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Add location coreboot source code

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Andrés Rojas Guerrero 2017-10-18 16:25:21 +02:00
parent 2b43267b23
commit 311a318f58
1 changed files with 2 additions and 2 deletions
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Booting/linux-bootstrap-1.md
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@ -73,7 +73,7 @@ The starting address is formed by adding the base address to the value in the EI
'0xfffffff0' '0xfffffff0'
``` ```
We get `0xfffffff0`, which is 16 bytes below 4GB. This point is called the [Reset vector](http://en.wikipedia.org/wiki/Reset_vector). This is the memory location at which the CPU expects to find the first instruction to execute after reset. It contains a [jump](http://en.wikipedia.org/wiki/JMP_%28x86_instruction%29) (`jmp`) instruction that usually points to the BIOS entry point. For example, if we look in the [coreboot](http://www.coreboot.org/) source code, we will see: We get `0xfffffff0`, which is 16 bytes below 4GB. This point is called the [Reset vector](http://en.wikipedia.org/wiki/Reset_vector). This is the memory location at which the CPU expects to find the first instruction to execute after reset. It contains a [jump](http://en.wikipedia.org/wiki/JMP_%28x86_instruction%29) (`jmp`) instruction that usually points to the BIOS entry point. For example, if we look in the [coreboot](http://www.coreboot.org/) source code (src/cpu/x86/16bit/reset16.inc), we will see:
```assembly ```assembly
.section ".reset" .section ".reset"
@ -87,7 +87,7 @@ reset_vector:
Here we can see the `jmp` instruction [opcode](http://ref.x86asm.net/coder32.html#xE9), which is `0xe9`, and its destination address at `_start - ( . + 2)`. Here we can see the `jmp` instruction [opcode](http://ref.x86asm.net/coder32.html#xE9), which is `0xe9`, and its destination address at `_start - ( . + 2)`.
We can also see that the `reset` section is `16` bytes and that is compiled to start from `0xfffffff0` address: We can also see that the `reset` section is `16` bytes and that is compiled to start from `0xfffffff0` address (src/cpu/x86/16bit/reset16.lds):
``` ```
SECTIONS { SECTIONS {