diff options
Diffstat (limited to 'arch/powerpc/sysdev/mpc5xxx_clocks.c')
-rw-r--r-- | arch/powerpc/sysdev/mpc5xxx_clocks.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/mpc5xxx_clocks.c b/arch/powerpc/sysdev/mpc5xxx_clocks.c new file mode 100644 index 000000000..f4f0301b9 --- /dev/null +++ b/arch/powerpc/sysdev/mpc5xxx_clocks.c @@ -0,0 +1,33 @@ +/** + * mpc5xxx_get_bus_frequency - Find the bus frequency for a device + * @node: device node + * + * Returns bus frequency (IPS on MPC512x, IPB on MPC52xx), + * or 0 if the bus frequency cannot be found. + */ + +#include <linux/kernel.h> +#include <linux/of_platform.h> +#include <linux/export.h> +#include <asm/mpc5xxx.h> + +unsigned long mpc5xxx_get_bus_frequency(struct device_node *node) +{ + struct device_node *np; + const unsigned int *p_bus_freq = NULL; + + of_node_get(node); + while (node) { + p_bus_freq = of_get_property(node, "bus-frequency", NULL); + if (p_bus_freq) + break; + + np = of_get_parent(node); + of_node_put(node); + node = np; + } + of_node_put(node); + + return p_bus_freq ? *p_bus_freq : 0; +} +EXPORT_SYMBOL(mpc5xxx_get_bus_frequency); |