HEAD(at32_clock_list);
static DEFINE_SPINLOCK(clk_lock);
static DEFINE_SPINLOCK(clk_list_lock);
void at32_clk_register(struct clk *clk)
{
spin_lock(&clk_list_lock);
/* add the new item to the end of the list */
list_add_tail(&clk->list, &at32_clock_list);
spin_unlock(&clk_list_lock);
}
struct clk *clk_get(struct device *dev, const char *id)
{
struct clk *clk;
spin_lock(&clk_list_lock);
list_for_each_entry(clk, &at32_clock_list, list) {
if (clk->dev == dev && strcmp(id, clk->name) == 0) {
spin_unlock(&clk_list_lock);
return clk;
}
}
spin_unlock(&clk_list_lock);
return ERR_PTR(-ENOENT);
}
EXPORT_SYMBOL(clk_get);
void clk_put(struct clk *clk)
{
/* clocks are static for now, we can't free them */
}
EXPORT_SYMBOL(clk_put);
static void __clk_enable(struct clk *clk)
{
if (clk->parent)
__clk_enable(clk->parent);
if (clk->users++ == 0 && clk->mode)
clk->mode(clk, 1);
}
int clk_enable(struct clk *clk)
{
unsigned long flags;
spin_lock_irqsave(&clk_lock, flags);
__clk_enable(clk);
spin_unlock_irqrestore(&clk_lock, flags);
return 0;
}
EXPORT_SYMBOL(clk_enable);
static void __clk_disable(struct clk *clk)
{
if (clk->users == 0) {
printk(KERN_ERR "%s: mismatched disable\n", clk->name);
WARN_ON(1);
return;
}
if (--clk->users == 0 && clk->mode)
clk->mode(clk, 0);
if (clk->parent)
__clk_disable(clk->parent);
}
void clk_disable(struct clk *clk)
{
unsigned long flags;
spin_lock_irqsave(&clk_lock, flags);
__clk_disable(clk);
spin_unlock_irqrestore(&clk_lock, flags);
}
EXPORT_SYMBOL(clk_disable);
unsigned long clk_get_rate(struct clk *clk)
{
unsigned long flags;
unsigned long rate;
spin_lock_irqsave(&clk_lock, flags);
rate = clk->get_rate(clk);
spin_unlock_irqrestore(&clk_lock, flags);
return rate;
}
EXPORT_SYMBOL(clk_get_rate);
long clk_round_rate(struct clk *clk, unsigned long rate)
{
unsigned long flags, actual_rate;
if (!clk->set_rate)
return -ENOSYS;
spin_lock_irqsave(&clk_lock, flags);
actual_rate = clk->set_rate(clk, rate, 0);
spin_unlock_irqrestore(&clk_lock, flags);
return actual_rate;
}
EXPORT_SYMBOL(clk_round_rate);
int clk_set_rate(struct clk *clk, unsigned long rate)
{
unsigned long flags;
long ret;
if (!clk->set_rate)
return -ENOSYS;
spin_lock_irqsave(&clk_lock, flags);
ret = clk->set_rate(clk, rate, 1);
spin_unlock_irqrestore(&clk_lock, flags);
return (ret < 0) ? ret : 0;
}
EXPORT_SYMBOL(clk_set_rate);
int clk_set_parent(struct clk *clk, struct clk *parent)
{
unsigned long flags;
int ret;
if (!clk->set_parent)
return -ENOSYS;
spin_lock_irqsave(&clk_lock, flags);
ret = clk->set_parent(clk, parent);
spin_unlock_irqrestore(&clk_lock, flags);
return ret;
}
EXPORT_SYMBOL(clk_set_parent);
struct clk *clk_get_parent(struct clk *clk)
{
return clk->parent;
}
EXPORT_SYMBOL(clk_get_parent);
#ifdef CONFIG_DEBUG_FS
/* /sys/kernel/debug/at32ap_clk */
#include <linux/io.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include "pm.h"
#define NEST_DELTA 2
#define NEST_MAX 6
struct clkinf {
struct seq_file *s;
unsigned nest;
};
static void
dump_clock(struct clk *parent, struct clkinf *r)
{
unsigned nest = r->nest;
char buf[16 + NEST_MAX];
struct clk *clk;
unsigned i;
/* skip clocks coupled to devices that aren't registered */
if (parent->dev && !parent->dev->bus_id[0] && !parent->users)
return;
/* <nest spaces> name <pad to end> */
memset(buf, ' ', sizeof(buf) - 1);
buf[sizeof(buf) - 1] = 0;
i = strlen(parent->name);
memcpy(buf + nest, parent->name,
min(i, (unsigned)(sizeof(buf) - 1 - nest)));
seq_printf(r->s, "%s%c users=%2d %-3s %9ld Hz",
buf, parent->set_parent ? '*' : ' ',
parent->users,
parent->users ? "on" : "off", /* NOTE: not-paranoid!! */
clk_get_rate(parent));
if (parent->dev)
seq_printf(r->s, ", for %s", parent->dev->bus_id);
seq_printf(r->s, "\n");
/* cost of this scan is small, but not linear... */
r->nest = nest + NEST_DELTA;
list_for_each_entry(clk, &at32_clock_list, list) {
if (clk->parent == parent)
dump_clock(clk, r);
}
r->nest = nest;
}
static int clk_show(struct seq_file *s, void *unused)
{
struct clkinf r;
int i;
struct clk *clk;
/* show all the power manager registers */
seq_printf(s, "MCCTRL = %8x\n", pm_readl(MCCTRL));
seq_printf(s, "CKSEL = %8x\n", pm_readl(CKSEL));
seq_printf(s, "CPUMASK = %8x\n", pm_readl(CPU_MASK));
seq_printf(s, "HSBMASK = %8x\n", pm_readl(HSB_MASK));
seq_printf(s, "PBAMASK = %8x\n", pm_readl(PBA_MASK));
seq_printf(s, "PBBMASK = %8x\n", pm_readl(PBB_MASK));
seq_printf(s, "PLL0 = %8x\n", pm_readl(PLL0));
seq_printf(s, "PLL1 = %8x\n", pm_readl(PLL1));
seq_printf(s, "IMR = %8x\n", pm_readl(IMR));
for (i = 0; i < 8; i++) {
if (i == 5)
continue;
seq_printf(s, "GCCTRL%d = %8x\n", i, pm_readl(GCCTRL(i)));
}
seq_printf(s, "\n");
r.s = s;
r.nest = 0;
/* protected from changes on the list while dumping */
spin_lock(&clk_list_lock);
/* show clock tree as derived from the three oscillators */
clk = clk_get(NULL, "osc32k");
dump_clock(clk, &r);
clk_put(clk);
clk = clk_get(NULL, "osc0");
dump_clock(clk, &r);
clk_put(clk);
clk = clk_get(NULL, "osc1");
dump_clock(clk, &r);
clk_put(clk);
spin_unlock(&clk_list_lock);
return 0;
}
static int clk_open(struct inode *inode, struct file *file)
{
return single_open(file, clk_show, NULL);
}
static const struct file_operations clk_operations = {
.open = clk_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int __init clk_debugfs_init(void)
{
(void) debugfs_create_file("at32ap_clk", S_IFREG | S_IRUGO,
NULL, NULL, &clk_operations);
return 0;
}
postcore_initcall(clk_debugfs_init);
#endif
