diff options
Diffstat (limited to 'arch/mips/loongson1/common/clock.c')
-rw-r--r-- | arch/mips/loongson1/common/clock.c | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/arch/mips/loongson1/common/clock.c b/arch/mips/loongson1/common/clock.c new file mode 100644 index 000000000000..2d98fb030596 --- /dev/null +++ b/arch/mips/loongson1/common/clock.c @@ -0,0 +1,165 @@ +/* + * Copyright (c) 2011 Zhang, Keguang <keguang.zhang@gmail.com> + * + * 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/list.h> +#include <linux/mutex.h> +#include <linux/clk.h> +#include <linux/err.h> +#include <asm/clock.h> +#include <asm/time.h> + +#include <loongson1.h> + +static LIST_HEAD(clocks); +static DEFINE_MUTEX(clocks_mutex); + +struct clk *clk_get(struct device *dev, const char *name) +{ + struct clk *c; + struct clk *ret = NULL; + + mutex_lock(&clocks_mutex); + list_for_each_entry(c, &clocks, node) { + if (!strcmp(c->name, name)) { + ret = c; + break; + } + } + mutex_unlock(&clocks_mutex); + + return ret; +} +EXPORT_SYMBOL(clk_get); + +unsigned long clk_get_rate(struct clk *clk) +{ + return clk->rate; +} +EXPORT_SYMBOL(clk_get_rate); + +static void pll_clk_init(struct clk *clk) +{ + u32 pll; + + pll = __raw_readl(LS1X_CLK_PLL_FREQ); + clk->rate = (12 + (pll & 0x3f)) * 33 / 2 + + ((pll >> 8) & 0x3ff) * 33 / 1024 / 2; + clk->rate *= 1000000; +} + +static void cpu_clk_init(struct clk *clk) +{ + u32 pll, ctrl; + + pll = clk_get_rate(clk->parent); + ctrl = __raw_readl(LS1X_CLK_PLL_DIV) & DIV_CPU; + clk->rate = pll / (ctrl >> DIV_CPU_SHIFT); +} + +static void ddr_clk_init(struct clk *clk) +{ + u32 pll, ctrl; + + pll = clk_get_rate(clk->parent); + ctrl = __raw_readl(LS1X_CLK_PLL_DIV) & DIV_DDR; + clk->rate = pll / (ctrl >> DIV_DDR_SHIFT); +} + +static void dc_clk_init(struct clk *clk) +{ + u32 pll, ctrl; + + pll = clk_get_rate(clk->parent); + ctrl = __raw_readl(LS1X_CLK_PLL_DIV) & DIV_DC; + clk->rate = pll / (ctrl >> DIV_DC_SHIFT); +} + +static struct clk_ops pll_clk_ops = { + .init = pll_clk_init, +}; + +static struct clk_ops cpu_clk_ops = { + .init = cpu_clk_init, +}; + +static struct clk_ops ddr_clk_ops = { + .init = ddr_clk_init, +}; + +static struct clk_ops dc_clk_ops = { + .init = dc_clk_init, +}; + +static struct clk pll_clk = { + .name = "pll", + .ops = &pll_clk_ops, +}; + +static struct clk cpu_clk = { + .name = "cpu", + .parent = &pll_clk, + .ops = &cpu_clk_ops, +}; + +static struct clk ddr_clk = { + .name = "ddr", + .parent = &pll_clk, + .ops = &ddr_clk_ops, +}; + +static struct clk dc_clk = { + .name = "dc", + .parent = &pll_clk, + .ops = &dc_clk_ops, +}; + +int clk_register(struct clk *clk) +{ + mutex_lock(&clocks_mutex); + list_add(&clk->node, &clocks); + if (clk->ops->init) + clk->ops->init(clk); + mutex_unlock(&clocks_mutex); + + return 0; +} +EXPORT_SYMBOL(clk_register); + +static struct clk *ls1x_clks[] = { + &pll_clk, + &cpu_clk, + &ddr_clk, + &dc_clk, +}; + +int __init ls1x_clock_init(void) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(ls1x_clks); i++) + clk_register(ls1x_clks[i]); + + return 0; +} + +void __init plat_time_init(void) +{ + struct clk *clk; + + /* Initialize LS1X clocks */ + ls1x_clock_init(); + + /* setup mips r4k timer */ + clk = clk_get(NULL, "cpu"); + if (IS_ERR(clk)) + panic("unable to get dc clock, err=%ld", PTR_ERR(clk)); + + mips_hpt_frequency = clk_get_rate(clk) / 2; +} |