From patchwork Fri Apr 5 07:40:51 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adrian Hunter X-Patchwork-Id: 2397061 Return-Path: X-Original-To: patchwork-linux-mmc@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id 6B36ADF2E5 for ; Fri, 5 Apr 2013 07:35:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161302Ab3DEHf3 (ORCPT ); Fri, 5 Apr 2013 03:35:29 -0400 Received: from mga02.intel.com ([134.134.136.20]:39078 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752174Ab3DEHf3 (ORCPT ); Fri, 5 Apr 2013 03:35:29 -0400 Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga101.jf.intel.com with ESMTP; 05 Apr 2013 00:35:28 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.87,413,1363158000"; d="scan'208";a="289773816" Received: from ahunter-desktop.fi.intel.com (HELO [10.237.72.194]) ([10.237.72.194]) by orsmga001.jf.intel.com with ESMTP; 05 Apr 2013 00:35:26 -0700 Message-ID: <515E8003.1060002@intel.com> Date: Fri, 05 Apr 2013 10:40:51 +0300 From: Adrian Hunter Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130110 Thunderbird/17.0.2 MIME-Version: 1.0 To: Chris Ball CC: Adrian Hunter , Ulf Hansson , linux-mmc@vger.kernel.org, Linus Walleij , Namjae Jeon , Sergey Yanovich , Jaehoon Chung , Mark Brown Subject: [PATCH V2 2/2] mmc: core: fix performance regression initializing MMC, host controllers References: <1365082866-28404-1-git-send-email-adrian.hunter@intel.com> <1365082866-28404-3-git-send-email-adrian.hunter@intel.com> <515E7CB2.9020602@intel.com> In-Reply-To: <515E7CB2.9020602@intel.com> Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org Commit fa5501890d8974301042e0202d342a6cbe8609f4 introduced a performance regression by adding mmc_power_up() to mmc_start_host(). mmc_power_up() is not necessary to host controller initialization, it is part of card initialization and is performed anyway asynchronously. Please see the original commit for an explanation of the use of mmc_power_up() in mmc_start_host(). This patch allows a driver to leave the power up in asynchronous code (as it was before). On my current target platform this reduces driver initialization from: [ 1.313220] initcall sdhci_acpi_driver_init+0x0/0x12 returned 0 after 102008 usecs to this: [ 1.217209] initcall sdhci_acpi_driver_init+0x0/0x12 returned 0 after 8331 usecs Signed-off-by: Adrian Hunter --- drivers/mmc/core/core.c | 3 ++- drivers/mmc/host/sdhci-acpi.c | 2 ++ include/linux/mmc/host.h | 1 + 3 files changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index 3bf1c46..c1893c9 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -2416,7 +2416,8 @@ void mmc_start_host(struct mmc_host *host) { host->f_init = max(freqs[0], host->f_min); host->rescan_disable = 0; - mmc_power_up(host); + if (!(host->caps2 & MMC_CAP2_NO_PRESCAN_POWERUP)) + mmc_power_up(host); mmc_detect_change(host, 0); } diff --git a/drivers/mmc/host/sdhci-acpi.c b/drivers/mmc/host/sdhci-acpi.c index 2592ddd..7bcf74b 100644 --- a/drivers/mmc/host/sdhci-acpi.c +++ b/drivers/mmc/host/sdhci-acpi.c @@ -195,6 +195,8 @@ static int sdhci_acpi_probe(struct platform_device *pdev) host->mmc->pm_caps |= c->slot->pm_caps; } + host->mmc->caps2 |= MMC_CAP2_NO_PRESCAN_POWERUP; + err = sdhci_add_host(host); if (err) goto err_free; diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index 17d7148..8873e83 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -280,6 +280,7 @@ struct mmc_host { #define MMC_CAP2_PACKED_WR (1 << 13) /* Allow packed write */ #define MMC_CAP2_PACKED_CMD (MMC_CAP2_PACKED_RD | \ MMC_CAP2_PACKED_WR) +#define MMC_CAP2_NO_PRESCAN_POWERUP (1 << 14) /* Don't power up before scan */ mmc_pm_flag_t pm_caps; /* supported pm features */