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riscv-non-isa / riscv-iommu

RISC-V IOMMU Specification
https://jira.riscv.org/browse/RVG-55
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msi_address_translation #428

Closed asdvvcc123 closed 3 weeks ago

asdvvcc123 commented 3 weeks ago

hi，sir:

  1. in msi_address_translation , iotval2 is never be set ; but in spec no place metion need to record gpa on msi transtion process or not ; image

  1. here i think 52 is ok ; image

thanks!

ved-rivos commented 3 weeks ago

The spec states:

If the CAUSE is a guest-page fault then bits 63:2 of the zero-extended guest-physical-address are reported in iotval2[63:2]. If bit 0 of iotval2 is 1, then the guest-page-fault was caused by an implicit memory access for first-stage address translation. If bit 0 of iotval2 is 1, and the implicit access was a write then bit 1 of iotval2 is set to 1 else it is set to 0.

iotval2 is not reported for any other cause code.

here i think 52 is ok

Yes. 52 would suffice since the data and mask are pre-shifted by 12 bits but this code is not wrong as the high order 12 bits in mask will be always 0.

asdvvcc123 commented 3 weeks ago

thanks,get it