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2020-10-16ACPI: reboot: Avoid racing after writing to ACPI RESET_REGZhang Rui1-0/+11
According to the ACPI spec, "The system must reset immediately following the write to the ACPI RESET_REG register.", but there are cases that the system does not follow this and results in racing with the subsequetial reboot mechanism, which brings unexpected behavior. Fix this by adding a 15ms delay after writing to the ACPI RESET_REG. Reported-by: Ghorai, Sukumar <sukumar.ghorai@intel.com> Signed-off-by: Zhang Rui <rui.zhang@intel.com> [ rjw: Edit comment in the code and subject ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-12-20ACPI: Allow CONFIG_PCI to be unset for rebootSinan Kaya1-0/+8
Make PCI reboot conditional on CONFIG_PCI set on the kernel configuration. Signed-off-by: Sinan Kaya <okaya@kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-12-20ACPI: Move PCI reset to a separate functionSinan Kaya1-13/+19
Getting ready to factor out PCI specific code when CONFIG_PCI is unset. Create a acpi_pci_reset() that kick starts PCI specific reset. Signed-off-by: Sinan Kaya <okaya@kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-05-02ACPI: add missing newline to printkLaszlo Toth1-2/+2
...and restore reverse xmas tree while at it. Signed-off-by: Laszlo Toth <laszlth@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+1
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-20Revert "ACPI: ignore FADT reset-reg-sup flag"Linus Torvalds1-1/+2
This reverts commit cf450136bfde77c7f95065c91bffded4aa7fa731. It breaks reboot on at least one Thinkpad T43, as reported by Jörg Otte: "On reboot it shuts down as normal. The last lines displayed are: >Unmounting temporary filesystems.. [OK] >Deactivating swap... [OK] >Unmounting local filesystems... [OK] >Will now restart > Restarting system Then I hear it accessing the cd-drive, but then it's being stuck." Jörg bisected the regression to this commit. That commit fixes another machine (see https://bugzilla.kernel.org/show_bug.cgi?id=11533 for details) that has a BIOS bug and doesn't support ACPI reset. However, at least one of those other reporters no longer even has the machine in question, and had a different workaround to begin with. Besides, it clearly was a buggy BIOS. Let's not break the correct case to fix that case. Reported-and-bisected-by: Jörg Otte <jrg.otte@googlemail.com> Cc: linux-acpi@vger.kernel.org Cc: Len Brown <lenb@kernel.org> Cc: Peter Anvin <hpa@zytor.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21ACPI: ignore FADT reset-reg-sup flagLen Brown1-2/+1
we check that the address is non-zero later anyway. https://bugzilla.kernel.org/show_bug.cgi?id=11533 Signed-off-by: Len Brown <len.brown@intel.com>
2011-03-23ACPI: Make sure the FADT is at least rev 2 before using the reset registerMatthew Garrett1-0/+5
The reset register was only introduced with version 2 of the FADT, so we should check that the FADT revision before trusting its contents. Signed-off-by: Matthew Garrett <mjg@redhat.com> Signed-off-by: Len Brown <len.brown@intel.com>
2011-03-23ACPI: Bug compatibility for Windows on the ACPI reboot vectorMatthew Garrett1-5/+4
Windows ignores the bit_offset and bit_width, despite the spec requiring that they be validated. Drop the checks so that we match this behaviour. Windows also goes straight for the keyboard controller if the ACPI reboot fails, so we shouldn't sleep if we're still alive. Signed-off-by: Matthew Garrett <mjg@redhat.com> Signed-off-by: Len Brown <len.brown@intel.com>
2008-12-31ACPI: reboot.c: use new acpi_reset interfaceLin Ming1-1/+1
Use new acpi_reset interface to write to reset register Signed-off-by: Lin Ming <ming.m.lin@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2008-12-31ACPICA: New: acpi_read and acpi_write public interfacesBob Moore1-1/+1
Changed the acpi_hw_low_level_read and acpi_hw_low_level_write functions to the public acpi_read and acpi_write to allow direct access to ACPI registers. Removed the "width" parameter since the width can be obtained from the input GAS structure. Updated the FADT initialization to setup the GAS structures with the proper widths. Some widths are still hardcoded because many FADTs have incorrect register lengths. Signed-off-by: Bob Moore <robert.moore@intel.com Signed-off-by: Lin Ming <ming.m.lin@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2008-11-07Revert "ACPI: Ingore the RESET_REG_SUP bit when using ACPI reset mechanism"Len Brown1-22/+3
This reverts commit 8fd145917fb62368a9b80db59562c20576238f5a. http://bugzilla.kernel.org/show_bug.cgi?id=11942 Signed-off-by: Len Brown <len.brown@intel.com>
2008-10-18ACPI: Ingore the RESET_REG_SUP bit when using ACPI reset mechanismZhao Yakui1-3/+22
According to ACPI 3.0, FADT.flags.RESET_REG_SUP indicates whether the ACPI reboot mechanism is supported. However, some boxes have this bit clear, have a valid ACPI_RESET_REG & RESET_VALUE, and ACPI reboot is the only mechanism that works for them after S3. This suggests that other operating systems may not be checking the RESET_REG_SUP bit, and are using other means to decide whether to use the ACPI reboot mechanism or not. Here we stop checking RESET_REG_SUP. Instead, When acpi reboot is requested, only the reset_register is checked. If the following conditions are met, it indicates that the reset register is supported. a. reset_register is not zero b. the access width is eight c. the bit_offset is zero http://bugzilla.kernel.org/show_bug.cgi?id=7299 http://bugzilla.kernel.org/show_bug.cgi?id=1148 Signed-off-by: Zhao Yakui <yakui.zhao@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2008-07-17Add the ability to reset the machine using the RESET_REG in ACPI's FADT table.Aaron Durbin1-0/+50
Signed-off-by: Aaron Durbin <adurbin@google.com> Signed-off-by: Andi Kleen <ak@linux.intel.com> Cc: Len Brown <lenb@kernel.org> Cc: Andi Kleen <andi@firstfloor.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>