Revert "parisc: Only list existing CPUs in cpu_possible_mask"

commit 82b143aeb169b8b55798d7d2063032e1a6ceeeb0 upstream.

This reverts commit 0921244f6f4f0d05698b953fe632a99b38907226.

It broke CPU h

Revert "parisc: Only list existing CPUs in cpu_possible_mask"

commit 82b143aeb169b8b55798d7d2063032e1a6ceeeb0 upstream.

This reverts commit 0921244f6f4f0d05698b953fe632a99b38907226.

It broke CPU hotplugging because it modifies the __cpu_possible_mask
after bootup, so that it will be different than nr_cpu_ids, which
then effictively breaks the workqueue setup code and triggers crashes
when shutting down CPUs at runtime.

Guenter was the first who noticed the wrong values in __cpu_possible_mask,
since the cpumask Kunit tests were failig.

Reverting this commit fixes both issues, but sadly brings back this
uncritical runtime warning:
register_cpu_capacity_sysctl: too early to get CPU4 device!

Signed-off-by: Helge Deller <deller@gmx.de>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lkml.org/lkml/2024/2/4/146
Link: https://lore.kernel.org/lkml/Zb0mbHlIud_bqftx@slm.duckdns.org/t/
Cc: stable@vger.kernel.org # 6.0+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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parisc: BTLB: Initialize BTLB tables at CPU startup

Initialize the BTLB entries when starting up a CPU.
Note that BTLBs are not available on 64-bit CPUs.

Signed-off-by: Helge Deller <deller@gmx.de>

parisc: Fix /proc/cpuinfo output for lscpu

The lscpu command is broken since commit cab56b51ec0e ("parisc: Fix
device names in /proc/iomem") added the PA pathname to all PA
devices, includig the CPU

parisc: Fix /proc/cpuinfo output for lscpu

The lscpu command is broken since commit cab56b51ec0e ("parisc: Fix
device names in /proc/iomem") added the PA pathname to all PA
devices, includig the CPUs.

lscpu parses /proc/cpuinfo and now believes it found different CPU
types since every CPU is listed with an unique identifier (PA
pathname).

Fix this problem by simply dropping the PA pathname when listing the
CPUs in /proc/cpuinfo. There is no need to show the pathname in this
procfs file.

Fixes: cab56b51ec0e ("parisc: Fix device names in /proc/iomem")
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org> # v4.9+

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parisc: processor: Include asm/smp.h for init_per_cpu()

Fix sparse warning that init_per_cpu() isn't declared.

Signed-off-by: Helge Deller <deller@gmx.de>

parisc: processor: Fix kdoc for init_cpu_profiler()

Signed-off-by: Helge Deller <deller@gmx.de>

parisc: Show MPE/iX model string at bootup

Some (mostly 64-bit machines) machines allow to run MPE/iX and report the MPE
model string via firmware call. Enhance the pdc_model_sysmodel() function to

parisc: Show MPE/iX model string at bootup

Some (mostly 64-bit machines) machines allow to run MPE/iX and report the MPE
model string via firmware call. Enhance the pdc_model_sysmodel() function to
report that model string.
Note that some 32-bit machines like the B160L wrongly report success for the
firmware call, so include a check to prevent showing wrong info.

Signed-off-by: Helge Deller <deller@gmx.de>

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parisc: fix a crash with multicore scheduler

With the kernel 5.18, the system will hang on boot if it is compiled with
CONFIG_SCHED_MC. The last printed message is "Brought up 1 node, 1 CPU".

The c

parisc: fix a crash with multicore scheduler

With the kernel 5.18, the system will hang on boot if it is compiled with
CONFIG_SCHED_MC. The last printed message is "Brought up 1 node, 1 CPU".

The crash happens in sd_init
tl->mask (which is cpu_coregroup_mask) returns an empty mask. This happens
because cpu_topology[0].core_sibling is empty.
Consequently, sd_span is set to an empty mask
sd_id = cpumask_first(sd_span) sets sd_id == NR_CPUS (because the mask is
empty)
sd->shared = *per_cpu_ptr(sdd->sds, sd_id); sets sd->shared to NULL
because sd_id is out of range
atomic_inc(&sd->shared->ref); crashes without printing anything

We can fix it by calling reset_cpu_topology() from init_cpu_topology() -
this will initialize the sibling masks on CPUs, so that they're not empty.

This patch also removes the variable "dualcores_found", it is useless,
because during boot, init_cpu_topology is called before
store_cpu_topology. Thus, set_sched_topology(parisc_mc_topology) is never
called. We don't need to call it at all because default_topology in
kernel/sched/topology.c contains the same items as parisc_mc_topology.

Note that we should not call store_cpu_topology() from init_per_cpu()
because it is called too early in the kernel initialization process and it
results in the message "Failure to register CPU0 device". Before this
patch, store_cpu_topology() would exit immediatelly because
cpuid_topo->core id was uninitialized and it was 0.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org # v5.18
Signed-off-by: Helge Deller <deller@gmx.de>

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parisc: Merge model and model name into one line in /proc/cpuinfo

The Linux tool "lscpu" shows the double amount of CPUs if we have
"model" and "model name" in two different lines in /proc/cpuinfo.

parisc: Merge model and model name into one line in /proc/cpuinfo

The Linux tool "lscpu" shows the double amount of CPUs if we have
"model" and "model name" in two different lines in /proc/cpuinfo.
This change combines the model and the model name into one line.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org

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parisc: Only list existing CPUs in cpu_possible_mask

The inventory knows which CPUs are in the system, so this bitmask should
be in cpu_possible_mask instead of the bitmask based on CONFIG_NR_CPUS.

parisc: Only list existing CPUs in cpu_possible_mask

The inventory knows which CPUs are in the system, so this bitmask should
be in cpu_possible_mask instead of the bitmask based on CONFIG_NR_CPUS.

Reset the cpu_possible_mask before scanning the system for CPUs, and
mark each existing CPU as possible during initialization of that CPU.

This avoids those warnings later on too:

register_cpu_capacity_sysctl: too early to get CPU4 device!

Signed-off-by: Helge Deller <deller@gmx.de>
Noticed-by: John David Anglin <dave.anglin@bell.net>

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parisc: Move CPU startup-related functions into .text section

If CONFIG_HOTPLUG_CPU is enabled, those functions will be run again
after bootup. So they need to reside in the .text section.

Signed-o

parisc: Move CPU startup-related functions into .text section

If CONFIG_HOTPLUG_CPU is enabled, those functions will be run again
after bootup. So they need to reside in the .text section.

Signed-off-by: Helge Deller <deller@gmx.de>

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parisc: Switch from GENERIC_CPU_DEVICES to GENERIC_ARCH_TOPOLOGY

Switch away from the own cpu topology code to common code which is used
by ARM64 and RISCV. That will allow us to enable CPU hotplug

parisc: Switch from GENERIC_CPU_DEVICES to GENERIC_ARCH_TOPOLOGY

Switch away from the own cpu topology code to common code which is used
by ARM64 and RISCV. That will allow us to enable CPU hotplug later on.

Signed-off-by: Helge Deller <deller@gmx.de>

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parisc: Merge model and model name into one line in /proc/cpuinfo

commit 5b89966bc96a06f6ad65f64ae4b0461918fcc9d3 upstream.

The Linux tool "lscpu" shows the double amount of CPUs if we have
"model"

parisc: Merge model and model name into one line in /proc/cpuinfo

commit 5b89966bc96a06f6ad65f64ae4b0461918fcc9d3 upstream.

The Linux tool "lscpu" shows the double amount of CPUs if we have
"model" and "model name" in two different lines in /proc/cpuinfo.
This change combines the model and the model name into one line.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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parisc: Drop loops_per_jiffy from per_cpu struct

There is no need to keep a loops_per_jiffy value per cpu. Drop it.

Signed-off-by: Helge Deller <deller@gmx.de>

parisc: Replace cpu_up/down() with add/remove_cpu()

The core device API performs extra housekeeping bits that are missing
from directly calling cpu_up/down().

See commit a6717c01ddc2 ("powerpc/rtas

parisc: Replace cpu_up/down() with add/remove_cpu()

The core device API performs extra housekeeping bits that are missing
from directly calling cpu_up/down().

See commit a6717c01ddc2 ("powerpc/rtas: use device model APIs and
serialization during LPM") for an example description of what might go
wrong.

This also prepares to make cpu_up/down() a private interface of the CPU
subsystem.

Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Helge Deller <deller@gmx.de>
Link: https://lkml.kernel.org/r/20200323135110.30522-13-qais.yousef@arm.com

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

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of th

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

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 <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.837555891@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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parisc: Use __ro_after_init in processor.c

Signed-off-by: Helge Deller <deller@gmx.de>

parisc: Show n/a if product number not available

Signed-off-by: Helge Deller <deller@gmx.de>

parisc: Show machine product number during boot

Ask PDC firmware during boot for the original and current product
number as well as the serial number and show it (if available).

Signed-off-by: Helg

parisc: Show machine product number during boot

Ask PDC firmware during boot for the original and current product
number as well as the serial number and show it (if available).

Signed-off-by: Helge Deller <deller@gmx.de>

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parisc: Add hardware description to stack traces

Signed-off-by: Helge Deller <deller@gmx.de>

parisc: Add CPU topology support

Add topology support, including multi-core scheduler support on
PA8800/PA8900 CPUs and enhanced output in /proc/cpuinfo, e.g.
lscpu now reports on a single-socket, d

parisc: Add CPU topology support

Add topology support, including multi-core scheduler support on
PA8800/PA8900 CPUs and enhanced output in /proc/cpuinfo, e.g.
lscpu now reports on a single-socket, dual-core machine:

Architecture: parisc64
CPU(s): 2
On-line CPU(s) list: 0,1
Thread(s) per core: 1
Core(s) per socket: 2
Socket(s): 1
CPU family: PA-RISC 2.0
Model name: PA8800 (Mako)

Signed-off-by: Helge Deller <deller@gmx.de>

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parisc: Move init_per_cpu() into init section

Signed-off-by: Helge Deller <deller@gmx.de>

parisc/core: Fix section mismatches

Signed-off-by: Helge Deller <deller@gmx.de>

parisc/random: Add machine specific randomness

Add some machine-specific information like values of cr16 cycle counter,
machine-specific software ID and machine model to the random generator.

Signe

parisc/random: Add machine specific randomness

Add some machine-specific information like values of cr16 cycle counter,
machine-specific software ID and machine model to the random generator.

Signed-off-by: Helge Deller <deller@gmx.de>

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parisc: Enhance detection of synchronous cr16 clocksources

The cr16 clocks of the physical PARISC CPUs are usually nonsynchronous.
Nevertheless, it seems that each CPU socket (which holds two cores)

parisc: Enhance detection of synchronous cr16 clocksources

The cr16 clocks of the physical PARISC CPUs are usually nonsynchronous.
Nevertheless, it seems that each CPU socket (which holds two cores) of
PA8800 and PA8900 CPUs (e.g. in a C8000 workstation) is fed by the same
clock source, which makes the cr16 clocks of each CPU socket syncronous.
Let's try to detect such situations and mark the cr16 clocksource stable
on single-socket and single-core machines.

Signed-off-by: Helge Deller <deller@gmx.de>

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parisc: Optimize timer interrupt function

Restructure the timer interrupt function to better cope with missed timer irqs.
Optimize the calculation when the next interrupt should happen and skip irqs

parisc: Optimize timer interrupt function

Restructure the timer interrupt function to better cope with missed timer irqs.
Optimize the calculation when the next interrupt should happen and skip irqs if
they would happen too shortly after exit of the irq function.

The update_process_times() call is done anyway at every timer irq, so we can
safely drop the prof_counter and prof_multiplier variables from the per_cpu
structure.

Signed-off-by: Helge Deller <deller@gmx.de>

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