atapibasedevice: Clear BSY and signal interrupt on unsupported ATA command - #206
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Looks good. My only say about this is that the two changes should be separate commits. |
…mmand The default case in perform_command() set the ABRT/ERR flags but left BSY asserted and never fired the interrupt. Open Firmware therefore hung waiting on the ATAPI CD-ROM after issuing commands it does not support (e.g. 0xEC IDENTIFY_DEVICE during the boot device probe).
Move the Page 0x31 getter from ScsiCdrom into ScsiCdromCmds so it is also registered for the ATAPI CD-ROM, which Mac OS queries via MODE_SENSE.
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That was quick. Thanks! |
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Summary
The ATAPI CD-ROM hung Open Firmware during device probing on the Power Mac G3 beige, leaving a grey screen with a cursor after the 3rd display extension init.
Root cause
AtapiBaseDevice::perform_command()default case set the ABRT/ERR bits but leftBSYasserted and never fired the interrupt. When Open Firmware issued an unsupported ATA command during its boot device probe (0xEC IDENTIFY_DEVICE), the device stayed busy forever and the machine never progressed past probing the CD-ROM.Changes
BSYand callupdate_intrq(1)so the host receives a proper error status and can continue, matching the other command paths and the behavior inAtaHardDisk.ScsiCdromintoScsiCdromCmdsso it is registered for the ATAPI CD-ROM as well as the SCSI one. The Mac OS driver requests this page on device errors; the ATAPI path previously replied "page not supported".Verification
Booting Mac OS 9.2.2 from the install CD on the Power Mac G3 beige with a 256 MB RAM bank now proceeds past the point where it previously hung. No compiler warnings.