From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934256Ab0HXXfU (ORCPT ); Tue, 24 Aug 2010 19:35:20 -0400 Received: from kroah.org ([198.145.64.141]:40405 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932900Ab0HXW6q (ORCPT ); Tue, 24 Aug 2010 18:58:46 -0400 X-Mailbox-Line: From gregkh@clark.site Tue Aug 24 15:42:15 2010 Message-Id: <20100824224215.168189276@clark.site> User-Agent: quilt/0.48-11.2 Date: Tue, 24 Aug 2010 15:41:58 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Daniel Vetter , Eric Anholt Subject: [36/91] drm/i915: i8xx also doesnt like multiple oustanding pageflips In-Reply-To: <20100824224617.GA5440@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.34-stable review patch. If anyone has any objections, please let us know. ------------------ From: Daniel Vetter commit 6146b3d61925116e3fecce36c2fd873665bd6614 upstream. My i855GM suffers from a 80k/s interrupt storm without this. So add 2nd gen to the list of things that don't like more than one outstanding pageflip request. Furthermore I've changed the busy loop into a ringbuffer wait. Busy-loops that don't check whether the chip died are simply evil. And performance should actually improve, because there's usually a decent amount of rendering queued on the gpu, hopefully rendering that MI_WAIT into a noop by the time it's executed. The current code holds dev->struct_mutex while executing this loop, hence stalling all other gem activity anyway. Signed-off-by: Daniel Vetter Reviewed-by: Jesse Barnes [anholt: resolved against conflict] Signed-off-by: Eric Anholt Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/i915/intel_display.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -4290,14 +4290,16 @@ static int intel_crtc_page_flip(struct d work->pending_flip_obj = obj; if (intel_crtc->plane) - flip_mask = I915_DISPLAY_PLANE_B_FLIP_PENDING_INTERRUPT; + flip_mask = MI_WAIT_FOR_PLANE_B_FLIP; else - flip_mask = I915_DISPLAY_PLANE_A_FLIP_PENDING_INTERRUPT; + flip_mask = MI_WAIT_FOR_PLANE_A_FLIP; - /* Wait for any previous flip to finish */ - if (IS_GEN3(dev)) - while (I915_READ(ISR) & flip_mask) - ; + if (IS_GEN3(dev) || IS_GEN2(dev)) { + BEGIN_LP_RING(2); + OUT_RING(MI_WAIT_FOR_EVENT | flip_mask); + OUT_RING(0); + ADVANCE_LP_RING(); + } /* Offset into the new buffer for cases of shared fbs between CRTCs */ offset = obj_priv->gtt_offset;