1 // SPDX-License-Identifier: GPL-2.0 2 3 #include <linux/kernel.h> 4 #include <linux/export.h> 5 #include <linux/property.h> 6 7 #include <asm/mpc5xxx.h> 8 9 /** 10 * mpc5xxx_fwnode_get_bus_frequency - Find the bus frequency for a firmware node 11 * @fwnode: firmware node 12 * 13 * Returns bus frequency (IPS on MPC512x, IPB on MPC52xx), 14 * or 0 if the bus frequency cannot be found. 15 */ 16 unsigned long mpc5xxx_fwnode_get_bus_frequency(struct fwnode_handle *fwnode) 17 { 18 struct fwnode_handle *parent; 19 u32 bus_freq; 20 int ret; 21 22 ret = fwnode_property_read_u32(fwnode, "bus-frequency", &bus_freq); 23 if (!ret) 24 return bus_freq; 25 26 fwnode_for_each_parent_node(fwnode, parent) { 27 ret = fwnode_property_read_u32(parent, "bus-frequency", &bus_freq); 28 if (!ret) { 29 fwnode_handle_put(parent); 30 return bus_freq; 31 } 32 } 33 34 return 0; 35 } 36 EXPORT_SYMBOL(mpc5xxx_fwnode_get_bus_frequency); 37