On Wed, May 14, 2025 at 1:33 PM David (Ming Qiang) Wu <[email protected]> wrote: > > Similar to the changes made for VCN v4.0.5, the addition of register > read-back support in other VCN versions is intended to prevent potential > race conditions, even though such issues have not been observed yet. > This change ensures consistency across different VCN variants and helps > avoid similar issues. The overhead introduced is negligible. >
Just for some background this is standard PCI MMIO behavior. If you want to guarantee that the writes hit the hardware, you need to do a read to post the writes. You only need to do it for cases where you care about the writes posting before the next operation. Alex
