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2020-08-15Merge tag 'x86-urgent-2020-08-15' of ↵Linus Torvalds1-2/+7
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Misc fixes and small updates all around the place: - Fix mitigation state sysfs output - Fix an FPU xstate/sxave code assumption bug triggered by Architectural LBR support - Fix Lightning Mountain SoC TSC frequency enumeration bug - Fix kexec debug output - Fix kexec memory range assumption bug - Fix a boundary condition in the crash kernel code - Optimize porgatory.ro generation a bit - Enable ACRN guests to use X2APIC mode - Reduce a __text_poke() IRQs-off critical section for the benefit of PREEMPT_RT" * tag 'x86-urgent-2020-08-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/alternatives: Acquire pte lock with interrupts enabled x86/bugs/multihit: Fix mitigation reporting when VMX is not in use x86/fpu/xstate: Fix an xstate size check warning with architectural LBRs x86/purgatory: Don't generate debug info for purgatory.ro x86/tsr: Fix tsc frequency enumeration bug on Lightning Mountain SoC kexec_file: Correctly output debugging information for the PT_LOAD ELF header kexec: Improve & fix crash_exclude_mem_range() to handle overlapping ranges x86/crash: Correct the address boundary of function parameters x86/acrn: Remove redundant chars from ACRN signature x86/acrn: Allow ACRN guest to use X2APIC mode
2020-08-07x86/tsr: Fix tsc frequency enumeration bug on Lightning Mountain SoCDilip Kota1-2/+7
Frequency descriptor of Lightning Mountain SoC doesn't have all the frequency entries so resulting in the below failure causing a kernel hang: Error MSR_FSB_FREQ index 15 is unknown tsc: Fast TSC calibration failed So, add all the frequency entries in the Lightning Mountain SoC frequency descriptor. Fixes: 0cc5359d8fd45 ("x86/cpu: Update init data for new Airmont CPU model") Fixes: 812c2d7506fd ("x86/tsc_msr: Use named struct initializers") Signed-off-by: Dilip Kota <eswara.kota@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Link: https://lore.kernel.org/r/211c643ae217604b46cbec43a2c0423946dc7d2d.1596440057.git.eswara.kota@linux.intel.com
2020-08-06locking/seqlock, headers: Untangle the spaghetti monsterPeter Zijlstra1-0/+1
By using lockdep_assert_*() from seqlock.h, the spaghetti monster attacked. Attack back by reducing seqlock.h dependencies from two key high level headers: - <linux/seqlock.h>: -Remove <linux/ww_mutex.h> - <linux/time.h>: -Remove <linux/seqlock.h> - <linux/sched.h>: +Add <linux/seqlock.h> The price was to add it to sched.h ... Core header fallout, we add direct header dependencies instead of gaining them parasitically from higher level headers: - <linux/dynamic_queue_limits.h>: +Add <asm/bug.h> - <linux/hrtimer.h>: +Add <linux/seqlock.h> - <linux/ktime.h>: +Add <asm/bug.h> - <linux/lockdep.h>: +Add <linux/smp.h> - <linux/sched.h>: +Add <linux/seqlock.h> - <linux/videodev2.h>: +Add <linux/kernel.h> Arch headers fallout: - PARISC: <asm/timex.h>: +Add <asm/special_insns.h> - SH: <asm/io.h>: +Add <asm/page.h> - SPARC: <asm/timer_64.h>: +Add <uapi/asm/asi.h> - SPARC: <asm/vvar.h>: +Add <asm/processor.h>, <asm/barrier.h> -Remove <linux/seqlock.h> - X86: <asm/fixmap.h>: +Add <asm/pgtable_types.h> -Remove <asm/acpi.h> There's also a bunch of parasitic header dependency fallout in .c files, not listed separately. [ mingo: Extended the changelog, split up & fixed the original patch. ] Co-developed-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200804133438.GK2674@hirez.programming.kicks-ass.net
2020-03-30Merge tag 'x86-timers-2020-03-30' of ↵Linus Torvalds1-16/+112
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 timer updates from Thomas Gleixner: "A series of commits to make the MSR derived CPU and TSC frequency more accurate. It turned out that the frequency tables which have been taken from the SDM are inaccurate because the SDM provides truncated and rounded values, e.g. 83.3Mhz (83.3333...) or 116.7Mhz (116.6666...). This causes time drift in the range of ~1 second per hour (20-30 seconds per day). On some of these SoCs it's not possible to recalibrate the TSC because there is no reference (PIT, HPET) available. With some reverse engineering it was established that the possible frequencies are derived from the base clock with fixed multiplier / divider pairs. For the CPU models which have a known crystal frequency the kernel now uses multiplier / divider pairs which bring the frequencies closer to reality and fix the observed time drift issues" * tag 'x86-timers-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/tsc_msr: Make MSR derived TSC frequency more accurate x86/tsc_msr: Fix MSR_FSB_FREQ mask for Cherry Trail devices x86/tsc_msr: Use named struct initializers
2020-03-24x86/kernel: Convert to new CPU match macrosThomas Gleixner1-7/+7
The new macro set has a consistent namespace and uses C99 initializers instead of the grufty C89 ones. Get rid the of the local macro wrappers for consistency. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lkml.kernel.org/r/20200320131509.250559388@linutronix.de
2020-03-11x86/tsc_msr: Make MSR derived TSC frequency more accurateHans de Goede1-11/+86
The "Intel 64 and IA-32 Architectures Software Developer’s Manual Volume 4: Model-Specific Registers" has the following table for the values from freq_desc_byt: 000B: 083.3 MHz 001B: 100.0 MHz 010B: 133.3 MHz 011B: 116.7 MHz 100B: 080.0 MHz Notice how for e.g the 83.3 MHz value there are 3 significant digits, which translates to an accuracy of a 1000 ppm, where as a typical crystal oscillator is 20 - 100 ppm, so the accuracy of the frequency format used in the Software Developer’s Manual is not really helpful. As far as we know Bay Trail SoCs use a 25 MHz crystal and Cherry Trail uses a 19.2 MHz crystal, the crystal is the source clock for a root PLL which outputs 1600 and 100 MHz. It is unclear if the root PLL outputs are used directly by the CPU clock PLL or if there is another PLL in between. This does not matter though, we can model the chain of PLLs as a single PLL with a quotient equal to the quotients of all PLLs in the chain multiplied. So we can create a simplified model of the CPU clock setup using a reference clock of 100 MHz plus a quotient which gets us as close to the frequency from the SDM as possible. For the 83.3 MHz example from above this would give 100 MHz * 5 / 6 = 83 and 1/3 MHz, which matches exactly what has been measured on actual hardware. Use a simplified PLL model with a reference clock of 100 MHz for all Bay and Cherry Trail models. This has been tested on the following models: CPU freq before: CPU freq after: Intel N2840 2165.800 MHz 2166.667 MHz Intel Z3736 1332.800 MHz 1333.333 MHz Intel Z3775 1466.300 MHz 1466.667 MHz Intel Z8350 1440.000 MHz 1440.000 MHz Intel Z8750 1600.000 MHz 1600.000 MHz This fixes the time drifting by about 1 second per hour (20 - 30 seconds per day) on (some) devices which rely on the tsc_msr.c code to determine the TSC frequency. Reported-by: Vipul Kumar <vipulk0511@gmail.com> Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20200223140610.59612-3-hdegoede@redhat.com
2020-03-11x86/tsc_msr: Fix MSR_FSB_FREQ mask for Cherry Trail devicesHans de Goede1-2/+15
According to the "Intel 64 and IA-32 Architectures Software Developer's Manual Volume 4: Model-Specific Registers" on Cherry Trail (Airmont) devices the 4 lowest bits of the MSR_FSB_FREQ mask indicate the bus freq unlike on e.g. Bay Trail where only the lowest 3 bits are used. This is also the reason why MAX_NUM_FREQS is defined as 9, since Cherry Trail SoCs have 9 possible frequencies, so the lo value from the MSR needs to be masked with 0x0f, not with 0x07 otherwise the 9th frequency will get interpreted as the 1st. Bump MAX_NUM_FREQS to 16 to avoid any possibility of addressing the array out of bounds and makes the mask part of the cpufreq struct so it can be set it per model. While at it also log an error when the index points to an uninitialized part of the freqs lookup-table. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20200223140610.59612-2-hdegoede@redhat.com
2020-03-11x86/tsc_msr: Use named struct initializersHans de Goede1-10/+18
Use named struct initializers for the freq_desc struct-s initialization and change the "u8 msr_plat" to a "bool use_msr_plat" to make its meaning more clear instead of relying on a comment to explain it. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20200223140610.59612-1-hdegoede@redhat.com
2019-09-06x86/cpu: Update init data for new Airmont CPU modelRahul Tanwar1-0/+5
Update properties for newly added Airmont CPU variant. Signed-off-by: Rahul Tanwar <rahul.tanwar@linux.intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com> Cc: Gayatri Kammela <gayatri.kammela@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190905193020.14707-5-tony.luck@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-05-09x86/apic: Rename 'lapic_timer_frequency' to 'lapic_timer_period'Daniel Drake1-2/+2
This variable is a period unit (number of clock cycles per jiffy), not a frequency (which is number of cycles per second). Give it a more appropriate name. Suggested-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Daniel Drake <drake@endlessm.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: len.brown@intel.com Cc: linux@endlessm.com Cc: rafael.j.wysocki@intel.com Link: http://lkml.kernel.org/r/20190509055417.13152-2-drake@endlessm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-02x86/cpu: Sanitize FAM6_ATOM namingPeter Zijlstra1-5/+5
Going primarily by: https://en.wikipedia.org/wiki/List_of_Intel_Atom_microprocessors with additional information gleaned from other related pages; notably: - Bonnell shrink was called Saltwell - Moorefield is the Merriefield refresh which makes it Airmont The general naming scheme is: FAM6_ATOM_UARCH_SOCTYPE for i in `git grep -l FAM6_ATOM` ; do sed -i -e 's/ATOM_PINEVIEW/ATOM_BONNELL/g' \ -e 's/ATOM_LINCROFT/ATOM_BONNELL_MID/' \ -e 's/ATOM_PENWELL/ATOM_SALTWELL_MID/g' \ -e 's/ATOM_CLOVERVIEW/ATOM_SALTWELL_TABLET/g' \ -e 's/ATOM_CEDARVIEW/ATOM_SALTWELL/g' \ -e 's/ATOM_SILVERMONT1/ATOM_SILVERMONT/g' \ -e 's/ATOM_SILVERMONT2/ATOM_SILVERMONT_X/g' \ -e 's/ATOM_MERRIFIELD/ATOM_SILVERMONT_MID/g' \ -e 's/ATOM_MOOREFIELD/ATOM_AIRMONT_MID/g' \ -e 's/ATOM_DENVERTON/ATOM_GOLDMONT_X/g' \ -e 's/ATOM_GEMINI_LAKE/ATOM_GOLDMONT_PLUS/g' ${i} done Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: dave.hansen@linux.intel.com Cc: len.brown@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-03x86/platform/intel-mid: Remove custom TSC calibrationAndy Shevchenko1-0/+5
Since the commit 7da7c1561366 ("x86, tsc: Add static (MSR) TSC calibration on Intel Atom SoCs") introduced a common way for all Intel MID chips to get their TSC frequency via MSRs, there is no need to keep a duplication in each of Intel MID platform code. Thus, remove the custom calibration code for good. Note, there is slight difference in how to get frequency for (reserved?) values in MSRs, i.e. legacy code enforces some defaults while new code just uses 0 in that cases. Suggested-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Bin Gao <bin.gao@intel.com> Link: https://lkml.kernel.org/r/20180629193113.84425-6-andriy.shevchenko@linux.intel.com
2018-07-03x86/tsc: Use SPDX identifier and update Intel copyrightAndy Shevchenko1-4/+3
Use SPDX identifier and update year in Intel copyright line. While here, remove file name from the file itself. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Pavel Tatashin <pasha.tatashin@oracle.com> Link: https://lkml.kernel.org/r/20180629193113.84425-5-andriy.shevchenko@linux.intel.com
2018-07-03x86/tsc: Convert to use x86_match_cpu() and INTEL_CPU_FAM6()Andy Shevchenko1-41/+42
Move the code to use recently introduced INTEL_CPU_FAM6() macro and drop custom version of x86_match_cpu() function. No functional change intended. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Pavel Tatashin <pasha.tatashin@oracle.com> Link: https://lkml.kernel.org/r/20180629193113.84425-3-andriy.shevchenko@linux.intel.com
2018-07-03x86/tsc: Add missing header to tsc_msr.cAndy Shevchenko1-0/+1
Add a missing header otherwise compiler warns about missed prototype: CC arch/x86/kernel/tsc_msr.o arch/x86/kernel/tsc_msr.c:73:15: warning: no previous prototype for ‘cpu_khz_from_msr’ [-Wmissing-prototypes] unsigned long cpu_khz_from_msr(void) ^~~~~~~~~~~~~~~~ Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Pavel Tatashin <pasha.tatashin@oracle.com> Link: https://lkml.kernel.org/r/20180629193113.84425-4-andriy.shevchenko@linux.intel.com
2016-11-18x86/tsc: Set TSC_KNOWN_FREQ and TSC_RELIABLE flags on Intel Atom SoCsBin Gao1-0/+19
TSC on Intel Atom SoCs capable of determining TSC frequency by MSR is reliable and the frequency is known (provided by HW). On these platforms PIT/HPET is generally not available so calibration won't work at all and there is no other clocksource to act as a watchdog for the TSC, so we have no other choice than to trust it. Set both X86_FEATURE_TSC_KNOWN_FREQ and X86_FEATURE_TSC_RELIABLE flags to make sure the calibration is skipped and no watchdog is required. Signed-off-by: Bin Gao <bin.gao@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1479241644-234277-5-git-send-email-bin.gao@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-07-11x86/tsc_msr: Remove irqoff around MSR-based TSC enumerationLen Brown1-1/+1
Remove the irqoff/irqon around MSR-based TSC enumeration, as it is not necessary. Also rename: try_msr_calibrate_tsc() to cpu_khz_from_msr(), as that better describes what the routine does. Signed-off-by: Len Brown <len.brown@intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/a6b5c3ecd3b068175d2309599ab28163fc34215e.1466138954.git.len.brown@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-10x86/tsc_msr: Add Airmont reference clock valuesLen Brown1-1/+4
per the Intel 64 and IA-32 Architecture Software Developer's Manual... Add the reference clock for Intel Atom Processors Based on the Airmont Microarchitecture. Reported-by: Stephane Gasparini <stephane.gasparini@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/abc6a0f4b18281410da1a3f26e2819d8e03e144f.1466138954.git.len.brown@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-10x86/tsc_msr: Correct Silvermont reference clock valuesLen Brown1-3/+3
Atom processors use a 19.2 MHz crystal oscillator. Early processors generate 100 MHz via 19.2 MHz * 26 / 5 = 99.84 MHz. Later preocessor generate 100 MHz via 19.2 MHz * 125 / 24 = 100 MHz. Update the Silvermont-based tables accordingly, matching the Software Developers Manual. Also, correct a 166 MHz entry that should have been 116 MHz, and add a missing 80 MHz entry. Reported-by: Stephane Gasparini <stephane.gasparini@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/5d7561655dfb066ff10801b423405bae4d1cfbe2.1466138954.git.len.brown@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-10x86/tsc_msr: Update comments, expand definitionsLen Brown1-26/+10
Syntax only, no functional change. Signed-off-by: Len Brown <len.brown@intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/8653a2dba21fef122fc7b29eafb750e2004d3976.1466138954.git.len.brown@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-10x86/tsc_msr: Remove debugging messagesLen Brown1-16/+3
Debugging messages are not necessary after all of the possible hardware failures that never occur. Instead, this code can simply return 0. This code also doesn't need to print in the success case. tsc_init() already prints the TSC frequency, and apic=debug is available if anybody really is interested in printing the LAPIC frequency. Signed-off-by: Len Brown <len.brown@intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/cf03279a125b95dfa9b8d3d5b4a66de09cd04050.1466138954.git.len.brown@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-10x86/tsc_msr: Identify Intel-specific codeLen Brown1-0/+3
try_msr_calibrate_tsc() is currently Intel-specific, and should not execute on any other vendor's parts. Signed-off-by: Len Brown <len.brown@intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1fe23c052826bdcfeb3d45045aa02246078cb5a7.1466138954.git.len.brown@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-10Revert "x86/tsc: Add missing Cherrytrail frequency to the table"Len Brown1-3/+0
This reverts commit: e2724e9d9692 ("x86/tsc: Add missing Cherrytrail frequency to the table") ... as it is incomplete, and is replaced by a more complete patch later in this series. Signed-off-by: Len Brown <len.brown@intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/2199d0e959f7f71a18827268b5d060f8d3831639.1466138954.git.len.brown@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-12x86/tsc: Add missing Cherrytrail frequency to the tableJeremy Compostella1-0/+3
Intel Cherrytrail is based on Airmont core so MSR_FSB_FREQ[2:0] = 4 means that the CPU reference clock runs at 80MHz. Add this missing frequency to the table. Signed-off-by: Jeremy Compostella <jeremy.compostella@intel.com> Link: http://lkml.kernel.org/r/87y47gty89.fsf@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-05-06x86/tsc: Read all ratio bits from MSR_PLATFORM_INFOChen Yu1-1/+1
Currently we read the tsc radio: ratio = (MSR_PLATFORM_INFO >> 8) & 0x1f; Thus we get bit 8-12 of MSR_PLATFORM_INFO, however according to the SDM (35.5), the ratio bits are bit 8-15. Ignoring the upper bits can result in an incorrect tsc ratio, which causes the TSC calibration and the Local APIC timer frequency to be incorrect. Fix this problem by masking 0xff instead. [ tglx: Massaged changelog ] Fixes: 7da7c1561366 "x86, tsc: Add static (MSR) TSC calibration on Intel Atom SoCs" Signed-off-by: Chen Yu <yu.c.chen@intel.com> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: stable@vger.kernel.org Cc: Bin Gao <bin.gao@intel.com> Cc: Len Brown <lenb@kernel.org> Link: http://lkml.kernel.org/r/1462505619-5516-1-git-send-email-yu.c.chen@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-02-19x86: tsc: Add missing Baytrail frequency to the tableMika Westerberg1-1/+1
Intel Baytrail is based on Silvermont core so MSR_FSB_FREQ[2:0] == 0 means that the CPU reference clock runs at 83.3MHz. Add this missing frequency to the table. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: Bin Gao <bin.gao@linux.intel.com> Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> Cc: Ingo Molnar <mingo@kernel.org> Cc: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/r/1392810750-18660-2-git-send-email-mika.westerberg@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-02-19x86, tsc: Fallback to normal calibration if fast MSR calibration failsThomas Gleixner1-14/+14
If we cannot calibrate TSC via MSR based calibration try_msr_calibrate_tsc() stores zero to fast_calibrate and returns that to the caller. This value gets then propagated further to clockevents code resulting division by zero oops like the one below: divide error: 0000 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W 3.13.0+ #47 task: ffff880075508000 ti: ffff880075506000 task.ti: ffff880075506000 RIP: 0010:[<ffffffff810aec14>] [<ffffffff810aec14>] clockevents_config.part.3+0x24/0xa0 RSP: 0000:ffff880075507e58 EFLAGS: 00010246 RAX: ffffffffffffffff RBX: ffff880079c0cd80 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffffffffffff RBP: ffff880075507e70 R08: 0000000000000001 R09: 00000000000000be R10: 00000000000000bd R11: 0000000000000003 R12: 000000000000b008 R13: 0000000000000008 R14: 000000000000b010 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff880079c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: ffff880079fff000 CR3: 0000000001c0b000 CR4: 00000000001006f0 Stack: ffff880079c0cd80 000000000000b008 0000000000000008 ffff880075507e88 ffffffff810aecb0 ffff880079c0cd80 ffff880075507e98 ffffffff81030168 ffff880075507ed8 ffffffff81d1104f 00000000000000c3 0000000000000000 Call Trace: [<ffffffff810aecb0>] clockevents_config_and_register+0x20/0x30 [<ffffffff81030168>] setup_APIC_timer+0xc8/0xd0 [<ffffffff81d1104f>] setup_boot_APIC_clock+0x4cc/0x4d8 [<ffffffff81d0f5de>] native_smp_prepare_cpus+0x3dd/0x3f0 [<ffffffff81d02ee9>] kernel_init_freeable+0xc3/0x205 [<ffffffff8177c910>] ? rest_init+0x90/0x90 [<ffffffff8177c91e>] kernel_init+0xe/0x120 [<ffffffff8178deec>] ret_from_fork+0x7c/0xb0 [<ffffffff8177c910>] ? rest_init+0x90/0x90 Prevent this from happening by: 1) Modifying try_msr_calibrate_tsc() to return calibration value or zero if it fails. 2) Check this return value in native_calibrate_tsc() and in case of zero fallback to use normal non-MSR based calibration. [mw: Added subject and changelog] Reported-and-tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Bin Gao <bin.gao@linux.intel.com> Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> Cc: Ingo Molnar <mingo@kernel.org> Cc: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/r/1392810750-18660-1-git-send-email-mika.westerberg@linux.intel.com Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-01-16x86, tsc, apic: Unbreak static (MSR) calibration when CONFIG_X86_LOCAL_APIC=nH. Peter Anvin1-0/+2
If we aren't going to use the local APIC anyway, we obviously don't care about its timer frequency. Link: http://lkml.kernel.org/r/tip-rgm7xmg7k6qnjlw3ynkcjsmh@git.kernel.org Reported-by: Fengguang Wu <fengguang.wu@intel.com> Cc: Bin Gao <bin.gao@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-01-15x86, tsc: Add static (MSR) TSC calibration on Intel Atom SoCsBin Gao1-0/+125
On SoCs that have the calibration MSRs available, either there is no PIT, HPET or PMTIMER to calibrate against, or the PIT/HPET/PMTIMER is driven from the same clock as the TSC, so calibration is redundant and just slows down the boot. TSC rate is caculated by this formula: <maximum core-clock to bus-clock ratio> * <maximum resolved frequency> The ratio and the resolved frequency ID can be obtained from MSR. See Intel 64 and IA-32 System Programming Guid section 16.12 and 30.11.5 for details. Signed-off-by: Bin Gao <bin.gao@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/n/tip-rgm7xmg7k6qnjlw3ynkcjsmh@git.kernel.org
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-22 11:11:30 +0000