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AHCI: Difference between revisions
→AHCI port memory space initialization
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Before rebasing Port memory space, OS must wait for current pending commands to finish and tell HBA to stop receiving FIS from the port. Otherwise an accidently incoming FIS may be written into a partially configured memory area. This is done by checking and setting corresponding bits at the Port Command And Status register (HBA_PORT.cmd). The example subroutines stop_cmd() and start_cmd() do the job.
The following example assumes that the HBA has 32 ports implemented and each port contains 32 command slots, and will allocate 8 PRDTs for each command slot. (Note: unlike in the above struct definitions, this is using 8 instead of 1)
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