From patchwork Tue Nov 27 18:20:04 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= X-Patchwork-Id: 10701301 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8D3DD13BB for ; Tue, 27 Nov 2018 18:20:29 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8039C2C64B for ; Tue, 27 Nov 2018 18:20:29 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 73DE82C758; Tue, 27 Nov 2018 18:20:29 +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=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, 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 033E12C64B for ; Tue, 27 Nov 2018 18:20:23 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 01B236E129; Tue, 27 Nov 2018 18:20:12 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mga18.intel.com (mga18.intel.com [134.134.136.126]) by gabe.freedesktop.org (Postfix) with ESMTPS id BCBBC6E129; Tue, 27 Nov 2018 18:20:10 +0000 (UTC) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga106.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 27 Nov 2018 10:20:09 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,287,1539673200"; d="scan'208";a="93950287" Received: from stinkbox.fi.intel.com (HELO stinkbox) ([10.237.72.174]) by fmsmga008.fm.intel.com with SMTP; 27 Nov 2018 10:20:05 -0800 Received: by stinkbox (sSMTP sendmail emulation); Tue, 27 Nov 2018 20:20:04 +0200 From: Ville Syrjala To: intel-gfx@lists.freedesktop.org Subject: [PATCH v2 01/15] drm/vblank: Allow dynamic per-crtc max_vblank_count Date: Tue, 27 Nov 2018 20:20:04 +0200 Message-Id: <20181127182004.28885-1-ville.syrjala@linux.intel.com> X-Mailer: git-send-email 2.18.1 In-Reply-To: <20181112170000.27531-2-ville.syrjala@linux.intel.com> References: <20181112170000.27531-2-ville.syrjala@linux.intel.com> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: stable@vger.kernel.org, dri-devel@lists.freedesktop.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: Ville Syrjälä On i965gm we need to adjust max_vblank_count dynamically depending on whether the TV encoder is used or not. To that end add a per-crtc max_vblank_count that takes precedence over its device wide counterpart. The driver can now call drm_crtc_set_max_vblank_count() to configure the per-crtc value before calling drm_vblank_on(). Also looks like there was some discussion about exynos needing similar treatment. v2: Drop the extra max_vblank_count!=0 check for the WARN(last!=current), will take care of it in i915 code (Daniel) WARN_ON(!inmodeset) (Daniel) WARN_ON(dev->max_vblank_count) Pimp up the docs (Daniel) Cc: stable@vger.kernel.org Cc: Inki Dae Cc: Daniel Vetter Signed-off-by: Ville Syrjälä Reviewed-by: Daniel Vetter --- drivers/gpu/drm/drm_vblank.c | 45 +++++++++++++++++++++++++++++++++--- include/drm/drm_device.h | 8 ++++++- include/drm/drm_vblank.h | 22 ++++++++++++++++++ 3 files changed, 71 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c index 98e091175921..cde71ee95a8f 100644 --- a/drivers/gpu/drm/drm_vblank.c +++ b/drivers/gpu/drm/drm_vblank.c @@ -105,13 +105,20 @@ static void store_vblank(struct drm_device *dev, unsigned int pipe, write_sequnlock(&vblank->seqlock); } +static u32 drm_max_vblank_count(struct drm_device *dev, unsigned int pipe) +{ + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + + return vblank->max_vblank_count ?: dev->max_vblank_count; +} + /* * "No hw counter" fallback implementation of .get_vblank_counter() hook, * if there is no useable hardware frame counter available. */ static u32 drm_vblank_no_hw_counter(struct drm_device *dev, unsigned int pipe) { - WARN_ON_ONCE(dev->max_vblank_count != 0); + WARN_ON_ONCE(drm_max_vblank_count(dev, pipe) != 0); return 0; } @@ -198,6 +205,7 @@ static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe, ktime_t t_vblank; int count = DRM_TIMESTAMP_MAXRETRIES; int framedur_ns = vblank->framedur_ns; + u32 max_vblank_count = drm_max_vblank_count(dev, pipe); /* * Interrupts were disabled prior to this call, so deal with counter @@ -216,9 +224,9 @@ static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe, rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, in_vblank_irq); } while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0); - if (dev->max_vblank_count != 0) { + if (max_vblank_count) { /* trust the hw counter when it's around */ - diff = (cur_vblank - vblank->last) & dev->max_vblank_count; + diff = (cur_vblank - vblank->last) & max_vblank_count; } else if (rc && framedur_ns) { u64 diff_ns = ktime_to_ns(ktime_sub(t_vblank, vblank->time)); @@ -1204,6 +1212,37 @@ void drm_crtc_vblank_reset(struct drm_crtc *crtc) } EXPORT_SYMBOL(drm_crtc_vblank_reset); +/** + * drm_crtc_set_max_vblank_count - configure the hw max vblank counter value + * @crtc: CRTC in question + * @max_vblank_count: max hardware vblank counter value + * + * Update the maximum hardware vblank counter value for @crtc + * at runtime. Useful for hardware where the operation of the + * hardware vblank counter depends on the currently active + * display configuration. + * + * For example, if the hardware vblank counter does not work + * when a specific connector is active the maximum can be set + * to zero. And when that specific connector isn't active the + * maximum can again be set to the appropriate non-zero value. + * + * If used, must be called before drm_vblank_on(). + */ +void drm_crtc_set_max_vblank_count(struct drm_crtc *crtc, + u32 max_vblank_count) +{ + struct drm_device *dev = crtc->dev; + unsigned int pipe = drm_crtc_index(crtc); + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + + WARN_ON(dev->max_vblank_count); + WARN_ON(!READ_ONCE(vblank->inmodeset)); + + vblank->max_vblank_count = max_vblank_count; +} +EXPORT_SYMBOL(drm_crtc_set_max_vblank_count); + /** * drm_crtc_vblank_on - enable vblank events on a CRTC * @crtc: CRTC in question diff --git a/include/drm/drm_device.h b/include/drm/drm_device.h index 42411b3ea0c8..45e43ce9652f 100644 --- a/include/drm/drm_device.h +++ b/include/drm/drm_device.h @@ -184,7 +184,13 @@ struct drm_device { * races and imprecision over longer time periods, hence exposing a * hardware vblank counter is always recommended. * - * If non-zeor, &drm_crtc_funcs.get_vblank_counter must be set. + * This is the statically configured device wide maximum. The driver + * can instead choose to use a runtime configurable per-crtc value + * &drm_vblank_crtc.max_vblank_count, in which case @max_vblank_count + * must be left at zero. See drm_crtc_set_max_vblank_count() on how + * to use the per-crtc value. + * + * If non-zero, &drm_crtc_funcs.get_vblank_counter must be set. */ u32 max_vblank_count; /**< size of vblank counter register */ diff --git a/include/drm/drm_vblank.h b/include/drm/drm_vblank.h index 6ad9630d4f48..e528bb2f659d 100644 --- a/include/drm/drm_vblank.h +++ b/include/drm/drm_vblank.h @@ -128,6 +128,26 @@ struct drm_vblank_crtc { * @last: Protected by &drm_device.vbl_lock, used for wraparound handling. */ u32 last; + /** + * @max_vblank_count: + * + * Maximum value of the vblank registers for this crtc. This value +1 + * will result in a wrap-around of the vblank register. It is used + * by the vblank core to handle wrap-arounds. + * + * If set to zero the vblank core will try to guess the elapsed vblanks + * between times when the vblank interrupt is disabled through + * high-precision timestamps. That approach is suffering from small + * races and imprecision over longer time periods, hence exposing a + * hardware vblank counter is always recommended. + * + * This is the runtime configurable per-crtc maximum set through + * drm_crtc_set_max_vblank_count(). If this is used the driver + * must leave the device wide &drm_device.max_vblank_count at zero. + * + * If non-zero, &drm_crtc_funcs.get_vblank_counter must be set. + */ + u32 max_vblank_count; /** * @inmodeset: Tracks whether the vblank is disabled due to a modeset. * For legacy driver bit 2 additionally tracks whether an additional @@ -206,4 +226,6 @@ bool drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, void drm_calc_timestamping_constants(struct drm_crtc *crtc, const struct drm_display_mode *mode); wait_queue_head_t *drm_crtc_vblank_waitqueue(struct drm_crtc *crtc); +void drm_crtc_set_max_vblank_count(struct drm_crtc *crtc, + u32 max_vblank_count); #endif