Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754177AbaJCWIu (ORCPT ); Fri, 3 Oct 2014 18:08:50 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:46643 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932423AbaJCWGH (ORCPT ); Fri, 3 Oct 2014 18:06:07 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, John Stultz , Peter Maydell , Russell King , Kees Cook , Ulf Hansson Subject: [PATCH 3.16 342/357] mmc: mmci: Reverse IRQ handling for the arm_variant Date: Fri, 3 Oct 2014 14:32:08 -0700 Message-Id: <20141003212943.727897468@linuxfoundation.org> X-Mailer: git-send-email 2.1.2 In-Reply-To: <20141003212933.458851516@linuxfoundation.org> References: <20141003212933.458851516@linuxfoundation.org> User-Agent: quilt/0.63-1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ulf Hansson commit 7878289b269d41c8e611aa6d4519feae706e49f3 upstream. Commit "mmc: mmci: Handle CMD irq before DATA irq", caused an issue when using the ARM model of the PL181 and running QEMU. The bug was reported for the following QEMU version: $ qemu-system-arm -version QEMU emulator version 2.0.0 (Debian 2.0.0+dfsg-2ubuntu1.1), Copyright (c) 2003-2008 Fabrice Bellard To resolve the problem, let's restore the old behavior were the DATA irq is handled prior the CMD irq, but only for the arm_variant, which the problem was reported for. Reported-by: John Stultz Cc: Peter Maydell Cc: Russell King Tested-by: Kees Cook Tested-by: John Stultz Cc: # v3.15+ Signed-off-by: Ulf Hansson [kees: backported to 3.16] Signed-off-by: Kees Cook Signed-off-by: Greg Kroah-Hartman --- drivers/mmc/host/mmci.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) --- a/drivers/mmc/host/mmci.c +++ b/drivers/mmc/host/mmci.c @@ -65,6 +65,7 @@ static unsigned int fmax = 515633; * @pwrreg_clkgate: MMCIPOWER register must be used to gate the clock * @busy_detect: true if busy detection on dat0 is supported * @pwrreg_nopower: bits in MMCIPOWER don't controls ext. power supply + * @reversed_irq_handling: handle data irq before cmd irq. */ struct variant_data { unsigned int clkreg; @@ -80,6 +81,7 @@ struct variant_data { bool pwrreg_clkgate; bool busy_detect; bool pwrreg_nopower; + bool reversed_irq_handling; }; static struct variant_data variant_arm = { @@ -87,6 +89,7 @@ static struct variant_data variant_arm = .fifohalfsize = 8 * 4, .datalength_bits = 16, .pwrreg_powerup = MCI_PWR_UP, + .reversed_irq_handling = true, }; static struct variant_data variant_arm_extended_fifo = { @@ -1163,8 +1166,13 @@ static irqreturn_t mmci_irq(int irq, voi dev_dbg(mmc_dev(host->mmc), "irq0 (data+cmd) %08x\n", status); - mmci_cmd_irq(host, host->cmd, status); - mmci_data_irq(host, host->data, status); + if (host->variant->reversed_irq_handling) { + mmci_data_irq(host, host->data, status); + mmci_cmd_irq(host, host->cmd, status); + } else { + mmci_cmd_irq(host, host->cmd, status); + mmci_data_irq(host, host->data, status); + } /* Don't poll for busy completion in irq context. */ if (host->busy_status) -- 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/