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Diffstat (limited to '')
-rw-r--r-- | arch/mips/lantiq/clk.c | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/arch/mips/lantiq/clk.c b/arch/mips/lantiq/clk.c new file mode 100644 index 000000000..f5fab99d1 --- /dev/null +++ b/arch/mips/lantiq/clk.c @@ -0,0 +1,202 @@ +/* + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + * + * Copyright (C) 2010 Thomas Langer <thomas.langer@lantiq.com> + * Copyright (C) 2010 John Crispin <john@phrozen.org> + */ +#include <linux/io.h> +#include <linux/export.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/clk.h> +#include <linux/clkdev.h> +#include <linux/err.h> +#include <linux/list.h> + +#include <asm/time.h> +#include <asm/irq.h> +#include <asm/div64.h> + +#include <lantiq_soc.h> + +#include "clk.h" +#include "prom.h" + +/* lantiq socs have 3 static clocks */ +static struct clk cpu_clk_generic[4]; + +void clkdev_add_static(unsigned long cpu, unsigned long fpi, + unsigned long io, unsigned long ppe) +{ + cpu_clk_generic[0].rate = cpu; + cpu_clk_generic[1].rate = fpi; + cpu_clk_generic[2].rate = io; + cpu_clk_generic[3].rate = ppe; +} + +struct clk *clk_get_cpu(void) +{ + return &cpu_clk_generic[0]; +} + +struct clk *clk_get_fpi(void) +{ + return &cpu_clk_generic[1]; +} +EXPORT_SYMBOL_GPL(clk_get_fpi); + +struct clk *clk_get_io(void) +{ + return &cpu_clk_generic[2]; +} + +struct clk *clk_get_ppe(void) +{ + return &cpu_clk_generic[3]; +} +EXPORT_SYMBOL_GPL(clk_get_ppe); + +static inline int clk_good(struct clk *clk) +{ + return clk && !IS_ERR(clk); +} + +unsigned long clk_get_rate(struct clk *clk) +{ + if (unlikely(!clk_good(clk))) + return 0; + + if (clk->rate != 0) + return clk->rate; + + if (clk->get_rate != NULL) + return clk->get_rate(); + + return 0; +} +EXPORT_SYMBOL(clk_get_rate); + +int clk_set_rate(struct clk *clk, unsigned long rate) +{ + if (unlikely(!clk_good(clk))) + return 0; + if (clk->rates && *clk->rates) { + unsigned long *r = clk->rates; + + while (*r && (*r != rate)) + r++; + if (!*r) { + pr_err("clk %s.%s: trying to set invalid rate %ld\n", + clk->cl.dev_id, clk->cl.con_id, rate); + return -1; + } + } + clk->rate = rate; + return 0; +} +EXPORT_SYMBOL(clk_set_rate); + +long clk_round_rate(struct clk *clk, unsigned long rate) +{ + if (unlikely(!clk_good(clk))) + return 0; + if (clk->rates && *clk->rates) { + unsigned long *r = clk->rates; + + while (*r && (*r != rate)) + r++; + if (!*r) { + return clk->rate; + } + } + return rate; +} +EXPORT_SYMBOL(clk_round_rate); + +int clk_enable(struct clk *clk) +{ + if (unlikely(!clk_good(clk))) + return -1; + + if (clk->enable) + return clk->enable(clk); + + return -1; +} +EXPORT_SYMBOL(clk_enable); + +void clk_disable(struct clk *clk) +{ + if (unlikely(!clk_good(clk))) + return; + + if (clk->disable) + clk->disable(clk); +} +EXPORT_SYMBOL(clk_disable); + +int clk_activate(struct clk *clk) +{ + if (unlikely(!clk_good(clk))) + return -1; + + if (clk->activate) + return clk->activate(clk); + + return -1; +} +EXPORT_SYMBOL(clk_activate); + +void clk_deactivate(struct clk *clk) +{ + if (unlikely(!clk_good(clk))) + return; + + if (clk->deactivate) + clk->deactivate(clk); +} +EXPORT_SYMBOL(clk_deactivate); + +struct clk *clk_get_parent(struct clk *clk) +{ + return NULL; +} +EXPORT_SYMBOL(clk_get_parent); + +int clk_set_parent(struct clk *clk, struct clk *parent) +{ + return 0; +} +EXPORT_SYMBOL(clk_set_parent); + +static inline u32 get_counter_resolution(void) +{ + u32 res; + + __asm__ __volatile__( + ".set push\n" + ".set mips32r2\n" + "rdhwr %0, $3\n" + ".set pop\n" + : "=&r" (res) + : /* no input */ + : "memory"); + + return res; +} + +void __init plat_time_init(void) +{ + struct clk *clk; + + ltq_soc_init(); + + clk = clk_get_cpu(); + mips_hpt_frequency = clk_get_rate(clk) / get_counter_resolution(); + write_c0_compare(read_c0_count()); + pr_info("CPU Clock: %ldMHz\n", clk_get_rate(clk) / 1000000); + clk_put(clk); +} |