Applied. Thanks! Alex
On Sun, Aug 16, 2026 at 8:43 PM Gilles Risch <[email protected]> wrote: > > The Apple iMac11,1 (27-inch, Late 2009) uses a Mobility Radeon HD 4850 > (RV770/DCE3.1) with a 2560x1440 internal panel on an internal > DisplayPort path. Without this fix the display stays dark under KMS. > > This machine suffers from the same issue as iMac10,1 and iMac11,2: > Apple routes the internal display through Link B of the DIG encoder > instead of Link A. Add iMac11,1 to the existing DMI quirk and move > the Apple-specific encoder assignment into its own block, independent > of the DCE version check. > > Additionally, the 2560x1440 panel requires RADEON_PLL_USE_FRAC_FB_DIV > and ATOM_ENCODER_CMD_DP_VIDEO_ON, limited to iMac11,1 via dmi_match() > to avoid affecting other boards. > > Signed-off-by: Gilles Risch <[email protected]> > > Good morning, > > this is v6 of the patch, rebased on top of amd-staging-drm-next > (agd5f/linux). > > There are no functional or code changes since v5. > > Regarding Lukas Wunner's previous Reviewed-by (which was provided on v2), > I have kept him in CC so he can confirm if his review still stands given > the changes between v2 and v5. > > Could you have a look at this when you have a spare moment? > > Regards, > Gilles > > Changes in v6: > - Rebased on amd-staging-drm-next (no functional/code changes since v5) > --- > drivers/gpu/drm/radeon/atombios_crtc.c | 5 ++++- > drivers/gpu/drm/radeon/atombios_encoders.c | 23 ++++++++++++---------- > 2 files changed, 17 insertions(+), 11 deletions(-) > > diff --git a/drivers/gpu/drm/radeon/atombios_crtc.c > b/drivers/gpu/drm/radeon/atombios_crtc.c > index 2fc0334e0d6c..075eba2d47f3 100644 > --- a/drivers/gpu/drm/radeon/atombios_crtc.c > +++ b/drivers/gpu/drm/radeon/atombios_crtc.c > @@ -24,6 +24,8 @@ > * Alex Deucher > */ > > +#include <linux/dmi.h> > + > #include <drm/drm_fixed.h> > #include <drm/drm_fourcc.h> > #include <drm/drm_framebuffer.h> > @@ -594,7 +596,8 @@ static u32 atombios_adjust_pll(struct drm_crtc *crtc, > if (((rdev->family == CHIP_RS780) || (rdev->family == > CHIP_RS880)) > && !radeon_crtc->ss_enabled) > radeon_crtc->pll_flags |= RADEON_PLL_USE_FRAC_FB_DIV; > - if (ASIC_IS_DCE32(rdev) && mode->clock > 165000) > + if ((ASIC_IS_DCE32(rdev) || dmi_match(DMI_PRODUCT_NAME, > "iMac11,1")) > + && mode->clock > 165000) > radeon_crtc->pll_flags |= RADEON_PLL_USE_FRAC_FB_DIV; > } else { > radeon_crtc->pll_flags |= RADEON_PLL_LEGACY; > diff --git a/drivers/gpu/drm/radeon/atombios_encoders.c > b/drivers/gpu/drm/radeon/atombios_encoders.c > index 5cfd8fcfa5e8..8b3f8303a967 100644 > --- a/drivers/gpu/drm/radeon/atombios_encoders.c > +++ b/drivers/gpu/drm/radeon/atombios_encoders.c > @@ -1707,7 +1707,7 @@ radeon_atom_encoder_dpms_dig(struct drm_encoder > *encoder, int mode) > if (ENCODER_MODE_IS_DP(atombios_get_encoder_mode(encoder)) && > connector) { > /* DP_SET_POWER_D0 is set in radeon_dp_link_train */ > radeon_dp_link_train(encoder, connector); > - if (ASIC_IS_DCE4(rdev)) > + if (ASIC_IS_DCE4(rdev) || dmi_match(DMI_PRODUCT_NAME, > "iMac11,1")) > atombios_dig_encoder_setup(encoder, > ATOM_ENCODER_CMD_DP_VIDEO_ON, 0); > } > if (radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT)) { > @@ -2123,17 +2123,20 @@ int radeon_atom_pick_dig_encoder(struct drm_encoder > *encoder, int fe_idx) > } > > /* > - * On DCE32 any encoder can drive any block so usually just use crtc > id, > - * but Apple thinks different at least on iMac10,1 and iMac11,2, so > there use linkb, > - * otherwise the internal eDP panel will stay dark. > + * Apple routes the internal eDP panel through Link B of the DIG > encoder > + * instead of Link A on the iMac10,1, iMac11,1 and iMac11,2. > + * Use linkb to avoid a dark display. > */ > - if (ASIC_IS_DCE32(rdev)) { > - if (dmi_match(DMI_PRODUCT_NAME, "iMac10,1") || > - dmi_match(DMI_PRODUCT_NAME, "iMac11,2")) > - enc_idx = (dig->linkb) ? 1 : 0; > - else > - enc_idx = radeon_crtc->crtc_id; > + if (dmi_match(DMI_PRODUCT_NAME, "iMac10,1") || > + dmi_match(DMI_PRODUCT_NAME, "iMac11,1") || > + dmi_match(DMI_PRODUCT_NAME, "iMac11,2")) { > + enc_idx = (dig->linkb) ? 1 : 0; > + goto assigned; > + } > > + /* on DCE32 and encoder can driver any block so just crtc id */ > + if (ASIC_IS_DCE32(rdev)) { > + enc_idx = radeon_crtc->crtc_id; > goto assigned; > } > > > base-commit: 21c50d41af7c46e138b542dba2dcf6d2a978ae99 > -- > 2.47.3 >
