Legacy VGA & VBE interface as a common interface is supported by
many legacy and modern OS. Many installer of OS distribution use
this interface to display the GUI of installer when setup a refresh
new installation on bare-metal. Besides, Windows OS always use this
interface to display it's BSOD, recovery mode & safe mode GUI. It
is need because Windows don't include virtio-gpu driver as their
in-box driver, VGA interface will be used before the virtio-gpu
driver been installed.
To be compatiable with the PCI bar layout of legacy VGA, the layout
is refined to meet with the requirement of legacy VGA and modern
virtio-gpu.
BAR0: VGA Framebuffer memory, 16 MB in size.
BAR2: MMIO Space
[0x0000~0x03ff] EDID data blob
[0x0400~0x041f] VGA ioports registers
[0x0500~0x0516] bochs display interface registers
[0x1000~0x17ff] Virtio common configuration registers
[0x1800~0x1fff] Virtio ISR state registers
[0x2000~0x2fff] Virtio device configuration registers
[0x3000~0x3fff] Virtio notification registers
BAR4: MSI/MSI-X
BAR5: Virtio port io
Tracked-On: #7210
Signed-off-by: Sun Peng <peng.p.sun@linux.intel.com>
Reviewed-by: Zhao, yakui <yakui.zhao@intel.com>
Acked-by: Wang, Yu1 <yu1.wang@intel.com>
Sun, Peng