28 строки
636 Б
Go
28 строки
636 Б
Go
// +build k210,!qemu
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package runtime
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import (
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"device/riscv"
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)
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// ticksToNanoseconds converts CPU ticks to nanoseconds.
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func ticksToNanoseconds(ticks timeUnit) int64 {
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// The following calculation is actually the following, but with both sides
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// reduced to reduce the risk of overflow:
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// ticks * 1e9 / (390000000 / 50)
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// 50 is the CLINT divider and 390000000 is the CPU frequency.
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return int64(ticks) * 5000 / 39
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}
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// nanosecondsToTicks converts nanoseconds to CPU ticks.
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func nanosecondsToTicks(ns int64) timeUnit {
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return timeUnit(ns * 39 / 5000)
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}
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func abort() {
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// lock up forever
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for {
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riscv.Asm("wfi")
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}
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}
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