linux-toradex.git/arch/mips/kernel/smp-cps.c, branch v5.8

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

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 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Allison Randal 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman

MIPS: kexec: CPS systems to halt nonboot CPUs

2018-09-22T17:32:33+00:00

Share code between play_dead() and cps_kexec_nonboot_cpu(). Register the
latter to mp_ops for kexec.

Signed-off-by: Dengcheng Zhu 
Signed-off-by: Paul Burton 
Patchwork: https://patchwork.linux-mips.org/patch/20567/
Cc: pburton@wavecomp.com
Cc: ralf@linux-mips.org
Cc: linux-mips@linux-mips.org
Cc: rachel.mozes@intel.com

MIPS: SMP-CPS: Remove duplicate assignment of core in play_dead

2018-02-05T14:36:06+00:00

The merge of commit f875a832d2028 ("MIPS: Abstract CPU core & VP(E) ID
access through accessor functions") ended up creating a duplicate
assignment of core during the rebase on commit bac06cf0fb9d ("MIPS:
smp-cps: Fix potentially uninitialised value of core"). Remove the
duplicate.

Fixes: f875a832d202 ("MIPS: Abstract CPU core & VP(E) ID access through accessor functions")
Signed-off-by: Matt Redfearn 
Cc: Ralf Baechle 
Cc: Paul Burton 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17955/
Signed-off-by: James Hogan

MIPS: CPS: Fix use of current_cpu_data in preemptible code

2017-11-01T21:05:57+00:00

Commit 1ec9dd80bedc ("MIPS: CPS: Detect CPUs in secondary clusters")
added a check in cps_boot_secondary() that the secondary being booted is
in the same cluster as the CPU running this code. This check is
performed using current_cpu_data without disabling preemption. As such
when CONFIG_PREEMPT=y, a BUG is triggered:

[   57.991693] BUG: using smp_processor_id() in preemptible [00000000] code: hotplug/1749

[   58.063077] Call Trace:
[   58.065842] [<8040cdb4>] show_stack+0x84/0x114
[   58.070830] [<80b11b38>] dump_stack+0xf8/0x140
[   58.075796] [<8079b12c>] check_preemption_disabled+0xec/0x118
[   58.082204] [<80415110>] cps_boot_secondary+0x84/0x44c
[   58.087935] [<80413a14>] __cpu_up+0x34/0x98
[   58.092624] [<80434240>] bringup_cpu+0x38/0x114
[   58.097680] [<80434af0>] cpuhp_invoke_callback+0x168/0x8f0
[   58.103801] [<804362d0>] _cpu_up+0x154/0x1c8
[   58.108565] [<804363dc>] do_cpu_up+0x98/0xa8
[   58.113333] [<808261f8>] device_online+0x84/0xc0
[   58.118481] [<80826294>] online_store+0x60/0x98
[   58.123562] [<8062261c>] kernfs_fop_write+0x158/0x1d4
[   58.129196] [<805a2ae4>] __vfs_write+0x4c/0x168
[   58.134247] [<805a2dc8>] vfs_write+0xe0/0x190
[   58.139095] [<805a2fe0>] SyS_write+0x68/0xc4
[   58.143854] [<80415d58>] syscall_common+0x34/0x58

In reality we don't currently support running the kernel on CPUs not in
cluster 0, so the answer to cpu_cluster(¤t_cpu_data) will always
be 0, even if this task being preempted and continues running on a
different CPU. Regardless, the BUG should not be triggered, so fix this
by switching to raw_current_cpu_data. When multicluster support lands
upstream this check will need removing or changing anyway.

Fixes: 1ec9dd80bedc ("MIPS: CPS: Detect CPUs in secondary clusters")
Signed-off-by: Matt Redfearn 
Reviewed-by: Paul Burton 
CC: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17563/
Signed-off-by: James Hogan

Update MIPS email addresses

2017-10-31T22:42:39+00:00

MIPS will soon not be a part of Imagination Technologies, and as such
many @imgtec.com email addresses will no longer be valid. This patch
updates the addresses for those who:

 - Have 10 or more patches in mainline authored using an @imgtec.com
   email address, or any patches dated within the past year.

 - Are still with Imagination but leaving as part of the MIPS business
   unit, as determined from an internal email address list.

 - Haven't already updated their email address (ie. JamesH) or expressed
   a desire to be excluded (ie. Maciej).

 - Acked v2 or earlier of this patch, which leaves Deng-Cheng, Matt &
   myself.

New addresses are of the form firstname.lastname@mips.com, and all
verified against an internal email address list. An entry is added to
.mailmap for each person such that get_maintainer.pl will report the new
addresses rather than @imgtec.com addresses which will soon be dead.

Instances of the affected addresses throughout the tree are then
mechanically replaced with the new @mips.com address.

Signed-off-by: Paul Burton 
Cc: Deng-Cheng Zhu 
Cc: Deng-Cheng Zhu 
Acked-by: Dengcheng Zhu 
Cc: Matt Redfearn 
Cc: Matt Redfearn 
Acked-by: Matt Redfearn 
Cc: Andrew Morton 
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: trivial@kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17540/
Signed-off-by: James Hogan

MIPS: Remove unnecessary inclusions of linux/irqchip/mips-gic.h

2017-09-04T11:53:14+00:00

linux/irqchip/mips-gic.h is included in a few files that don't actually
use it at all. Remove these unnecessary inclusions in preparation for
removing the header.

Signed-off-by: Paul Burton 
Cc: Jason Cooper 
Cc: Marc Zyngier 
Cc: Thomas Gleixner 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17048/
Signed-off-by: Ralf Baechle

MIPS: CPS: Read GIC_VL_IDENT directly, not via irqchip driver

2017-09-04T11:53:14+00:00

Rather than calling the gic_read_local_vp_id() function from the GIC
irqchip driver, call read_gic_vl_ident() to read the GIC_VL_IDENT
register directly. This will allow us to remove gic_read_local_vp_id()
from the irqchip driver in a further patch, since that driver doesn't
actually care about the register's value.

Signed-off-by: Paul Burton 
Cc: Jason Cooper 
Cc: Marc Zyngier 
Cc: Thomas Gleixner 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17023/
Signed-off-by: Ralf Baechle

MIPS: CPS: Detect CPUs in secondary clusters

2017-08-29T22:57:28+00:00

As a first step towards supporting multi-cluster systems, detect cores &
VPs in secondary clusters & record their cluster information in the
cpu_data array. The "VP topology" line printed during boot is extended
to display multiple clusters. On a single cluster it shows output like
the following:

  VP topology: {4,4}

This would indicate a system with 2 cores which each contain 4 VPs. We
extend this to cover multiple clusters in a natural way:

  VP topology: {4,4},{2,2}

This would indicate a system with 2 clusters. The first cluster contains
2 cores which each contain 4 VPs. The second cluster contains 2 cores
which each contain 2 VPs.

Actually booting these cores & VPs is left to further patches once other
pieces are in place.

Signed-off-by: Paul Burton 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17017/
Signed-off-by: Ralf Baechle

MIPS: CPS: Cluster support for topology functions

2017-08-29T22:57:28+00:00

Modify the functions we use to read information about the topology of
the system (the number of cores, VPs & IOCUs that it contains) in order
to take into account multiple clusters, and provide a new function to
determine the number of clusters in the system.

Users of these functions are modified only such that they continue to
build successfully - having them actually handle multiple clusters is
left to further patches.

Signed-off-by: Paul Burton 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17016/
Patchwork: https://patchwork.linux-mips.org/patch/17218/
Signed-off-by: Ralf Baechle

MIPS: CPS: Have asm/mips-cps.h include CM & CPC headers

2017-08-29T22:57:27+00:00

With Coherence Manager (CM) 3.5 information about the topology of the
system, which has previously only been available through & accessed from
the CM, is now also provided by the Cluster Power Controller (CPC). This
includes a new CPC_CONFIG register mirroring GCR_CONFIG, and similarly a
new CPC_Cx_CONFIG register mirroring GCR_Cx_CONFIG.

In preparation for adjusting functions such as mips_cm_numcores(), which
have previously only needed to access the CM, to also access the CPC
this patch modifies the way we use the various CPS headers. Rather than
having users include asm/mips-cm.h or asm/mips-cpc.h individually we
instead have users include asm/mips-cps.h which in turn includes
asm/mips-cm.h & asm/mips-cpc.h. This means that users will gain access
to both CM & CPC registers by including one header, and most importantly
it makes asm/mips-cps.h an ideal location for helper functions which
need to access the various components of the CPS.

Signed-off-by: Paul Burton 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17015/
Patchwork: https://patchwork.linux-mips.org/patch/17217/
Signed-off-by: Ralf Baechle