tinygo/src/runtime/runtime_cortexm_qemu.go

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1,3 КиБ
Go

//go:build cortexm && qemu
// +build cortexm,qemu
package runtime
// This file implements the Stellaris LM3S6965 Cortex-M3 chip as implemented by
// QEMU.
import (
"device/arm"
"runtime/volatile"
"unsafe"
)
type timeUnit int64
var timestamp timeUnit
//export Reset_Handler
func main() {
preinit()
run()
// Signal successful exit.
exit(0)
}
func ticksToNanoseconds(ticks timeUnit) int64 {
return int64(ticks)
}
func nanosecondsToTicks(ns int64) timeUnit {
return timeUnit(ns)
}
func sleepTicks(d timeUnit) {
// TODO: actually sleep here for the given time.
timestamp += d
}
func ticks() timeUnit {
return timestamp
}
// UART0 output register.
var stdoutWrite = (*volatile.Register8)(unsafe.Pointer(uintptr(0x4000c000)))
func putchar(c byte) {
stdoutWrite.Set(uint8(c))
}
func getchar() byte {
// dummy, TODO
return 0
}
func buffered() int {
// dummy, TODO
return 0
}
func waitForEvents() {
arm.Asm("wfe")
}
func abort() {
exit(1)
}
func exit(code int) {
// Exit QEMU.
if code == 0 {
arm.SemihostingCall(arm.SemihostingReportException, arm.SemihostingApplicationExit)
} else {
arm.SemihostingCall(arm.SemihostingReportException, arm.SemihostingRunTimeErrorUnknown)
}
// Lock up forever (should be unreachable).
for {
arm.Asm("wfi")
}
}