From patchwork Fri Oct 4 10:44:06 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Markus Pargmann X-Patchwork-Id: 2988021 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 36D599F245 for ; Fri, 4 Oct 2013 10:46:16 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id F29ED2012C for ; Fri, 4 Oct 2013 10:46:14 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 7183C20122 for ; Fri, 4 Oct 2013 10:46:13 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VS2sr-0000cI-GG; Fri, 04 Oct 2013 10:45:21 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1VS2sc-00081C-JP; Fri, 04 Oct 2013 10:45:06 +0000 Received: from metis.ext.pengutronix.de ([2001:6f8:1178:4:290:27ff:fe1d:cc33]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VS2sP-0007xw-EC for linux-arm-kernel@lists.infradead.org; Fri, 04 Oct 2013 10:44:55 +0000 Received: from dude.hi.pengutronix.de ([2001:6f8:1178:2:21e:67ff:fe11:9c5c]) by metis.ext.pengutronix.de with esmtp (Exim 4.72) (envelope-from ) id 1VS2rq-0006XE-33; Fri, 04 Oct 2013 12:44:18 +0200 Received: from mpa by dude.hi.pengutronix.de with local (Exim 4.80) (envelope-from ) id 1VS2ro-00039n-C3; Fri, 04 Oct 2013 12:44:16 +0200 From: Markus Pargmann To: Vinod Koul Subject: [PATCH v3 1/4] dma: mxs-dma: Cleanup interrupt handler Date: Fri, 4 Oct 2013 12:44:06 +0200 Message-Id: <1380883449-8649-2-git-send-email-mpa@pengutronix.de> X-Mailer: git-send-email 1.8.4.rc3 In-Reply-To: <1380883449-8649-1-git-send-email-mpa@pengutronix.de> References: <1380883449-8649-1-git-send-email-mpa@pengutronix.de> X-SA-Exim-Connect-IP: 2001:6f8:1178:2:21e:67ff:fe11:9c5c X-SA-Exim-Mail-From: mpa@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-arm-kernel@lists.infradead.org X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20131004_064453_883241_126C1A28 X-CRM114-Status: GOOD ( 21.20 ) X-Spam-Score: -2.6 (--) Cc: Markus Pargmann , kernel@pengutronix.de, linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The DMA interrupt handler uses its controll registers to handle all available channel interrupts it can find. This patch changes it to handle only one interrupt by directly mapping irq number to channel. It also includes a cleanup of the ctrl-register usage. Signed-off-by: Markus Pargmann --- drivers/dma/mxs-dma.c | 96 ++++++++++++++++++++++++++++++++------------------- 1 file changed, 60 insertions(+), 36 deletions(-) diff --git a/drivers/dma/mxs-dma.c b/drivers/dma/mxs-dma.c index ccd13df..13198e5 100644 --- a/drivers/dma/mxs-dma.c +++ b/drivers/dma/mxs-dma.c @@ -27,6 +27,7 @@ #include #include #include +#include #include @@ -272,58 +273,81 @@ static void mxs_dma_tasklet(unsigned long data) mxs_chan->desc.callback(mxs_chan->desc.callback_param); } +static int mxs_dma_irq_to_chan(struct mxs_dma_engine *mxs_dma, int irq) +{ + int i; + + for (i = 0; i != mxs_dma->nr_channels; ++i) + if (mxs_dma->mxs_chans[i].chan_irq == irq) + return i; + + return -EINVAL; +} + static irqreturn_t mxs_dma_int_handler(int irq, void *dev_id) { struct mxs_dma_engine *mxs_dma = dev_id; - u32 stat1, stat2; + struct mxs_dma_chan *mxs_chan; + u32 completed; + u32 err; + int chan = mxs_dma_irq_to_chan(mxs_dma, irq); + + if (chan < 0) + return IRQ_NONE; /* completion status */ - stat1 = readl(mxs_dma->base + HW_APBHX_CTRL1); - stat1 &= MXS_DMA_CHANNELS_MASK; - writel(stat1, mxs_dma->base + HW_APBHX_CTRL1 + STMP_OFFSET_REG_CLR); + completed = readl(mxs_dma->base + HW_APBHX_CTRL1); + completed = (completed >> chan) & 0x1; + + /* Clear interrupt */ + writel((1 << chan), + mxs_dma->base + HW_APBHX_CTRL1 + STMP_OFFSET_REG_CLR); /* error status */ - stat2 = readl(mxs_dma->base + HW_APBHX_CTRL2); - writel(stat2, mxs_dma->base + HW_APBHX_CTRL2 + STMP_OFFSET_REG_CLR); + err = readl(mxs_dma->base + HW_APBHX_CTRL2); + err &= (1 << (MXS_DMA_CHANNELS + chan)) | (1 << chan); + + /* + * error status bit is in the upper 16 bits, error irq bit in the lower + * 16 bits. We transform it into a simpler error code: + * err: 0x00 = no error, 0x01 = TERMINATION, 0x02 = BUS_ERROR + */ + err = (err >> (MXS_DMA_CHANNELS + chan)) + (err >> chan); + + /* Clear error irq */ + writel((1 << chan), + mxs_dma->base + HW_APBHX_CTRL2 + STMP_OFFSET_REG_CLR); /* * When both completion and error of termination bits set at the * same time, we do not take it as an error. IOW, it only becomes - * an error we need to handle here in case of either it's (1) a bus - * error or (2) a termination error with no completion. + * an error we need to handle here in case of either it's a bus + * error or a termination error with no completion. 0x01 is termination + * error, so we can subtract err & completed to get the real error case. */ - stat2 = ((stat2 >> MXS_DMA_CHANNELS) & stat2) | /* (1) */ - (~(stat2 >> MXS_DMA_CHANNELS) & stat2 & ~stat1); /* (2) */ - - /* combine error and completion status for checking */ - stat1 = (stat2 << MXS_DMA_CHANNELS) | stat1; - while (stat1) { - int channel = fls(stat1) - 1; - struct mxs_dma_chan *mxs_chan = - &mxs_dma->mxs_chans[channel % MXS_DMA_CHANNELS]; - - if (channel >= MXS_DMA_CHANNELS) { - dev_dbg(mxs_dma->dma_device.dev, - "%s: error in channel %d\n", __func__, - channel - MXS_DMA_CHANNELS); - mxs_chan->status = DMA_ERROR; - mxs_dma_reset_chan(mxs_chan); - } else { - if (mxs_chan->flags & MXS_DMA_SG_LOOP) - mxs_chan->status = DMA_IN_PROGRESS; - else - mxs_chan->status = DMA_SUCCESS; - } + err -= err & completed; - stat1 &= ~(1 << channel); + mxs_chan = &mxs_dma->mxs_chans[chan]; - if (mxs_chan->status == DMA_SUCCESS) - dma_cookie_complete(&mxs_chan->desc); - - /* schedule tasklet on this channel */ - tasklet_schedule(&mxs_chan->tasklet); + if (err) { + dev_dbg(mxs_dma->dma_device.dev, + "%s: error in channel %d\n", __func__, + chan); + mxs_chan->status = DMA_ERROR; + mxs_dma_reset_chan(mxs_chan); + } else { + if (mxs_chan->flags & MXS_DMA_SG_LOOP) + mxs_chan->status = DMA_IN_PROGRESS; + else + mxs_chan->status = DMA_SUCCESS; } + if (mxs_chan->status == DMA_SUCCESS) + dma_cookie_complete(&mxs_chan->desc); + + /* schedule tasklet on this channel */ + tasklet_schedule(&mxs_chan->tasklet); + return IRQ_HANDLED; }