From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752554AbdF3MOk (ORCPT ); Fri, 30 Jun 2017 08:14:40 -0400 Received: from metis.ext.4.pengutronix.de ([92.198.50.35]:55749 "EHLO metis.ext.4.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752495AbdF3MOi (ORCPT ); Fri, 30 Jun 2017 08:14:38 -0400 Date: Fri, 30 Jun 2017 14:14:33 +0200 From: Sascha Hauer To: Mark Brown Cc: Jiada Wang , festevam@gmail.com, linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: Applied "spi: imx: dynamic burst length adjust for PIO mode" to the spi tree Message-ID: <20170630121433.piznjqtmhy35zty6@pengutronix.de> References: <20170613083402.22324-1-jiada_wang@mentor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Sent-From: Pengutronix Hildesheim X-URL: http://www.pengutronix.de/ X-IRC: #ptxdist @freenode X-Accept-Language: de,en X-Accept-Content-Type: text/plain X-Uptime: 14:08:22 up 20 days, 4:18, 33 users, load average: 0.01, 0.06, 0.04 User-Agent: Mutt/1.6.2-neo (2016-06-11) X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::c0 X-SA-Exim-Mail-From: sha@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Mark, On Fri, Jun 30, 2017 at 01:00:22PM +0100, Mark Brown wrote: > The patch > > spi: imx: dynamic burst length adjust for PIO mode > > has been applied to the spi tree at > > git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git Argh, I wasn't fast enough. I just ran spi-loopback-test.ko with this patch and it doesn't work properly. > + if (spi_imx->count == spi_imx->remainder) { > + ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL); > + ctrl &= ~MX51_ECSPI_CTRL_BL_MASK; > + if (spi_imx->count > MX51_ECSPI_CTRL_MAX_BURST) { > + spi_imx->remainder = spi_imx->count % > + MX51_ECSPI_CTRL_MAX_BURST; > + val = MX51_ECSPI_CTRL_MAX_BURST; This is wrong. MX51_ECSPI_CTRL_MAX_BURST contains the burst length in bytes, but the register 'val' is written to takes the burst length in bits - 1, so this should be: val = MX51_ECSPI_CTRL_MAX_BURST * 8 - 1; instead. Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |