cannonlake mainboards: Set PMC as hidden in devicetree

FSP-S hides the PMC from the PCI bus when it runs, but there are still
initialization steps coreboot programs for the PMC. Therefore, change
all of the cannonlake mainboards to set the PMC as hidden in the
devicetree, which means the device will be skipped during enumeration,
but device callbacks are still issued as if the device were enabled.

TEST=Ran full patch train on google/dratini, disassembled SSDT and the
PEPD device matches what is in pep.asl. Also verified via dmesg that the
INT33A1 device is still initialized by the kernel.

Signed-off-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Change-Id: Ib4a20ce9075ce7653388a5d3e281fe774bf89355
Reviewed-on: https://review.coreboot.org/c/coreboot/+/56008
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by:  Felix Singer <felixsinger@posteo.net>
Reviewed-by: Furquan Shaikh <furquan@google.com>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Nico Huber <nico.h@gmx.de>
Reviewed-by: Michael Niewöhner <foss@mniewoehner.de>

1 files changed, 1 insertions, 1 deletions

diff --git a/src/mainboard/system76/gaze15/devicetree.cb b/src/mainboard/system76/gaze15/devicetree.cb
index 1aec60f6d0..f8e879db86 100644
--- a/src/mainboard/system76/gaze15/devicetree.cb
+++ b/src/mainboard/system76/gaze15/devicetree.cb
@@ -201,7 +201,7 @@ chip soc/intel/cannonlake
 			end
 		end
 		device pci 1f.1 off end # P2SB
-		device pci 1f.2 off end # Power Management Controller
+		device pci 1f.2 hidden end # Power Management Controller
 		device pci 1f.3 on      # Intel HDA
 			register "PchHdaAudioLinkHda" = "1"
 			register "PchHdaAudioLinkDmic0" = "1"