arno/linux-insides
1
0
Fork 0
mirror of https://github.com/0xAX/linux-insides.git synced 2024-12-22 06:38:07 +00:00
Code Issues Releases Wiki Activity

Update linux-bootstrap-1.md

Browse Source
This commit is contained in:
Z 2020-11-20 09:39:30 +08:00 committed by GitHub
parent ff558bcccd
commit cdc7d9421c
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
Booting/linux-bootstrap-1.md
View File

@ -64,7 +64,7 @@ which is `65520` bytes past the first megabyte. Since only one megabyte is acces
Ok, now we know a little bit about real mode and its memory addressing. Let's get back to discussing register values after reset.
The `CS` register consists of two parts: the visible segment selector and the hidden base address. While the base address is normally formed by multiplying the segment selector value by 16, during a hardware reset the segment selector in the CS register is loaded with `0xf000` and the base address is loaded with `0xffff0000`. The processor uses this special base address until `CS` changes.
The `CS` register consists of two parts: the visible segment selector and the hidden base address. In real-address mode, the base address is normally formed by shifting the 16-bit segment selector value 4 bits to the left to produce a 20-bit base address. However, during a hardware reset the segment selector in the CS register is loaded with `0xf000` and the base address is loaded with `0xffff0000`. The processor uses this special base address until `CS` changes.
The starting address is formed by adding the base address to the value in the EIP register: