| 1 | // SPDX-License-Identifier: GPL-2.0 |
|---|---|
| 2 | /* |
| 3 | * SH-Mobile Timer |
| 4 | * |
| 5 | * Copyright (C) 2010 Magnus Damm |
| 6 | * Copyright (C) 2002 - 2009 Paul Mundt |
| 7 | */ |
| 8 | #include <linux/platform_device.h> |
| 9 | #include <linux/clocksource.h> |
| 10 | #include <linux/delay.h> |
| 11 | #include <linux/of_address.h> |
| 12 | |
| 13 | #include "common.h" |
| 14 | |
| 15 | void __init shmobile_init_delay(void) |
| 16 | { |
| 17 | struct device_node *np; |
| 18 | u32 max_freq = 0; |
| 19 | |
| 20 | for_each_of_cpu_node(np) { |
| 21 | u32 freq; |
| 22 | |
| 23 | if (!of_property_read_u32(np, propname: "clock-frequency", out_value: &freq)) |
| 24 | max_freq = max(max_freq, freq); |
| 25 | } |
| 26 | |
| 27 | if (!max_freq) |
| 28 | return; |
| 29 | |
| 30 | /* |
| 31 | * Calculate a worst-case loops-per-jiffy value |
| 32 | * based on maximum cpu core hz setting and the |
| 33 | * __delay() implementation in arch/arm/lib/delay.S. |
| 34 | * |
| 35 | * This will result in a longer delay than expected |
| 36 | * when the cpu core runs on lower frequencies. |
| 37 | */ |
| 38 | |
| 39 | if (!preset_lpj) |
| 40 | preset_lpj = max_freq / HZ; |
| 41 | } |
| 42 |