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 34076C5DF94 for ; Fri, 21 Aug 2026 22:23:56 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B39E910F3E0; Fri, 21 Aug 2026 22:23:55 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="FYW6NqWC"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.13]) by gabe.freedesktop.org (Postfix) with ESMTPS id ED88210E283 for ; Fri, 21 Aug 2026 22:23:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1787351025; x=1818887025; h=from:to:subject:date:message-id:mime-version: content-transfer-encoding; bh=ve5Y0tRY5b4HyQzrTQVKNpFnSEXA/qSIiJymXGVe9Zs=; b=FYW6NqWCoE0I8kO74JzOMa98RCfn2fYpzkhIUlhvgMsZwYLd8sB3bXGD wy1Inf01IxWIM49jBDsmgm9wjecqfXjEgL3A2XPORjHFHXjDK+IB4dOBN fNBOUMJk42XvRRc+uOp2En5j4AjfNh+/LFiRsgH/cu11Yg/xzkosqPdc6 gmABKz6z7s6sj9iWZqC2lIs3O0BhV6Z196/NIDsTtv9Rkf0J3NKt5hnJH I7giDCFNPxbj2bhBkIt//n3o8f0iQeT/iZ/BFyXMp0UUZsz51M9G+xLF6 iYPUSdmQtkbPYMrGpbGFwkh5QcvZm4lJmofI2VoomPDS3uxXLx4YyzlRZ A==; X-CSE-ConnectionGUID: j98wi8QQRceoxV9R75iNRQ== X-CSE-MsgGUID: SCrljbxdTaO7WMFNEJHuzA== X-IronPort-AV: E=McAfee;i="6800,10657,11882"; a="90420767" X-IronPort-AV: E=Sophos;i="6.25,235,1779174000"; d="scan'208";a="90420767" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by fmvoesa107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Aug 2026 15:23:45 -0700 X-CSE-ConnectionGUID: q8OiBHzARt+NMRBz5edW+g== X-CSE-MsgGUID: wN7IDo8zS3OuZ3/Y2YuAqw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,235,1779174000"; d="scan'208";a="263198167" Received: from orsosgc001.jf.intel.com ([10.88.27.185]) by fmviesa007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Aug 2026 15:23:44 -0700 From: Umesh Nerlige Ramappa To: intel-xe@lists.freedesktop.org, Ashutosh Dixit Subject: [PATCH 0/3] Modify the SW tail logic in OA Date: Fri, 21 Aug 2026 15:23:39 -0700 Message-ID: <20260821222338.1053887-5-umesh.nerlige.ramappa@intel.com> X-Mailer: git-send-email 2.51.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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" OA unit updates the HW TAIL register to indicate that a new report is available, although it does not guarantee that the report is visible in memory. Also the currently running workload contributes to some latency in seeing this report in memory. In the past we would set some fields in the OA report and check if the fields are populated to non-zero values by the HW, but this is no longer sufficient since some parts of the report may land out of order under heavy workloads. Drop this WA and add a new logic that just waits for a fixed number of HW TAIL report increments before returning data to the user. User will always see the reports lagging by this fixed number, however we do not have realtime use cases for OAG since OAG reports are mainly post processed. v2: Rebase v3: Add Sashiko's review comments v4: Rebase, checkpatch fixes v5: Add Ashutosh's review comments v6: Add Sashiko's review comment Signed-off-by: Umesh Nerlige Ramappa Umesh Nerlige Ramappa (3): drm/xe/xe_oa: Clear status only if relevant bits are set drm/xe/xe_oa: Avoid checking and setting fields in the OA report drm/xe/xe_oa: Add a lag to the reports that is exported to user drivers/gpu/drm/xe/xe_oa.c | 108 ++++++++----------------------------- 1 file changed, 21 insertions(+), 87 deletions(-) -- 2.51.0