/*
* TI DaVinci clock config file
*
* Copyright (C) 2006 Texas Instruments.
*
* 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.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <asm/hardware.h>
#include <asm/io.h>
#include <asm/arch/psc.h>
#include "clock.h"
/* PLL/Reset register offsets */
#define PLLM 0x110
static LIST_HEAD(clocks);
static DEFINE_MUTEX(clocks_mutex);
static DEFINE_SPINLOCK(clockfw_lock);
static unsigned int commonrate;
static unsigned int armrate;
static unsigned int fixedrate = 27000000; /* 27 MHZ */
extern void davinci_psc_config(unsigned int domain, unsigned int id, char enable);
/*
* Returns a clock. Note that we first try to use device id on the bus
* and clock name. If this fails, we try to use clock name only.
*/
struct clk *clk_get(struct device *dev, const char *id)
{
struct clk *p, *clk = ERR_PTR(-ENOENT);
int idno;
if (dev == NULL || dev->bus != &platform_bus_type)
idno = -1;
else
idno = to_platform_device(dev)->id;
mutex_lock(&clocks_mutex);
list_for_each_entry(p, &clocks, node) {
if (p->id == idno &&
strcmp(id, p->name) == 0 && try_module_get(p->owner)) {
clk = p;
goto found;
}
}
list_for_each_entry(p, &clocks, node) {
if (strcmp(id, p->name) == 0 && try_module_get(p->owner)) {
clk = p;
break;
}
}
found:
mutex_unlock(&clocks_mutex);
return clk;
}
EXPORT_SYMBOL(clk_get);
void clk_put(struct clk *clk)
{
if (clk && !IS_ERR(clk))
module_put(clk->owner);
}
EXPORT_SYMBOL(clk_put);
static int __clk_enable(struct clk *clk)
{
if (clk->flags & ALWAYS_ENABLED)
return 0;
davinci_psc_config(DAVINCI_GPSC_ARMDOMAIN, clk->lpsc, 1);
return 0;
}
static void __clk_disable(struct clk *clk)
{
if (clk->usecount)
return;
davinci_psc_config(DAVINCI_GPSC_ARMDOMAIN, clk->lpsc, 0);
}
int clk_enable(struct clk *clk)
{
unsigned long flags;
int ret = 0;
if (clk == NULL || IS_ERR(clk))
return -EINVAL;
if (clk->usecount++ == 0) {
spin_lock_irqsave(&clockfw_lock, flags);
ret = __clk_enable(clk);
spin_unlock_irqrestore(&clockfw_lock, flags);
}
return ret;
}
EXPORT_SYMBOL(clk_enable);
void clk_disable(struct clk *clk)
{
unsigned long flags;
if (clk == NULL || IS_ERR(clk))
return;
if (clk->usecount > 0 && !(--clk->usecount)) {
spin_lock_irqsave(&clockfw_lock, flags);
__clk_disable(clk);
spin_unlock_irqrestore(&clockfw_lock, flags);
}
}
EXPORT_SYMBOL(clk_disable);
unsigned long clk_get_rate(struct clk *clk)
{
if (clk == NULL || IS_ERR(clk))
return -EINVAL;
return *(clk->rate);
}
EXPORT_SYMBOL(clk_get_rate);
long clk_round_rate(struct clk *clk, unsigned long rate)
{
if (clk == NULL || IS_ERR(clk))
return -EINVAL;
return *(clk->rate);
}
EXPORT_SYMBOL(clk_round_rate);
int clk_set_rate(struct clk *clk, unsigned long rate)
{
if (clk == NULL || IS_ERR(clk))
return -EINVAL;
/* changing the clk rate is not supported */
return -EINVAL;
}
EXPORT_SYMBOL(clk_set_rate);
int clk_register(struct clk *clk)
{
if (clk == NULL || IS_ERR(clk))
return -EINVAL;
mutex_lock(&clocks_mutex);
list_add(&clk->node, &clocks);
mutex_unlock(&clocks_mutex);
return 0;
}
EXPORT_SYMBOL(clk_register);
void clk_unregister(struct clk *clk)
{
if (clk == NULL || IS_ERR(clk))
return;
mutex_lock(&clocks_mutex);
list_del(&clk->node);
mutex_unlock(&clocks_mutex);
}
EXPORT_SYMBOL(clk_unregister);
static struct clk davinci_clks[] = {
{
.name = "ARMCLK",
.rate = &armrate,
.lpsc = -1,
.flags = ALWAYS_ENABLED,
},
{
.name = "UART",
.rate = &fixedrate,
.lpsc = DAVINCI_LPSC_UART0,
},
{
.name = "EMACCLK",
.rate = &commonrate,
.lpsc = DAVINCI_LPSC_EMAC_WRAPPER,
},
{
.name = "I2CCLK",
.rate = &fixedrate,
.lpsc = DAVINCI_LPSC_I2C,
},
{
.name = "IDECLK",
.rate = &commonrate,
.lpsc = DAVINCI_LPSC_ATA,
},
{
.name = "McBSPCLK",
.rate = &commonrate,
.lpsc = DAVINCI_LPSC_McBSP,
},
{
.name = "MMCSDCLK",
.rate = &commonrate,
.lpsc = DAVINCI_LPSC_MMC_SD,
},
{
.name = "SPICLK",
.rate = &commonrate,
.lpsc = DAVINCI_LPSC_SPI,
},
{
.name = "gpio",
.rate = &commonrate,
.lpsc = DAVINCI_LPSC_GPIO,
},
{
.name = "AEMIFCLK",
.rate = &commonrate,
.lpsc = DAVINCI_LPSC_AEMIF,
.usecount = 1,
}
};
int __init davinci_clk_init(void)
{
struct clk *clkp;
int count = 0;
u32 pll_mult;
pll_mult = davinci_readl(DAVINCI_PLL_CNTRL0_BASE + PLLM);
commonrate = ((pll_mult + 1) * 27000000) / 6;
armrate = ((pll_mult + 1) * 27000000) / 2;
for (clkp = davinci_clks; count < ARRAY_SIZE(davinci_clks);
count++, clkp++) {
clk_register(clkp);
/* Turn on clocks that have been enabled in the
* table above */
if (clkp->usecount)
clk_enable(clkp);
}
return 0;
}
#ifdef CONFIG_PROC_FS
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
static void *davinci_ck_start(struct seq_file *m, loff_t *pos)
{
return *pos < 1 ? (void *)1 : NULL;
}
static void *davinci_ck_next(struct seq_file *m, void *v, loff_t *pos)
{
++*pos;
return NULL;
}
static void davinci_ck_stop(struct seq_file *m, void *v)
{
}
static int davinci_ck_show(struct seq_file *m, void *v)
{
struct clk *cp;
list_for_each_entry(cp, &clocks, node)
seq_printf(m,"%s %d %d\n", cp->name, *(cp->rate), cp->usecount);
return 0;
}
static const struct seq_operations davinci_ck_op = {
.start = davinci_ck_start,
.next = davinci_ck_next,
.stop = davinci_ck_stop,
.show = davinci_ck_show
};
static int davinci_ck_open(struct inode *inode, struct file *file)
{
return seq_open(file, &davinci_ck_op);
}
static const struct file_operations proc_davinci_ck_operations = {
.open = davinci_ck_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
static int __init davinci_ck_proc_init(void)
{
proc_create("davinci_clocks", 0, NULL, &proc_davinci_ck_operations);
return 0;
}
__initcall(davinci_ck_proc_init);
#endif /* CONFIG_DEBUG_PROC_FS */
