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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B30D3C3DA7D for ; Tue, 3 Jan 2023 14:59:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=fTx3HumTEiP4NlhV9D0SvZQk+2uTQlCTyX5VcWcpFzY=; b=OoE3mgzvZMrtaw frTjeLE8SHX9Q06npLSS9hh6GyeT/DGnmRhAaHveCBkx1yzKUYKTZJKwGJRnxOLzW4pnpjlHd5Y3b i0Agr1X8n/4mGRwgy7WofZ4D6qSj4WMRK87FKn8bZ4crIY1MEwJlvKYRKxov2Vhm+OoQm7Eol4hw8 AD+buuMqAYOokoEeslUiikG8jsHCh6jGs/wTSxZMe5/4wjZMDo0oUlZlku3zALwUS+NOmIuaqK5xY aWrDIKmM/9yHuYJZrZ0UHplLaMJVYeKyoGYcuvMthINaxfgG5ufhA+SMragYAgduM0+IOC5EfdzCE 41FV/3YmtYYOgbbMcFfQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pCiju-002Cb2-Ag; Tue, 03 Jan 2023 14:58:10 +0000 Received: from mx1.tq-group.com ([93.104.207.81]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1pCdxb-000YAl-LT for linux-arm-kernel@lists.infradead.org; Tue, 03 Jan 2023 09:51:58 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tq-group.com; i=@tq-group.com; q=dns/txt; s=key1; t=1672739515; x=1704275515; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=HaOHD/dXS68xXURn+R9LoVsKFBSgwemRrONqLSwdBjc=; b=V6I9uRW5ai8EJj+UxyhQ7+YQtrKLcLyPMD3aee6lcOocfdXsSuK6HKhj Xd66DXFW3UgMeXl+ahtsAkGRTbKHCMBv3gt1glNmMQbmyZC/nStwQtHeE EAFpRJpXbjLKNP9a6AnjDKGFES3YmbXcDb7pxMkddEcceQj71ZTGaduGE EooeZf0XfCoCf/vjYqj2VjNVVuvcOCAMH5qw4QKXRGBg6iRG1PhOvPrcU stLuPhITyLGvwgMsM1fGxkvabmk/QrmATDJWHLr8X3RhUS/UMkhVoFy6v oueyPjFVVzWDt1zUThYEXtysWJI4R8sfqt0Y+FJyEYj9s5p6pO0WdjdCD A==; X-IronPort-AV: E=Sophos;i="5.96,296,1665439200"; d="scan'208";a="28217837" Received: from unknown (HELO tq-pgp-pr1.tq-net.de) ([192.168.6.15]) by mx1-pgp.tq-group.com with ESMTP; 03 Jan 2023 10:51:47 +0100 Received: from mx1.tq-group.com ([192.168.6.7]) by tq-pgp-pr1.tq-net.de (PGP Universal service); Tue, 03 Jan 2023 10:51:47 +0100 X-PGP-Universal: processed; by tq-pgp-pr1.tq-net.de on Tue, 03 Jan 2023 10:51:47 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tq-group.com; i=@tq-group.com; q=dns/txt; s=key1; t=1672739507; x=1704275507; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=HaOHD/dXS68xXURn+R9LoVsKFBSgwemRrONqLSwdBjc=; b=QHbb0E41O1umG0uCnQ5Fy6UNxUpCtrGLEIsoHgDmPE0hJgZtkwvbVJXt 1cvAPJ17LC6UYdr1IOUOaJjUUbPgxJzw82NU7noJlVFT9HbSlIL230lmQ /vW24sKxbwcCCPpzJNnSmHD2g8+NQxnbe0Fuz+mhsRwB9AiUlTFQhdoc7 35avELVf7SdtZbv/NswwojGUum+DRyFGZHYNIyxE2U4nm6m+7wxxCWY2m 7VdQAE3y4/X1v6R/x9ZO+jr/sU6Q7TMyL2dtbYlQ7RB3oy4k/iy53t5nz X6t3zu5Q6FPa11K+zNZAopmR5GPK7S9gYAg9W4kWsdXGcrdC7lBDIpQY0 Q==; X-IronPort-AV: E=Sophos;i="5.96,296,1665439200"; d="scan'208";a="28217836" Received: from vtuxmail01.tq-net.de ([10.115.0.20]) by mx1.tq-group.com with ESMTP; 03 Jan 2023 10:51:47 +0100 Received: from steina-w.localnet (unknown [10.123.53.21]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by vtuxmail01.tq-net.de (Postfix) with ESMTPSA id C74FB280056; Tue, 3 Jan 2023 10:51:46 +0100 (CET) From: Alexander Stein To: Andrzej Hajda , Inki Dae , Marek Szyprowski , Joonyoung Shim , Seung-Woo Kim , Kyungmin Park , Frieder Schrempf , Fancy Fang , Tim Harvey , Michael Nazzareno Trimarchi , Adam Ford , Neil Armstrong , Robert Foss , Laurent Pinchart , Tommaso Merciai , "dri-devel@lists.freedesktop.org" , Marek Vasut Cc: "linux-samsung-soc@vger.kernel.org" , Matteo Lisi , NXP Linux Team , linux-amarula , "linux-arm-kernel@lists.infradead.org" , Jagan Teki Subject: Re: [PATCH v10 00/18] drm: Add Samsung MIPI DSIM bridge Date: Tue, 03 Jan 2023 10:51:44 +0100 Message-ID: <1983452.PIDvDuAF1L@steina-w> Organization: TQ-Systems GmbH In-Reply-To: References: MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230103_015156_212022_2E9F9A1D X-CRM114-Status: GOOD ( 26.46 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Marek, Am Sonntag, 18. Dezember 2022, 00:55:57 CET schrieb Marek Vasut: > On 12/16/22 14:25, Alexander Stein wrote: > Hi, > > [...] > > > Oh, nice, thanks for the pointer. When setting > > > >> samsung,burst-clock-frequency = <668250000>; > > > > in imx8mm.dtsi > > I get a non-flickering display using 4 lanes. Although admittedly this is > > just random guessing. I'm not sure which clock exactly has to be in the > > range CHA_DSI_CLK_RANGE is configured to. With 4 lanes SN65DSI84 is > > configured for> > > 205-210 MHz (0x29), while I get these PLL PMS settings on DSIM: > >> samsung-dsim 32e10000.dsi: PLL freq 668250000, (p 4, m 99, s 0) > >> samsung-dsim 32e10000.dsi: hs_clk = 668250000, byte_clk = 83531250, > >> esc_clk > > > > = 16706250 > > If I recall it right, minimum PLL frequency is: > > fPMS=1.2*width*height*bpp*fps=1.2*800*480*24*60=663.5 MHz > > the link frequency is then > > fHS=fPMS/lanes/2=82.9 MHz (on the DDR clock lane) Mh, there is something bogus about this. Right now the PLL freq is set depending on 'samsung,burst-clock-frequency' property. But this actually is somehow depending on the number of lanes I configure. From the debug output hs_clk and PLL freq are identical. AFAICS there is also no divider from PLL to hs_clk in the register map. > So DSI83 should be in the range of 80..85 MHz input clock if I calculate > this right. Can you check what is the value of mode->clock, the > mipi_dsi_panel_format_to_bpp() return value, ctx->dsi->lanes in dsi83 > sm65dsi83_get_dsi_range() ? A working setup on a tianma,tm070jvhg33 display (1280x800) is: > samsung-dsim 32e10000.dsi: PLL freq 891000000, (p 3, m 99, s 0) > samsung-dsim 32e10000.dsi: hs_clk = 891000000, byte_clk = 111375000, esc_clk = 18562500 > sn65dsi83 2-002d: mode->clock: 68200 > sn65dsi83 2-002d: mode bpp: 24 > sn65dsi83 2-002d: ctx->dsi->lanes: 3 > sn65dsi83 2-002d: samsung_dsim_set_pll: 0x37 Calculating backwards, sn64dsi83 is expecting a clock in the range of 275-280 MHz. But I fail to see a corresponding clock in the DSIM PLL configuration. Best regards, Alexander > > AFAICS DSIM bridge is configurung hs_clk, byte_clk and esc_clk just from > > DT > > properties, while SN65DSI84 is using display mode and number of lanes. > > > > Is it expected that the DSIM PLL frequencies are set in DT for a specific > > bridge/display setup? > > No, there should be negotiation between the host and bridge/panel, I > tried to propose two variants, but they were all rejected. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel