diff options
Diffstat (limited to 'kernel/arch/mips/loongson/lemote-2f/clock.c')
-rw-r--r-- | kernel/arch/mips/loongson/lemote-2f/clock.c | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/kernel/arch/mips/loongson/lemote-2f/clock.c b/kernel/arch/mips/loongson/lemote-2f/clock.c new file mode 100644 index 000000000..462e34d46 --- /dev/null +++ b/kernel/arch/mips/loongson/lemote-2f/clock.c @@ -0,0 +1,140 @@ +/* + * 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) +{ + unsigned int rate_khz = rate / 1000; + struct cpufreq_frequency_table *pos; + int ret = 0; + int regval; + + 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); + + cpufreq_for_each_valid_entry(pos, loongson2_clockmod_table) + if (rate_khz == pos->frequency) + break; + if (rate_khz != pos->frequency) + return -ENOTSUPP; + + clk->rate = rate; + + regval = LOONGSON_CHIPCFG(0); + regval = (regval & ~0x7) | (pos->driver_data - 1); + LOONGSON_CHIPCFG(0) = 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); |