diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index a89d0fd1c2e1..cbdebb022273 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -9555,7 +9555,16 @@ static void i9xx_update_cursor(struct intel_plane *plane, * On some platforms writing CURCNTR first will also * cause CURPOS to be armed by the CURBASE write. * Without the CURCNTR write the CURPOS write would - * arm itself. + * arm itself. Thus we always start the full update + * with a CURCNTR write. + * + * On other platforms CURPOS always requires the + * CURBASE write to arm the update. Additonally + * a write to any of the cursor register will cancel + * an already armed cursor update. Thus leaving out + * the CURBASE write after CURPOS could lead to a + * cursor that doesn't appear to move, or even change + * shape. Thus we always write CURBASE. * * CURCNTR and CUR_FBC_CTL are always * armed by the CURBASE write only. @@ -9574,6 +9583,7 @@ static void i9xx_update_cursor(struct intel_plane *plane, plane->cursor.cntl = cntl; } else { I915_WRITE_FW(CURPOS(pipe), pos); + I915_WRITE_FW(CURBASE(pipe), base); } POSTING_READ_FW(CURBASE(pipe));