fork of 9front i guess
![]() on some modern machines like the x250, the bios arranges the mtrr's and the framebuffer membar in a way that doesnt allow us to mark the framebuffer pages as write combining, leading to slow graphics. since the pentium III, the processor interprets the page table bit combinations of the WT, CD and bit7 bits as an index into the page attribute table (PAT). to not change the semantics of the WT and CD bits, we preserve the bit patterns 0-3 and use the last entry 7 for write combining. (done in mmuinit() for each core). the new patwc() function takes virtual address range and changes the page table marking the range as write combining. no attempt is made on invalidating tlb's. doesnt matter in our case as the following mtrr() call in screen.c does it for us. |
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386 | ||
68000 | ||
68020 | ||
acme | ||
adm/timezone | ||
amd64 | ||
arm | ||
lib | ||
mips | ||
power | ||
power64 | ||
rc | ||
sparc | ||
sparc64 | ||
spim | ||
sys | ||
.hgignore |