Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752729AbaLPAoP (ORCPT ); Mon, 15 Dec 2014 19:44:15 -0500 Received: from c-82-192-226-27.customer.ggaweb.ch ([82.192.226.27]:33668 "EHLO dizzy-6.o2s.ch" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752664AbaLPAoJ (ORCPT ); Mon, 15 Dec 2014 19:44:09 -0500 Subject: [PATCH 3/4] mmc: sunxi: Reset behavior fix From: David =?utf-8?q?Lanzend=C3=B6rfer?= To: Ulf Hansson , Tomeu Vizoso , Arnd Bergmann , linux-mmc@vger.kernel.org, Chris Ball , linux-kernel@vger.kernel.org, Peter Griffin , Hans de Goede , Chen-Yu Tsai , David =?utf-8?q?Lanzend=C3=B6rfer?= , =?utf-8?b?5p2O5oOz?= , Maxime Ripard , linux-arm-kernel@lists.infradead.org Date: Tue, 16 Dec 2014 01:37:56 +0100 Message-ID: <20141216003756.15488.34861.stgit@dizzy-6.o2s.ch> In-Reply-To: <20141216003412.15488.54812.stgit@dizzy-6.o2s.ch> References: <20141216003412.15488.54812.stgit@dizzy-6.o2s.ch> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When there is only one DES available the DMA performs a FIFO reset and waits until the reinitialization has been completed. Disabling the SDXC_IDMAC_DES0_DIC bit prevents the DMA from sending an interrupt after it has finished this reinitialization. The flags SDXC_IDMAC_DES0_FD and SDXC_IDMAC_DES0_LD are both required in order to use the controller with more than one DES. Signed-off-by: David Lanzendörfer Reported-by: 李想 --- drivers/mmc/host/sunxi-mmc.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c index 50bd3d2..5331c88 100644 --- a/drivers/mmc/host/sunxi-mmc.c +++ b/drivers/mmc/host/sunxi-mmc.c @@ -310,7 +310,17 @@ static void sunxi_mmc_init_idma_des(struct sunxi_mmc_host *host, } pdes[0].config |= SDXC_IDMAC_DES0_FD; - pdes[i - 1].config = SDXC_IDMAC_DES0_OWN | SDXC_IDMAC_DES0_LD; + + /* + * When there is only one DES available the DMA performs a FIFO reset and waits + * until the reinitialization has been completed. + * Disabling the SDXC_IDMAC_DES0_DIC bit prevents the DMA from sending an interrupt + * after it has finished this reinitialization. + */ + pdes[i - 1].config = SDXC_IDMAC_DES0_OWN; + pdes[i - 1].config |= SDXC_IDMAC_DES0_FD; + pdes[i - 1].config |= SDXC_IDMAC_DES0_LD; + pdes[i - 1].config &= ~SDXC_IDMAC_DES0_DIC; /* * Avoid the io-store starting the idmac hitting io-mem before the -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/