HP van Braam on Nostr: I spend a bit of time dissecting the #sunpci driver in #ghidra. And I can now boot ...
I spend a bit of time dissecting the #sunpci driver in #ghidra. And I can now boot the SunPCi from my own code! Using the #solaris driver still.
Some terrifying conclusions:
The windowed output in the SunPCi userspace application comes from repeatedly read()ing the /dev/sunpcidrv0 node. That just returns some raw video data and mode information.
Userspace contains a VGA emulator itself. Whenever it doesn't understand something it just switches to the external VGA.
#retrocomputing
Published at
2025-12-06 17:28:08 UTCEvent JSON
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"content": "I spend a bit of time dissecting the #sunpci driver in #ghidra. And I can now boot the SunPCi from my own code! Using the #solaris driver still.\n\nSome terrifying conclusions:\n\nThe windowed output in the SunPCi userspace application comes from repeatedly read()ing the /dev/sunpcidrv0 node. That just returns some raw video data and mode information.\n\nUserspace contains a VGA emulator itself. Whenever it doesn't understand something it just switches to the external VGA.\n\n#retrocomputing\n\nhttps://mastodon.tmm.cx/system/media_attachments/files/115/673/796/775/238/599/original/5d22ec049a6e27c6.png",
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