From nobody Wed Nov 27 02:28:14 2024 Received: from mx08-00178001.pphosted.com (mx08-00178001.pphosted.com [91.207.212.93]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B230A1EC00D; Tue, 15 Oct 2024 12:16:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.207.212.93 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728994602; cv=none; b=ioko76i/y8tqYjFyaDSrkizQFY8OUf/aL4U7frrH70WaeJOTCenT8IalMverIjD3m1zrnvRubb9dZD2b47Her1holJ4d8Zh+oIKgu51Dd3wb8DQmRSJAeEpKGmBTWEEpnUJiTng1j9X0AC7L6ObvGUlQV0H0kWITlEY7IscF03w= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728994602; c=relaxed/simple; bh=KJJX6Mk2BIPcDHxmAdAAVN4AJzb4fo5uCPsJqP5Eu/0=; h=From:Date:Subject:MIME-Version:Content-Type:Message-ID:References: In-Reply-To:To:CC; b=i6Z+kXiYp3UAWP7dBwxYxVVSUck2HBsYA4XG6+e6u/MkrgXtq2+Nl9sOaIDfnXciBaPnyVmFNOaElQB+cwB9wxWSit+8Mds2hc4o2OR2o39s9OeSpTgm4gQs+O6BwGpI/JLJU/N8NF2szKIMfpSlVNCKWVJiZ+Vr8k+6qlq1r90= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=foss.st.com; spf=pass smtp.mailfrom=foss.st.com; dkim=pass (2048-bit key) header.d=foss.st.com header.i=@foss.st.com header.b=nOcGlcw1; arc=none smtp.client-ip=91.207.212.93 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=foss.st.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=foss.st.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=foss.st.com header.i=@foss.st.com header.b="nOcGlcw1" Received: from pps.filterd (m0369457.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 49FBmlSi018353; Tue, 15 Oct 2024 14:16:16 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h= cc:content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=selector1; bh= rbIrnqQYiSJv3pnlZhdNGe2+XdPzVYU0/oTVXJYKvZg=; b=nOcGlcw1VsnJFLIW Oqk8zgm2Q/Vog9QyUEeK6Bz+rsZbMLXgVGrKWvcp6aP6BduUqdl0w10eYOhwDbLW V0A09IGFxmn+ocHUz5+eXCoIcHLiUrT7MDXiZzNLlaqu7K1cDlLk+R3caa1cFuQi +KljtQ6GdUMsAMXcPT2PJdfcveeVjZcMnBap060lUDe+qyA3hMMyydQUv13FW09R Rcn9sEoMdcZionsMxW0oiECJPvXHZ7OixyTHTFdRkIt02eU8E09HGmMb15t+Nw/8 wYjToD3DwjDocGwTk63lElbzzWKjRbRQWYonLzdRIsB/lpGoGVwuTnCs31LYbnoq qpQNhQ== Received: from beta.dmz-ap.st.com (beta.dmz-ap.st.com [138.198.100.35]) by mx07-00178001.pphosted.com (PPS) with ESMTPS id 42842jacm9-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 15 Oct 2024 14:16:16 +0200 (MEST) Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-ap.st.com (STMicroelectronics) with ESMTP id 07F4940047; Tue, 15 Oct 2024 14:15:29 +0200 (CEST) Received: from Webmail-eu.st.com (shfdag1node3.st.com [10.75.129.71]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id 69C96222351; Tue, 15 Oct 2024 14:14:49 +0200 (CEST) Received: from localhost (10.48.87.35) by SHFDAG1NODE3.st.com (10.75.129.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.37; Tue, 15 Oct 2024 14:14:49 +0200 From: Amelie Delaunay Date: Tue, 15 Oct 2024 14:14:40 +0200 Subject: [PATCH v2 4/9] dt-bindings: dma: stm32-dma3: prevent additional transfers Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-ID: <20241015-dma3-mp25-updates-v2-4-b63e21556ec8@foss.st.com> References: <20241015-dma3-mp25-updates-v2-0-b63e21556ec8@foss.st.com> In-Reply-To: <20241015-dma3-mp25-updates-v2-0-b63e21556ec8@foss.st.com> To: Vinod Koul , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Maxime Coquelin , Alexandre Torgue CC: , , , , , Amelie Delaunay X-Mailer: b4 0.14.2 X-ClientProxiedBy: EQNCAS1NODE4.st.com (10.75.129.82) To SHFDAG1NODE3.st.com (10.75.129.71) X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1039,Hydra:6.0.680,FMLib:17.12.60.29 definitions=2024-09-06_09,2024-09-06_01,2024-09-02_01 stm32-dma3 driver refactors the linked-list in order to address the memory with the highest possible data width. It means that it can introduce up to 2 linked-list items. One with a transfer length multiple of channel maximum burst length and so with the highest possible data width. And an extra one with the latest bytes, with lower data width. Some devices (e.g. FMC ECC) don't support having several transfers instead of only one. So add the possibility to prevent these additional transfers, by setting bit 17 of the 'DMA transfer requirements' bit mask. Signed-off-by: Amelie Delaunay --- Changes in v2: - Reword commit title/message/content as per Rob's suggestion. --- Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml | 3 +++ 1 file changed, 3 insertions(+) diff --git a/Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml= b/Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml index 5484848735f8ac3d2050104bbab1d986e82ba6a7..36f9fe860eb990e6caccedd3146= 0ee6993772a35 100644 --- a/Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml +++ b/Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml @@ -99,6 +99,9 @@ properties: -bit 16: Prevent packing/unpacking mode 0x0: pack/unpack enabled when source data width/burst !=3D desti= nation data width/burst 0x1: memory data width/burst forced to peripheral data width/bur= st to prevent pack/unpack + -bit 17: Prevent additional transfers due to linked-list refactori= ng + 0x0: don't prevent additional transfers for optimal performance + 0x1: prevent additional transfer to accommodate user constraints= such as single transfer =20 required: - compatible --=20 2.25.1