34 строки
786 Б
Go
34 строки
786 Б
Go
//go:build fe310 && !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 RTC ticks (at 32768Hz) 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 / 32768
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return int64(ticks) * 1953125 / 64
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}
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// nanosecondsToTicks converts nanoseconds to RTC ticks (running at 32768Hz).
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func nanosecondsToTicks(ns int64) timeUnit {
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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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// ns * 32768 / 1e9
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return timeUnit(ns * 64 / 1953125)
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}
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func exit(code int) {
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abort()
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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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