From patchwork Fri Oct 1 11:04:55 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Ujfalusi X-Patchwork-Id: 223222 X-Patchwork-Delegate: tony@atomide.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id o91B4wO5006849 for ; Fri, 1 Oct 2010 11:04:59 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754898Ab0JALE5 (ORCPT ); Fri, 1 Oct 2010 07:04:57 -0400 Received: from smtp.nokia.com ([147.243.1.47]:22879 "EHLO mgw-sa01.nokia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754125Ab0JALE4 (ORCPT ); Fri, 1 Oct 2010 07:04:56 -0400 Received: from cseresznye.nmp.nokia.com (cseresznye.nmp.nokia.com [172.22.211.20]) by mgw-sa01.nokia.com (Switch-3.4.3/Switch-3.4.3) with ESMTP id o91B4orB016435; Fri, 1 Oct 2010 14:04:51 +0300 From: Peter Ujfalusi To: Tony Lindgren Cc: linux-omap@vger.kernel.org, Jarkko Nikula , Liam Girdwood , Nishanth Menon Subject: [PATCH v2 2/2] OMAP3: DMA: Errata: sDMA FIFO draining does not finish Date: Fri, 1 Oct 2010 14:04:55 +0300 Message-Id: <1285931095-21053-3-git-send-email-peter.ujfalusi@nokia.com> X-Mailer: git-send-email 1.7.3 In-Reply-To: <1285931095-21053-1-git-send-email-peter.ujfalusi@nokia.com> References: <1285931095-21053-1-git-send-email-peter.ujfalusi@nokia.com> X-Nokia-AV: Clean Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter1.kernel.org [140.211.167.41]); Fri, 01 Oct 2010 11:04:59 +0000 (UTC) diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c index 7115884..287a00e 100644 --- a/arch/arm/plat-omap/dma.c +++ b/arch/arm/plat-omap/dma.c @@ -30,6 +30,7 @@ #include #include #include +#include #include #include @@ -1018,8 +1019,38 @@ void omap_stop_dma(int lch) dma_write(0, CICR(lch)); l = dma_read(CCR(lch)); - l &= ~OMAP_DMA_CCR_EN; - dma_write(l, CCR(lch)); + /* OMAP3 Errata i541: sDMA FIFO draining does not finish */ + if (cpu_is_omap34xx() && (l & OMAP_DMA_CCR_SEL_SRC_DST_SYNC)) { + int i = 0; + u32 sys_cf; + + /* Configure No-Standby */ + l = sys_cf = dma_read(OCP_SYSCONFIG); + l &= ~DMA_SYSCONFIG_MIDLEMODE_MASK; + l |= DMA_SYSCONFIG_MIDLEMODE(DMA_IDLEMODE_NO_IDLE); + dma_write(l , OCP_SYSCONFIG); + + l = dma_read(CCR(lch)); + l &= ~OMAP_DMA_CCR_EN; + dma_write(l, CCR(lch)); + + /* Wait for sDMA FIFO drain */ + l = dma_read(CCR(lch)); + while (i < 100 && (l & (OMAP_DMA_CCR_RD_ACTIVE | + OMAP_DMA_CCR_WR_ACTIVE))) { + udelay(5); + i++; + l = dma_read(CCR(lch)); + } + if (i >= 100) + printk(KERN_ERR "DMA drain did not completed on " + "lch %d\n", lch); + /* Restore OCP_SYSCONFIG */ + dma_write(sys_cf, OCP_SYSCONFIG); + } else { + l &= ~OMAP_DMA_CCR_EN; + dma_write(l, CCR(lch)); + } if (!omap_dma_in_1510_mode() && dma_chan[lch].next_lch != -1) { int next_lch, cur_lch = lch; diff --git a/arch/arm/plat-omap/include/plat/dma.h b/arch/arm/plat-omap/include/plat/dma.h index 776ba44..cf66f85 100644 --- a/arch/arm/plat-omap/include/plat/dma.h +++ b/arch/arm/plat-omap/include/plat/dma.h @@ -335,6 +335,9 @@ #define OMAP2_DMA_MISALIGNED_ERR_IRQ (1 << 11) #define OMAP_DMA_CCR_EN (1 << 7) +#define OMAP_DMA_CCR_RD_ACTIVE (1 << 9) +#define OMAP_DMA_CCR_WR_ACTIVE (1 << 10) +#define OMAP_DMA_CCR_SEL_SRC_DST_SYNC (1 << 24) #define OMAP_DMA_CCR_BUFFERING_DISABLE (1 << 25) #define OMAP_DMA_DATA_TYPE_S8 0x00