CVS commit: src/sys/dev/ic

Module Name:	src
Committed By:	thorpej
Date:		Sun Jul 12 20:58:00 UTC 2026

Modified Files:
	src/sys/dev/ic: wdc.c

Log Message:
Support 8-bit PIO if the front-end indicates that it's necessary:
- In wdc_drvprobe(), if neither ATAC_CAP_DATA16 nor ATAC_CAP_DATA32
  is set in the controller capabilities, then attempt to enable 8-bit
  PIO on the drive.  If that command fails, ignore the drive.
- In wdc_datain_pio(), if we're doing 8-bit PIO, check for ATA_DRIVE_NOSTREAM
  and simulate a NOSTREAM 16-bit PIO.  This is necessary because we
  treat the IDENTIFY command as "special" for historical (and almost
  certainly bad) reasons.
- wdc_dataout_pio() gets the same NOSTREAM shenanigans for 8-bit PIO,
  although I would be surprised if it is ever requested.


To generate a diff of this commit:
cvs rdiff -u -r1.314 -r1.315 src/sys/dev/ic/wdc.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.