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Diffstat (limited to 'arch/arm/mach-shmobile/timer.c')
-rw-r--r-- | arch/arm/mach-shmobile/timer.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/arch/arm/mach-shmobile/timer.c b/arch/arm/mach-shmobile/timer.c new file mode 100644 index 0000000000..2335311b5f --- /dev/null +++ b/arch/arm/mach-shmobile/timer.c @@ -0,0 +1,41 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * SH-Mobile Timer + * + * Copyright (C) 2010 Magnus Damm + * Copyright (C) 2002 - 2009 Paul Mundt + */ +#include <linux/platform_device.h> +#include <linux/clocksource.h> +#include <linux/delay.h> +#include <linux/of_address.h> + +#include "common.h" + +void __init shmobile_init_delay(void) +{ + struct device_node *np; + u32 max_freq = 0; + + for_each_of_cpu_node(np) { + u32 freq; + + if (!of_property_read_u32(np, "clock-frequency", &freq)) + max_freq = max(max_freq, freq); + } + + 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; +} |