148 Commits
Author SHA1 Message Date
Gregory CLEMENTandThomas Bogendoerfer ab535361ef MIPS: SMP: Move the AP sync point before the calibration delay
In the calibration delay process, some resources are shared, so it's
better to move it after the parallel execution part. Thanks to the
patch optimizing CPU delay calibration, this change has no impact on
the boot time improvements gained from CPU parallel boot.

Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2025-05-25 15:00:23 +02:00
Gregory CLEMENTandThomas Bogendoerfer 4cc7543eb4 MIPS: SMP: Move the AP sync point before the non-parallel aware functions
When CONFIG_HOTPLUG_PARALLEL is enabled, the code executing before
cpuhp_ap_sync_alive() is executed in parallel, while after it is
serialized. The functions set_cpu_sibling_map() and set_cpu_core_map()
were not designed to be executed in parallel, so by moving the
cpuhp_ap_sync_alive() before cpuhp_ap_sync_alive(), we then ensure
they will be called serialized.

The measurement done on EyeQ5 did not show any relevant boot time
increase after applying this patch.

Fixes: 76c43eb507 ("MIPS: SMP: Implement parallel CPU bring up for EyeQ")
Reported-by: Huacai Chen <chenhuacai@kernel.org>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2025-05-20 08:43:24 +02:00
Gregory CLEMENTandThomas Bogendoerfer 76c43eb507 MIPS: SMP: Implement parallel CPU bring up for EyeQ
Added support for starting CPUs in parallel on EyeQ to speed up boot time.

On EyeQ5, booting 8 CPUs is now ~90ms faster.
On EyeQ6, booting 32 CPUs is now ~650ms faster.

Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2025-04-27 09:45:15 +02:00
Bibo MaoandThomas Gleixner 1d07085402 smp: Mark smp_prepare_boot_cpu() __init
smp_prepare_boot_cpu() is only called during boot, hence mark it as
__init.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Huacai Chen <chenhuacai@loongson.cn>
Link: https://lore.kernel.org/all/20240907082720.452148-1-maobibo@loongson.cn
2024-09-08 16:01:10 +02:00
Jiaxun YangandThomas Bogendoerfer 580724fce2 MIPS: sync-r4k: Rework based on x86 tsc_sync
The original sync-r4k did a good job on reducing jitter by determine
the "next time value", but it has a limitation that when synchronization
being performed too many times due to high core count or CPU hotplug,
the timewrap on CPU0 will become unaccpetable.

Rework the mechanism based on latest x86 tsc_sync. (It seems like
the original implementation is based on tsc_sync at that time,
so it's just a refresh.) To improve overall performance.

Tesed on Loongson64, Boston, QEMU.

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-07-03 16:50:12 +02:00
Linus Torvalds 9f2a635235 Merge tag 'mm-nonmm-stable-2024-01-09-10-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton:
 "Quite a lot of kexec work this time around. Many singleton patches in
  many places. The notable patch series are:

   - nilfs2 folio conversion from Matthew Wilcox in 'nilfs2: Folio
     conversions for file paths'.

   - Additional nilfs2 folio conversion from Ryusuke Konishi in 'nilfs2:
     Folio conversions for directory paths'.

   - IA64 remnant removal in Heiko Carstens's 'Remove unused code after
     IA-64 removal'.

   - Arnd Bergmann has enabled the -Wmissing-prototypes warning
     everywhere in 'Treewide: enable -Wmissing-prototypes'. This had
     some followup fixes:

      - Nathan Chancellor has cleaned up the hexagon build in the series
        'hexagon: Fix up instances of -Wmissing-prototypes'.

      - Nathan also addressed some s390 warnings in 's390: A couple of
        fixes for -Wmissing-prototypes'.

      - Arnd Bergmann addresses the same warnings for MIPS in his series
        'mips: address -Wmissing-prototypes warnings'.

   - Baoquan He has made kexec_file operate in a top-down-fitting manner
     similar to kexec_load in the series 'kexec_file: Load kernel at top
     of system RAM if required'

   - Baoquan He has also added the self-explanatory 'kexec_file: print
     out debugging message if required'.

   - Some checkstack maintenance work from Tiezhu Yang in the series
     'Modify some code about checkstack'.

   - Douglas Anderson has disentangled the watchdog code's logging when
     multiple reports are occurring simultaneously. The series is
     'watchdog: Better handling of concurrent lockups'.

   - Yuntao Wang has contributed some maintenance work on the crash code
     in 'crash: Some cleanups and fixes'"

* tag 'mm-nonmm-stable-2024-01-09-10-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (157 commits)
  crash_core: fix and simplify the logic of crash_exclude_mem_range()
  x86/crash: use SZ_1M macro instead of hardcoded value
  x86/crash: remove the unused image parameter from prepare_elf_headers()
  kdump: remove redundant DEFAULT_CRASH_KERNEL_LOW_SIZE
  scripts/decode_stacktrace.sh: strip unexpected CR from lines
  watchdog: if panicking and we dumped everything, don't re-enable dumping
  watchdog/hardlockup: use printk_cpu_sync_get_irqsave() to serialize reporting
  watchdog/softlockup: use printk_cpu_sync_get_irqsave() to serialize reporting
  watchdog/hardlockup: adopt softlockup logic avoiding double-dumps
  kexec_core: fix the assignment to kimage->control_page
  x86/kexec: fix incorrect end address passed to kernel_ident_mapping_init()
  lib/trace_readwrite.c:: replace asm-generic/io with linux/io
  nilfs2: cpfile: fix some kernel-doc warnings
  stacktrace: fix kernel-doc typo
  scripts/checkstack.pl: fix no space expression between sp and offset
  x86/kexec: fix incorrect argument passed to kexec_dprintk()
  x86/kexec: use pr_err() instead of kexec_dprintk() when an error occurs
  nilfs2: add missing set_freezable() for freezable kthread
  kernel: relay: remove relay_file_splice_read dead code, doesn't work
  docs: submit-checklist: remove all of "make namespacecheck"
  ...
2024-01-09 11:46:20 -08:00
Arnd BergmannandAndrew Morton d1f4b2b875 mips: smp: fix setup_profiling_timer() prototype
The function is unconditionally defined in smp.c but is conditionally
declared in a header that is not included here.

arch/mips/kernel/smp.c:473:5: error: no previous prototype for 'setup_profiling_timer' [-Werror=missing-prototypes]

Add the missing #include and #ifdef to match the declaration.

Link: https://lkml.kernel.org/r/20231204115710.2247097-20-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-10 17:21:42 -08:00
Stefan WiehlerandThomas Bogendoerfer 55702ec960 mips/smp: Call rcutree_report_cpu_starting() earlier
rcutree_report_cpu_starting() must be called before
clockevents_register_device() to avoid the following lockdep splat triggered by
calling list_add() when CONFIG_PROVE_RCU_LIST=y:

  WARNING: suspicious RCU usage
  ...
  -----------------------------
  kernel/locking/lockdep.c:3680 RCU-list traversed in non-reader section!!

  other info that might help us debug this:

  RCU used illegally from offline CPU!
  rcu_scheduler_active = 1, debug_locks = 1
  no locks held by swapper/1/0.
  ...
  Call Trace:
  [<ffffffff8012a434>] show_stack+0x64/0x158
  [<ffffffff80a93d98>] dump_stack_lvl+0x90/0xc4
  [<ffffffff801c9e9c>] __lock_acquire+0x1404/0x2940
  [<ffffffff801cbf3c>] lock_acquire+0x14c/0x448
  [<ffffffff80aa4260>] _raw_spin_lock_irqsave+0x50/0x88
  [<ffffffff8021e0c8>] clockevents_register_device+0x60/0x1e8
  [<ffffffff80130ff0>] r4k_clockevent_init+0x220/0x3a0
  [<ffffffff801339d0>] start_secondary+0x50/0x3b8

raw_smp_processor_id() is required in order to avoid calling into lockdep
before RCU has declared the CPU to be watched for readers.

See also commit 29368e0939 ("x86/smpboot:  Move rcu_cpu_starting() earlier"),
commit de5d9dae15 ("s390/smp: move rcu_cpu_starting() earlier") and commit
99f070b623 ("powerpc/smp: Call rcu_cpu_starting() earlier").

Signed-off-by: Stefan Wiehler <stefan.wiehler@nokia.com>
Reviewed-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2023-12-05 18:43:05 +01:00
Linus Torvalds b775d6c585 Merge tag 'mips_6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux
Pull MIPS updates from Thomas Bogendoerfer:

 - add support for TP-Link HC220 G5 v1

 - add support for Wifi/Bluetooth on CI20

 - rework Ralink clock and reset handling

 - cleanups and fixes

* tag 'mips_6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (58 commits)
  MIPS: Loongson64: DTS: Add RTC support to Loongson-2K1000
  MIPS: Loongson64: DTS: Add RTC support to LS7A PCH
  MIPS: OCTEON: octeon-usb: cleanup divider calculation
  MIPS: OCTEON: octeon-usb: introduce dwc3_octeon_{read,write}q
  MIPS: OCTEON: octeon-usb: move gpio config to separate function
  MIPS: OCTEON: octeon-usb: use bitfields for shim register
  MIPS: OCTEON: octeon-usb: use bitfields for host config register
  MIPS: OCTEON: octeon-usb: use bitfields for control register
  MIPS: OCTEON: octeon-usb: add all register offsets
  mips: ralink: match all supported system controller compatible strings
  MIPS: dec: prom: Address -Warray-bounds warning
  MIPS: DTS: CI20: Raise VDDCORE voltage to 1.125 volts
  clk: ralink: mtmips: Fix uninitialized use of ret in mtmips_register_{fixed,factor}_clocks()
  mips: ralink: introduce commonly used remap node function
  mips: pci-mt7620: use dev_info() to log PCIe device detection result
  mips: pci-mt7620: do not print NFTS register value as error log
  MAINTAINERS: add Mediatek MTMIPS Clock maintainer
  mips: ralink: get cpu rate from new driver code
  mips: ralink: remove reset related code
  mips: ralink: mt7620: remove clock related code
  ...
2023-06-29 15:01:51 -07:00
Jiaxun YangandThomas Bogendoerfer 96cb8ae28c MIPS: Rework smt cmdline parameters
Provide a generic smt parameters interface aligned with s390
to allow users to limit smt usage and threads per core.

It replaced previous undocumented "nothreads" parameter for
smp-cps which is ambiguous and does not cover smp-mt.

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2023-06-09 10:34:14 +02:00
Thomas GleixnerandPeter Zijlstra c8d2bcc467 MIPS: SMP_CPS: Switch to hotplug core state synchronization
Switch to the CPU hotplug core state tracking and synchronization
mechanim. This unfortunately requires to add dead reporting to the non CPS
platforms as CPS is the only user, but it allows an overall consolidation
of this functionality.

No functional change intended.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Helge Deller <deller@gmx.de> # parisc
Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck
Link: https://lore.kernel.org/r/20230512205256.803238859@linutronix.de
2023-05-15 13:44:58 +02:00
Mao BiboandThomas Bogendoerfer 84595f450a MIPS: smp: optimization for flush_tlb_mm when exiting
When process exits or execute new binary, it will call function
exit_mmap with old mm, there is such function call trace:
  exit_mmap(struct mm_struct *mm)
      --> tlb_finish_mmu(&tlb, 0, -1)
         --> arch_tlb_finish_mmu(tlb, start, end, force)
	    --> tlb_flush_mmu(tlb);
               --> tlb_flush(struct mmu_gather *tlb)
                  --> flush_tlb_mm(tlb->mm)

It is not necessary to flush tlb since oldmm is not used anymore
by the process, there is similar operations on IA64/ARM64 etc,
this patch adds such optimization on MIPS.

Signed-off-by: Mao Bibo <maobibo@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2022-05-12 17:56:21 +02:00
Alexander LobakinandThomas Bogendoerfer f2703def33 MIPS: smp: fill in sibling and core maps earlier
After enabling CONFIG_SCHED_CORE (landed during 5.14 cycle),
2-core 2-thread-per-core interAptiv (CPS-driven) started emitting
the following:

[    0.025698] CPU1 revision is: 0001a120 (MIPS interAptiv (multi))
[    0.048183] ------------[ cut here ]------------
[    0.048187] WARNING: CPU: 1 PID: 0 at kernel/sched/core.c:6025 sched_core_cpu_starting+0x198/0x240
[    0.048220] Modules linked in:
[    0.048233] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.17.0-rc3+ #35 b7b319f24073fd9a3c2aa7ad15fb7993eec0b26f
[    0.048247] Stack : 817f0000 00000004 327804c8 810eb050 00000000 00000004 00000000 c314fdd1
[    0.048278]         830cbd64 819c0000 81800000 817f0000 83070bf4 00000001 830cbd08 00000000
[    0.048307]         00000000 00000000 815fcbc4 00000000 00000000 00000000 00000000 00000000
[    0.048334]         00000000 00000000 00000000 00000000 817f0000 00000000 00000000 817f6f34
[    0.048361]         817f0000 818a3c00 817f0000 00000004 00000000 00000000 4dc33260 0018c933
[    0.048389]         ...
[    0.048396] Call Trace:
[    0.048399] [<8105a7bc>] show_stack+0x3c/0x140
[    0.048424] [<8131c2a0>] dump_stack_lvl+0x60/0x80
[    0.048440] [<8108b5c0>] __warn+0xc0/0xf4
[    0.048454] [<8108b658>] warn_slowpath_fmt+0x64/0x10c
[    0.048467] [<810bd418>] sched_core_cpu_starting+0x198/0x240
[    0.048483] [<810c6514>] sched_cpu_starting+0x14/0x80
[    0.048497] [<8108c0f8>] cpuhp_invoke_callback_range+0x78/0x140
[    0.048510] [<8108d914>] notify_cpu_starting+0x94/0x140
[    0.048523] [<8106593c>] start_secondary+0xbc/0x280
[    0.048539]
[    0.048543] ---[ end trace 0000000000000000 ]---
[    0.048636] Synchronize counters for CPU 1: done.

...for each but CPU 0/boot.
Basic debug printks right before the mentioned line say:

[    0.048170] CPU: 1, smt_mask:

So smt_mask, which is sibling mask obviously, is empty when entering
the function.
This is critical, as sched_core_cpu_starting() calculates
core-scheduling parameters only once per CPU start, and it's crucial
to have all the parameters filled in at that moment (at least it
uses cpu_smt_mask() which in fact is `&cpu_sibling_map[cpu]` on
MIPS).

A bit of debugging led me to that set_cpu_sibling_map() performing
the actual map calculation, was being invocated after
notify_cpu_start(), and exactly the latter function starts CPU HP
callback round (sched_core_cpu_starting() is basically a CPU HP
callback).
While the flow is same on ARM64 (maps after the notifier, although
before calling set_cpu_online()), x86 started calculating sibling
maps earlier than starting the CPU HP callbacks in Linux 4.14 (see
[0] for the reference). Neither me nor my brief tests couldn't find
any potential caveats in calculating the maps right after performing
delay calibration, but the WARN splat is now gone.
The very same debug prints now yield exactly what I expected from
them:

[    0.048433] CPU: 1, smt_mask: 0-1

[0] https://git.kernel.org/pub/scm/linux/kernel/git/mips/linux.git/commit/?id=76ce7cfe35ef

Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2022-02-16 20:48:10 +01:00
Valentin SchneiderandIngo Molnar f1a0a376ca sched/core: Initialize the idle task with preemption disabled
As pointed out by commit

  de9b8f5dcb ("sched: Fix crash trying to dequeue/enqueue the idle thread")

init_idle() can and will be invoked more than once on the same idle
task. At boot time, it is invoked for the boot CPU thread by
sched_init(). Then smp_init() creates the threads for all the secondary
CPUs and invokes init_idle() on them.

As the hotplug machinery brings the secondaries to life, it will issue
calls to idle_thread_get(), which itself invokes init_idle() yet again.
In this case it's invoked twice more per secondary: at _cpu_up(), and at
bringup_cpu().

Given smp_init() already initializes the idle tasks for all *possible*
CPUs, no further initialization should be required. Now, removing
init_idle() from idle_thread_get() exposes some interesting expectations
with regards to the idle task's preempt_count: the secondary startup always
issues a preempt_disable(), requiring some reset of the preempt count to 0
between hot-unplug and hotplug, which is currently served by
idle_thread_get() -> idle_init().

Given the idle task is supposed to have preemption disabled once and never
see it re-enabled, it seems that what we actually want is to initialize its
preempt_count to PREEMPT_DISABLED and leave it there. Do that, and remove
init_idle() from idle_thread_get().

Secondary startups were patched via coccinelle:

  @begone@
  @@

  -preempt_disable();
  ...
  cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210512094636.2958515-1-valentin.schneider@arm.com
2021-05-12 13:01:45 +02:00
Bhaskar ChowdhuryandThomas Bogendoerfer a056aacd2d arch: mips: kernel: Fix two spelling in smp.c
s/logcal/logical/
s/intercpu/inter-CPU/

Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2021-02-03 11:33:48 +01:00
Peter Zijlstra 545b8c8df4 smp: Cleanup smp_call_function*()
Get rid of the __call_single_node union and cleanup the API a little
to avoid external code relying on the structure layout as much.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
2020-11-24 16:47:49 +01:00
Linus Torvalds d71e064449 Merge tag 'mips_5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux
Pull MIPS updates from Thomas Bogendoerfer:

 - loongson64 irq rework

 - dmi support loongson

 - replace setup_irq() by request_irq()

 - jazz cleanups

 - minor cleanups and fixes

* tag 'mips_5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (44 commits)
  MIPS: ralink: mt7621: Fix soc_device introduction
  MIPS: Exclude more dsemul code when CONFIG_MIPS_FP_SUPPORT=n
  MIPS/tlbex: Fix LDDIR usage in setup_pw() for Loongson-3
  MIPS: do not compile generic functions for CONFIG_CAVIUM_OCTEON_SOC
  MAINTAINERS: Update Loongson64 entry
  MIPS: Loongson64: Load built-in dtbs
  MIPS: Loongson64: Add generic dts
  dt-bindings: mips: Add loongson boards
  MIPS: Loongson64: Drop legacy IRQ code
  dt-bindings: interrupt-controller: Add Loongson-3 HTPIC
  irqchip: Add driver for Loongson-3 HyperTransport PIC controller
  dt-bindings: interrupt-controller: Add Loongson LIOINTC
  irqchip: loongson-liointc: Workaround LPC IRQ Errata
  irqchip: Add driver for Loongson I/O Local Interrupt Controller
  docs: mips: remove no longer needed au1xxx_ide.rst documentation
  MIPS: Alchemy: remove no longer used au1xxx_ide.h header
  ide: remove no longer used au1xxx-ide driver
  MIPS: Add support for Desktop Management Interface (DMI)
  firmware: dmi: Add macro SMBIOS_ENTRY_POINT_SCAN_START
  MIPS: ralink: mt7621: introduce 'soc_device' initialization
  ...
2020-03-31 08:51:45 -07:00
Peter XuandIngo Molnar e188f0a50f MIPS: smp: Remove tick_broadcast_count
Now smp_call_function_single_async() provides the protection that
we'll return with -EBUSY if the csd object is still pending, then we
don't need the tick_broadcast_count counter any more.

Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20191216213125.9536-3-peterx@redhat.com
2020-03-06 13:42:28 +01:00
afzal mohammedandThomas Bogendoerfer ac8fd122e0 MIPS: Replace setup_irq() by request_irq()
request_irq() is preferred over setup_irq(). Invocations of setup_irq()
occur after memory allocators are ready.

Per tglx[1], setup_irq() existed in olden days when allocators were not
ready by the time early interrupts were initialized.

Hence replace setup_irq() by request_irq().

remove_irq() has been replaced by free_irq() as well.

There were build error's during previous version, couple of which was
reported by kbuild test robot <lkp@intel.com> of which one was reported
by Thomas Bogendoerfer <tsbogend@alpha.franken.de> as well. There were a
few more issues including build errors, those also have been fixed.

[1] https://lkml.kernel.org/r/alpine.DEB.2.20.1710191609480.1971@nanos

Signed-off-by: afzal mohammed <afzal.mohd.ma@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-03-05 16:47:35 +01:00
Thomas GleixnerandGreg Kroah-Hartman 1a59d1b8e0 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:35 -07:00
Thomas BogendoerferandPaul Burton 2c86562047 MIPS: SGI-IP27: do boot CPU init later
To make use of per_cpu variables in interrupt code per_cpu_init() must
be done after setup_per_cpu_areas(). This is achieved by calling it
in smp_prepare_boot_cpu() via a new smp_ops method.

Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
2019-02-19 12:46:03 -08:00
Paul Burton c8790d657b MIPS: MemoryMapID (MMID) Support
Introduce support for using MemoryMapIDs (MMIDs) as an alternative to
Address Space IDs (ASIDs). The major difference between the two is that
MMIDs are global - ie. an MMID uniquely identifies an address space
across all coherent CPUs. In contrast ASIDs are non-global per-CPU IDs,
wherein each address space is allocated a separate ASID for each CPU
upon which it is used. This global namespace allows a new GINVT
instruction be used to globally invalidate TLB entries associated with a
particular MMID across all coherent CPUs in the system, removing the
need for IPIs to invalidate entries with separate ASIDs on each CPU.

The allocation scheme used here is largely borrowed from arm64 (see
arch/arm64/mm/context.c). In essence we maintain a bitmap to track
available MMIDs, and MMIDs in active use at the time of a rollover to a
new MMID version are preserved in the new version. The allocation scheme
requires efficient 64 bit atomics in order to perform reasonably, so
this support depends upon CONFIG_GENERIC_ATOMIC64=n (ie. currently it
will only be included in MIPS64 kernels).

The first, and currently only, available CPU with support for MMIDs is
the MIPS I6500. This CPU supports 16 bit MMIDs, and so for now we cap
our MMIDs to 16 bits wide in order to prevent the bitmap growing to
absurd sizes if any future CPU does implement 32 bit MMIDs as the
architecture manuals suggest is recommended.

When MMIDs are in use we also make use of GINVT instruction which is
available due to the global nature of MMIDs. By executing a sequence of
GINVT & SYNC 0x14 instructions we can avoid the overhead of an IPI to
each remote CPU in many cases. One complication is that GINVT will
invalidate wired entries (in all cases apart from type 0, which targets
the entire TLB). In order to avoid GINVT invalidating any wired TLB
entries we set up, we make sure to create those entries using a reserved
MMID (0) that we never associate with any address space.

Also of note is that KVM will require further work in order to support
MMIDs & GINVT, since KVM is involved in allocating IDs for guests & in
configuring the MMU. That work is not part of this patch, so for now
when MMIDs are in use KVM is disabled.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
2019-02-04 10:56:41 -08:00
Paul Burton 0b317c389c MIPS: mm: Add set_cpu_context() for ASID assignments
When we gain MMID support we'll be storing MMIDs as atomic64_t values
and accessing them via atomic64_* functions. This necessitates that we
don't use cpu_context() as the left hand side of an assignment, ie. as a
modifiable lvalue. In preparation for this introduce a new
set_cpu_context() function & replace all assignments with cpu_context()
on their left hand side with an equivalent call to set_cpu_context().

To enforce that cpu_context() should not be used for assignments, we
rewrite it as a static inline function.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
2019-02-04 10:56:33 -08:00
Paul Burton 558ec8ad71 MIPS: mm: Remove local_flush_tlb_mm()
All 3 variants of local_flush_tlb_mm() are now effectively simple calls
to drop_mmu_context(). Remove them and use drop_mmu_context() directly.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
2019-02-04 10:56:24 -08:00
Linus Torvalds 892204e06c Merge tag 'mips_4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/mips
Pull MIPS updates from James Hogan:
 "These are the main MIPS changes for 4.15.

  Fixes:
   - ralink: Fix MT7620 PCI build issues (4.5)
   - Disable cmpxchg64() and HAVE_VIRT_CPU_ACCOUNTING_GEN for 32-bit SMP
     (4.1)
   - Fix MIPS64 FP save/restore on 32-bit kernels (4.0)
   - ptrace: Pick up ptrace/seccomp changed syscall numbers (3.19)
   - ralink: Fix MT7628 pinmux (3.19)
   - BCM47XX: Fix LED inversion on WRT54GSv1 (3.17)
   - Fix n32 core dumping as o32 since regset support (3.13)
   - ralink: Drop obsolete USB_ARCH_HAS_HCD select

  Build system:
   - Default to "generic" (multiplatform) system type instead of IP22
   - Use generic little endian MIPS32 r2 configuration as default
     defconfig instead of ip22_defconfig

  FPU emulation:
   - Fix exception generation for certain R6 FPU instructions

  SMP:
   - Allow __cpu_number_map to be larger than NR_CPUS for sparse CPU id
     spaces

  Miscellaneous:
   - Add iomem resource for kernel bss section for kexec/kdump
   - Atomics: Nudge writes on bit unlock
   - DT files: Standardise "ok" -> "okay"

  Minor cleanups:
   - Define virt_to_pfn()
   - Make thread_saved_pc static
   - Simplify 32-bit sign extension in __read_64bit_c0_split()
   - DMA: Use vma_pages() helper
   - FPU emulation: Replace unsigned with unsigned int
   - MM: Removed unused lastpfn
   - Alchemy: Make clk_ops const
   - Lasat: Use setup_timer() helper
   - ralink: Use BIT() in MT7620 PCI driver

  Platform support:

  BMIPS:
  - Enable HARDIRQS_SW_RESEND

  Broadcom BCM63XX:
  - Add clkdev lookup support
  - Update clk driver, UART driver, DTs to handle named refclk from DTs
  - Split apart various clocks to more closely match hardware
  - Add ethernet clocks

  Cavium Octeon:
  - Remove usage of cvmx_wait() in favour of __delay()

  ImgTec Pistachio:
  - DT: Drop deprecated dwmmc num-slots property

  Ingenic JZ4780:
  - Add NFS root to Ci20 defconfig
  - Add watchdog to Ci20 DT & defconfig, and allow building of watchdog
    driver with this SoC

  Generic (multiplatform):
  - Migrate xilfpga (MIPSfpga) platform to the generic platform

  Lantiq xway:
  - Fix ASC0/ASC1 clocks"

* tag 'mips_4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/mips: (46 commits)
  MIPS: Add iomem resource for kernel bss section.
  MIPS: cmpxchg64() and HAVE_VIRT_CPU_ACCOUNTING_GEN don't work for 32-bit SMP
  MIPS: BMIPS: Enable HARDIRQS_SW_RESEND
  MIPS: pci: Make use of the BIT() macro inside the mt7620 driver
  MIPS: pci: Remove KERN_WARN instance inside the mt7620 driver
  MIPS: pci: Remove duplicate define in mt7620 driver
  MIPS: ralink: Fix typo in mt7628 pinmux function
  MIPS: ralink: Fix MT7628 pinmux
  MIPS: Fix odd fp register warnings with MIPS64r2
  watchdog: jz4780: Allow selection of jz4740-wdt driver
  MIPS/ptrace: Update syscall nr on register changes
  MIPS/ptrace: Pick up ptrace/seccomp changed syscalls
  MIPS: Fix an n32 core file generation regset support regression
  MIPS: Fix MIPS64 FP save/restore on 32-bit kernels
  MIPS: page.h: Define virt_to_pfn()
  MIPS: Xilfpga: Switch to using generic defconfigs
  MIPS: generic: Add support for MIPSfpga
  MIPS: Set defconfig target to a generic system for 32r2el
  MIPS: Kconfig: Set default MIPS system type as generic
  MIPS: DTS: Remove num-slots from Pistachio SoC
  ...
2017-11-15 11:36:08 -08:00