Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/*

 * 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 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 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)

{

        struct proc_dir_entry *entry;

        entry = create_proc_entry("davinci_clocks", 0, NULL);

        if (entry)

                entry->proc_fops = &proc_davinci_ck_operations;

        return 0;

}

__initcall(davinci_ck_proc_init);

#endif  /* CONFIG_DEBUG_PROC_FS */