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From: Vidya Sagar <vidyas@nvidia.com>
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Subject: [PATCH V2 1/2] dt-bindings: Add PCIe "preserve-boot-config" property
Date: Wed, 10 Jan 2024 08:37:24 +0530
Message-ID: <20240110030725.710547-2-vidyas@nvidia.com>
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The existing "linux,pci-probe-only" property applies at a system level
and it is not possible to selectively convey individual host bridge's
requirement w.r.t preserving the boot configuration done by the platform
firmware to the kernel. "preserve-boot-config" addresses that concern
and can be used to preserve the boot configuration for host bridges
selectivey.

Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
---
V2:
* None

 Documentation/devicetree/bindings/pci/pci.txt | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Documentation/devicetree/bindings/pci/pci.txt b/Documentation/devicetree/bindings/pci/pci.txt
index 6a8f2874a24d..0a5ff998cbe8 100644
--- a/Documentation/devicetree/bindings/pci/pci.txt
+++ b/Documentation/devicetree/bindings/pci/pci.txt
@@ -32,6 +32,10 @@ driver implementation may support the following properties:
    root port to downstream device and host bridge drivers can do programming
    which depends on CLKREQ signal existence. For example, programming root port
    not to advertise ASPM L1 Sub-States support if there is no CLKREQ signal.
+- preserve-boot-config:
+   If present this property specifies that this host bridge is already
+   configured by the platform firmware and the OS doesn't need to reconfigure
+   it again.
 
 PCI-PCI Bridge properties
 -------------------------
-- 
2.25.1