diff options
Diffstat (limited to 'cpu/features/optional/segmented_paging/structures.txt')
| -rw-r--r-- | cpu/features/optional/segmented_paging/structures.txt | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/cpu/features/optional/segmented_paging/structures.txt b/cpu/features/optional/segmented_paging/structures.txt new file mode 100644 index 0000000..d7de77b --- /dev/null +++ b/cpu/features/optional/segmented_paging/structures.txt @@ -0,0 +1,25 @@ +TODO: Assign bit in FR + +Offset: 9 + (n/16) + +Replaces the offset field in the gdt with the following: + Width: half the number of bits for the current mode + Value: pointer to array of chunks, physical address + +Array of chunks: + Width: half the number of bits for the current mode + + Value: + Upper (n - offset) bits: + Pointer to physical address >> offset + Lowest bit: + Present + Remaining bits: + Unused by this system + + + Each value in the array represents 1 << offset bytes of memory. + Physical address is calculated from a reference such that: + Physical address = (gdt[segment].chunks[addr>>offset].address << offset) | (lowest offset bits of addr) + + Triggers a page fault if the present bit is not set |