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=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED autolearn=ham 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 8BC28C169C4 for ; Thu, 31 Jan 2019 16:55:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 50755218EA for ; Thu, 31 Jan 2019 16:55:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548953749; bh=5InK5VVpqOh9e3SQsYJHpCS38H6ABMfXKqzoKGLxjl8=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=CywE/ZfW0Q6zBlSj8xc2TdPwljg1UAWNCAcGII6xP0j1vTrxtKI1PnLD7ogAXDY42 Qb2+1bPKgO0TO/Npm3qDWlqF3UK6nCLBkDWOu1jZzMZRdRyephUiLQaHImvLkY9V94 pH9MJsUxKmoGxUoWLUAVJBzX0mS/lYA6+938NKCU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387676AbfAaQzr (ORCPT ); Thu, 31 Jan 2019 11:55:47 -0500 Received: from mail.kernel.org ([198.145.29.99]:55886 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727095AbfAaQzr (ORCPT ); Thu, 31 Jan 2019 11:55:47 -0500 Received: from bbrezillon (91-160-177-164.subs.proxad.net [91.160.177.164]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5EDE2218AF; Thu, 31 Jan 2019 16:55:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548953746; bh=5InK5VVpqOh9e3SQsYJHpCS38H6ABMfXKqzoKGLxjl8=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=WYPSA056mZica1VwG8DG43PAnno1y7GGhDARRwdmhsXCFiuDIwkUHXb/rKr4t1Y5S rMuz1uK6DC1gWjjKzeJYMvgjOQCv7yC4tNWXhUPt0HzXncCzWZ/Kjaq5Ng6xz79y/9 LfE9MVeeEWfA7rQ5SELv1Xt9OeLpXBZ+uvdxG/Sk= Date: Thu, 31 Jan 2019 17:55:35 +0100 From: Boris Brezillon To: Cc: , , , , , , , , , , Subject: Re: [PATCH v2 01/10] spi: atmel-quadspi: cache MR value to avoid a write access Message-ID: <20190131175535.3f60ccff@bbrezillon> In-Reply-To: <20190131161515.21605-2-tudor.ambarus@microchip.com> References: <20190131161515.21605-1-tudor.ambarus@microchip.com> <20190131161515.21605-2-tudor.ambarus@microchip.com> X-Mailer: Claws Mail 3.16.0 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 31 Jan 2019 16:15:28 +0000 wrote: > From: Tudor Ambarus > > Cache MR value to avoid write access when setting the controller > in Serial Memory Mode (SMM). SMM is set in exec_op() and not at > probe time, to let room for future regular SPI support. > > Signed-off-by: Tudor Ambarus > --- > v2: cache MR value instead of moving the write access at probe > > drivers/spi/atmel-quadspi.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/spi/atmel-quadspi.c b/drivers/spi/atmel-quadspi.c > index ddc712410812..fe05aee5d845 100644 > --- a/drivers/spi/atmel-quadspi.c > +++ b/drivers/spi/atmel-quadspi.c > @@ -155,6 +155,7 @@ struct atmel_qspi { > struct clk *clk; > struct platform_device *pdev; > u32 pending; > + u32 mr; > struct completion cmd_completion; > }; > > @@ -238,7 +239,9 @@ static int atmel_qspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op) > icr = QSPI_ICR_INST(op->cmd.opcode); > ifr = QSPI_IFR_INSTEN; > > - qspi_writel(aq, QSPI_MR, QSPI_MR_SMM); > + /* Set the QSPI controller in Serial Memory Mode */ > + if (!(aq->mr & QSPI_MR_SMM)) if (aq->mr != QSPI_MR_SMM) > + qspi_writel(aq, QSPI_MR, QSPI_MR_SMM); You need to update ->mr here. > > mode = find_mode(op); > if (mode < 0)