From patchwork Tue Jul 19 16:30:55 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: cpaul@redhat.com X-Patchwork-Id: 9237827 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 A03AF602F0 for ; Tue, 19 Jul 2016 16:31:38 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 91A1A26B4A for ; Tue, 19 Jul 2016 16:31:38 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8634C26E81; Tue, 19 Jul 2016 16:31:38 +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]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F344D26B4A for ; Tue, 19 Jul 2016 16:31:37 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 9AA456E6C7; Tue, 19 Jul 2016 16:31:34 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by gabe.freedesktop.org (Postfix) with ESMTPS id 6C1816E6C4; Tue, 19 Jul 2016 16:31:13 +0000 (UTC) Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 4913E769E5; Tue, 19 Jul 2016 16:31:12 +0000 (UTC) Received: from ecstaticemu.bos.redhat.com (dhcp-25-142.bos.redhat.com [10.18.25.142]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u6JGV805013249; Tue, 19 Jul 2016 12:31:11 -0400 From: Lyude To: intel-gfx@lists.freedesktop.org Subject: [PATCH 1/2] drm/i915/skl: Update plane watermarks atomically during plane updates Date: Tue, 19 Jul 2016 12:30:55 -0400 Message-Id: <1468945856-23126-2-git-send-email-cpaul@redhat.com> In-Reply-To: <1468945856-23126-1-git-send-email-cpaul@redhat.com> References: <1468945856-23126-1-git-send-email-cpaul@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.68 on 10.5.11.27 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Tue, 19 Jul 2016 16:31:13 +0000 (UTC) Cc: Radhakrishna Sripada , "open list:INTEL DRM DRIVERS excluding Poulsbo, Moorestow..., linux-kernel@vger.kernel.org open list" , stable@vger.kernel.org, Daniel Vetter , Lyude X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP Thanks to Ville for suggesting this as a potential solution to pipe underruns on Skylake. On Skylake all of the registers for configuring planes, including the registers for configuring their watermarks, are double buffered. New values written to them won't take effect until said registers are "armed", which is done by writing to the PLANE_SURF (or in the case of cursor planes, the CURBASE register) register. With this in mind, up until now we've been updating watermarks on skl like this: - Calculate new watermark values in skl_compute_wm() - Update non-watermark settings for each plane in skylake_update_primary_plane()/i9xx_update_cursor() - Arm plane registers to update at the start of the next vblank in skylake_update_primary_plane()/i9xx_update_cursor() - *Possibly underrun here, since the plane may now have updated it's settings using the old and insufficient watermark values* - Update watermark settings in skl_write_wm_values() - *Possibly underrun here as well if we've passed a vblank, causing the hardware to get stuck running on intermediate wm values* - Finally arm plane registers so they update to the correct values at the start of the next vblank in skl_wm_flush_pipe() Now we update watermarks atomically like this: - Calculate new watermark values in skl_compute_wm() - Update watermark values for each plane in skylake_write_plane_wm()/skylake_write_cursor_wm() - Update all the other values for the plane (position, address, etc.) in skylake_update_primary_plane()/i9xx_update_cursor() - Arm plane registers (including the watermark settings) to update at the start of the next vblank in skylake_update_primary_plane()/i9xx_update_cursor() Which is more of a step in the right direction to fixing all of the underrun issues we're currently seeing with skl Signed-off-by: Lyude Paul Cc: stable@vger.kernel.org Cc: Ville Syrjälä Cc: Daniel Vetter Cc: Radhakrishna Sripada Cc: Hans de Goede Cc: Matt Roper --- drivers/gpu/drm/i915/intel_display.c | 47 ++++++++++++++++++++++++++++++++++++ drivers/gpu/drm/i915/intel_pm.c | 15 +----------- 2 files changed, 48 insertions(+), 14 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index fb7d8fc5..3d2c125 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -2971,6 +2971,27 @@ u32 skl_plane_ctl_rotation(unsigned int rotation) return 0; } +static void skylake_write_plane_wm(struct intel_crtc *intel_crtc, + int plane) +{ + struct drm_crtc *crtc = &intel_crtc->base; + struct drm_device *dev = crtc->dev; + struct drm_i915_private *dev_priv = to_i915(dev); + struct skl_wm_values *wm = &dev_priv->wm.skl_results; + int level, max_level = ilk_wm_max_level(dev); + enum pipe pipe = intel_crtc->pipe; + + mutex_lock(&dev_priv->wm.wm_mutex); + + for (level = 0; level < max_level; level++) { + I915_WRITE(PLANE_WM(pipe, plane, level), + wm->plane[pipe][plane][level]); + } + I915_WRITE(PLANE_WM_TRANS(pipe, plane), wm->plane_trans[pipe][plane]); + + mutex_unlock(&dev_priv->wm.wm_mutex); +} + static void skylake_update_primary_plane(struct drm_plane *plane, const struct intel_crtc_state *crtc_state, const struct intel_plane_state *plane_state) @@ -3031,6 +3052,8 @@ static void skylake_update_primary_plane(struct drm_plane *plane, intel_crtc->adjusted_x = x_offset; intel_crtc->adjusted_y = y_offset; + skylake_write_plane_wm(intel_crtc, 0); + I915_WRITE(PLANE_CTL(pipe, 0), plane_ctl); I915_WRITE(PLANE_OFFSET(pipe, 0), plane_offset); I915_WRITE(PLANE_SIZE(pipe, 0), plane_size); @@ -10233,6 +10256,27 @@ static void i845_update_cursor(struct drm_crtc *crtc, u32 base, } } +static void skl_write_cursor_wm(struct intel_crtc *intel_crtc) +{ + struct drm_crtc *crtc = &intel_crtc->base; + struct drm_device *dev = crtc->dev; + struct drm_i915_private *dev_priv = to_i915(dev); + struct skl_wm_values *wm = &dev_priv->wm.skl_results; + int level, max_level = ilk_wm_max_level(dev); + enum pipe pipe = intel_crtc->pipe; + + mutex_lock(&dev_priv->wm.wm_mutex); + + for (level = 0; level <= max_level; level++) { + I915_WRITE(CUR_WM(pipe, level), + wm->plane[pipe][PLANE_CURSOR][level]); + } + I915_WRITE(CUR_WM_TRANS(pipe), + wm->plane_trans[pipe][PLANE_CURSOR]); + + mutex_unlock(&dev_priv->wm.wm_mutex); +} + static void i9xx_update_cursor(struct drm_crtc *crtc, u32 base, const struct intel_plane_state *plane_state) { @@ -10242,6 +10286,9 @@ static void i9xx_update_cursor(struct drm_crtc *crtc, u32 base, int pipe = intel_crtc->pipe; uint32_t cntl = 0; + if (IS_SKYLAKE(dev_priv)) + skl_write_cursor_wm(intel_crtc); + if (plane_state && plane_state->visible) { cntl = MCURSOR_GAMMA_ENABLE; switch (plane_state->base.crtc_w) { diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 213ad35..3a7709c 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -3788,7 +3788,7 @@ static void skl_write_wm_values(struct drm_i915_private *dev_priv, skl_disable_sagv(dev_priv); for_each_intel_crtc(dev, crtc) { - int i, level, max_level = ilk_wm_max_level(dev); + int i; enum pipe pipe = crtc->pipe; if ((new->dirty_pipes & drm_crtc_mask(&crtc->base)) == 0) @@ -3798,19 +3798,6 @@ static void skl_write_wm_values(struct drm_i915_private *dev_priv, I915_WRITE(PIPE_WM_LINETIME(pipe), new->wm_linetime[pipe]); - for (level = 0; level <= max_level; level++) { - for (i = 0; i < intel_num_planes(crtc); i++) - I915_WRITE(PLANE_WM(pipe, i, level), - new->plane[pipe][i][level]); - I915_WRITE(CUR_WM(pipe, level), - new->plane[pipe][PLANE_CURSOR][level]); - } - for (i = 0; i < intel_num_planes(crtc); i++) - I915_WRITE(PLANE_WM_TRANS(pipe, i), - new->plane_trans[pipe][i]); - I915_WRITE(CUR_WM_TRANS(pipe), - new->plane_trans[pipe][PLANE_CURSOR]); - for (i = 0; i < intel_num_planes(crtc); i++) { skl_ddb_entry_write(dev_priv, PLANE_BUF_CFG(pipe, i),