28 строки
483 Б
Go
28 строки
483 Б
Go
//go:build stm32 && !(stm32f103 || stm32l0x1)
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package machine
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import "device/stm32"
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var rngInitDone = false
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const RNG_MAX_READ_RETRIES = 1000
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// GetRNG returns 32 bits of cryptographically secure random data
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func GetRNG() (uint32, error) {
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if !rngInitDone {
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initRNG()
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rngInitDone = true
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}
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cnt := RNG_MAX_READ_RETRIES
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for !stm32.RNG.SR.HasBits(stm32.RNG_SR_DRDY) {
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cnt--
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if cnt == 0 {
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return 0, ErrTimeoutRNG
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}
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}
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ret := stm32.RNG.DR.Get()
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return ret, nil
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}
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