diff options
Diffstat (limited to 'drivers/clk/versatile/clk-vexpress.c')
| -rw-r--r-- | drivers/clk/versatile/clk-vexpress.c | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/drivers/clk/versatile/clk-vexpress.c b/drivers/clk/versatile/clk-vexpress.c new file mode 100644 index 000000000000..c742ac7c60bb --- /dev/null +++ b/drivers/clk/versatile/clk-vexpress.c @@ -0,0 +1,142 @@ +/* + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * Copyright (C) 2012 ARM Limited + */ + +#include <linux/clkdev.h> +#include <linux/clk-provider.h> +#include <linux/err.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/vexpress.h> + +#include <asm/hardware/sp810.h> + +static struct clk *vexpress_sp810_timerclken[4]; +static DEFINE_SPINLOCK(vexpress_sp810_lock); + +static void __init vexpress_sp810_init(void __iomem *base) +{ + int i; + + if (WARN_ON(!base)) + return; + + for (i = 0; i < ARRAY_SIZE(vexpress_sp810_timerclken); i++) { + char name[12]; + const char *parents[] = { + "v2m:refclk32khz", /* REFCLK */ + "v2m:refclk1mhz" /* TIMCLK */ + }; + + snprintf(name, ARRAY_SIZE(name), "timerclken%d", i); + + vexpress_sp810_timerclken[i] = clk_register_mux(NULL, name, + parents, 2, 0, base + SCCTRL, + SCCTRL_TIMERENnSEL_SHIFT(i), 1, + 0, &vexpress_sp810_lock); + + if (WARN_ON(IS_ERR(vexpress_sp810_timerclken[i]))) + break; + } +} + + +static const char * const vexpress_clk_24mhz_periphs[] __initconst = { + "mb:uart0", "mb:uart1", "mb:uart2", "mb:uart3", + "mb:mmci", "mb:kmi0", "mb:kmi1" +}; + +void __init vexpress_clk_init(void __iomem *sp810_base) +{ + struct clk *clk; + int i; + + clk = clk_register_fixed_rate(NULL, "dummy_apb_pclk", NULL, + CLK_IS_ROOT, 0); + WARN_ON(clk_register_clkdev(clk, "apb_pclk", NULL)); + + clk = clk_register_fixed_rate(NULL, "v2m:clk_24mhz", NULL, + CLK_IS_ROOT, 24000000); + for (i = 0; i < ARRAY_SIZE(vexpress_clk_24mhz_periphs); i++) + WARN_ON(clk_register_clkdev(clk, NULL, + vexpress_clk_24mhz_periphs[i])); + + clk = clk_register_fixed_rate(NULL, "v2m:refclk32khz", NULL, + CLK_IS_ROOT, 32768); + WARN_ON(clk_register_clkdev(clk, NULL, "v2m:wdt")); + + clk = clk_register_fixed_rate(NULL, "v2m:refclk1mhz", NULL, + CLK_IS_ROOT, 1000000); + + vexpress_sp810_init(sp810_base); + + for (i = 0; i < ARRAY_SIZE(vexpress_sp810_timerclken); i++) + WARN_ON(clk_set_parent(vexpress_sp810_timerclken[i], clk)); + + WARN_ON(clk_register_clkdev(vexpress_sp810_timerclken[0], + "v2m-timer0", "sp804")); + WARN_ON(clk_register_clkdev(vexpress_sp810_timerclken[1], + "v2m-timer1", "sp804")); +} + +#if defined(CONFIG_OF) + +struct clk *vexpress_sp810_of_get(struct of_phandle_args *clkspec, void *data) +{ + if (WARN_ON(clkspec->args_count != 1 || clkspec->args[0] > + ARRAY_SIZE(vexpress_sp810_timerclken))) + return NULL; + + return vexpress_sp810_timerclken[clkspec->args[0]]; +} + +static const __initconst struct of_device_id vexpress_fixed_clk_match[] = { + { .compatible = "fixed-clock", .data = of_fixed_clk_setup, }, + { .compatible = "arm,vexpress-osc", .data = vexpress_osc_of_setup, }, + {} +}; + +void __init vexpress_clk_of_init(void) +{ + struct device_node *node; + struct clk *clk; + struct clk *refclk, *timclk; + + of_clk_init(vexpress_fixed_clk_match); + + node = of_find_compatible_node(NULL, NULL, "arm,sp810"); + vexpress_sp810_init(of_iomap(node, 0)); + of_clk_add_provider(node, vexpress_sp810_of_get, NULL); + + /* Select "better" (faster) parent for SP804 timers */ + refclk = of_clk_get_by_name(node, "refclk"); + timclk = of_clk_get_by_name(node, "timclk"); + if (!WARN_ON(IS_ERR(refclk) || IS_ERR(timclk))) { + int i = 0; + + if (clk_get_rate(refclk) > clk_get_rate(timclk)) + clk = refclk; + else + clk = timclk; + + for (i = 0; i < ARRAY_SIZE(vexpress_sp810_timerclken); i++) + WARN_ON(clk_set_parent(vexpress_sp810_timerclken[i], + clk)); + } + + WARN_ON(clk_register_clkdev(vexpress_sp810_timerclken[0], + "v2m-timer0", "sp804")); + WARN_ON(clk_register_clkdev(vexpress_sp810_timerclken[1], + "v2m-timer1", "sp804")); +} + +#endif |