From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751625AbaKQIkn (ORCPT ); Mon, 17 Nov 2014 03:40:43 -0500 Received: from mga14.intel.com ([192.55.52.115]:60498 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751090AbaKQIkm (ORCPT ); Mon, 17 Nov 2014 03:40:42 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,862,1389772800"; d="scan'208";a="417498481" From: Jani Nikula To: Nicholas Krause , airlied@linux.ie Cc: airlied@redhat.com, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org Subject: Re: [PATCH] drivers: Change calls to mdelay to msleep in order to stop CPU busy looping in mdfld_dsi_pkg_sender.c In-Reply-To: <1416075673-23281-1-git-send-email-xerofoify@gmail.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <1416075673-23281-1-git-send-email-xerofoify@gmail.com> User-Agent: Notmuch/0.19~rc1+1~g08b4944 (http://notmuchmail.org) Emacs/24.4.1 (x86_64-pc-linux-gnu) Date: Mon, 17 Nov 2014 10:40:43 +0200 Message-ID: <87ioieusms.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 15 Nov 2014, Nicholas Krause wrote: > Changes the calls of mdelay to msleep in the driver file mdfld_dsi_pkg_sender.c > in order to prevent CPU busy looping in order to save CPU cycles as this is > considered bad form over sleeping the CPU for high resolution timer function > calls as this driver needs in order to function properly. The code paths are called with sender->lock spinlock held. BR, Jani. > > Signed-off-by: Nicholas Krause > --- > drivers/gpu/drm/gma500/mdfld_dsi_pkg_sender.c | 15 +++++---------- > 1 file changed, 5 insertions(+), 10 deletions(-) > > diff --git a/drivers/gpu/drm/gma500/mdfld_dsi_pkg_sender.c b/drivers/gpu/drm/gma500/mdfld_dsi_pkg_sender.c > index 87885d8..77c656a 100644 > --- a/drivers/gpu/drm/gma500/mdfld_dsi_pkg_sender.c > +++ b/drivers/gpu/drm/gma500/mdfld_dsi_pkg_sender.c > @@ -335,13 +335,11 @@ static int send_pkg_prepare(struct mdfld_dsi_pkg_sender *sender, u8 data_type, > > /*wait for 120 milliseconds in case exit_sleep_mode just be sent*/ > if (unlikely(cmd == DCS_ENTER_SLEEP_MODE)) { > - /*TODO: replace it with msleep later*/ > - mdelay(120); > + msleep(120); > } > > if (unlikely(cmd == DCS_EXIT_SLEEP_MODE)) { > - /*TODO: replace it with msleep later*/ > - mdelay(120); > + msleep(120); > } > return 0; > } > @@ -364,15 +362,12 @@ static int send_pkg_done(struct mdfld_dsi_pkg_sender *sender, u8 data_type, > /*update panel status*/ > if (unlikely(cmd == DCS_ENTER_SLEEP_MODE)) { > sender->panel_mode |= MDFLD_DSI_PANEL_MODE_SLEEP; > - /*TODO: replace it with msleep later*/ > - mdelay(120); > + msleep(120); > } else if (unlikely(cmd == DCS_EXIT_SLEEP_MODE)) { > sender->panel_mode &= ~MDFLD_DSI_PANEL_MODE_SLEEP; > - /*TODO: replace it with msleep later*/ > - mdelay(120); > + msleep(120); > } else if (unlikely(cmd == DCS_SOFT_RESET)) { > - /*TODO: replace it with msleep later*/ > - mdelay(5); > + msleep(5); > } > > sender->status = MDFLD_DSI_PKG_SENDER_FREE; > -- > 1.9.1 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/dri-devel -- Jani Nikula, Intel Open Source Technology Center