From: Jerome Glisse jglisse@redhat.com
This fix black screen on resume issue that some people are experiencing. There is a bug in the atombios code regarding pll/crtc mapping. The atombios code reverse the logic for the pll and crtc mapping.
v2: DCE3 or DCE2 only have 2 crtc
Signed-off-by: Jerome Glisse jglisse@redhat.com --- drivers/gpu/drm/radeon/atombios_crtc.c | 48 ++++++++++------------------------ 1 file changed, 14 insertions(+), 34 deletions(-)
diff --git a/drivers/gpu/drm/radeon/atombios_crtc.c b/drivers/gpu/drm/radeon/atombios_crtc.c index 3bce029..24d932f 100644 --- a/drivers/gpu/drm/radeon/atombios_crtc.c +++ b/drivers/gpu/drm/radeon/atombios_crtc.c @@ -1696,42 +1696,22 @@ static int radeon_atom_pick_pll(struct drm_crtc *crtc) return ATOM_PPLL2; DRM_ERROR("unable to allocate a PPLL\n"); return ATOM_PPLL_INVALID; - } else if (ASIC_IS_AVIVO(rdev)) { - /* in DP mode, the DP ref clock can come from either PPLL - * depending on the asic: - * DCE3: PPLL1 or PPLL2 - */ - if (ENCODER_MODE_IS_DP(atombios_get_encoder_mode(radeon_crtc->encoder))) { - /* use the same PPLL for all DP monitors */ - pll = radeon_get_shared_dp_ppll(crtc); - if (pll != ATOM_PPLL_INVALID) - return pll; - } else { - /* use the same PPLL for all monitors with the same clock */ - pll = radeon_get_shared_nondp_ppll(crtc); - if (pll != ATOM_PPLL_INVALID) - return pll; - } - /* all other cases */ - pll_in_use = radeon_get_pll_use_mask(crtc); - /* the order shouldn't matter here, but we probably - * need this until we have atomic modeset - */ - if (rdev->flags & RADEON_IS_IGP) { - if (!(pll_in_use & (1 << ATOM_PPLL1))) - return ATOM_PPLL1; - if (!(pll_in_use & (1 << ATOM_PPLL2))) - return ATOM_PPLL2; - } else { - if (!(pll_in_use & (1 << ATOM_PPLL2))) - return ATOM_PPLL2; - if (!(pll_in_use & (1 << ATOM_PPLL1))) - return ATOM_PPLL1; - } - DRM_ERROR("unable to allocate a PPLL\n"); - return ATOM_PPLL_INVALID; } else { /* on pre-R5xx asics, the crtc to pll mapping is hardcoded */ + /* some atombios (observed in some DCE2/DCE3) code have a bug, + * the matching btw pll and crtc is done through + * PCLK_CRTC[1|2]_CNTL (0x480/0x484) but atombios code use the + * pll (1 or 2) to select which register to write. ie if using + * pll1 it will use PCLK_CRTC1_CNTL (0x480) and if using pll2 + * it will use PCLK_CRTC2_CNTL (0x484), it then use crtc id to + * choose which value to write. Which is reverse order from + * register logic. So only case that works is when pllid is + * same as crtcid or when both pll and crtc are enabled and + * both use same clock. + * + * So just return crtc id as if crtc and pll were hard linked + * together even if they aren't + */ return radeon_crtc->crtc_id; } }