From patchwork Sat Feb 2 00:41:14 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ben Widawsky X-Patchwork-Id: 2083441 Return-Path: X-Original-To: patchwork-dri-devel@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by patchwork2.kernel.org (Postfix) with ESMTP id 85767E00C6 for ; Sat, 2 Feb 2013 00:40:34 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 86C88E5CF3 for ; Fri, 1 Feb 2013 16:40:34 -0800 (PST) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from shiva.chad-versace.us (209-20-75-48.static.cloud-ips.com [209.20.75.48]) by gabe.freedesktop.org (Postfix) with ESMTP id 5F843E5CF3; Fri, 1 Feb 2013 16:39:56 -0800 (PST) Received: by shiva.chad-versace.us (Postfix, from userid 1005) id 3BDF388122; Sat, 2 Feb 2013 00:42:53 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on shiva.chad-versace.us X-Spam-Level: X-Spam-Status: No, score=-2.9 required=5.0 tests=ALL_TRUSTED,BAYES_00 autolearn=unavailable version=3.3.2 Received: from lundgren.kumite (c-24-21-100-90.hsd1.or.comcast.net [24.21.100.90]) by shiva.chad-versace.us (Postfix) with ESMTPSA id 07AAF8811D; Sat, 2 Feb 2013 00:42:41 +0000 (UTC) From: Ben Widawsky To: intel-gfx@lists.freedesktop.org Subject: [PATCH] drm/i915: Fix RC6VIDS encode/devoce Date: Fri, 1 Feb 2013 16:41:14 -0800 Message-Id: <1359765674-4903-1-git-send-email-ben@bwidawsk.net> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <20130201140750.GA25600@elgon.mountain> References: <20130201140750.GA25600@elgon.mountain> Cc: Ben Widawsky , stable@kernel.org, dri-devel@lists.freedesktop.org X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: dri-devel-bounces+patchwork-dri-devel=patchwork.kernel.org@lists.freedesktop.org Errors-To: dri-devel-bounces+patchwork-dri-devel=patchwork.kernel.org@lists.freedesktop.org The RC6 VIDS has a linear ramp starting at 250mv, which means any values below 250 are invalid. The old buggy macros tried to adjust for this to be more flexible, but there is no need. As Dan pointed out the ENCODE only ever has one value. The only invalid value for decode is an input of 0 which means something is really wonky, and the cases where DECODE are used either don't matter (debug values), or would be implicitly correct (the check for less than 450). This patch makes simpler, easier to read macros which are actually correct. Maybe this patch can actually fix some bugs now. Thanks to Dan for catching this. /me hides Cc: stable@kernel.org Reported-by: Dan Carpenter Signed-off-by: Ben Widawsky --- drivers/gpu/drm/i915/i915_reg.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index 59afb7e..2a754e2 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -4280,8 +4280,8 @@ #define GEN6_PCODE_READ_MIN_FREQ_TABLE 0x9 #define GEN6_PCODE_WRITE_RC6VIDS 0x4 #define GEN6_PCODE_READ_RC6VIDS 0x5 -#define GEN6_ENCODE_RC6_VID(mv) (((mv) / 5) - 245) < 0 ?: 0 -#define GEN6_DECODE_RC6_VID(vids) (((vids) * 5) > 0 ? ((vids) * 5) + 245 : 0) +#define GEN6_ENCODE_RC6_VID(mv) (((mv) - 245) / 5) +#define GEN6_DECODE_RC6_VID(vids) (((vids) * 5) + 245) #define GEN6_PCODE_DATA 0x138128 #define GEN6_PCODE_FREQ_IA_RATIO_SHIFT 8