diff options
Diffstat (limited to 'arch/arm/mach-at91/clock.c')
| -rw-r--r-- | arch/arm/mach-at91/clock.c | 56 |
1 files changed, 51 insertions, 5 deletions
diff --git a/arch/arm/mach-at91/clock.c b/arch/arm/mach-at91/clock.c index be51ca7f694d..a0f4d7424cdc 100644 --- a/arch/arm/mach-at91/clock.c +++ b/arch/arm/mach-at91/clock.c @@ -23,6 +23,7 @@ #include <linux/delay.h> #include <linux/clk.h> #include <linux/io.h> +#include <linux/of_address.h> #include <mach/hardware.h> #include <mach/at91_pmc.h> @@ -671,16 +672,12 @@ static void __init at91_upll_usbfs_clock_init(unsigned long main_clock) uhpck.rate_hz /= 1 + ((at91_pmc_read(AT91_PMC_USB) & AT91_PMC_OHCIUSBDIV) >> 8); } -int __init at91_clock_init(unsigned long main_clock) +static int __init at91_pmc_init(unsigned long main_clock) { unsigned tmp, freq, mckr; int i; int pll_overclock = false; - at91_pmc_base = ioremap(AT91_PMC, 256); - if (!at91_pmc_base) - panic("Impossible to ioremap AT91_PMC 0x%x\n", AT91_PMC); - /* * When the bootloader initialized the main oscillator correctly, * there's no problem using the cycle counter. But if it didn't, @@ -802,6 +799,55 @@ int __init at91_clock_init(unsigned long main_clock) return 0; } +#if defined(CONFIG_OF) +static struct of_device_id pmc_ids[] = { + { .compatible = "atmel,at91rm9200-pmc" }, + { /*sentinel*/ } +}; + +static struct of_device_id osc_ids[] = { + { .compatible = "atmel,osc" }, + { /*sentinel*/ } +}; + +int __init at91_dt_clock_init(void) +{ + struct device_node *np; + u32 main_clock = 0; + + np = of_find_matching_node(NULL, pmc_ids); + if (!np) + panic("unable to find compatible pmc node in dtb\n"); + + at91_pmc_base = of_iomap(np, 0); + if (!at91_pmc_base) + panic("unable to map pmc cpu registers\n"); + + of_node_put(np); + + /* retrieve the freqency of fixed clocks from device tree */ + np = of_find_matching_node(NULL, osc_ids); + if (np) { + u32 rate; + if (!of_property_read_u32(np, "clock-frequency", &rate)) + main_clock = rate; + } + + of_node_put(np); + + return at91_pmc_init(main_clock); +} +#endif + +int __init at91_clock_init(unsigned long main_clock) +{ + at91_pmc_base = ioremap(AT91_PMC, 256); + if (!at91_pmc_base) + panic("Impossible to ioremap AT91_PMC 0x%x\n", AT91_PMC); + + return at91_pmc_init(main_clock); +} + /* * Several unused clocks may be active. Turn them off. */ |