From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matt Fleming Subject: Re: efi/reboot: Fall back to original power-off method if EFI_RESET_SHUTDOWN returns Date: Thu, 22 Jun 2017 10:55:17 +0100 Message-ID: <20170622095517.GA3238@codeblueprint.co.uk> References: <20170423123655.13015-1-hdegoede@redhat.com> <430d6ff2-264a-80f8-24e0-0d9af4377844@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-wr0-f169.google.com ([209.85.128.169]:33989 "EHLO mail-wr0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751674AbdFVJzV (ORCPT ); Thu, 22 Jun 2017 05:55:21 -0400 Received: by mail-wr0-f169.google.com with SMTP id 77so16044414wrb.1 for ; Thu, 22 Jun 2017 02:55:20 -0700 (PDT) Content-Disposition: inline In-Reply-To: <430d6ff2-264a-80f8-24e0-0d9af4377844@redhat.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Hans de Goede Cc: Len Brown , Ard Biesheuvel , Andy Shevchenko , linux-acpi@vger.kernel.org, Peter Jones , linux-efi@vger.kernel.org, Mark Salter On Wed, 21 Jun, at 03:15:09PM, Hans de Goede wrote: > HI, > > On 23-04-17 14:36, Hans de Goede wrote: > >Commit 44be28e9dd98 ("x86/reboot: Add EFI reboot quirk for ACPI Hardware > >Reduced flag") sets pm_power_off to efi_power_off() when the > >acpi_gbl_reduced_hardware flag is set. > > > >According to its commit message this is necessary because: "BayTrail-T > >class of hardware requires EFI in order to powerdown and reboot and no > >other reliable method exists" > > > >But I have a Bay Trail CR tablet where the EFI_RESET_SHUTDOWN call does > >not work, it simply returns without doing anything (AFAICT). > > > >So it seems that some Bay Trail devices must use EFI for power-off, while > >for others only ACPI works. > > > >Note that efi_power_off() only gets used if the platform code defines > >efi_poweroff_required() and that returns true, this currently only ever > >happens on x86. > > > >Since on the devices which need ACPI for power-off the EFI_RESET_SHUTDOWN > >call simply returns, this patch makes the efi-reboot code remember the > >old pm_power_off handler and if EFI_RESET_SHUTDOWN returns it falls back > >to calling that. > > > >This seems preferable to dmi-quirking our way out of this, since there > >are likely quite a few devices suffering from this. > > > >Cc: Mark Salter > >Signed-off-by: Hans de Goede > > What is the status of this patch ? It has had 2 somewhat favorable > reviews and then things went silent ? Sorry about the delay. I've picked this up for the efi-next branch since we're at -rc6 and it doesn't look like an -rc6-urgent bug. Thanks!