/* * SH-Mobile Timer * * Copyright (C) 2010 Magnus Damm * Copyright (C) 2002 - 2009 Paul Mundt * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; version 2 of the License. * * 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. */ #include #include #include #include #include "common.h" void __init shmobile_init_delay(void) { struct device_node *np, *cpus; u32 max_freq = 0; cpus = of_find_node_by_path("/cpus"); if (!cpus) return; for_each_child_of_node(cpus, np) { u32 freq; if (IS_ENABLED(CONFIG_ARM_ARCH_TIMER) && (of_device_is_compatible(np, "arm,cortex-a7") || of_device_is_compatible(np, "arm,cortex-a15"))) { of_node_put(np); of_node_put(cpus); return; } if (!of_property_read_u32(np, "clock-frequency", &freq)) max_freq = max(max_freq, freq); } of_node_put(cpus); if (!max_freq) return; /* * Calculate a worst-case loops-per-jiffy value * based on maximum cpu core hz setting and the * __delay() implementation in arch/arm/lib/delay.S. * * This will result in a longer delay than expected * when the cpu core runs on lower frequencies. */ if (!preset_lpj) preset_lpj = max_freq / HZ; }