From b77001b8ef3f7dcea3128dfe3a48fcdd67b9421b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Kope=C4=87?= <michal.kopec@3mdeb.com>
Date: Thu, 2 May 2024 13:21:01 +0200
Subject: [PATCH] UefiPayloadPkg/GraphicsOutputDxe: accept framebuffer BAR
 offsets
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Some platforms place the linear framebuffer at an offset within the PCI
BAR (for example, Meteor Lake can use BAR2 + 0x800000). The existing
GraphicsOutputDxe validation requires the framebuffer base to match the
BAR base exactly, which rejects these configurations.

Relax the check to accept a framebuffer base within the BAR window, and
use the provided framebuffer base address when it falls within that
range.

Signed-off-by: Michał Kopeć <michal.kopec@3mdeb.com>
Signed-off-by: Sean Rhodes <sean@starlabs.systems>
---
 UefiPayloadPkg/GraphicsOutputDxe/GraphicsOutput.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/UefiPayloadPkg/GraphicsOutputDxe/GraphicsOutput.c b/UefiPayloadPkg/GraphicsOutputDxe/GraphicsOutput.c
index 39ad03fe32..894647c347 100644
--- a/UefiPayloadPkg/GraphicsOutputDxe/GraphicsOutput.c
+++ b/UefiPayloadPkg/GraphicsOutputDxe/GraphicsOutput.c
@@ -435,8 +435,11 @@ GraphicsOutputDriverBindingStart (
             }
 
             if (DeviceInfo->BarIndex == MAX_UINT8) {
-              if (Resources->AddrRangeMin == GraphicsInfo->FrameBufferBase) {
-                FrameBufferBase = Resources->AddrRangeMin;
+              if (  (GraphicsInfo->FrameBufferBase >= Resources->AddrRangeMin)
+                 && (GraphicsInfo->FrameBufferBase - Resources->AddrRangeMin <=
+                     Resources->AddrLen - GraphicsInfo->FrameBufferSize))
+              {
+                FrameBufferBase = GraphicsInfo->FrameBufferBase;
                 break;
               }
             } else {