diff options
Diffstat (limited to 'arch/arm/mach-davinci/clock.c')
-rw-r--r-- | arch/arm/mach-davinci/clock.c | 323 |
1 files changed, 323 insertions, 0 deletions
diff --git a/arch/arm/mach-davinci/clock.c b/arch/arm/mach-davinci/clock.c new file mode 100644 index 00000000000..139ceaa35e2 --- /dev/null +++ b/arch/arm/mach-davinci/clock.c @@ -0,0 +1,323 @@ +/* + * TI DaVinci clock config file + * + * Copyright (C) 2006 Texas Instruments. + * + * 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/kernel.h> +#include <linux/init.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/mutex.h> +#include <linux/platform_device.h> + +#include <asm/hardware.h> +#include <asm/io.h> + +#include <asm/arch/psc.h> +#include "clock.h" + +/* PLL/Reset register offsets */ +#define PLLM 0x110 + +static LIST_HEAD(clocks); +static DEFINE_MUTEX(clocks_mutex); +static DEFINE_SPINLOCK(clockfw_lock); + +static unsigned int commonrate; +static unsigned int armrate; +static unsigned int fixedrate = 27000000; /* 27 MHZ */ + +extern void davinci_psc_config(unsigned int domain, unsigned int id, char enable); + +/* + * Returns a clock. Note that we first try to use device id on the bus + * and clock name. If this fails, we try to use clock name only. + */ +struct clk *clk_get(struct device *dev, const char *id) +{ + struct clk *p, *clk = ERR_PTR(-ENOENT); + int idno; + + if (dev == NULL || dev->bus != &platform_bus_type) + idno = -1; + else + idno = to_platform_device(dev)->id; + + mutex_lock(&clocks_mutex); + + list_for_each_entry(p, &clocks, node) { + if (p->id == idno && + strcmp(id, p->name) == 0 && try_module_get(p->owner)) { + clk = p; + goto found; + } + } + + list_for_each_entry(p, &clocks, node) { + if (strcmp(id, p->name) == 0 && try_module_get(p->owner)) { + clk = p; + break; + } + } + +found: + mutex_unlock(&clocks_mutex); + + return clk; +} +EXPORT_SYMBOL(clk_get); + +void clk_put(struct clk *clk) +{ + if (clk && !IS_ERR(clk)) + module_put(clk->owner); +} +EXPORT_SYMBOL(clk_put); + +static int __clk_enable(struct clk *clk) +{ + if (clk->flags & ALWAYS_ENABLED) + return 0; + + davinci_psc_config(DAVINCI_GPSC_ARMDOMAIN, clk->lpsc, 1); + return 0; +} + +static void __clk_disable(struct clk *clk) +{ + if (clk->usecount) + return; + + davinci_psc_config(DAVINCI_GPSC_ARMDOMAIN, clk->lpsc, 0); +} + +int clk_enable(struct clk *clk) +{ + unsigned long flags; + int ret = 0; + + if (clk == NULL || IS_ERR(clk)) + return -EINVAL; + + if (clk->usecount++ == 0) { + spin_lock_irqsave(&clockfw_lock, flags); + ret = __clk_enable(clk); + spin_unlock_irqrestore(&clockfw_lock, flags); + } + + return ret; +} +EXPORT_SYMBOL(clk_enable); + +void clk_disable(struct clk *clk) +{ + unsigned long flags; + + if (clk == NULL || IS_ERR(clk)) + return; + + if (clk->usecount > 0 && !(--clk->usecount)) { + spin_lock_irqsave(&clockfw_lock, flags); + __clk_disable(clk); + spin_unlock_irqrestore(&clockfw_lock, flags); + } +} +EXPORT_SYMBOL(clk_disable); + +unsigned long clk_get_rate(struct clk *clk) +{ + if (clk == NULL || IS_ERR(clk)) + return -EINVAL; + + return *(clk->rate); +} +EXPORT_SYMBOL(clk_get_rate); + +long clk_round_rate(struct clk *clk, unsigned long rate) +{ + if (clk == NULL || IS_ERR(clk)) + return -EINVAL; + + return *(clk->rate); +} +EXPORT_SYMBOL(clk_round_rate); + +int clk_set_rate(struct clk *clk, unsigned long rate) +{ + if (clk == NULL || IS_ERR(clk)) + return -EINVAL; + + /* changing the clk rate is not supported */ + return -EINVAL; +} +EXPORT_SYMBOL(clk_set_rate); + +int clk_register(struct clk *clk) +{ + if (clk == NULL || IS_ERR(clk)) + return -EINVAL; + + mutex_lock(&clocks_mutex); + list_add(&clk->node, &clocks); + mutex_unlock(&clocks_mutex); + + return 0; +} +EXPORT_SYMBOL(clk_register); + +void clk_unregister(struct clk *clk) +{ + if (clk == NULL || IS_ERR(clk)) + return; + + mutex_lock(&clocks_mutex); + list_del(&clk->node); + mutex_unlock(&clocks_mutex); +} +EXPORT_SYMBOL(clk_unregister); + +static struct clk davinci_clks[] = { + { + .name = "ARMCLK", + .rate = &armrate, + .lpsc = -1, + .flags = ALWAYS_ENABLED, + }, + { + .name = "UART", + .rate = &fixedrate, + .lpsc = DAVINCI_LPSC_UART0, + }, + { + .name = "EMACCLK", + .rate = &commonrate, + .lpsc = DAVINCI_LPSC_EMAC_WRAPPER, + }, + { + .name = "I2CCLK", + .rate = &fixedrate, + .lpsc = DAVINCI_LPSC_I2C, + }, + { + .name = "IDECLK", + .rate = &commonrate, + .lpsc = DAVINCI_LPSC_ATA, + }, + { + .name = "McBSPCLK", + .rate = &commonrate, + .lpsc = DAVINCI_LPSC_McBSP, + }, + { + .name = "MMCSDCLK", + .rate = &commonrate, + .lpsc = DAVINCI_LPSC_MMC_SD, + }, + { + .name = "SPICLK", + .rate = &commonrate, + .lpsc = DAVINCI_LPSC_SPI, + }, + { + .name = "gpio", + .rate = &commonrate, + .lpsc = DAVINCI_LPSC_GPIO, + }, + { + .name = "AEMIFCLK", + .rate = &commonrate, + .lpsc = DAVINCI_LPSC_AEMIF, + .usecount = 1, + } +}; + +int __init davinci_clk_init(void) +{ + struct clk *clkp; + int count = 0; + u32 pll_mult; + + pll_mult = davinci_readl(DAVINCI_PLL_CNTRL0_BASE + PLLM); + commonrate = ((pll_mult + 1) * 27000000) / 6; + armrate = ((pll_mult + 1) * 27000000) / 2; + + for (clkp = davinci_clks; count < ARRAY_SIZE(davinci_clks); + count++, clkp++) { + clk_register(clkp); + + /* Turn on clocks that have been enabled in the + * table above */ + if (clkp->usecount) + clk_enable(clkp); + } + + return 0; +} + +#ifdef CONFIG_PROC_FS +#include <linux/proc_fs.h> +#include <linux/seq_file.h> + +static void *davinci_ck_start(struct seq_file *m, loff_t *pos) +{ + return *pos < 1 ? (void *)1 : NULL; +} + +static void *davinci_ck_next(struct seq_file *m, void *v, loff_t *pos) +{ + ++*pos; + return NULL; +} + +static void davinci_ck_stop(struct seq_file *m, void *v) +{ +} + +static int davinci_ck_show(struct seq_file *m, void *v) +{ + struct clk *cp; + + list_for_each_entry(cp, &clocks, node) + seq_printf(m,"%s %d %d\n", cp->name, *(cp->rate), cp->usecount); + + return 0; +} + +static struct seq_operations davinci_ck_op = { + .start = davinci_ck_start, + .next = davinci_ck_next, + .stop = davinci_ck_stop, + .show = davinci_ck_show +}; + +static int davinci_ck_open(struct inode *inode, struct file *file) +{ + return seq_open(file, &davinci_ck_op); +} + +static struct file_operations proc_davinci_ck_operations = { + .open = davinci_ck_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + +static int __init davinci_ck_proc_init(void) +{ + struct proc_dir_entry *entry; + + entry = create_proc_entry("davinci_clocks", 0, NULL); + if (entry) + entry->proc_fops = &proc_davinci_ck_operations; + return 0; + +} +__initcall(davinci_ck_proc_init); +#endif /* CONFIG_DEBUG_PROC_FS */ |