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Contents 1 Single PCI card multiple outputs 2 Summary 3 Owner 4 Current Status 5 Description 5.1 Rational 5.2 Requirements

Single PCI card multiple outputs

Summary

Teach qemu's qxl device to provide multiple outputs.

Owner

• Alon Levy

Current Status

• Targeted Release: None yet
• 0% complete
• https://bugzilla.redhat.com/show_bug.cgi?id=770842

Description

Rational

We currently use four different PCI cards to enable four monitors output. This has a few limitations:

• Requires our X driver to support Xinerama instead of RandR (or alternatively teach RandR to work with multiple PCI cards)
• Takes more then one PCI slot (as we don't support multifunction=on, so this is a real problem)
• Fragments the PCI BARs,
  • instead of: 256MB devram, 256MB vram
  • or even: 196MB devram, 196MB vram (due to 99%_limit(4) == 196, while 99%_limit(1) * 4 = 256).
  • we have: [64,64,64,64] devram, [64,64,64,64] vram

Requirements

• Backward compatible - all existing drivers still works.
• Initially do static allocation, i.e. -device qxl,monitors=4
• Later dynamically:
  • cards have support for reporting inserted jacks. Is there support for creating jacks on the fly (XDDM/WDDM/X&Linux) ?