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Add WC support for arm64 in the ENA driver

Authored by on Oct 8 2019, 7:21 AM.



As the pmamp_change_attr() is public on arm64 since D20787, it can be
used on the arm64 to map memory range as with the write combined

It requires the driver to use generic VM_MEMATTR_WRITE_COMBINING flag
instead of the x86 specific PAT_WRITE_COMBINING.

Submitted by: Michal Krawczyk <>
Obtained from: Semihalf
Sponsored by: Amazon, Inc.

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rS FreeBSD src repository
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Event Timeline created this revision.Oct 8 2019, 7:21 AM

The pmap_change_attr() API is private on arm64

It hasn't been private since D20787 landed! (Was required for GPU drivers.) edited the summary of this revision. (Show Details)

Due to pmap_change_attr() being public on arm64, the patch was reworked to use it instead

This revision was not accepted when it landed; it landed in state Needs Review.Oct 31 2019, 3:38 PM
This revision was automatically updated to reflect the committed changes.