From patchwork Wed Dec 6 22:47:38 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dhinakaran Pandiyan X-Patchwork-Id: 10097311 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 28E376056E for ; Wed, 6 Dec 2017 22:48:21 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1BA6329B30 for ; Wed, 6 Dec 2017 22:48:21 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 10D4829BAA; Wed, 6 Dec 2017 22:48:21 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id CEC5729B30 for ; Wed, 6 Dec 2017 22:48:20 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 364726E730; Wed, 6 Dec 2017 22:48:15 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by gabe.freedesktop.org (Postfix) with ESMTPS id AB75A89F75; Wed, 6 Dec 2017 22:48:13 +0000 (UTC) Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 06 Dec 2017 14:48:13 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.45,369,1508828400"; d="scan'208";a="11207238" Received: from dk-thinkpad-x260.jf.intel.com (HELO localhost.localdomain) ([10.54.75.38]) by fmsmga001.fm.intel.com with ESMTP; 06 Dec 2017 14:48:12 -0800 From: Dhinakaran Pandiyan To: intel-gfx@lists.freedesktop.org Date: Wed, 6 Dec 2017 14:47:38 -0800 Message-Id: <20171206224741.8600-2-dhinakaran.pandiyan@intel.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20171206224741.8600-1-dhinakaran.pandiyan@intel.com> References: <20171206224741.8600-1-dhinakaran.pandiyan@intel.com> Cc: Daniel Vetter , Dhinakaran Pandiyan , dri-devel@lists.freedesktop.org, Rodrigo Vivi Subject: [Intel-gfx] [PATCH 2/5] drm/vblank: Restoring vblank counts after device runtime PM events. X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP The HW frame counter can get reset when devices enters low power states and this messes up any following vblank count updates. So, compute the missed vblank interrupts for that low power state duration using time stamps. This is similar to _crtc_vblank_on() except that it doesn't enable vblank interrupts because this function is expected to be called from the driver _enable_vblank() vfunc. Signed-off-by: Dhinakaran Pandiyan --- drivers/gpu/drm/drm_vblank.c | 30 ++++++++++++++++++++++++++++++ include/drm/drm_vblank.h | 1 + 2 files changed, 31 insertions(+) diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c index 7eee82c06ed8..69d537cea149 100644 --- a/drivers/gpu/drm/drm_vblank.c +++ b/drivers/gpu/drm/drm_vblank.c @@ -1230,6 +1230,36 @@ void drm_crtc_vblank_on(struct drm_crtc *crtc) } EXPORT_SYMBOL(drm_crtc_vblank_on); +void drm_crtc_vblank_restore(struct drm_device *dev, unsigned int pipe) +{ + ktime_t t_vblank; + struct drm_vblank_crtc *vblank; + int framedur_ns; + u64 diff_ns; + u32 cur_vblank, diff = 1; + int count = DRM_TIMESTAMP_MAXRETRIES; + + if (WARN_ON(pipe >= dev->num_crtcs)) + return; + + vblank = &dev->vblank[pipe]; + framedur_ns = vblank->framedur_ns; + + do { + cur_vblank = __get_vblank_counter(dev, pipe); + drm_get_last_vbltimestamp(dev, pipe, &t_vblank, false); + } while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0); + + diff_ns = ktime_to_ns(ktime_sub(t_vblank, vblank->time)); + if (framedur_ns) + diff = DIV_ROUND_CLOSEST_ULL(diff_ns, framedur_ns); + + DRM_DEBUG_VBL("computing missed vblanks %lld/%d=%d after HW counter reset hw_diff=%d\n", + diff_ns, framedur_ns, diff, cur_vblank - vblank->last); + store_vblank(dev, pipe, diff, t_vblank, cur_vblank); +} +EXPORT_SYMBOL(drm_crtc_vblank_restore); + static void drm_legacy_vblank_pre_modeset(struct drm_device *dev, unsigned int pipe) { diff --git a/include/drm/drm_vblank.h b/include/drm/drm_vblank.h index 848b463a0af5..aafcbef91bd7 100644 --- a/include/drm/drm_vblank.h +++ b/include/drm/drm_vblank.h @@ -180,6 +180,7 @@ void drm_crtc_vblank_off(struct drm_crtc *crtc); void drm_crtc_vblank_reset(struct drm_crtc *crtc); void drm_crtc_vblank_on(struct drm_crtc *crtc); u32 drm_crtc_accurate_vblank_count(struct drm_crtc *crtc); +void drm_crtc_vblank_restore(struct drm_device *dev, unsigned int pipe); bool drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, unsigned int pipe, int *max_error,