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 737C3C5AC7C for ; Thu, 6 Aug 2026 22:47:17 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 232F310E217; Thu, 6 Aug 2026 22:47:17 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="BLEz1Rbg"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.17]) by gabe.freedesktop.org (Postfix) with ESMTPS id 70D8F10E217 for ; Thu, 6 Aug 2026 22:47:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1786056436; x=1817592436; h=from:to:subject:date:message-id:mime-version: content-transfer-encoding; bh=wVEVmiYqHO16R4osZ4BFwuWF9CUnp3kmUkXgCwFrtR4=; b=BLEz1RbgG/R2kYipTpDab2I6+aG2m+Ap75jNaTs2mEg4WjrSvvLBnp18 k1el0mdCL9/qtfyaL3J6I92we4vRBjuXV+jyq1NA+wIlNPSijzBwNCSM+ BdKBGjQfNN4+mBnaUW0lwon6Qo73PjOEH0jGinnwx3e1EsOX9shkt2HOk 4qj/Kp4UIKPMy49BsGvKk9iD64B40otmQmjV+fqzAym8U6uwq/vA8ayr2 NDXU2y3OyfdVK0YjQ/AntBgF4mRytvATtZK4KAhOqsaKLdvBW3ngZ9SAa jwNB8hcp0sfargbdcTQZUReOQAHpBdZLYpVjMPJEvTd6T049kd4D0UTkF A==; X-CSE-ConnectionGUID: IaLbGDP5Tl+MXq+RUNo5zQ== X-CSE-MsgGUID: edJFMx7+RKu7H0elLjZPhA== X-IronPort-AV: E=McAfee;i="6800,10657,11867"; a="86675963" X-IronPort-AV: E=Sophos;i="6.25,209,1779174000"; d="scan'208";a="86675963" Received: from fmviesa010.fm.intel.com ([10.60.135.150]) by orvoesa109.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Aug 2026 15:47:15 -0700 X-CSE-ConnectionGUID: 7R4mmmx6RgyrxNBBqSLjZg== X-CSE-MsgGUID: B/dCDYRXT9GZ36i2salGOg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,209,1779174000"; d="scan'208";a="258373136" Received: from orsosgc001.jf.intel.com ([10.88.27.185]) by fmviesa010-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Aug 2026 15:47:15 -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: Thu, 6 Aug 2026 15:47:03 -0700 Message-ID: <20260806224702.3563031-5-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 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 | 95 ++++++-------------------------------- 1 file changed, 13 insertions(+), 82 deletions(-) -- 2.51.0