mb/emulation/qemu-q35,qemu-i440fx: Add x86_64 support

* Enable optional x86_64 romstage, postcar and ramstage
* Add Kconfig for x86_64 compilation
* Add documentation for x86 qemu mainboards
* Increase CAR stack as x86_64 uses more than 0x4000 bytes

Working:
* Boots to Linux
* Boots to SeaBIOS
* Drops to protected mode at end of ramstage
* Enumerates PCI devices
* Relocateable ramstage
* SMM

Change-Id: If2f02a95b2f91ab51043d4e81054354f4a6eb5d5
Signed-off-by: Patrick Rudolph <siro@das-labor.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/29667
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
This commit is contained in:
Patrick Rudolph
2018-11-15 13:42:15 +01:00
committed by Patrick Rudolph
parent e3dd57e106
commit 57907fcebf
5 changed files with 165 additions and 19 deletions

View File

@@ -5,10 +5,11 @@ This section contains documentation about coreboot on x86 architecture.
* [x86 PAE support](pae.md)
## State of x86_64 support
At the moment there's no single board that supports x86_64 or to be exact
`ARCH_RAMSTAGE_X86_64` and `ARCH_ROMSTAGE_X86_64`.
At the moment there's only experimental x86_64 support.
The `emulation/qemu-i440fx` and `emulation/qemu-q35` boards do support
*ARCH_RAMSTAGE_X86_64* , *ARCH_POSTCAR_X86_64* and *ARCH_ROMSTAGE_X86_64*.
In order to add support for x86_64 the following assumptions are made:
In order to add support for x86_64 the following assumptions were made:
* The CPU supports long mode
* All memory returned by malloc must be below 4GiB in physical memory
* All code that is to be run must be below 4GiB in physical memory
@@ -39,18 +40,16 @@ The page tables contains the following structure:
At the moment *$n* is 4, which results in identity mapping the lower 4 GiB.
## Steps to add basic support for x86_64
* Add x86_64 toolchain support - *DONE*
* Fix compilation errors - *DONE*
* Fix linker errors - *TODO*
* Add x86_64 rmodule support - *DONE*
* Add x86_64 exception handlers - *DONE*
* Setup page tables for long mode - *DONE*
* Add assembly code for long mode - *DONE*
* Add assembly code for SMM - *DONE*
* Add assembly code for postcar stage - *DONE*
* Add assembly code to return to protected mode - *DONE*
* Implement reference code for mainboard `emulation/qemu-q35` - *TODO*
## Basic x86_64 support
Basic support for x86_64 has been implemented for QEMU mainboard target.
## Reference implementation
The reference implementation is
* [QEMU i440fx](../../mainboard/emulation/qemu-i440fx.md)
* [QEMU Q35](../../mainboard/emulation/qemu-q35.md)
## TODO
* Identity map memory above 4GiB in ramstage
## Future work