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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 50C49C64E90 for ; Tue, 1 Dec 2020 00:19:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E2230207F7 for ; Tue, 1 Dec 2020 00:19:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="bRI9xPQ6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729632AbgLAATg (ORCPT ); Mon, 30 Nov 2020 19:19:36 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54946 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729464AbgLAATg (ORCPT ); Mon, 30 Nov 2020 19:19:36 -0500 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 15308C0613D2 for ; Mon, 30 Nov 2020 16:18:56 -0800 (PST) Received: from pendragon.ideasonboard.com (62-78-145-57.bb.dnainternet.fi [62.78.145.57]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 9ACBB45D; Tue, 1 Dec 2020 01:18:54 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1606781934; bh=34k77f7FdN4H2ZHL3+aEnNGB4NhXZrHet1Y8lbQPGIQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=bRI9xPQ627ONFqEif3d4774IAGZ8ZdSGWBADY+rJnrLpdcKTnwKwhKpf4OAgW+KXD pWumj7NWk9z6TCWHIkoTag/zcTTZZwqExuW2aemuChEcuzxNB1Z0oVt/uSwo5JZCUf MBtZoSbl6kfV/FApsBNEV9omTRyT6vMO16OchczE= Date: Tue, 1 Dec 2020 02:18:46 +0200 From: Laurent Pinchart To: Tomi Valkeinen Cc: Sebastian Reichel , Nikhil Devshatwar , linux-omap@vger.kernel.org, dri-devel@lists.freedesktop.org, Sekhar Nori , Tony Lindgren , hns@goldelico.com Subject: Re: [PATCH v4 65/80] drm/omap: dsi: skip dsi_vc_enable_hs when already in correct mode Message-ID: <20201201001846.GJ25713@pendragon.ideasonboard.com> References: <20201124124538.660710-1-tomi.valkeinen@ti.com> <20201124124538.660710-66-tomi.valkeinen@ti.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20201124124538.660710-66-tomi.valkeinen@ti.com> Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org Hi Tomi, Thank you for the patch. On Tue, Nov 24, 2020 at 02:45:23PM +0200, Tomi Valkeinen wrote: > Simplify and optimize dsi_vc_enable_hs() so that it can be called > without checking the current HS/LP mode. Make dsi_vc_enable_hs() return > if the VC is already in the correct mode. > > Signed-off-by: Tomi Valkeinen > --- > drivers/gpu/drm/omapdrm/dss/dsi.c | 10 ++++------ > 1 file changed, 4 insertions(+), 6 deletions(-) > > diff --git a/drivers/gpu/drm/omapdrm/dss/dsi.c b/drivers/gpu/drm/omapdrm/dss/dsi.c > index 4ac82166edc3..c3f13226ac26 100644 > --- a/drivers/gpu/drm/omapdrm/dss/dsi.c > +++ b/drivers/gpu/drm/omapdrm/dss/dsi.c > @@ -341,7 +341,6 @@ struct dsi_data { > int irq; > > bool is_enabled; > - bool in_lp_mode; > > struct clk *dss_clk; > struct regmap *syscon; > @@ -2441,6 +2440,9 @@ static void dsi_vc_enable_hs(struct omap_dss_device *dssdev, int vc, > > DSSDBG("dsi_vc_enable_hs(%d, %d)\n", vc, enable); > > + if (REG_GET(dsi, DSI_VC_CTRL(vc), 9, 9) == enable) > + return; > + I tend to prefer cached state instead of reading it back from the hardware, as it's (marginally) more efficient. In either case, Reviewed-by: Laurent Pinchart > WARN_ON(!dsi_bus_is_locked(dsi)); > > dsi_vc_enable(dsi, vc, 0); > @@ -2456,8 +2458,6 @@ static void dsi_vc_enable_hs(struct omap_dss_device *dssdev, int vc, > /* start the DDR clock by sending a NULL packet */ > if (dsi->vm_timings.ddr_clk_always_on && enable) > dsi_vc_send_null(dsi, vc, dsi->dsidev->channel); > - > - dsi->in_lp_mode = !enable; > } > > static void dsi_vc_flush_long_data(struct dsi_data *dsi, int vc) > @@ -4886,9 +4886,7 @@ static ssize_t _omap_dsi_host_transfer(struct dsi_data *dsi, int vc, > struct omap_dss_device *dssdev = &dsi->output; > int r; > > - if (!!(msg->flags & MIPI_DSI_MSG_USE_LPM) != dsi->in_lp_mode) > - dsi_vc_enable_hs(dssdev, vc, > - !(msg->flags & MIPI_DSI_MSG_USE_LPM)); > + dsi_vc_enable_hs(dssdev, vc, !(msg->flags & MIPI_DSI_MSG_USE_LPM)); > > switch (msg->type) { > case MIPI_DSI_GENERIC_SHORT_WRITE_0_PARAM: -- Regards, Laurent Pinchart