From patchwork Thu Jul 30 07:46:31 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kishon Vijay Abraham I X-Patchwork-Id: 6899581 Return-Path: X-Original-To: patchwork-linux-mmc@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 3F040C05AC for ; Thu, 30 Jul 2015 07:49:22 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 614D820511 for ; Thu, 30 Jul 2015 07:49:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0D2C32051C for ; Thu, 30 Jul 2015 07:49:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754600AbbG3Hri (ORCPT ); Thu, 30 Jul 2015 03:47:38 -0400 Received: from bear.ext.ti.com ([192.94.94.41]:50424 "EHLO bear.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751577AbbG3Hrg (ORCPT ); Thu, 30 Jul 2015 03:47:36 -0400 Received: from dflxv15.itg.ti.com ([128.247.5.124]) by bear.ext.ti.com (8.13.7/8.13.7) with ESMTP id t6U7l5sF013420; Thu, 30 Jul 2015 02:47:05 -0500 Received: from DFLE72.ent.ti.com (dfle72.ent.ti.com [128.247.5.109]) by dflxv15.itg.ti.com (8.14.3/8.13.8) with ESMTP id t6U7l5vV010353; Thu, 30 Jul 2015 02:47:05 -0500 Received: from dlep32.itg.ti.com (157.170.170.100) by DFLE72.ent.ti.com (128.247.5.109) with Microsoft SMTP Server id 14.3.224.2; Thu, 30 Jul 2015 02:47:05 -0500 Received: from a0393678ub.india.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by dlep32.itg.ti.com (8.14.3/8.13.8) with ESMTP id t6U7kZVc006418; Thu, 30 Jul 2015 02:47:02 -0500 From: Kishon Vijay Abraham I To: , , , , , , CC: , , Subject: [PATCH 08/11] mmc: host: omap_hsmmc: Workaround for errata id i802 Date: Thu, 30 Jul 2015 13:16:31 +0530 Message-ID: <1438242394-25599-9-git-send-email-kishon@ti.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1438242394-25599-1-git-send-email-kishon@ti.com> References: <1438242394-25599-1-git-send-email-kishon@ti.com> MIME-Version: 1.0 Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org X-Spam-Status: No, score=-8.3 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, 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 According to errata i802, DCRC error interrupts (MMCHS_STAT[21] DCRC=0x1) can occur during the tuning procedure. The DCRC interrupt, occurs when the last tuning block fails (the last ratio tested). The delay from CRC check until the interrupt is asserted is bigger than the delay until assertion of the tuning end flag. Assertion of tuning end flag is what masks the interrupts. Because of this race, an erroneous DCRC interrupt occurs. The suggested workaround is to disable DCRC interrupts during the tuning procedure which is implemented here. Signed-off-by: Kishon Vijay Abraham I Signed-off-by: Sekhar Nori --- drivers/mmc/host/omap_hsmmc.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c index dcfa92e..96dd406 100644 --- a/drivers/mmc/host/omap_hsmmc.c +++ b/drivers/mmc/host/omap_hsmmc.c @@ -656,8 +656,17 @@ static void omap_hsmmc_enable_irq(struct omap_hsmmc_host *host, is_tuning = (cmd->opcode == MMC_SEND_TUNING_BLOCK) || (cmd->opcode == MMC_SEND_TUNING_BLOCK_HS200); - if (!is_tuning && host->use_dma) + if (is_tuning) { + /* + * OMAP5/DRA74X/DRA72x Errata i802: + * DCRC error interrupts (MMCHS_STAT[21] DCRC=0x1) can occur + * during the tuning procedure. So disable it during the + * tuning procedure. + */ + irq_mask &= ~DCRC_EN; + } else if (host->use_dma) { irq_mask &= ~(BRR_EN | BWR_EN); + } /* Disable timeout for erases */ if (cmd->opcode == MMC_ERASE)