From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Wilson Subject: Re: [PATCH] drm/i915: clarify IS_GEN vs IS_ usage Date: Tue, 10 May 2011 22:24:43 +0100 Message-ID: <382e69$ctpctm@azsmga001.ch.intel.com> References: <1304633805-7505-1-git-send-email-jbarnes@virtuousgeek.org> <0d30dc$m4ic2q@orsmga001.jf.intel.com> <20110509114213.34816211@jbarnes-desktop> <874o52xul9.fsf@pollan.anholt.net> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga14.intel.com (mga14.intel.com [143.182.124.37]) by gabe.freedesktop.org (Postfix) with ESMTP id 6BA989E7F7 for ; Tue, 10 May 2011 14:24:47 -0700 (PDT) In-Reply-To: <874o52xul9.fsf@pollan.anholt.net> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: Eric Anholt , Jesse Barnes Cc: intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org On Tue, 10 May 2011 11:45:54 -0700, Eric Anholt wrote: > On Mon, 9 May 2011 11:42:13 -0700, Jesse Barnes wrote: > This feels like a lot of churn to me, for the pre-gen4 chipsets at > least. gen2 is always is_830_display (which is overly specific), and > gen3 is always is_i915_display. The argument is that we want to be consistent in how we test for capabilities so that adding new feature tests or new chipsets is easier and has no side-effects with existing capabilities. How the macros map on to the actual devices is another matter - a compromise between simplicity and runtime efficiency. If it doesn't reduce our long term maintenance burden, then there is no point making the distinction. I think more fine-grained checks will help in the future, (and consistency across all generations prevents silly bugs). I'm still skeptical that the segregation of capabilities between chipset/display/render is as clear cut as Jesse portrays. ;-) -Chris -- Chris Wilson, Intel Open Source Technology Centre