alistair23-linux/arch/mips/loongson/lemote-2f/clock.c
Viresh Kumar 7f4b04614a cpufreq: create another field .flags in cpufreq_frequency_table
Currently cpufreq frequency table has two fields: frequency and driver_data.
driver_data is only for drivers' internal use and cpufreq core shouldn't use
it at all. But with the introduction of BOOST frequencies, this assumption
was broken and we started using it as a flag instead.

There are two problems due to this:
- It is against the description of this field, as driver's data is used by
  the core now.
- if drivers fill it with -3 for any frequency, then those frequencies are
  never considered by cpufreq core as it is exactly same as value of
  CPUFREQ_BOOST_FREQ, i.e. ~2.

The best way to get this fixed is by creating another field flags which
will be used for such flags. This patch does that. Along with that various
drivers need modifications due to the change of struct cpufreq_frequency_table.

Reviewed-by: Gautham R Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-04-07 14:43:50 +02:00

146 lines
3.1 KiB
C

/*
* Copyright (C) 2006 - 2008 Lemote Inc. & Insititute of Computing Technology
* Author: Yanhua, yanh@lemote.com
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/clk.h>
#include <linux/cpufreq.h>
#include <linux/errno.h>
#include <linux/export.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <asm/clock.h>
#include <asm/mach-loongson/loongson.h>
static LIST_HEAD(clock_list);
static DEFINE_SPINLOCK(clock_lock);
static DEFINE_MUTEX(clock_list_sem);
/* Minimum CLK support */
enum {
DC_ZERO, DC_25PT = 2, DC_37PT, DC_50PT, DC_62PT, DC_75PT,
DC_87PT, DC_DISABLE, DC_RESV
};
struct cpufreq_frequency_table loongson2_clockmod_table[] = {
{0, DC_RESV, CPUFREQ_ENTRY_INVALID},
{0, DC_ZERO, CPUFREQ_ENTRY_INVALID},
{0, DC_25PT, 0},
{0, DC_37PT, 0},
{0, DC_50PT, 0},
{0, DC_62PT, 0},
{0, DC_75PT, 0},
{0, DC_87PT, 0},
{0, DC_DISABLE, 0},
{0, DC_RESV, CPUFREQ_TABLE_END},
};
EXPORT_SYMBOL_GPL(loongson2_clockmod_table);
static struct clk cpu_clk = {
.name = "cpu_clk",
.flags = CLK_ALWAYS_ENABLED | CLK_RATE_PROPAGATES,
.rate = 800000000,
};
struct clk *clk_get(struct device *dev, const char *id)
{
return &cpu_clk;
}
EXPORT_SYMBOL(clk_get);
static void propagate_rate(struct clk *clk)
{
struct clk *clkp;
list_for_each_entry(clkp, &clock_list, node) {
if (likely(clkp->parent != clk))
continue;
if (likely(clkp->ops && clkp->ops->recalc))
clkp->ops->recalc(clkp);
if (unlikely(clkp->flags & CLK_RATE_PROPAGATES))
propagate_rate(clkp);
}
}
int clk_enable(struct clk *clk)
{
return 0;
}
EXPORT_SYMBOL(clk_enable);
void clk_disable(struct clk *clk)
{
}
EXPORT_SYMBOL(clk_disable);
unsigned long clk_get_rate(struct clk *clk)
{
return (unsigned long)clk->rate;
}
EXPORT_SYMBOL(clk_get_rate);
void clk_put(struct clk *clk)
{
}
EXPORT_SYMBOL(clk_put);
int clk_set_rate(struct clk *clk, unsigned long rate)
{
int ret = 0;
int regval;
int i;
if (likely(clk->ops && clk->ops->set_rate)) {
unsigned long flags;
spin_lock_irqsave(&clock_lock, flags);
ret = clk->ops->set_rate(clk, rate, 0);
spin_unlock_irqrestore(&clock_lock, flags);
}
if (unlikely(clk->flags & CLK_RATE_PROPAGATES))
propagate_rate(clk);
for (i = 0; loongson2_clockmod_table[i].frequency != CPUFREQ_TABLE_END;
i++) {
if (loongson2_clockmod_table[i].frequency ==
CPUFREQ_ENTRY_INVALID)
continue;
if (rate == loongson2_clockmod_table[i].frequency)
break;
}
if (rate != loongson2_clockmod_table[i].frequency)
return -ENOTSUPP;
clk->rate = rate;
regval = LOONGSON_CHIPCFG0;
regval = (regval & ~0x7) |
(loongson2_clockmod_table[i].driver_data - 1);
LOONGSON_CHIPCFG0 = regval;
return ret;
}
EXPORT_SYMBOL_GPL(clk_set_rate);
long clk_round_rate(struct clk *clk, unsigned long rate)
{
if (likely(clk->ops && clk->ops->round_rate)) {
unsigned long flags, rounded;
spin_lock_irqsave(&clock_lock, flags);
rounded = clk->ops->round_rate(clk, rate);
spin_unlock_irqrestore(&clock_lock, flags);
return rounded;
}
return rate;
}
EXPORT_SYMBOL_GPL(clk_round_rate);