From patchwork Mon Mar 7 16:18:19 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Boris BREZILLON X-Patchwork-Id: 8520841 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 56BE3C0553 for ; Mon, 7 Mar 2016 16:21:26 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 7DE7D20270 for ; Mon, 7 Mar 2016 16:21:25 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id A94502021B for ; Mon, 7 Mar 2016 16:21:24 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1acxsD-0008IP-Hg; Mon, 07 Mar 2016 16:19:09 +0000 Received: from down.free-electrons.com ([37.187.137.238] helo=mail.free-electrons.com) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1acxs0-0008AJ-Uh; Mon, 07 Mar 2016 16:18:57 +0000 Received: by mail.free-electrons.com (Postfix, from userid 110) id 932B3263; Mon, 7 Mar 2016 17:18:35 +0100 (CET) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 Received: from localhost.localdomain (AToulouse-657-1-1129-172.w92-156.abo.wanadoo.fr [92.156.51.172]) by mail.free-electrons.com (Postfix) with ESMTPSA id 3B9A81C2; Mon, 7 Mar 2016 17:18:35 +0100 (CET) From: Boris Brezillon To: David Woodhouse , Brian Norris , linux-mtd@lists.infradead.org Subject: [PATCH 02/16] mtd: nand: sunxi: fix clk rate calculation Date: Mon, 7 Mar 2016 17:18:19 +0100 Message-Id: <1457367513-26069-3-git-send-email-boris.brezillon@free-electrons.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1457367513-26069-1-git-send-email-boris.brezillon@free-electrons.com> References: <1457367513-26069-1-git-send-email-boris.brezillon@free-electrons.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160307_081857_292760_36E83EB0 X-CRM114-Status: GOOD ( 11.52 ) X-Spam-Score: -1.9 (-) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Boris Brezillon , Chen-Yu Tsai , linux-kernel@vger.kernel.org, linux-sunxi@googlegroups.com, Maxime Ripard , linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP Unlike what is specified in the Allwinner datasheets, the NAND clock rate is not equal to 2/T but 1/T. Fix the clock rate selection accordingly. Signed-off-by: Boris Brezillon --- drivers/mtd/nand/sunxi_nand.c | 8 +------- 1 file changed, 1 insertion(+), 7 deletions(-) diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c index 4d01e65..ab66d8d 100644 --- a/drivers/mtd/nand/sunxi_nand.c +++ b/drivers/mtd/nand/sunxi_nand.c @@ -1208,13 +1208,7 @@ static int sunxi_nand_chip_set_timings(struct sunxi_nand_chip *chip, /* Convert min_clk_period from picoseconds to nanoseconds */ min_clk_period = DIV_ROUND_UP(min_clk_period, 1000); - /* - * Convert min_clk_period into a clk frequency, then get the - * appropriate rate for the NAND controller IP given this formula - * (specified in the datasheet): - * nand clk_rate = 2 * min_clk_rate - */ - chip->clk_rate = (2 * NSEC_PER_SEC) / min_clk_period; + chip->clk_rate = NSEC_PER_SEC / min_clk_period; return 0; }