From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 79598C8303C for ; Wed, 2 Jul 2025 21:29:43 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 33D6710E0B1; Wed, 2 Jul 2025 21:29:43 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="PjhXcPNu"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.16]) by gabe.freedesktop.org (Postfix) with ESMTPS id 35C7510E0B1; Wed, 2 Jul 2025 21:29:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1751491783; x=1783027783; h=date:from:to:cc:subject:message-id:references: mime-version:content-transfer-encoding:in-reply-to; bh=qGZLQ4lwHYpahuqhKTKlGW/UjrVgli2lynXGh7kgM1M=; b=PjhXcPNusyx2l3eHvjQn6+Mb739j16SI6sKac8HusnQ9vJTiRTM4BGMJ VuihctUEPdecl2PyLgqa+ifqg9S/Mmu/vhHm3LncNjlxBv+oFLOV+V69l sJgrH+sWZ3y+PxfdlGAGopIiVrBFrdoozYMnyEDQAyA+dKvyAQlGB7w3/ uucfBz/KiBt9zKcCXefyMpok1LP/4TobouRPnchvWg77cVOYQ+f7gOSxf 3k+CFTr6wsirjMTK9kL3CEEhxuC9pBHX8V0QL7Dmyl2nDR48A1QGA9MfC dxoxM8JT4Tsl9N2ttyEOiMJxMVeHHhIWwtnulXox+0vlxNNCkOvTbA42u w==; X-CSE-ConnectionGUID: kG2ERVlRRASqBG9ddmCyQQ== X-CSE-MsgGUID: 916f/xLrSAua7XN3mGRpUw== X-IronPort-AV: E=McAfee;i="6800,10657,11482"; a="53916359" X-IronPort-AV: E=Sophos;i="6.16,282,1744095600"; d="scan'208";a="53916359" Received: from orviesa005.jf.intel.com ([10.64.159.145]) by orvoesa108.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Jul 2025 14:29:42 -0700 X-CSE-ConnectionGUID: VUP3VsBmRHmwQsoUo+Lqxw== X-CSE-MsgGUID: d48LDm47RwuJLvumahN6Rw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.16,282,1744095600"; d="scan'208";a="159875632" Received: from kniemiec-mobl1.ger.corp.intel.com (HELO stinkbox) ([10.245.244.30]) by orviesa005.jf.intel.com with SMTP; 02 Jul 2025 14:29:39 -0700 Received: by stinkbox (sSMTP sendmail emulation); Thu, 03 Jul 2025 00:29:37 +0300 Date: Thu, 3 Jul 2025 00:29:37 +0300 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= To: Lucas De Marchi Cc: Ankit Nautiyal , intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org, jani.nikula@linux.intel.com, gustavo.sousa@intel.com, Jani Nikula Subject: Re: [PATCH 1/2] drm/i915/display_wa: Add helpers to check wa Message-ID: References: <20250702084620.3837426-1-ankit.k.nautiyal@intel.com> <20250702084620.3837426-2-ankit.k.nautiyal@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Patchwork-Hint: comment X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" On Wed, Jul 02, 2025 at 03:25:21PM -0500, Lucas De Marchi wrote: > On Wed, Jul 02, 2025 at 10:40:34PM +0300, Ville Syrjälä wrote: > >On Wed, Jul 02, 2025 at 02:16:18PM +0530, Ankit Nautiyal wrote: > >> Introduce a generic helper to check display workarounds using an enum. > >> > >> Convert Wa_16023588340 to use the new interface, simplifying WA checks > >> and making future additions easier. > >> > >> v2: Use drm_WARN instead of MISSING_CASE and simplify intel_display_wa > >> macro. (Jani) > >> > >> Suggested-by: Jani Nikula > >> Signed-off-by: Ankit Nautiyal > >> --- > >> drivers/gpu/drm/i915/display/intel_display_wa.c | 15 +++++++++++++++ > >> drivers/gpu/drm/i915/display/intel_display_wa.h | 9 +++++++++ > >> drivers/gpu/drm/i915/display/intel_fbc.c | 2 +- > >> 3 files changed, 25 insertions(+), 1 deletion(-) > >> > >> diff --git a/drivers/gpu/drm/i915/display/intel_display_wa.c b/drivers/gpu/drm/i915/display/intel_display_wa.c > >> index f57280e9d041..f5e8d58d9a68 100644 > >> --- a/drivers/gpu/drm/i915/display/intel_display_wa.c > >> +++ b/drivers/gpu/drm/i915/display/intel_display_wa.c > >> @@ -3,6 +3,8 @@ > >> * Copyright © 2023 Intel Corporation > >> */ > >> > >> +#include "drm/drm_print.h" > >> + > >> #include "i915_reg.h" > >> #include "intel_de.h" > >> #include "intel_display_core.h" > >> @@ -39,3 +41,16 @@ void intel_display_wa_apply(struct intel_display *display) > >> else if (DISPLAY_VER(display) == 11) > >> gen11_display_wa_apply(display); > >> } > >> + > >> +bool __intel_display_wa(struct intel_display *display, enum intel_display_wa wa) > >> +{ > >> + switch (wa) { > >> + case INTEL_DISPLAY_WA_16023588340: > >> + return intel_display_needs_wa_16023588340(display); > >> + default: > >> + drm_WARN(display->drm, 1, "Missing Wa number: %d\n", wa); > >> + break; > >> + } > >> + > >> + return false; > >> +} > >> diff --git a/drivers/gpu/drm/i915/display/intel_display_wa.h b/drivers/gpu/drm/i915/display/intel_display_wa.h > >> index babd9d16603d..146ee70d66f7 100644 > >> --- a/drivers/gpu/drm/i915/display/intel_display_wa.h > >> +++ b/drivers/gpu/drm/i915/display/intel_display_wa.h > >> @@ -21,4 +21,13 @@ static inline bool intel_display_needs_wa_16023588340(struct intel_display *disp > >> bool intel_display_needs_wa_16023588340(struct intel_display *display); > >> #endif > >> > >> +enum intel_display_wa { > >> + INTEL_DISPLAY_WA_16023588340, > > > >How is anyone supposed to keep track of these random numbers > >and what they mean? > > they mean there's a h/w workaround that requires that and this is the id > if you need to find more details about it or what platforms/IPs use > that. I don't want to go look up all the details in the common case. I just want to read the code and see that it generally makes sense without having to trawl through the spec/hsd for an hour every time. > > > > >The only time I want to see these numbers is if I really have to > >open the spec/hsd for it to double check some details. Othwerwise > >it just seems like pointless noise that makes it harder to follow > >the code/figure out what the heck is going on. > > what is the alternative? The current status quo checking by platform > and/or IP version, dissociated from the WA numbers? I find it easiest if everything is in one place. I think every w/a generally should have these: - which hardware is affected - what other runtime conditions are required to hit the issue - what is being done to avoid the issue - a short human readable explanation of the issue - the w/a number for looking up futher details Splitting it all up into random bits and pieces just means more jumping around all the time, which I find annoying at best. -- Ville Syrjälä Intel