diff options
| author | Jonathan Herman <hermanjl@cs.unc.edu> | 2013-01-22 10:38:37 -0500 |
|---|---|---|
| committer | Jonathan Herman <hermanjl@cs.unc.edu> | 2013-01-22 10:38:37 -0500 |
| commit | fcc9d2e5a6c89d22b8b773a64fb4ad21ac318446 (patch) | |
| tree | a57612d1888735a2ec7972891b68c1ac5ec8faea /arch/mips/kernel/cpufreq | |
| parent | 8dea78da5cee153b8af9c07a2745f6c55057fe12 (diff) | |
Diffstat (limited to 'arch/mips/kernel/cpufreq')
| -rw-r--r-- | arch/mips/kernel/cpufreq/loongson2_clock.c | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/arch/mips/kernel/cpufreq/loongson2_clock.c b/arch/mips/kernel/cpufreq/loongson2_clock.c new file mode 100644 index 00000000000..cefc6e259ba --- /dev/null +++ b/arch/mips/kernel/cpufreq/loongson2_clock.c | |||
| @@ -0,0 +1,170 @@ | |||
| 1 | /* | ||
| 2 | * Copyright (C) 2006 - 2008 Lemote Inc. & Insititute of Computing Technology | ||
| 3 | * Author: Yanhua, yanh@lemote.com | ||
| 4 | * | ||
| 5 | * This file is subject to the terms and conditions of the GNU General Public | ||
| 6 | * License. See the file "COPYING" in the main directory of this archive | ||
| 7 | * for more details. | ||
| 8 | */ | ||
| 9 | |||
| 10 | #include <linux/cpufreq.h> | ||
| 11 | #include <linux/platform_device.h> | ||
| 12 | |||
| 13 | #include <asm/clock.h> | ||
| 14 | |||
| 15 | #include <loongson.h> | ||
| 16 | |||
| 17 | static LIST_HEAD(clock_list); | ||
| 18 | static DEFINE_SPINLOCK(clock_lock); | ||
| 19 | static DEFINE_MUTEX(clock_list_sem); | ||
| 20 | |||
| 21 | /* Minimum CLK support */ | ||
| 22 | enum { | ||
| 23 | DC_ZERO, DC_25PT = 2, DC_37PT, DC_50PT, DC_62PT, DC_75PT, | ||
| 24 | DC_87PT, DC_DISABLE, DC_RESV | ||
| 25 | }; | ||
| 26 | |||
| 27 | struct cpufreq_frequency_table loongson2_clockmod_table[] = { | ||
| 28 | {DC_RESV, CPUFREQ_ENTRY_INVALID}, | ||
| 29 | {DC_ZERO, CPUFREQ_ENTRY_INVALID}, | ||
| 30 | {DC_25PT, 0}, | ||
| 31 | {DC_37PT, 0}, | ||
| 32 | {DC_50PT, 0}, | ||
| 33 | {DC_62PT, 0}, | ||
| 34 | {DC_75PT, 0}, | ||
| 35 | {DC_87PT, 0}, | ||
| 36 | {DC_DISABLE, 0}, | ||
| 37 | {DC_RESV, CPUFREQ_TABLE_END}, | ||
| 38 | }; | ||
| 39 | EXPORT_SYMBOL_GPL(loongson2_clockmod_table); | ||
| 40 | |||
| 41 | static struct clk cpu_clk = { | ||
| 42 | .name = "cpu_clk", | ||
| 43 | .flags = CLK_ALWAYS_ENABLED | CLK_RATE_PROPAGATES, | ||
| 44 | .rate = 800000000, | ||
| 45 | }; | ||
| 46 | |||
| 47 | struct clk *clk_get(struct device *dev, const char *id) | ||
| 48 | { | ||
| 49 | return &cpu_clk; | ||
| 50 | } | ||
| 51 | EXPORT_SYMBOL(clk_get); | ||
| 52 | |||
| 53 | static void propagate_rate(struct clk *clk) | ||
| 54 | { | ||
| 55 | struct clk *clkp; | ||
| 56 | |||
| 57 | list_for_each_entry(clkp, &clock_list, node) { | ||
| 58 | if (likely(clkp->parent != clk)) | ||
| 59 | continue; | ||
| 60 | if (likely(clkp->ops && clkp->ops->recalc)) | ||
| 61 | clkp->ops->recalc(clkp); | ||
| 62 | if (unlikely(clkp->flags & CLK_RATE_PROPAGATES)) | ||
| 63 | propagate_rate(clkp); | ||
| 64 | } | ||
| 65 | } | ||
| 66 | |||
| 67 | int clk_enable(struct clk *clk) | ||
| 68 | { | ||
| 69 | return 0; | ||
| 70 | } | ||
| 71 | EXPORT_SYMBOL(clk_enable); | ||
| 72 | |||
| 73 | void clk_disable(struct clk *clk) | ||
| 74 | { | ||
| 75 | } | ||
| 76 | EXPORT_SYMBOL(clk_disable); | ||
| 77 | |||
| 78 | unsigned long clk_get_rate(struct clk *clk) | ||
| 79 | { | ||
| 80 | return (unsigned long)clk->rate; | ||
| 81 | } | ||
| 82 | EXPORT_SYMBOL(clk_get_rate); | ||
| 83 | |||
| 84 | void clk_put(struct clk *clk) | ||
| 85 | { | ||
| 86 | } | ||
| 87 | EXPORT_SYMBOL(clk_put); | ||
| 88 | |||
| 89 | int clk_set_rate(struct clk *clk, unsigned long rate) | ||
| 90 | { | ||
| 91 | return clk_set_rate_ex(clk, rate, 0); | ||
| 92 | } | ||
| 93 | EXPORT_SYMBOL_GPL(clk_set_rate); | ||
| 94 | |||
| 95 | int clk_set_rate_ex(struct clk *clk, unsigned long rate, int algo_id) | ||
| 96 | { | ||
| 97 | int ret = 0; | ||
| 98 | int regval; | ||
| 99 | int i; | ||
| 100 | |||
| 101 | if (likely(clk->ops && clk->ops->set_rate)) { | ||
| 102 | unsigned long flags; | ||
| 103 | |||
| 104 | spin_lock_irqsave(&clock_lock, flags); | ||
| 105 | ret = clk->ops->set_rate(clk, rate, algo_id); | ||
| 106 | spin_unlock_irqrestore(&clock_lock, flags); | ||
| 107 | } | ||
| 108 | |||
| 109 | if (unlikely(clk->flags & CLK_RATE_PROPAGATES)) | ||
| 110 | propagate_rate(clk); | ||
| 111 | |||
| 112 | for (i = 0; loongson2_clockmod_table[i].frequency != CPUFREQ_TABLE_END; | ||
| 113 | i++) { | ||
| 114 | if (loongson2_clockmod_table[i].frequency == | ||
| 115 | CPUFREQ_ENTRY_INVALID) | ||
| 116 | continue; | ||
| 117 | if (rate == loongson2_clockmod_table[i].frequency) | ||
| 118 | break; | ||
| 119 | } | ||
| 120 | if (rate != loongson2_clockmod_table[i].frequency) | ||
| 121 | return -ENOTSUPP; | ||
| 122 | |||
| 123 | clk->rate = rate; | ||
| 124 | |||
| 125 | regval = LOONGSON_CHIPCFG0; | ||
| 126 | regval = (regval & ~0x7) | (loongson2_clockmod_table[i].index - 1); | ||
| 127 | LOONGSON_CHIPCFG0 = regval; | ||
| 128 | |||
| 129 | return ret; | ||
| 130 | } | ||
| 131 | EXPORT_SYMBOL_GPL(clk_set_rate_ex); | ||
| 132 | |||
| 133 | long clk_round_rate(struct clk *clk, unsigned long rate) | ||
| 134 | { | ||
| 135 | if (likely(clk->ops && clk->ops->round_rate)) { | ||
| 136 | unsigned long flags, rounded; | ||
| 137 | |||
| 138 | spin_lock_irqsave(&clock_lock, flags); | ||
| 139 | rounded = clk->ops->round_rate(clk, rate); | ||
| 140 | spin_unlock_irqrestore(&clock_lock, flags); | ||
| 141 | |||
| 142 | return rounded; | ||
| 143 | } | ||
| 144 | |||
| 145 | return rate; | ||
| 146 | } | ||
| 147 | EXPORT_SYMBOL_GPL(clk_round_rate); | ||
| 148 | |||
| 149 | /* | ||
| 150 | * This is the simple version of Loongson-2 wait, Maybe we need do this in | ||
| 151 | * interrupt disabled content | ||
| 152 | */ | ||
| 153 | |||
| 154 | DEFINE_SPINLOCK(loongson2_wait_lock); | ||
| 155 | void loongson2_cpu_wait(void) | ||
| 156 | { | ||
| 157 | u32 cpu_freq; | ||
| 158 | unsigned long flags; | ||
| 159 | |||
| 160 | spin_lock_irqsave(&loongson2_wait_lock, flags); | ||
| 161 | cpu_freq = LOONGSON_CHIPCFG0; | ||
| 162 | LOONGSON_CHIPCFG0 &= ~0x7; /* Put CPU into wait mode */ | ||
| 163 | LOONGSON_CHIPCFG0 = cpu_freq; /* Restore CPU state */ | ||
| 164 | spin_unlock_irqrestore(&loongson2_wait_lock, flags); | ||
| 165 | } | ||
| 166 | EXPORT_SYMBOL_GPL(loongson2_cpu_wait); | ||
| 167 | |||
| 168 | MODULE_AUTHOR("Yanhua <yanh@lemote.com>"); | ||
| 169 | MODULE_DESCRIPTION("cpufreq driver for Loongson 2F"); | ||
| 170 | MODULE_LICENSE("GPL"); | ||
