From mboxrd@z Thu Jan 1 00:00:00 1970 From: "G, Manjunath Kondaiah" Subject: [PATCH v2 4/4] OMAP: DMA: Fix: context restore during off mode Date: Fri, 11 Mar 2011 19:50:15 +0530 Message-ID: <1299853215-8507-5-git-send-email-manjugk@ti.com> References: <1299853215-8507-1-git-send-email-manjugk@ti.com> Return-path: Received: from arroyo.ext.ti.com ([192.94.94.40]:43832 "EHLO arroyo.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753224Ab1CKOWT (ORCPT ); Fri, 11 Mar 2011 09:22:19 -0500 In-Reply-To: <1299853215-8507-1-git-send-email-manjugk@ti.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: linux-omap@vger.kernel.org, linux-arm-kernel@lists.arm.linux.org.uk Cc: khilman@deeprootsystems.com, paul@pwsan.com, tony@atomide.com The current DMA context restore clears all the DMA channel registers even if the channels are in use. This will result in transfer failures if repeated DMA transfers are initiated with one time DMA channel configuration. Also, remove access to sysconfig register during context save/restore since it will be handled through hwmod layer. Tested on OMAP3430 Zoom2 with - off mode enabled - one time DMA channel configuration - repeated DMA transfers Signed-off-by: G, Manjunath Kondaiah --- arch/arm/plat-omap/dma.c | 7 ------- 1 files changed, 0 insertions(+), 7 deletions(-) diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c index 5cca56b..bb0b7e2 100644 --- a/arch/arm/plat-omap/dma.c +++ b/arch/arm/plat-omap/dma.c @@ -2059,8 +2059,6 @@ void omap_dma_global_context_save(void) pm_runtime_get_sync(dev); omap_dma_global_context.dma_irqenable_l0 = p->dma_read(IRQENABLE_L0, 0); - omap_dma_global_context.dma_ocp_sysconfig = - p->dma_read(OCP_SYSCONFIG, 0); omap_dma_global_context.dma_gcr = p->dma_read(GCR, 0); pm_runtime_put_autosuspend(dev); } @@ -2071,17 +2069,12 @@ void omap_dma_global_context_restore(void) pm_runtime_get_sync(dev); p->dma_write(omap_dma_global_context.dma_gcr, GCR, 0); - p->dma_write(omap_dma_global_context.dma_ocp_sysconfig, - OCP_SYSCONFIG, 0); p->dma_write(omap_dma_global_context.dma_irqenable_l0, IRQENABLE_L0, 0); if (IS_DMA_ERRATA(DMA_ROMCODE_BUG)) p->dma_write(0x3 , IRQSTATUS_L0, 0); - for (ch = 0; ch < dma_chan_count; ch++) - if (dma_chan[ch].dev_id != -1) - omap_clear_dma(ch); pm_runtime_put_autosuspend(dev); } -- 1.7.1