From 564d8a2cf3abf16575af48bdc3e86e92ee8a617d Mon Sep 17 00:00:00 2001 From: Mario Kleiner Date: Fri, 7 Jul 2017 04:57:04 +0200 Subject: [PATCH] drm/radeon: Fix eDP for single-display iMac10,1 (v2) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The late 2009, 27 inch Apple iMac10,1 has an internal eDP display and an external Mini- Displayport output, driven by a DCE-3.2, RV730 Radeon Mobility HD-4670. The machine worked fine in a dual-display setup with eDP panel + externally connected HDMI or DVI-D digital display sink, connected via MiniDP to DVI or HDMI adapter. However, booting the machine single-display with only eDP panel results in a completely black display - even backlight powering off, as soon as the radeon modesetting driver loads. This patch fixes the single dispay eDP case by assigning encoders based on dig->linkb, similar to DCE-4+. While this should not be generally necessary (Alex: "...atom on normal boards should be able to handle any mapping."), Apple seems to use some special routing here. One remaining problem not solved by this patch is that an external Minidisplayport->DP sink does still not work on iMac10,1, whereas external DVI and HDMI sinks continue to work. The problem affects at least all tested kernels since Linux 3.13 - didn't test earlier kernels, so backporting to stable probably makes sense. v2: With the original patch from 2016, Alex was worried it will break other DCE3.2 systems. Use dmi_match() to apply this special encoder assignment only for the Apple iMac 10,1 from late 2009. Signed-off-by: Mario Kleiner Cc: Alex Deucher Cc: Michel Dänzer Cc: Signed-off-by: Alex Deucher --- drivers/gpu/drm/radeon/atombios_encoders.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/radeon/atombios_encoders.c b/drivers/gpu/drm/radeon/atombios_encoders.c index fa4f8f008e4d..e67ed383e11b 100644 --- a/drivers/gpu/drm/radeon/atombios_encoders.c +++ b/drivers/gpu/drm/radeon/atombios_encoders.c @@ -31,6 +31,7 @@ #include "radeon_asic.h" #include "atom.h" #include +#include extern int atom_debug; @@ -2184,9 +2185,17 @@ int radeon_atom_pick_dig_encoder(struct drm_encoder *encoder, int fe_idx) goto assigned; } - /* on DCE32 and encoder can driver any block so just crtc id */ + /* + * On DCE32 any encoder can drive any block so usually just use crtc id, + * but Apple thinks different at least on iMac10,1, so there use linkb, + * otherwise the internal eDP panel will stay dark. + */ if (ASIC_IS_DCE32(rdev)) { - enc_idx = radeon_crtc->crtc_id; + if (dmi_match(DMI_PRODUCT_NAME, "iMac10,1")) + enc_idx = (dig->linkb) ? 1 : 0; + else + enc_idx = radeon_crtc->crtc_id; + goto assigned; }