18c2ecf20Sopenharmony_ci// SPDX-License-Identifier: GPL-2.0
28c2ecf20Sopenharmony_ci/**
38c2ecf20Sopenharmony_ci * 	mpc5xxx_get_bus_frequency - Find the bus frequency for a device
48c2ecf20Sopenharmony_ci * 	@node:	device node
58c2ecf20Sopenharmony_ci *
68c2ecf20Sopenharmony_ci * 	Returns bus frequency (IPS on MPC512x, IPB on MPC52xx),
78c2ecf20Sopenharmony_ci * 	or 0 if the bus frequency cannot be found.
88c2ecf20Sopenharmony_ci */
98c2ecf20Sopenharmony_ci
108c2ecf20Sopenharmony_ci#include <linux/kernel.h>
118c2ecf20Sopenharmony_ci#include <linux/of_platform.h>
128c2ecf20Sopenharmony_ci#include <linux/export.h>
138c2ecf20Sopenharmony_ci#include <asm/mpc5xxx.h>
148c2ecf20Sopenharmony_ci
158c2ecf20Sopenharmony_ciunsigned long mpc5xxx_get_bus_frequency(struct device_node *node)
168c2ecf20Sopenharmony_ci{
178c2ecf20Sopenharmony_ci	const unsigned int *p_bus_freq = NULL;
188c2ecf20Sopenharmony_ci
198c2ecf20Sopenharmony_ci	of_node_get(node);
208c2ecf20Sopenharmony_ci	while (node) {
218c2ecf20Sopenharmony_ci		p_bus_freq = of_get_property(node, "bus-frequency", NULL);
228c2ecf20Sopenharmony_ci		if (p_bus_freq)
238c2ecf20Sopenharmony_ci			break;
248c2ecf20Sopenharmony_ci
258c2ecf20Sopenharmony_ci		node = of_get_next_parent(node);
268c2ecf20Sopenharmony_ci	}
278c2ecf20Sopenharmony_ci	of_node_put(node);
288c2ecf20Sopenharmony_ci
298c2ecf20Sopenharmony_ci	return p_bus_freq ? *p_bus_freq : 0;
308c2ecf20Sopenharmony_ci}
318c2ecf20Sopenharmony_ciEXPORT_SYMBOL(mpc5xxx_get_bus_frequency);
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