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| author | Aaron Durbin <adurbin@chromium.org> | 2013-02-08 17:28:04 -0600 |
|---|---|---|
| committer | Stefan Reinauer <stefan.reinauer@coreboot.org> | 2013-03-21 22:28:28 +0100 |
| commit | 8e4a355773cc64a89b3fc4d79981cfb02bda7e66 (patch) | |
| tree | 01a9e6d5fc66568fd5c318e5edf17d47e73f65e8 /src/Kconfig | |
| parent | 43e4a80a92bf00540e4d9b0734eb53f32044226f (diff) | |
| download | coreboot-8e4a355773cc64a89b3fc4d79981cfb02bda7e66.tar.xz | |
coreboot: introduce CONFIG_RELOCATABLE_RAMSTAGE
This patch adds an option to build the ramstage as a reloctable binary.
It uses the rmodule library for the relocation. The main changes
consist of the following:
1. The ramstage is loaded just under the cmbem space.
2. Payloads cannot be loaded over where ramstage is loaded. If a payload
is attempted to load where the relocatable ramstage resides the load
is aborted.
3. The memory occupied by the ramstage is reserved from the OS's usage
using the romstage_handoff structure stored in cbmem. This region is
communicated to ramstage by an CBMEM_ID_ROMSTAGE_INFO entry in cbmem.
4. There is no need to reserve cbmem space for the OS controlled memory for
the resume path because the ramsage region has been reserved in #3.
5. Since no memory needs to be preserved in the wake path, the loading
and begin of execution of a elf payload is straight forward.
Change-Id: Ia66cf1be65c29fa25ca7bd9ea6c8f11d7eee05f5
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/2792
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@google.com>
Diffstat (limited to 'src/Kconfig')
| -rw-r--r-- | src/Kconfig | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/src/Kconfig b/src/Kconfig index f6a83e8a85..7a8985ce0f 100644 --- a/src/Kconfig +++ b/src/Kconfig @@ -307,7 +307,14 @@ config HAVE_INIT_TIMER config HIGH_SCRATCH_MEMORY_SIZE hex + default 0x5000 if RELOCATABLE_RAMSTAGE default 0x0 + help + The amount of extra memory to reserve from the OS. If + RELOCATABLE_RAMSTAGE is enabled a size of 20KiB is reserved. This is + for the use of a stack in romstage after memory has been initialized. + The stack size required in romstage can be large when needing to + decompress the ramstage. config USE_OPTION_TABLE bool @@ -374,6 +381,17 @@ config RELOCATABLE_MODULES building relocatable modules in the ram stage. Those modules can be loaded anywhere and all the relocations are handled automatically. +config RELOCATABLE_RAMSTAGE + depends on RELOCATABLE_MODULES + bool "Build the ramstage to be relocatable in 32-bit address space." + default n + help + The reloctable ramstage support allows for the ramstage to be built + as a relocatable module. The stage loader can identify a place + out of the OS way so that copying memory is unnecessary during an S3 + wake. When selecting this option the romstage is responsible for + determing a stack location to use for loading the ramstage. + config HAVE_ACPI_TABLES bool help |