diff options
Diffstat (limited to 'drivers/gpu/drm/i915/intel_display.c')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_display.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 1ce4ad4626e4..bcbd742149c6 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -1516,6 +1516,25 @@ static void intel_reset_dpio(struct drm_device *dev) } else { /* + * If DPIO has already been reset, e.g. by BIOS, just skip all + * this. + */ + if (I915_READ(DPIO_CTL) & DPIO_CMNRST) + return; + + /* + * From VLV2A0_DP_eDP_HDMI_DPIO_driver_vbios_notes_11.docx: + * Need to assert and de-assert PHY SB reset by gating the + * common lane power, then un-gating it. + * Simply ungating isn't enough to reset the PHY enough to get + * ports and lanes running. + */ + __vlv_set_power_well(dev_priv, PUNIT_POWER_WELL_DPIO_CMN_BC, + false); + __vlv_set_power_well(dev_priv, PUNIT_POWER_WELL_DPIO_CMN_BC, + true); + + /* * From VLV2A0_DP_eDP_DPIO_driver_vbios_notes_10.docx - * 6. De-assert cmn_reset/side_reset. Same as VLV X0. * a. GUnit 0x2110 bit[0] set to 1 (def 0) |