From 70c202c480b8dadd27dbfb723f0cede1fb0e0d0c Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Tue, 22 Sep 2020 12:45:40 -0600 Subject: x86: Add a way to add to the e820 memory table Some boards want to reserve extra regions of memory. Add a 'chosen' property to support this. Signed-off-by: Simon Glass Reviewed-by: Bin Meng --- doc/device-tree-bindings/chosen.txt | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'doc') diff --git a/doc/device-tree-bindings/chosen.txt b/doc/device-tree-bindings/chosen.txt index d4dfc05847..e5ba6720ce 100644 --- a/doc/device-tree-bindings/chosen.txt +++ b/doc/device-tree-bindings/chosen.txt @@ -143,3 +143,21 @@ This provides the ordering to use when writing device data to the ACPI SSDT node to add. The ACPI information is written in this order. If the ordering does not include all nodes, an error is generated. + +e820-entries +------------ + +This provides a way to add entries to the e820 table which tells the OS about +the memory map. The property contains three sets of 64-bit values: + + address - Start address of region + size - Size of region + flags - Flags (E820_...) + +Example: + +chosen { + e820-entries = /bits/ 64 < + IOMAP_P2SB_BAR IOMAP P2SB_SIZE E820_RESERVED + MCH_BASE_ADDRESS MCH_SIZE E820_RESERVED>; +}; -- cgit v1.2.3