From f290f223449767c6a6bcad4c1980c5ef4d12d324 Mon Sep 17 00:00:00 2001 From: Sainath Grandhi Date: Mon, 13 Apr 2020 17:48:02 -0700 Subject: [PATCH] doc: Known Limitation regarding PCI devices and resources assignment ACRN assumes certain state for the PCI devices w.r.t. resources assigned to them before the platform BIOS hands control over to itself. When the same BIOS is used with native OS boot, there should not be a need for native kernel to re-program device BARs or bridge windows for bridge devices. Signed-off-by: Sainath Grandhi --- doc/reference/hardware.rst | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/doc/reference/hardware.rst b/doc/reference/hardware.rst index 8a4ef573e..7b8ad7a68 100644 --- a/doc/reference/hardware.rst +++ b/doc/reference/hardware.rst @@ -27,6 +27,15 @@ Known Limitations ***************** Platforms with multiple PCI segments +ACRN assumes the following conditions are satisfied from the Platform BIOS + +* All the PCI device BARs should be assigned resources, including SR-IOv VF BARs if a device supports. + +* Bridge windows for PCI bridge devices and the resources for root bus, should be programmed with values + that enclose resources used by all the downstream devices. + +* There should be no conflict in resources among the PCI devices and also between PCI devices and other platform devices. + Verified Platforms According to ACRN Usage ******************************************