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2019-06-28x86/hpet: Move clockevents into channelsThomas Gleixner
Instead of allocating yet another data structure, move the clock event data into the channel structure. This allows further consolidation of the reservation code and the reuse of the cached boot config to replace the extra flags in the clockevent data. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/20190623132436.185851116@linutronix.de
2019-06-28x86/hpet: Remove the unused hpet_msi_read() functionThomas Gleixner
No users. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/20190623132434.553729327@linutronix.de
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman
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>
2015-10-21timers/x86/hpet: Type adjustmentsJan Beulich
Standardize on bool instead of an inconsistent mixture of u8 and plain 'int'. Also use u32 or 'unsigned int' instead of 'unsigned long' when a 32-bit type suffices, generating slightly better code on x86-64. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/5624E3A002000078000AC49A@prv-mh.provo.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-24x86/MSI: Clean up unused MSI related code and interfacesJiang Liu
Now MSI interrupt has been converted to new hierarchical irqdomain interfaces, so remove legacy MSI related code and interfaces. Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: David Cohen <david.a.cohen@linux.intel.com> Cc: Sander Eikelenboom <linux@eikelenboom.it> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dimitri Sivanich <sivanich@sgi.com> Cc: Yijing Wang <wangyijing@huawei.com> Link: http://lkml.kernel.org/r/1428905519-23704-19-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-04-24x86/hpet: Enhance HPET IRQ to support hierarchical irqdomainsJiang Liu
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: David Cohen <david.a.cohen@linux.intel.com> Cc: Sander Eikelenboom <linux@eikelenboom.it> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dimitri Sivanich <sivanich@sgi.com> Cc: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/1428905519-23704-13-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-05-08x86/hpet: Make boot_hpet_disable externFeng Tang
HPET on some platform has accuracy problem. Making "boot_hpet_disable" extern so that we can runtime disable the HPET timer by using quirk to check the platform. Signed-off-by: Feng Tang <feng.tang@intel.com> Cc: Clemens Ladisch <clemens@ladisch.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1398327498-13163-1-git-send-email-feng.tang@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-01-28x86, hpet: Introduce x86_msi_ops.setup_hpet_msiJoerg Roedel
This function pointer can be overwritten by the IRQ remapping code. The irq_remapping_enabled check can be removed from default_setup_hpet_msi. Signed-off-by: Joerg Roedel <joro@8bytes.org> Acked-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-09-01hpet: Remove unused PCI Vendor ID #defineJon Mason
HPET_ID_VENDOR_8086 is defined but never used. It would be a redefine of PCI_VENDOR_ID_INTEL if it was ever used. Signed-off-by: Jon Mason <jdmason@kudzu.us> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-10-12x86: ioapic/hpet: Convert to new chip functionsThomas Gleixner
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-09-15x86: hpet: Work around hardware stupidityThomas Gleixner
This more or less reverts commits 08be979 (x86: Force HPET readback_cmp for all ATI chipsets) and 30a564be (x86, hpet: Restrict read back to affected ATI chipsets) to the status of commit 8da854c (x86, hpet: Erratum workaround for read after write of HPET comparator). The delta to commit 8da854c is mostly comments and the change from WARN_ONCE to printk_once as we know the call path of this function already. This needs really in depth explanation: First of all the HPET design is a complete failure. Having a counter compare register which generates an interrupt on matching values forces the software to do at least one superfluous readback of the counter register. While it is nice in theory to program "absolute" time events it is practically useless because the timer runs at some absurd frequency which can never be matched to real world units. So we are forced to calculate a relative delta and this forces a readout of the actual counter value, adding the delta and programming the compare register. When the delta is small enough we run into the danger that we program a compare value which is already in the past. Due to the compare for equal nature of HPET we need to read back the counter value after writing the compare rehgister (btw. this is necessary for absolute timeouts as well) to make sure that we did not miss the timer event. We try to work around that by setting the minimum delta to a value which is larger than the theoretical time which elapses between the counter readout and the compare register write, but that's only true in theory. A NMI or SMI which hits between the readout and the write can easily push us beyond that limit. This would result in waiting for the next HPET timer interrupt until the 32bit wraparound of the counter happens which takes about 306 seconds. So we designed the next event function to look like: match = read_cnt() + delta; write_compare_ref(match); return read_cnt() < match ? 0 : -ETIME; At some point we got into trouble with certain ATI chipsets. Even the above "safe" procedure failed. The reason was that the write to the compare register was delayed probably for performance reasons. The theory was that they wanted to avoid the synchronization of the write with the HPET clock, which is understandable. So the write does not hit the compare register directly instead it goes to some intermediate register which is copied to the real compare register in sync with the HPET clock. That opens another window for hitting the dreaded "wait for a wraparound" problem. To work around that "optimization" we added a read back of the compare register which either enforced the update of the just written value or just delayed the readout of the counter enough to avoid the issue. We unfortunately never got any affirmative info from ATI/AMD about this. One thing is sure, that we nuked the performance "optimization" that way completely and I'm pretty sure that the result is worse than before some HW folks came up with those. Just for paranoia reasons I added a check whether the read back compare register value was the same as the value we wrote right before. That paranoia check triggered a couple of years after it was added on an Intel ICH9 chipset. Venki added a workaround (commit 8da854c) which was reading the compare register twice when the first check failed. We considered this to be a penalty in general and restricted the readback (thus the wasted CPU cycles) to the known to be affected ATI chipsets. This turned out to be a utterly wrong decision. 2.6.35 testers experienced massive problems and finally one of them bisected it down to commit 30a564be which spured some further investigation. Finally we got confirmation that the write to the compare register can be delayed by up to two HPET clock cycles which explains the problems nicely. All we can do about this is to go back to Venki's initial workaround in a slightly modified version. Just for the record I need to say, that all of this could have been avoided if hardware designers and of course the HPET committee would have thought about the consequences for a split second. It's out of my comprehension why designing a working timer is so hard. There are two ways to achieve it: 1) Use a counter wrap around aware compare_reg <= counter_reg implementation instead of the easy compare_reg == counter_reg Downsides: - It needs more silicon. - It needs a readout of the counter to apply a relative timeout. This is necessary as the counter does not run in any useful (and adjustable) frequency and there is no guarantee that the counter which is used for timer events is the same which is used for reading the actual time (and therefor for calculating the delta) Upsides: - None 2) Use a simple down counter for relative timer events Downsides: - Absolute timeouts are not possible, which is not a problem at all in the context of an OS and the expected max. latencies/jitter (also see Downsides of #1) Upsides: - It needs less or equal silicon. - It works ALWAYS - It is way faster than a compare register based solution (One write versus one write plus at least one and up to four reads) I would not be so grumpy about all of this, if I would not have been ignored for many years when pointing out these flaws to various hardware folks. I really hate timers (at least those which seem to be designed by janitors). Though finally we got a reasonable explanation plus a solution and I want to thank all the folks involved in chasing it down and providing valuable input to this. Bisected-by: Nix <nix@esperi.org.uk> Reported-by: Artur Skawina <art.08.09@gmail.com> Reported-by: Damien Wyart <damien.wyart@free.fr> Reported-by: John Drescher <drescherjm@gmail.com> Cc: Venkatesh Pallipadi <venki@google.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Andreas Herrmann <andreas.herrmann3@amd.com> Cc: Borislav Petkov <borislav.petkov@amd.com> Cc: stable@kernel.org Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-04-28x86, hpet: Restrict read back to affected ATI chipsetsThomas Gleixner
After programming the HPET, we do a readback as a workaround for ATI/SBx00 chipsets as a synchronization. Unfortunately this triggers an erratum in newer ICH chipsets (ICH9+) where reading the comparator immediately after the write returns the old value. Furthermore, as always, I/O reads are bad for performance. Therefore, restrict the readback to the chipsets that need it, or, for debugging purposes, when we are running with hpet=verbose. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Venkatesh Pallipadi <venki@google.com> LKML-Reference: <20100225185348.GA9674@linux-os.sc.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-01-23x86: Disable HPET MSI on ATI SB700/SB800Pallipadi, Venkatesh
HPET MSI on platforms with ATI SB700/SB800 as they seem to have some side-effects on floppy DMA. Do not use HPET MSI on such platforms. Original problem report from Mark Hounschell http://lkml.indiana.edu/hypermail/linux/kernel/0912.2/01118.html [ This patch needs to go to stable as well. But, there are some conflicts that prevents the patch from going as is. I can rebase/resubmit to stable once the patch goes upstream. hpa: still Cc:'ing stable@ as an FYI. ] Tested-by: Mark Hounschell <markh@compro.net> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Cc: <stable@kernel.org> LKML-Reference: <20100121190952.GA32523@linux-os.sc.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-27x86: arch specific support for remapping HPET MSIsSuresh Siddha
x86 arch support for remapping HPET MSI's by associating the HPET timer block with the interrupt-remapping HW unit and setting up appropriate irq_chip Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Cc: Jay Fenlason <fenlason@redhat.com> LKML-Reference: <20090804190729.630510000@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-21x86, hpet: Simplify the HPET codeJan Beulich
On 64-bits, using unsigned long when unsigned int suffices needlessly creates larger code (due to the need for REX prefixes), and most of the logic in hpet.c really doesn't need 64-bit operations. At once this avoids the need for a couple of type casts. Signed-off-by: Jan Beulich <jbeulich@novell.com> Cc: Shaohua Li <shaohua.li@intel.com> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> LKML-Reference: <4A8BC9780200007800010832@vpn.id2.novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-22x86: Fix ASM_X86__ header guardsH. Peter Anvin
Change header guards named "ASM_X86__*" to "_ASM_X86_*" since: a. the double underscore is ugly and pointless. b. no leading underscore violates namespace constraints. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22x86, um: ... and asm-x86 moveAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>