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* Remove empty security.md * Remove second H1 header from lib/index.md * Move two documents in appropriate subfolders * Fix file path * Drop document overview Change-Id: I0e9df6203e82003c01b84967ea6bd779d7583fef Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/32340 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net> Reviewed-by: Hung-Te Lin <hungte@chromium.org> Reviewed-by: Martin Roth <martinroth@google.com>
26 lines
1.2 KiB
Markdown
26 lines
1.2 KiB
Markdown
# ABI data consumption
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This text describes the ABI coreboot presents to downstream users. Such
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users are payloads and/or operating systems. Therefore, this text serves
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at what can be relied on for downstream consumption. Anything not explicitly
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listed as consumable is subject to change without notice.
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## Background and Usage
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coreboot passes information to downstream users using coreboot tables. These
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table definitions can be found in
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`./src/commonlib/include/commonlib/coreboot_tables.h` and
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`./payloads/libpayload/include/coreboot_tables.h` respectively within coreboot
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and libpayload. One of the most vital and important pieces of information
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found within these tables is the memory map of the system indicating
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available and reserved memory.
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In 2009 cbmem was added to coreboot. The "CBMEM high table memory manager"
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serves a way for coreboot to bookkeep its own internal data. While some
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of this data may be exposed through the coreboot tables the data structures
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used to manage the data within the cbmem area is subject to change.
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Provided the above, if one needs a piece of data exposed to the OS
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or payload it should reside within the coreboot tables. If it isn't there
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then a code change will be required to add it to the coreboot tables.
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