From mboxrd@z Thu Jan 1 00:00:00 1970 From: "G, Manjunath Kondaiah" Subject: [PATCH v4 4/4] OMAP: DMA: Fix: context restore during off mode Date: Mon, 28 Mar 2011 19:57:02 +0530 Message-ID: <1301322422-29886-5-git-send-email-manjugk@ti.com> References: <1301322422-29886-1-git-send-email-manjugk@ti.com> Return-path: Received: from comal.ext.ti.com ([198.47.26.152]:55909 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754082Ab1C1OcG (ORCPT ); Mon, 28 Mar 2011 10:32:06 -0400 In-Reply-To: <1301322422-29886-1-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.infradead.org Cc: khilman@ti.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 | 9 --------- 1 files changed, 0 insertions(+), 9 deletions(-) diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c index 3c39794..5c4ae7d 100644 --- a/arch/arm/plat-omap/dma.c +++ b/arch/arm/plat-omap/dma.c @@ -2059,29 +2059,20 @@ 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); } void omap_dma_global_context_restore(void) { - int ch; - 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 From mboxrd@z Thu Jan 1 00:00:00 1970 From: manjugk@ti.com (G, Manjunath Kondaiah) Date: Mon, 28 Mar 2011 19:57:02 +0530 Subject: [PATCH v4 4/4] OMAP: DMA: Fix: context restore during off mode In-Reply-To: <1301322422-29886-1-git-send-email-manjugk@ti.com> References: <1301322422-29886-1-git-send-email-manjugk@ti.com> Message-ID: <1301322422-29886-5-git-send-email-manjugk@ti.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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 | 9 --------- 1 files changed, 0 insertions(+), 9 deletions(-) diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c index 3c39794..5c4ae7d 100644 --- a/arch/arm/plat-omap/dma.c +++ b/arch/arm/plat-omap/dma.c @@ -2059,29 +2059,20 @@ 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); } void omap_dma_global_context_restore(void) { - int ch; - 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