Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752409Ab3HUH3p (ORCPT ); Wed, 21 Aug 2013 03:29:45 -0400 Received: from mail-ea0-f171.google.com ([209.85.215.171]:61410 "EHLO mail-ea0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752246Ab3HUH3o (ORCPT ); Wed, 21 Aug 2013 03:29:44 -0400 Date: Wed, 21 Aug 2013 09:29:40 +0200 From: Ingo Molnar To: Li Fei Cc: hpa@zytor.com, mingo@redhat.com, tglx@linutronix.de, chuansheng.liu@intel.com, x86@kernel.org, akpm@linux-foundation.org, holt@sgi.com, rmk+kernel@arm.linux.org.uk, linux-kernel@vger.kernel.org Subject: Re: [PATCH] reboot: perform warm/cold reset correctly for CF9 type Message-ID: <20130821072940.GB27495@gmail.com> References: <1377049949.18357.3.camel@fli24-HP-Compaq-8100-Elite-CMT-PC> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1377049949.18357.3.camel@fli24-HP-Compaq-8100-Elite-CMT-PC> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1700 Lines: 52 * Li Fei wrote: > In current implementation for reboot type CF9 and CF9_COND, > warm and cold reset are not differentiated, and both are > performed by writing 0x06 to port 0xCF9 as warm reset. It's not > correct. > > This commit will differentiate warm and cold reset, and perform > them correctly as below: > For warm reset, write 0x06 to port 0xCF9; > For cold reset, write 0x0E to port 0xCF9. > > From: Liu Chuansheng > Signed-off-by: Li Fei > --- > arch/x86/kernel/reboot.c | 9 +++++++-- > 1 files changed, 7 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c > index 563ed91..6e06299 100644 > --- a/arch/x86/kernel/reboot.c > +++ b/arch/x86/kernel/reboot.c > @@ -511,10 +511,15 @@ static void native_machine_emergency_restart(void) > > case BOOT_CF9_COND: > if (port_cf9_safe) { > - u8 cf9 = inb(0xcf9) & ~6; > + u8 cf9 = inb(0xcf9) & > + ~(reboot_mode == REBOOT_WARM ? > + 0x06 : 0x0E); > outb(cf9|2, 0xcf9); /* Request hard reset */ > udelay(50); > - outb(cf9|6, 0xcf9); /* Actually do the reset */ > + /* Actually do the reset */ > + outb(cf9|(reboot_mode == REBOOT_WARM ? > + 0x06 : 0x0E), > + 0xcf9); > udelay(50); Looks good, but please introduce a reboot_val intermediate variable instead of duplicating that ugly line-broken construct twice. Thanks, Ingo -- 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/