Now I am reading intel northbridge 440BX spec(look page 88:Memory System Address Space)
And i have a box with 440BX
I look /proc/iomem,i find that Framebuffer's size is 16MB(i open vesa before kernel using vga=788)
And the local Graphics Memory's size is 64MB(through PMBASE Reg (24h) ;Dev 1(that's pci bridge)) to PMBASE Reg(26h);Dev 1).
the rest is Rendering Buffer,Depth Buffer,and Video Capture Buffer.
I want to ask :
the rest 48M buffer is really located in display card?
OS(like kernel) can manipulate framebuffer through mapping the buffer to Virtual Memory.
But Can OS manipulate the rest buffer directly,or only Graphics card can do so?
