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Published 20 hours ago • verified publisher icon tianocore

Reserve ecam v express

Open vbpandya opened this issue 10 months ago • 1 comments

Platform/Arm/VExpressPkg: Reserve the ECAM area in ACPI with RES0 device

Add a RES0 device to the SSDT to reserve the PCI ECAM area.This fixes the firmware bug reported by Linux:

acpi PNP0A08:00: [Firmware Bug]: ECAM area [mem 0x40000000-0x4fffffff]not reserved in ACPI namespace

With this change, the above message is replaced with:

acpi PNP0A08:00: ECAM area [mem 0x40000000-0x4fffffff] reserved by PNP0C02:00

This patch is based on commit 1e5be97660c6 ("Platform/ARM/JunoPkg:Reserve the ECAM area in ACPI with RES0 device")

REF:https://developer.arm.com/documentation/100964/1127/Base-Platform/Base-Platform-memory/Base-Platform-memory-map?lang=en

Also use same PCD for Juno and VExpress.

vbpandya avatar Jan 21 '25 11:01 vbpandya

@samimujawar can you please take a look at this PR ?

vbpandya avatar Mar 03 '25 09:03 vbpandya

@vbpandya any update on the status of this PR?

samimujawar avatar Aug 14 '25 23:08 samimujawar

@vbpandya any update on the status of this PR?

This one slipped through the cracks, in the mean time FVP has moved to Dynamic table (makes implementing your feedback easy) which Juno is still on static tables, will close this PR for now, since it will be good to move Juno to Dynamic Table and then use common PCD for both platforms.

vbpandya avatar Aug 18 '25 10:08 vbpandya

I think we should drop the static tables support and keep Dynamic Tables Framework based support only for Juno. Can you send a separate PR for that, please?

Also, I think the SSDT PCIe generator may be taking care of the Firmware bug issue which the Linux kernel reports. Can you check and report back, please? In that case this PR can be closed.

samimujawar avatar Aug 19 '25 02:08 samimujawar