Commit Graph

58 Commits

Author SHA1 Message Date
Sebastian Andrzej Siewior
95ac706744 ACPI: processor: Replace deprecated CPU-hotplug functions
The functions cpu_hotplug_begin, cpu_hotplug_done, get_online_cpus() and
put_online_cpus() have been deprecated during the CPU hotplug rework. They map
directly to cpus_write_lock(), cpus_write_unlock, cpus_read_lock() and
cpus_read_unlock().

Replace deprecated CPU-hotplug functions with the official version.
The behavior remains unchanged.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-08-04 20:25:54 +02:00
Rafael J. Wysocki
b6237f61fc Merge branch 'acpi-misc'
* acpi-misc:
  ACPI: dock: fix some coding style issues
  ACPI: sysfs: fix some coding style issues
  ACPI: PM: add a missed blank line after declarations
  ACPI: custom_method: fix a coding style issue
  ACPI: CPPC: fix some coding style issues
  ACPI: button: fix some coding style issues
  ACPI: battery: fix some coding style issues
  ACPI: acpi_pad: add a missed blank line after declarations
  ACPI: LPSS: add a missed blank line after declarations
  ACPI: ipmi: remove useless return statement for void function
  ACPI: processor: fix some coding style issues
  ACPI: APD: fix a block comment align issue
  ACPI: AC: fix some coding style issues
  ACPI: fix various typos in comments
2021-04-26 17:04:41 +02:00
Xiaofei Tan
c8deb1c257 ACPI: processor: fix some coding style issues
Fix some coding style issues reported by checkpatch.pl, including the
following types:

ERROR: code indent should use tabs where possible
WARNING: Block comments use a trailing */ on a separate line
WARNING: Missing a blank line after declarations
WARNING: labels should not be indented

Signed-off-by: Xiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-04-08 16:27:02 +02:00
Rafael J. Wysocki
52af99c3f5 ACPI: processor: Get rid of ACPICA message printing
The ACPI_DEBUG_PRINT() and ACPI_EXCEPTION() macros are used for
message printing in the ACPICA code and they should not be used
elsewhere.  Special configuration (either kernel command line or
sysfs-based) is needed to see the messages printed by them and
the format of those messages is also special and convoluted.

For this reason, replace all of the ACPI_DEBUG_PRINT() and
ACPI_EXCEPTION() instances in the ACPI processor driver with
corresponding dev_*(), acpi_handle_*() and pr_*() calls depending
on the context in which they appear.

Also drop the ACPI_PROCESSOR_COMPONENT definition that is not going
to be necessary any more.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
2021-03-08 16:51:19 +01:00
Alex Hung
d85cc6635a ACPI: processor: remove comment regarding string _UID support
ACPI 6.3 Errata A no longer allows _UID to return a string except for
Itanium (for historical reasons) as stated in section 5.2.12:

"From ACPI Specification 6.3 onward, all processor objects for all
architectures except Itanium must now use Device() objects with an
_HID of ACPI0007, and use only integer _UID values."

Therefore, the "we don't handle string _UIDs yet" comment, which
implies a missing feature, is redundant, so drop it.

Signed-off-by: Alex Hung <alex.hung@canonical.com>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-10-16 18:11:27 +02:00
Chen Yu
653f68b6ec ACPI: processor: Print more information when acpi_processor_evaluate_cst() fails
Some platforms have bogus _CST which might cause unexpectd behavior
in the CPU idle driver. Some bogus _CST might be unable to be
disassembled by acpica-tools due to broken format.

Print extra log if the _CST extraction/verification failes.

This can be used to help narrow down why the CPU idle driver fails
to behave as expected.

Suggested-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-09-21 18:24:35 +02:00
Gustavo A. R. Silva
57d2dd4bd1 ACPI: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through # [1]
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-07-09 14:09:28 +02:00
Rafael J. Wysocki
77fb4e0a55 ACPI: processor: Export acpi_processor_evaluate_cst()
The intel_idle driver will be modified to use ACPI _CST subsequently
and it will need to call acpi_processor_evaluate_cst(), so move that
function to acpi_processor.c so that it is always present (which is
required by intel_idle) and export it to modules to allow the ACPI
processor driver (which is modular) to call it.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-12-27 11:02:07 +01:00
Rafael J. Wysocki
bc94638886 ACPI: processor: Export function to claim _CST control
The intel_idle driver will be modified to use ACPI _CST subsequently
and it will need to notify the platform firmware of that if
acpi_gbl_FADT.cst_control is set, so add a routine for this purpose,
acpi_processor_claim_cst_control(), to acpi_processor.c (so that it
is always present which is required by intel_idle) and export it
to allow the ACPI processor driver (which is modular) to call it.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-12-16 12:06:18 +01:00
Jiri Slaby
2c2b005f54 ACPI / processor: don't print errors for processorIDs == 0xff
Some platforms define their processors in this manner:
    Device (SCK0)
    {
	Name (_HID, "ACPI0004" /* Module Device */)  // _HID: Hardware ID
	Name (_UID, "CPUSCK0")  // _UID: Unique ID
	Processor (CP00, 0x00, 0x00000410, 0x06){}
	Processor (CP01, 0x02, 0x00000410, 0x06){}
	Processor (CP02, 0x04, 0x00000410, 0x06){}
	Processor (CP03, 0x06, 0x00000410, 0x06){}
	Processor (CP04, 0x01, 0x00000410, 0x06){}
	Processor (CP05, 0x03, 0x00000410, 0x06){}
	Processor (CP06, 0x05, 0x00000410, 0x06){}
	Processor (CP07, 0x07, 0x00000410, 0x06){}
	Processor (CP08, 0xFF, 0x00000410, 0x06){}
	Processor (CP09, 0xFF, 0x00000410, 0x06){}
	Processor (CP0A, 0xFF, 0x00000410, 0x06){}
	Processor (CP0B, 0xFF, 0x00000410, 0x06){}
...

The processors marked as 0xff are invalid, there are only 8 of them in
this case.

So do not print an error on ids == 0xff, just print an info message.
Actually, we could return ENODEV even on the first CPU with ID 0xff, but
ACPI spec does not forbid the 0xff value to be a processor ID. Given
0xff could be a correct one, we would break working systems if we
returned ENODEV.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-08-09 10:48:34 +02:00
Thomas Gleixner
d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
Based on 2 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 version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:55 +02:00
Dou Liyang
d0381bf4f8 ACPI / processor: Fix the return value of acpi_processor_ids_walk()
ACPI driver should make sure all the processor IDs in their ACPI Namespace
are unique. the driver performs a depth-first walk of the namespace tree
and calls the acpi_processor_ids_walk() to check the duplicate IDs.

But, the acpi_processor_ids_walk() mistakes the return value. If a
processor is checked, it returns true which causes the walk break
immediately, and other processors will never be checked.

Repace the value with AE_OK which is the standard acpi_status value.
And don't abort the namespace walk even on error.

Fixes: 8c8cb30f49 (acpi/processor: Implement DEVICE operator for processor enumeration)
Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-10-04 08:58:32 +02:00
Gustavo A. R. Silva
1be9c3a0a0 ACPI: Mark expected switch fall-throughs
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-11-09 00:55:16 +01:00
Colin Ian King
0ed780e316 ACPI / processor: make function acpi_processor_check_duplicates() static
The function acpi_processor_check_duplicates() is local to the source
and does not need to be in global scope, so make it static.

Cleans up sparse warnings:
symbol 'acpi_processor_check_duplicates' was not declared. Should it
be static?

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-24 03:25:47 +02:00
Prakash, Prashanth
35b6873598 ACPI / Processor: Drop setup_max_cpus check from acpi_processor_add()
When maxcpus=X kernel argument is used, we parse the ACPI tables only
for the first X cpus. The per-cpu ACPI data include the _PSD tables
which gives information about related cpus.

cppc_cpufreq and acpi-cpufreq parses the table once during init to
deduce the related cpus. If a user brings a new cpu online after boot
the related cpu data becomes incorrect.

acpi_get_psd_map() in acpi_cppc.c returns error if it fails to find
the parsed ACPI data for possible CPU resulting in cppc_cpufreq
initialization failure.

With this change we will probe all possible CPUs prior to cpufreq
initialization, but will bring only setup_max_cpus online. nr_cpus
kernel parameter can be used to restict even parsing per-cpu ACPI
tables.

Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org>
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-04-18 16:50:24 +02:00
Dou Liyang
a77d6cd968 acpi/processor: Check for duplicate processor ids at hotplug time
The check for duplicate processor ids happens at boot time based on the
ACPI table contents, but the final sanity checks for a processor happen
at hotplug time.

At hotplug time, where the physical information is available, which might
differ from the ACPI table information, a check for duplicate processor
ids is missing.

Add it to the hotplug checks and rename the function so it better
reflects its purpose.

Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Tested-by: Xiaolong Ye <xiaolong.ye@intel.com>
Cc: rjw@rjwysocki.net
Cc: linux-acpi@vger.kernel.org
Cc: guzheng1@huawei.com
Cc: izumi.taku@jp.fujitsu.com
Cc: lenb@kernel.org
Link: http://lkml.kernel.org/r/1488528147-2279-6-git-send-email-douly.fnst@cn.fujitsu.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-11 14:41:20 +01:00
Dou Liyang
8c8cb30f49 acpi/processor: Implement DEVICE operator for processor enumeration
ACPI allows to declare processors either with the PROCESSOR or with the
DEVICE operator. The current implementation handles only the PROCESSOR
operator.

On a system which uses the DEVICE operator for processor enumeration the
evaluation fails.

Check for the ACPI type of the ACPI handle and evaluate PROCESSOR and
DEVICE types separately.

Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Tested-by: Xiaolong Ye <xiaolong.ye@intel.com>
Cc: rjw@rjwysocki.net
Cc: linux-acpi@vger.kernel.org
Cc: guzheng1@huawei.com
Cc: izumi.taku@jp.fujitsu.com
Cc: lenb@kernel.org
Link: http://lkml.kernel.org/r/1488528147-2279-5-git-send-email-douly.fnst@cn.fujitsu.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-11 14:41:20 +01:00
Dou Liyang
c962cff17d Revert "x86/acpi: Set persistent cpuid <-> nodeid mapping when booting"
Revert: dc6db24d24 ("x86/acpi: Set persistent cpuid <-> nodeid mapping when booting")

The mapping of "cpuid <-> nodeid" is established at boot time via ACPI
tables to keep associations of workqueues and other node related items
consistent across cpu hotplug.

But, ACPI tables are unreliable and failures with that boot time mapping
have been reported on machines where the ACPI table and the physical
information which is retrieved at actual hotplug is inconsistent.

Revert the mapping implementation so it can be replaced with a less error
prone approach.

Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Tested-by: Xiaolong Ye <xiaolong.ye@intel.com>
Cc: rjw@rjwysocki.net
Cc: linux-acpi@vger.kernel.org
Cc: guzheng1@huawei.com
Cc: izumi.taku@jp.fujitsu.com
Cc: lenb@kernel.org
Link: http://lkml.kernel.org/r/1488528147-2279-2-git-send-email-douly.fnst@cn.fujitsu.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-11 14:41:18 +01:00
Vitaly Kuznetsov
febf240741 x86/ACPI: keep x86_cpu_to_acpiid mapping valid on CPU hotplug
We may or may not have all possible CPUs in MADT on boot but in any
case we're overwriting x86_cpu_to_acpiid mapping with U32_MAX when
acpi_register_lapic() is called again on the CPU hotplug path:

acpi_processor_hotadd_init()
  -> acpi_map_cpu()
    -> acpi_register_lapic()

As we have the required acpi_id information in acpi_processor_hotadd_init()
propagate it to acpi_map_cpu() to always keep x86_cpu_to_acpiid
mapping valid.

Reported-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-02-07 13:34:56 +01:00
Dou Liyang
fd74da217d acpi: Validate processor id when mapping the processor
When we want to identify whether the proc_id is unreasonable or not, we
can call the "acpi_processor_validate_proc_id" function. It will search
in the duplicate IDs. If we find the proc_id in the IDs, we return true
to the call function. Conversely, the false represents available.

When we establish all possible cpuid <-> nodeid mapping to handle the
cpu hotplugs, we will use the proc_id from ACPI table.

We do validation when we get the proc_id. If the result is true, we
will stop the mapping.

[ tglx: Mark the new function __init ]

Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: mika.j.penttila@gmail.com
Cc: len.brown@intel.com
Cc: rafael@kernel.org
Cc: rjw@rjwysocki.net
Cc: yasu.isimatu@gmail.com
Cc: linux-mm@kvack.org
Cc: linux-acpi@vger.kernel.org
Cc: isimatu.yasuaki@jp.fujitsu.com
Cc: gongzhaogang@inspur.com
Cc: tj@kernel.org
Cc: izumi.taku@jp.fujitsu.com
Cc: cl@linux.com
Cc: chen.tang@easystack.cn
Cc: akpm@linux-foundation.org
Cc: kamezawa.hiroyu@jp.fujitsu.com
Cc: lenb@kernel.org
Link: http://lkml.kernel.org/r/1472114120-3281-8-git-send-email-douly.fnst@cn.fujitsu.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-21 21:18:40 +02:00
Dou Liyang
8e089eaa19 acpi: Provide mechanism to validate processors in the ACPI tables
[Problem]

When we set cpuid <-> nodeid mapping to be persistent, it will use the DSDT
As we know, the ACPI tables are just like user's input in that respect, and
we don't crash if user's input is unreasonable.

Such as, the mapping of the proc_id and pxm in some machine's ACPI table is
like this:

proc_id   |    pxm
--------------------
0       <->     0
1       <->     0
2       <->     1
3       <->     1
89      <->     0
89      <->     0
89      <->     0
89      <->     1
89      <->     1
89      <->     2
89      <->     3
.....

We can't be sure which one is correct to the proc_id 89. We may map a wrong
node to a cpu. When pages are allocated, this may cause a kernal panic.

So, we should provide mechanisms to validate the ACPI tables, just like we
do validation to check user's input in web project.

The mechanism is that the processor objects which have the duplicate IDs
are not valid.

[Solution]

We add a validation function, like this:

foreach Processor in DSDT
	proc_id = get_ACPI_Processor_number(Processor)
	if (proc_id exists )
		mark both of them as being unreasonable;

The function will record the unique or duplicate processor IDs.

The duplicate processor IDs such as 89 are regarded as the unreasonable IDs
which mean that the processor objects in question are not valid.

[ tglx: Add __init[data] annotations ]

Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: mika.j.penttila@gmail.com
Cc: len.brown@intel.com
Cc: rafael@kernel.org
Cc: rjw@rjwysocki.net
Cc: yasu.isimatu@gmail.com
Cc: linux-mm@kvack.org
Cc: linux-acpi@vger.kernel.org
Cc: isimatu.yasuaki@jp.fujitsu.com
Cc: gongzhaogang@inspur.com
Cc: tj@kernel.org
Cc: izumi.taku@jp.fujitsu.com
Cc: cl@linux.com
Cc: chen.tang@easystack.cn
Cc: akpm@linux-foundation.org
Cc: kamezawa.hiroyu@jp.fujitsu.com
Cc: lenb@kernel.org
Link: http://lkml.kernel.org/r/1472114120-3281-7-git-send-email-douly.fnst@cn.fujitsu.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-21 21:18:39 +02:00
Gu Zheng
dc6db24d24 x86/acpi: Set persistent cpuid <-> nodeid mapping when booting
The whole patch-set aims at making cpuid <-> nodeid mapping persistent. So that,
when node online/offline happens, cache based on cpuid <-> nodeid mapping such as
wq_numa_possible_cpumask will not cause any problem.
It contains 4 steps:
1. Enable apic registeration flow to handle both enabled and disabled cpus.
2. Introduce a new array storing all possible cpuid <-> apicid mapping.
3. Enable _MAT and MADT relative apis to return non-present or disabled cpus' apicid.
4. Establish all possible cpuid <-> nodeid mapping.

This patch finishes step 4.

This patch set the persistent cpuid <-> nodeid mapping for all enabled/disabled
processors at boot time via an additional acpi namespace walk for processors.

[ tglx: Remove the unneeded exports ]

Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com>
Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: mika.j.penttila@gmail.com
Cc: len.brown@intel.com
Cc: rafael@kernel.org
Cc: rjw@rjwysocki.net
Cc: yasu.isimatu@gmail.com
Cc: linux-mm@kvack.org
Cc: linux-acpi@vger.kernel.org
Cc: isimatu.yasuaki@jp.fujitsu.com
Cc: gongzhaogang@inspur.com
Cc: tj@kernel.org
Cc: izumi.taku@jp.fujitsu.com
Cc: cl@linux.com
Cc: chen.tang@easystack.cn
Cc: akpm@linux-foundation.org
Cc: kamezawa.hiroyu@jp.fujitsu.com
Cc: lenb@kernel.org
Link: http://lkml.kernel.org/r/1472114120-3281-6-git-send-email-douly.fnst@cn.fujitsu.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-21 21:18:39 +02:00
Gu Zheng
8ad893faf2 x86/acpi: Enable MADT APIs to return disabled apicids
The whole patch-set aims at making cpuid <-> nodeid mapping persistent. So that,
when node online/offline happens, cache based on cpuid <-> nodeid mapping such as
wq_numa_possible_cpumask will not cause any problem.
It contains 4 steps:
1. Enable apic registeration flow to handle both enabled and disabled cpus.
2. Introduce a new array storing all possible cpuid <-> apicid mapping.
3. Enable _MAT and MADT relative apis to return non-present or disabled cpus' apicid.
4. Establish all possible cpuid <-> nodeid mapping.

This patch finishes step 3.

There are four mappings in the kernel:
1. nodeid (logical node id)   <->   pxm        (persistent)
2. apicid (physical cpu id)   <->   nodeid     (persistent)
3. cpuid (logical cpu id)     <->   apicid     (not persistent, now persistent by step 2)
4. cpuid (logical cpu id)     <->   nodeid     (not persistent)

So, in order to setup persistent cpuid <-> nodeid mapping for all possible CPUs,
we should:
1. Setup cpuid <-> apicid mapping for all possible CPUs, which has been done in step 1, 2.
2. Setup cpuid <-> nodeid mapping for all possible CPUs. But before that, we should
   obtain all apicids from MADT.

All processors' apicids can be obtained by _MAT method or from MADT in ACPI.
The current code ignores disabled processors and returns -ENODEV.

After this patch, a new parameter will be added to MADT APIs so that caller
is able to control if disabled processors are ignored.

Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com>
Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: mika.j.penttila@gmail.com
Cc: len.brown@intel.com
Cc: rafael@kernel.org
Cc: rjw@rjwysocki.net
Cc: yasu.isimatu@gmail.com
Cc: linux-mm@kvack.org
Cc: linux-acpi@vger.kernel.org
Cc: isimatu.yasuaki@jp.fujitsu.com
Cc: gongzhaogang@inspur.com
Cc: tj@kernel.org
Cc: izumi.taku@jp.fujitsu.com
Cc: cl@linux.com
Cc: chen.tang@easystack.cn
Cc: akpm@linux-foundation.org
Cc: kamezawa.hiroyu@jp.fujitsu.com
Cc: lenb@kernel.org
Link: http://lkml.kernel.org/r/1472114120-3281-5-git-send-email-douly.fnst@cn.fujitsu.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-21 21:18:39 +02:00
Rafael J. Wysocki
86314751c7 ACPI / processor: Avoid reserving IO regions too early
Roland Dreier reports that one of his systems cannot boot because of
the changes made by commit ac212b6980 (ACPI / processor: Use common
hotplug infrastructure).

The problematic part of it is the request_region() call in
acpi_processor_get_info() that used to run at module init time before
the above commit and now it runs much earlier.  Unfortunately, the
region(s) reserved by it fall into a range the PCI subsystem attempts
to reserve for AHCI IO BARs.  As a result, the PCI reservation fails
and AHCI doesn't work, while previously the PCI reservation would
be made before acpi_processor_get_info() and it would succeed.

That request_region() call, however, was overlooked by commit
ac212b6980, as it is not necessary for the enumeration of the
processors.  It only is needed when the ACPI processor driver
actually attempts to handle them which doesn't happen before
loading the ACPI processor driver module.  Therefore that call
should have been moved from acpi_processor_get_info() into that
module.

Address the problem by moving the request_region() call in question
out of acpi_processor_get_info() and use the observation that the
region reserved by it is only needed if the FADT-based CPU
throttling method is going to be used, which means that it should
be sufficient to invoke it from acpi_processor_get_throttling_fadt().

Fixes: ac212b6980 (ACPI / processor: Use common hotplug infrastructure)
Reported-by: Roland Dreier <roland@purestorage.com>
Tested-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-02 01:57:50 +02:00
Srinivas Pandruvada
a21211672c ACPI / processor: Request native thermal interrupt handling via _OSC
There are several reports of freeze on enabling HWP (Hardware PStates)
feature on Skylake-based systems by the Intel P-states driver. The root
cause is identified as the HWP interrupts causing BIOS code to freeze.

HWP interrupts use the thermal LVT which can be handled by Linux
natively, but on the affected Skylake-based systems SMM will respond
to it by default.  This is a problem for several reasons:
 - On the affected systems the SMM thermal LVT handler is broken (it
   will crash when invoked) and a BIOS update is necessary to fix it.
 - With thermal interrupt handled in SMM we lose all of the reporting
   features of the arch/x86/kernel/cpu/mcheck/therm_throt driver.
 - Some thermal drivers like x86-package-temp depend on the thermal
   threshold interrupts signaled via the thermal LVT.
 - The HWP interrupts are useful for debugging and tuning
   performance (if the kernel can handle them).
The native handling of thermal interrupts needs to be enabled
because of that.

This requires some way to tell SMM that the OS can handle thermal
interrupts.  That can be done by using _OSC/_PDC in processor
scope very early during ACPI initialization.

The meaning of _OSC/_PDC bit 12 in processor scope is whether or
not the OS supports native handling of interrupts for Collaborative
Processor Performance Control (CPPC) notifications.  Since on
HWP-capable systems CPPC is a firmware interface to HWP, setting
this bit effectively tells the firmware that the OS will handle
thermal interrupts natively going forward.

For details on _OSC/_PDC refer to:
http://www.intel.com/content/www/us/en/standards/processor-vendor-specific-acpi-specification.html

To implement the _OSC/_PDC handshake as described, introduce a new
function, acpi_early_processor_osc(), that walks the ACPI
namespace looking for ACPI processor objects and invokes _OSC for
them with bit 12 in the capabilities buffer set and terminates the
namespace walk on the first success.

Also modify intel_thermal_interrupt() to clear HWP status bits in
the HWP_STATUS MSR to acknowledge HWP interrupts (which prevents
them from firing continuously).

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
[ rjw: Subject & changelog, function rename ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-03-26 02:00:38 +01:00