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lbmk/config/coreboot/default/patches/0013-nb-haswell-Fully-disable-iGPU-when-dGPU-is-used.patch
T
Leah Rowe ad2d082bc2 Revert "cb/default: use rev 62c8197dd25376cb7b18d272af167cb176d28bcf"
This reverts commit fedeb6ecd8.

this, along with several other updates, have been reverted.
dell 3050 micro had boot issues, on the update. i therefore
revert the recent revision update, pending further investigation.
2026-05-19 11:54:05 +01:00

52 lines
1.6 KiB
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From df64f2825157226b98e002e746114e25b0047438 Mon Sep 17 00:00:00 2001
From: Leah Rowe <info@minifree.org>
Date: Sat, 6 Apr 2024 01:22:47 +0100
Subject: [PATCH 13/48] nb/haswell: Fully disable iGPU when dGPU is used
My earlier patch disabled decode *and* disabled the iGPU itself, but
a subsequent revision disabled only VGA decode. Upon revisiting, I
found that, actually, yes, you also need to disable the iGPU entirely.
Tested on Dell 9020 SFF using broadwell MRC, with both iGPU and dGPU.
With this patch, the iGPU is completely disabled when you install a
graphics card, but the iGPU is available to use when no graphics card
is present.
For more context, see:
Author: Leah Rowe <info@minifree.org>
Date: Fri Feb 23 13:33:31 2024 +0000
nb/haswell: Disable iGPU when dGPU is used
And look at the Gerrit comments:
https://review.coreboot.org/c/coreboot/+/80717/
So, my original submission on change 80717 was actually correct.
This patch fixes the issue. I tested on iGPU and dGPU, with both
broadwell and haswell mrc.bin.
Signed-off-by: Leah Rowe <info@minifree.org>
---
src/northbridge/intel/haswell/gma.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/src/northbridge/intel/haswell/gma.c b/src/northbridge/intel/haswell/gma.c
index f7fad3183d..1b188e92e1 100644
--- a/src/northbridge/intel/haswell/gma.c
+++ b/src/northbridge/intel/haswell/gma.c
@@ -466,6 +466,9 @@ static void gma_func0_disable(struct device *dev)
{
/* Disable VGA decode */
pci_or_config16(pcidev_on_root(0, 0), GGC, 1 << 1);
+
+ /* Required or else the graphics card doesn't work */
+ dev->enabled = 0;
}
static struct device_operations gma_func0_ops = {
--
2.47.3