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 X-Spam-Level: X-Spam-Status: No, score=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1186FC46471 for ; Tue, 7 Aug 2018 18:29:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B7F612172F for ; Tue, 7 Aug 2018 18:29:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=agner.ch header.i=@agner.ch header.b="gaV4311d" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B7F612172F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=agner.ch Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389160AbeHGUp3 (ORCPT ); Tue, 7 Aug 2018 16:45:29 -0400 Received: from mail.kmu-office.ch ([178.209.48.109]:40478 "EHLO mail.kmu-office.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727198AbeHGUp2 (ORCPT ); Tue, 7 Aug 2018 16:45:28 -0400 Received: from webmail.kmu-office.ch (unknown [IPv6:2a02:418:6a02::a3]) by mail.kmu-office.ch (Postfix) with ESMTPSA id F403F5C06FF; Tue, 7 Aug 2018 20:29:43 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=agner.ch; s=dkim; t=1533666584; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=S62vADfBXX354dpQ+IHYX5OujZri7yKBVtSt3wuz1uI=; b=gaV4311d9FYuDfyTKHJFUz2zbyb3+IyWecD3mRvoJE8oXrBz6WbJftPQISWy+ljEVSjeqo 5L/jbDaNPOrUkI8plnS5nkNdgspQyKJYXmH7qjJDfu9s6fXvA8iA/Fo8PRiKYgVHlcfE93 48D/LpGjbD4T9InG2Q3JtDMebLDPVoo= MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Date: Tue, 07 Aug 2018 20:29:43 +0200 From: Stefan Agner To: Leonard Crestez Cc: Philipp Zabel , Marek Vasut , Shawn Guo , Fabio Estevam , Robert Chiras , Mirela Rabulea , Anson Huang , dri-devel@lists.freedesktop.org, Dong Aisheng , linux-imx@nxp.com, kernel@pengutronix.de, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 1/4] drm/mxsfb: Fix initial corrupt frame when activating display In-Reply-To: References: Message-ID: X-Sender: stefan@agner.ch User-Agent: Roundcube Webmail/1.3.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06.08.2018 21:31, Leonard Crestez wrote: > LCDIF will repeatedly display data from CUR_BUF and set CUR_BUF to > NEXT_BUF when done. Since we are only ever writing to NEXT_BUF the > display will show an initial corrupt frame. > > Fix by writing the FB paddr to both CUR_BUF and NEXT_BUF when > activating the CRTC. Really like how this patch set evolves! Only some minor thing below... > > Signed-off-by: Leonard Crestez > --- > drivers/gpu/drm/mxsfb/mxsfb_crtc.c | 42 +++++++++++++++++++++--------- > 1 file changed, 29 insertions(+), 13 deletions(-) > > diff --git a/drivers/gpu/drm/mxsfb/mxsfb_crtc.c > b/drivers/gpu/drm/mxsfb/mxsfb_crtc.c > index 0abe77675b76..db3ff5bde122 100644 > --- a/drivers/gpu/drm/mxsfb/mxsfb_crtc.c > +++ b/drivers/gpu/drm/mxsfb/mxsfb_crtc.c > @@ -194,15 +194,31 @@ static int mxsfb_reset_block(void __iomem *reset_addr) > return ret; > > return clear_poll_bit(reset_addr, MODULE_CLKGATE); > } > > +static dma_addr_t mxsfb_get_fb_paddr(struct mxsfb_drm_private *mxsfb) > +{ > + struct drm_framebuffer *fb = mxsfb->pipe.plane.state->fb; > + struct drm_gem_cma_object *gem; > + > + if (!fb) > + return 0; > + > + gem = drm_fb_cma_get_gem_obj(fb, 0); > + if (!gem) > + return 0; > + > + return gem->paddr; > +} > + > static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb) > { > struct drm_display_mode *m = &mxsfb->pipe.crtc.state->adjusted_mode; > const u32 bus_flags = mxsfb->connector.display_info.bus_flags; > u32 vdctrl0, vsync_pulse_len, hsync_pulse_len; > + dma_addr_t paddr; > int err; > > /* > * It seems, you can't re-program the controller if it is still > * running. This may lead to shifted pictures (FIFO issue?), so > @@ -268,10 +284,16 @@ static void mxsfb_crtc_mode_set_nofb(struct > mxsfb_drm_private *mxsfb) > mxsfb->base + LCDC_VDCTRL3); > > writel(SET_DOTCLK_H_VALID_DATA_CNT(m->hdisplay), > mxsfb->base + LCDC_VDCTRL4); > > + /* Update cur_buf as well to avoid an initial corrupt frame */ > + paddr = mxsfb_get_fb_paddr(mxsfb); > + if (paddr) { > + writel(paddr, mxsfb->base + mxsfb->devdata->cur_buf); > + writel(paddr, mxsfb->base + mxsfb->devdata->next_buf); > + } Traditionally mxsfb_crtc_mode_set_nofb() was used as a callback to mode_set_nofb. And that callback should not fiddle with the fb (as the name says). So I rather prefer to move the new bits to mxsfb_crtc_enable(), between mxsfb_crtc_mode_set_nofb() and mxsfb_enable_controller(). It is only cosmetics, but I'd rather prefer to have it in the right place. Currently the AXI clock is disabled between those functions... I suggest to enable the AXI clock once in mxsfb_crtc_enable(). This puts an end to the unnecessary enable/disable/enable sequence in mxsfb_crtc_enable(). So I suggest to create a patch "drm/mxsfb: simplify AXI clock handling" --- a/drivers/gpu/drm/mxsfb/mxsfb_crtc.c +++ b/drivers/gpu/drm/mxsfb/mxsfb_crtc.c @@ -129,7 +129,6 @@ static void mxsfb_enable_controller(struct mxsfb_drm_private *mxsfb) if (mxsfb->clk_disp_axi) clk_prepare_enable(mxsfb->clk_disp_axi); clk_prepare_enable(mxsfb->clk); - mxsfb_enable_axi_clk(mxsfb); /* If it was disabled, re-enable the mode again */ writel(CTRL_DOTCLK_MODE, mxsfb->base + LCDC_CTRL + REG_SET); @@ -159,8 +158,6 @@ static void mxsfb_disable_controller(struct mxsfb_drm_private *mxsfb) reg &= ~VDCTRL4_SYNC_SIGNALS_ON; writel(reg, mxsfb->base + LCDC_VDCTRL4); - mxsfb_disable_axi_clk(mxsfb); - clk_disable_unprepare(mxsfb->clk); if (mxsfb->clk_disp_axi) clk_disable_unprepare(mxsfb->clk_disp_axi); @@ -208,7 +205,6 @@ static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb) * running. This may lead to shifted pictures (FIFO issue?), so * first stop the controller and drain its FIFOs. */ - mxsfb_enable_axi_clk(mxsfb); /* Mandatory eLCDIF reset as per the Reference Manual */ err = mxsfb_reset_block(mxsfb->base); @@ -269,12 +265,11 @@ static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb) writel(SET_DOTCLK_H_VALID_DATA_CNT(m->hdisplay), mxsfb->base + LCDC_VDCTRL4); - - mxsfb_disable_axi_clk(mxsfb); } void mxsfb_crtc_enable(struct mxsfb_drm_private *mxsfb) { + mxsfb_enable_axi_clk(mxsfb); mxsfb_crtc_mode_set_nofb(mxsfb); mxsfb_enable_controller(mxsfb); } @@ -282,6 +277,7 @@ void mxsfb_crtc_enable(struct mxsfb_drm_private *mxsfb) void mxsfb_crtc_disable(struct mxsfb_drm_private *mxsfb) { mxsfb_disable_controller(mxsfb); + mxsfb_disable_axi_clk(mxsfb); } Then move the above section between mxsfb_crtc_mode_set_nofb() and mxsfb_enable_controller(). -- Stefan > mxsfb_disable_axi_clk(mxsfb); > } > > void mxsfb_crtc_enable(struct mxsfb_drm_private *mxsfb) > { > @@ -287,16 +309,12 @@ void mxsfb_crtc_disable(struct mxsfb_drm_private *mxsfb) > void mxsfb_plane_atomic_update(struct mxsfb_drm_private *mxsfb, > struct drm_plane_state *state) > { > struct drm_simple_display_pipe *pipe = &mxsfb->pipe; > struct drm_crtc *crtc = &pipe->crtc; > - struct drm_framebuffer *fb = pipe->plane.state->fb; > struct drm_pending_vblank_event *event; > - struct drm_gem_cma_object *gem; > - > - if (!crtc) > - return; > + dma_addr_t paddr; > > spin_lock_irq(&crtc->dev->event_lock); > event = crtc->state->event; > if (event) { > crtc->state->event = NULL; > @@ -307,14 +325,12 @@ void mxsfb_plane_atomic_update(struct > mxsfb_drm_private *mxsfb, > drm_crtc_send_vblank_event(crtc, event); > } > } > spin_unlock_irq(&crtc->dev->event_lock); > > - if (!fb) > - return; > - > - gem = drm_fb_cma_get_gem_obj(fb, 0); > - > - mxsfb_enable_axi_clk(mxsfb); > - writel(gem->paddr, mxsfb->base + mxsfb->devdata->next_buf); > - mxsfb_disable_axi_clk(mxsfb); > + paddr = mxsfb_get_fb_paddr(mxsfb); > + if (paddr) { > + mxsfb_enable_axi_clk(mxsfb); > + writel(paddr, mxsfb->base + mxsfb->devdata->next_buf); > + mxsfb_disable_axi_clk(mxsfb); > + } > }