Handle MIPS32 cycle counter overflow #292
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Thanks to `mipsel-openwrt-linux-g++ ... -dM -E - <<< '' | grep -i MIPS`
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Unfortunately, 32-bit cycle counter overflows ≈ twice a minute, so some code is needed to distinguish between meaningful overflow (just add
1<<32and get the result) and hardly-meaningful (do some math to get the result).The code might be extended to get rid of
timer_infaltogether, but it needs clock counter frequency accounting at a timer level and I'm somewhat reluctant to implementing that as this code seems to be good enough.