readme

readme.md

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+## Overview
+Currently we boot from BIOS on a GPT-partitioned disk.
+
+`boot0.s` is the first-stage bootloader. It lives in the MBR bootstrap field, and must therefore
+fit into 440 bytes. Its tasks are:
+- [x] Set up a stack etc.
+- [x] Get the boot drive geometry
+- [x] Load and parse the GPT
+- [x] Find the partition of the second stage
+- [x] Load and jump to the first sector of the second stage
+
+`boot1.s` is the second-stage bootloader. Its tasks are:
+- [x] Load its own sectors not loaded by the first stage
+- [ ] Enable A20
+- [ ] Detect available memory
+- [ ] Enter unreal mode
+- [ ] Read the kernel ELF from disk (don't have to parse the ELF just yet)
+- [ ] Get all the useful information we can from the BIOS before we leave unreal mode
+- [ ] Enter long mode (possibly via protected mode?)
+- [ ] Load the kernel ELF
+- [ ] Initialise stack etc. for the kernel
+- [ ] Jump to kernel