From patchwork Thu Nov 19 12:02:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Damien Le Moal X-Patchwork-Id: 328872 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=-16.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 99727C388F9 for ; Thu, 19 Nov 2020 12:03:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3B24B20709 for ; Thu, 19 Nov 2020 12:03:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=permerror (0-bit key) header.d=wdc.com header.i=@wdc.com header.b="OG9OwEbF" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725877AbgKSMDA (ORCPT ); Thu, 19 Nov 2020 07:03:00 -0500 Received: from esa2.hgst.iphmx.com ([68.232.143.124]:54227 "EHLO esa2.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726495AbgKSMDA (ORCPT ); Thu, 19 Nov 2020 07:03:00 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com; t=1605788066; x=1637324066; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=wf/FejK7z/uXHb5mg4MRAl9M/wAxMVeO8inZ9o+YmVY=; b=OG9OwEbFSpG5ychOL/p3o3ITZDA2zhE8TBTJNX+hiQXHznYZWaK7L5f4 qRzwBY6ycxdjyxkYOV2gdIe+07hTjPhlonRYIgjEa8wevFxaHd04mqioo 6QHNV3GR0vL/Hy4oH//cfRQ4jm7qmJiY3ccafLhMBsQOQKSwMoeHZ9D8q aZX77BxKEF44LXBrAOgI/Zye/Dl4/2h1NMfpYhmfPkZqgC4zCyvOAUWT8 LE852WP6lQbtSQkcMxUIAL8PwNyPpjbpTnnTYxujMVE2sWHQpPJYvdThz dRQuXnK0uAY6ZeOM/eKx0DHrJvHcptbwy7Xg4TogDEf5Rjyd3RKVvikUH A==; IronPort-SDR: N1tdo7cl+Csp5PBfq94U/uTYD6IpgqMoxDXuzbD5o2Zlv0w2ALzY+6PGPbyl6kSCaohethr9PU fR+vz8Ewe/NleH/HcjApSRIt77lxAYZBi0EQNPA/MWbHxvvvPU6m40a7/zShzveKd82H4ZmlTR SUxSwR79YRARXR3OExx5xqhNxkYUTVHqJMXLyTC5mdKlB/CyfZoseLtiKIzzOSJAkDRHFd3hP7 1vf6Y81j8YMhjc0w6k+EF1DJguJMP0t+DF/aPVb/psb/pzy8RgJSNQWGZYWPb2pI7wurNUyDic BvM= X-IronPort-AV: E=Sophos;i="5.77,490,1596470400"; d="scan'208";a="256574393" Received: from h199-255-45-14.hgst.com (HELO uls-op-cesaep01.wdc.com) ([199.255.45.14]) by ob1.hgst.iphmx.com with ESMTP; 19 Nov 2020 20:14:26 +0800 IronPort-SDR: Dnao9rPBKzXZ7Up6pFchtEMYdKpECWtURLOP4rCrZyJH8WsJNTkJ7EudL/8WrqiLv3h1AROixk RmZQiSdmigFaoNmW9BadrqshV4UEMMh/gudMXkqDot6rnbqEzOY3D5sV8ul04nWcJYgEr+xQmQ FgSHSt1hv4PxPABrKWPjwNDWwTD8xg1GfaS8gS8VbyXObpyvf+Jby/vE4FOZqaG9VfRvMqdxbq +uss2JQnWB74LMyh2I/pnwayNkE+zBfywSkVSed838zWu8lcnTeyaNCsI9yXmEtW0QHLljHsyy xAxh2CUDVZ5U6dXwrtoTmVw2 Received: from uls-op-cesaip02.wdc.com ([10.248.3.37]) by uls-op-cesaep01.wdc.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Nov 2020 03:48:50 -0800 IronPort-SDR: zHCA1ONG6vlEoq0lAABzvdDNqSfm49/xsrGsNDv7ydyxpA18pc49ucJDWTdQvIBiiAoYBXdV17 d7bzRn25uklSCOxP+UJ/gabd4zPoC4OnnG+xrA7PEIordKorNWly5RdNug5JRuDQJGCdICWXu0 RSGFKzyYQgpYBOWbIuqlHsLGKFbNc28D8Vzs9y8M1sNiEygw2Ak4DZ/xAwZG8LRRJsz+9Re4nY JckWw3FnoowHWMuZKB2aAMiEBR41QJFBTlWVQsDzZTRIDitVT8zgkueGpcZdl2cPC3qqHndIiB VcE= WDCIronportException: Internal Received: from jfklab-fym3sg2.ad.shared (HELO twashi.fujisawa.hgst.com) ([10.84.71.107]) by uls-op-cesaip02.wdc.com with ESMTP; 19 Nov 2020 04:02:59 -0800 From: Damien Le Moal To: Serge Semin , Mark Brown , linux-spi@vger.kernel.org, Rob Herring , devicetree@vger.kernel.org Cc: Sean Anderson Subject: [PATCH 2/3] spi: dw: Add support for the Canaan K210 SoC SPI Date: Thu, 19 Nov 2020 21:02:52 +0900 Message-Id: <20201119120253.390883-3-damien.lemoal@wdc.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201119120253.390883-1-damien.lemoal@wdc.com> References: <20201119120253.390883-1-damien.lemoal@wdc.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org The Canaan Kendryte K210 RISC-V SoC includes a DW apb_ssi v4 controller which is documented to have a 32 words deep TX and RX FIFO. The FIFO length detection in spi_hw_init() correctly detects this value. However, when the controller RX FIFO is filled up to 32 entries (RXFLR = 32), an RX FIFO overrun error occurs. This likely due to a hardware bug which can be avoided by force setting the fifo_len field of struct dw_spi to 31. Define the dw_spi_canaan_k210_init() function to force set fifo_len to 31 when the device node compatible string is "canaan,k210-spi". Signed-off-by: Damien Le Moal Acked-by: Serge Semin --- drivers/spi/spi-dw-mmio.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/spi/spi-dw-mmio.c b/drivers/spi/spi-dw-mmio.c index d0cc5bf4fa4e..17c06039a74d 100644 --- a/drivers/spi/spi-dw-mmio.c +++ b/drivers/spi/spi-dw-mmio.c @@ -222,6 +222,21 @@ static int dw_spi_keembay_init(struct platform_device *pdev, return 0; } +static int dw_spi_canaan_k210_init(struct platform_device *pdev, + struct dw_spi_mmio *dwsmmio) +{ + /* + * The Canaan Kendryte K210 SoC DW apb_ssi v4 spi controller is + * documented to have a 32 word deep TX and RX FIFO, which + * spi_hw_init() detects. However, when the RX FIFO is filled up to + * 32 entries (RXFLR = 32), an RX FIFO overrun error occurs. Avoid this + * problem by force setting fifo_len to 31. + */ + dwsmmio->dws.fifo_len = 31; + + return 0; +} + static int dw_spi_mmio_probe(struct platform_device *pdev) { int (*init_func)(struct platform_device *pdev, @@ -335,6 +350,7 @@ static const struct of_device_id dw_spi_mmio_of_match[] = { { .compatible = "snps,dwc-ssi-1.01a", .data = dw_spi_dwc_ssi_init}, { .compatible = "intel,keembay-ssi", .data = dw_spi_keembay_init}, { .compatible = "microchip,sparx5-spi", dw_spi_mscc_sparx5_init}, + { .compatible = "canaan,k210-spi", dw_spi_canaan_k210_init}, { /* end of table */} }; MODULE_DEVICE_TABLE(of, dw_spi_mmio_of_match);