linux.git/arch/parisc/kernel/setup.c, branch v6.0

Revert "parisc: Mark sched_clock unstable only if clocks are not syncronized"

2022-05-08T18:01:11+00:00

This reverts commit d97180ad68bdb7ee10f327205a649bc2f558741d.

It triggers RCU stalls at boot with a 32-bit kernel.

Signed-off-by: Helge Deller 
Noticed-by: John David Anglin 
Cc: stable@vger.kernel.org # v5.15+

parisc: Autodetect default output device and set console= kernel parameter

2022-01-20T19:39:19+00:00

Usually palo (the PA-RISC boot loader) will check at boot time if the
machine/firmware was configured to use the serial line (ttyS0, SERIAL_x)
or the graphical display (tty0, graph) as default output device and add
the correct "console=ttyS0" or "console=tty0" Linux kernel parameter to
the kernel command line when starting the Linux kernel.

But the kernel could also have been started via the HP-UX boot loader
or directly in qemu, in which cases the console parameter is missing.

This patch fixes this problem by adding the correct console= parameter
if it's missing in the current kernel command line.

Signed-off-by: Helge Deller

parisc: Use safer strscpy() in setup_cmdline()

2022-01-20T19:39:19+00:00

Signed-off-by: Helge Deller

parisc: Mark sched_clock unstable only if clocks are not syncronized

2021-09-09T10:44:31+00:00

We check at runtime if the cr16 clocks are stable across CPUs. Only mark
the sched_clock unstable by calling clear_sched_clock_stable() if we
know that we run on a system which isn't syncronized across CPUs.

Signed-off-by: Helge Deller

parisc: Fix typo in setup.c

2021-05-03T13:08:59+00:00

Signed-off-by: Helge Deller

arch/parisc/setup: Drop dummy_con initialization

2020-01-14T14:29:17+00:00

con_init in tty/vt.c will now set conswitchp to dummy_con if it's unset.
Drop it from arch setup code.

Signed-off-by: Arvind Sankar 
Link: https://lore.kernel.org/r/20191218214506.49252-17-nivedita@alum.mit.edu
Signed-off-by: Greg Kroah-Hartman

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 153

2019-05-30T18:26:32+00:00

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 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 675 mass ave cambridge
  ma 02139 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 77 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Allison Randal 
Reviewed-by: Armijn Hemel 
Reviewed-by: Richard Fontana 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.837555891@linutronix.de
Signed-off-by: Greg Kroah-Hartman

parisc: Use per-pagetable spinlock

2019-05-03T21:47:41+00:00

PA-RISC uses a global spinlock to protect pagetable updates in the TLB
fault handlers. When multiple cores are taking TLB faults simultaneously,
the cache line containing the spinlock becomes a bottleneck.

This patch embeds the spinlock in the top level page directory, so that
every process has its own lock. It improves performance by 30% when
doing parallel compilations.

At least on the N class systems, only one PxTLB inter processor
broadcast can be active at any one time on the Merced bus. If a Merced
bus is found, this patch serializes the TLB flushes with the
pa_tlb_flush_lock spinlock.

v1: Initial patch by Mikulas
v2: Added Merced detection by Helge
v3: Revised TLB serialization by Dave & Helge

Signed-off-by: Mikulas Patocka 
Signed-off-by: John David Anglin 
Signed-off-by: Helge Deller

parisc: Detect QEMU earlier in boot process

2019-04-06T17:07:55+00:00

While adding LASI support to QEMU, I noticed that the QEMU detection in
the kernel happens much too late. For example, when a LASI chip is found
by the kernel, it registers the LASI LED driver as well.  But when we
run on QEMU it makes sense to avoid spending unnecessary CPU cycles, so
we need to access the running_on_QEMU flag earlier than before.

This patch now makes the QEMU detection the fist task of the Linux
kernel by moving it to where the kernel enters the C-coding.

Fixes: 310d82784fb4 ("parisc: qemu idle sleep support")
Signed-off-by: Helge Deller 
Cc: stable@vger.kernel.org # v4.14+

parisc: don't include in

2019-02-21T19:37:11+00:00

No need for any of the definitions here, all there real work now
happens out of line.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Helge Deller