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charset=UTF-8 Content-Transfer-Encoding: 7bit X-purgate-ID: tlsNG-16d1c6/1788246726-1F2C677B-4D01AA2D/0/0 X-purgate-type: clean X-purgate-size: 908 On 27.08.2026 17:20, Oleksii Kurochko wrote: > vstimecmp is a 64-bit CSR independently of XLEN, which is why it is > written with csr_write64(). On RV32 that macro splits the value into > the vstimecmp/vstimecmph pair, so passing ULONG_MAX (0xffffffff there) > writes all ones to the low half and zero to the high half, leaving the > CSR at 0x00000000ffffffff rather than at its maximum. A VS-timer irq > would then become pending as soon as (time + htimedelta) reaches 2^32, > which is exactly what the code is trying to avoid. > > Use UINT64_MAX, which matches the width of the CSR. On RV64 it is equal > to ULONG_MAX, so no functional change there. Hmm. This again is an example where code (likely) will be silently wrong for RV128. Presumably the CSR would be XLEN bits wide there as well, and hence you'd need to write it with 128 bits of ones. Imo ~0 is what wants using here. Jan