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When amd_pstate is running, writing to scaling_min_freq and
scaling_max_freq has no effect. These values are only passed to the
policy level, but not to the platform level. This means that the
platform does not know about the frequency limits set by the user.
To fix this, update the min_perf and max_perf values at the platform
level whenever the user changes the scaling_min_freq and scaling_max_freq
values.
Fixes: ffa5096a7c ("cpufreq: amd-pstate: implement Pstate EPP support for the AMD processors")
Acked-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq_driver->fast_switch() callback expects a frequency as a return
value. amd_pstate_fast_switch() was returning the return value of
amd_pstate_update_freq(), which only indicates a success or failure.
Fix this by making amd_pstate_fast_switch() return the target_freq
when the call to amd_pstate_update_freq() is successful, and return
the current frequency from policy->cur when the call to
amd_pstate_update_freq() is unsuccessful.
Fixes: 4badf2eb1e ("cpufreq: amd-pstate: Add ->fast_switch() callback")
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Wyes Karny <wyes.karny@amd.com>
Reviewed-by: Perry Yuan <perry.yuan@amd.com>
Cc: 6.4+ <stable@vger.kernel.org> # v6.4+
Signed-off-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In commit 3666062b87 ("cpufreq: amd-pstate: move to use bus_get_dev_root()")
the "amd_pstate" attributes where moved from a dedicated kobject to the
cpu root kobject.
While the dedicated kobject expects to contain kobj_attributes the root
kobject needs device_attributes.
As the changed arguments are not used by the callbacks it works most of
the time.
However CFI will detect this issue:
[ 4947.849350] CFI failure at dev_attr_show+0x24/0x60 (target: show_status+0x0/0x70; expected type: 0x8651b1de)
...
[ 4947.849409] Call Trace:
[ 4947.849410] <TASK>
[ 4947.849411] ? __warn+0xcf/0x1c0
[ 4947.849414] ? dev_attr_show+0x24/0x60
[ 4947.849415] ? report_cfi_failure+0x4e/0x60
[ 4947.849417] ? handle_cfi_failure+0x14c/0x1d0
[ 4947.849419] ? __cfi_show_status+0x10/0x10
[ 4947.849420] ? handle_bug+0x4f/0x90
[ 4947.849421] ? exc_invalid_op+0x1a/0x60
[ 4947.849422] ? asm_exc_invalid_op+0x1a/0x20
[ 4947.849424] ? __cfi_show_status+0x10/0x10
[ 4947.849425] ? dev_attr_show+0x24/0x60
[ 4947.849426] sysfs_kf_seq_show+0xa6/0x110
[ 4947.849433] seq_read_iter+0x16c/0x4b0
[ 4947.849436] vfs_read+0x272/0x2d0
[ 4947.849438] ksys_read+0x72/0xe0
[ 4947.849439] do_syscall_64+0x76/0xb0
[ 4947.849440] ? do_user_addr_fault+0x252/0x650
[ 4947.849442] ? exc_page_fault+0x7a/0x1b0
[ 4947.849443] entry_SYSCALL_64_after_hwframe+0x72/0xdc
Fixes: 3666062b87 ("cpufreq: amd-pstate: move to use bus_get_dev_root()")
Reported-by: Jannik Glückert <jannik.glueckert@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217765
Link: https://lore.kernel.org/lkml/c7f1bf9b-b183-bf6e-1cbb-d43f72494083@gmail.com/
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Users are having more success with amd-pstate since the introduction
of EPP and Guided modes. To expose the driver to more users by default
introduce a kernel configuration option for setting the default mode.
Users can use an integer to map out which default mode they want to use
in lieu of a kernel command line option.
This will default to EPP, but only if:
1) The CPU supports an MSR.
2) The system profile is identified
3) The system profile is identified as a non-server by the FADT.
Link: https://gitlab.freedesktop.org/hadess/power-profiles-daemon/-/merge_requests/121
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Co-developed-by: Perry Yuan <perry.yuan@amd.com>
Signed-off-by: Perry Yuan <perry.yuan@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
If a user's configuration doesn't explicitly specify the cpufreq
scaling governor then the code currently explicitly falls back to
'powersave'. This default is fine for notebooks and desktops, but
servers and undefined machines should default to 'performance'.
Look at the 'preferred_profile' field from the FADT to set this
policy accordingly.
Link: https://uefi.org/htmlspecs/ACPI_Spec_6_4_html/05_ACPI_Software_Programming_Model/ACPI_Software_Programming_Model.html#fixed-acpi-description-table-fadt
Acked-by: Huang Rui <ray.huang@amd.com>
Suggested-by: Wyes Karny <Wyes.Karny@amd.com>
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Perry Yuan <Perry.Yuan@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
amd-pstate passive mode driver is hyphenated. So make amd-pstate active
mode driver consistent with that rename "amd_pstate_epp" to
"amd-pstate-epp".
Fixes: ffa5096a7c ("cpufreq: amd-pstate: implement Pstate EPP support for the AMD processors")
Cc: All applicable <stable@vger.kernel.org>
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Signed-off-by: Wyes Karny <wyes.karny@amd.com>
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Perry Yuan <Perry.Yuan@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Currently amd_pstate sets CPPC enable bit in MSR_AMD_CPPC_ENABLE only
for the CPU where the module_init happened. But MSR_AMD_CPPC_ENABLE is
per-socket. This causes CPPC enable bit to set for only one socket for
servers with more than one physical packages. To fix this write
MSR_AMD_CPPC_ENABLE per-socket.
Also, handle duplicate calls for cppc_enable, because it's called from
per-policy/per-core callbacks and can result in duplicate MSR writes.
Before the fix:
amd@amd:~$ sudo rdmsr -a 0xc00102b1 | uniq --count
192 0
192 1
After the fix:
amd@amd:~$ sudo rdmsr -a 0xc00102b1 | uniq --count
384 1
Suggested-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Signed-off-by: Wyes Karny <wyes.karny@amd.com>
Acked-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Driver should update policy->cur after updating the frequency.
Currently amd_pstate doesn't update policy->cur when `adjust_perf`
is used. Which causes /proc/cpuinfo to show wrong cpu frequency.
Fix this by updating policy->cur with correct frequency value in
adjust_perf function callback.
- Before the fix: (setting min freq to 1.5 MHz)
[root@amd]# cat /proc/cpuinfo | grep "cpu MHz" | sort | uniq --count
1 cpu MHz : 1777.016
1 cpu MHz : 1797.160
1 cpu MHz : 1797.270
189 cpu MHz : 400.000
- After the fix: (setting min freq to 1.5 MHz)
[root@amd]# cat /proc/cpuinfo | grep "cpu MHz" | sort | uniq --count
1 cpu MHz : 1753.353
1 cpu MHz : 1756.838
1 cpu MHz : 1776.466
1 cpu MHz : 1776.873
1 cpu MHz : 1777.308
1 cpu MHz : 1779.900
183 cpu MHz : 1805.231
1 cpu MHz : 1956.815
1 cpu MHz : 2246.203
1 cpu MHz : 2259.984
Fixes: 1d215f0319 ("cpufreq: amd-pstate: Add fast switch function for AMD P-State")
Signed-off-by: Wyes Karny <wyes.karny@amd.com>
[ rjw: Subject edits ]
Cc: 5.17+ <stable@vger.kernel.org> # 5.17+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
amd_pstate active mode driver is only compatible with static governors.
Therefore it doesn't need fast_switch functionality. Remove
fast_switch_possible flag from amd_pstate active mode driver.
Fixes: ffa5096a7c ("cpufreq: amd-pstate: implement Pstate EPP support for the AMD processors")
Signed-off-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Schedutil normally calls the adjust_perf callback for drivers with
adjust_perf callback available and fast_switch_possible flag set.
However, when frequency invariance is disabled and schedutil tries to
invoke fast_switch. So, there is a chance of kernel crash if this
function pointer is not set. To protect against this scenario add
fast_switch callback to amd_pstate driver.
Fixes: 1d215f0319 ("cpufreq: amd-pstate: Add fast switch function for AMD P-State")
Signed-off-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Signed-off-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Here is the large set of driver core changes for 6.4-rc1.
Once again, a busy development cycle, with lots of changes happening in
the driver core in the quest to be able to move "struct bus" and "struct
class" into read-only memory, a task now complete with these changes.
This will make the future rust interactions with the driver core more
"provably correct" as well as providing more obvious lifetime rules for
all busses and classes in the kernel.
The changes required for this did touch many individual classes and
busses as many callbacks were changed to take const * parameters
instead. All of these changes have been submitted to the various
subsystem maintainers, giving them plenty of time to review, and most of
them actually did so.
Other than those changes, included in here are a small set of other
things:
- kobject logging improvements
- cacheinfo improvements and updates
- obligatory fw_devlink updates and fixes
- documentation updates
- device property cleanups and const * changes
- firwmare loader dependency fixes.
All of these have been in linux-next for a while with no reported
problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the large set of driver core changes for 6.4-rc1.
Once again, a busy development cycle, with lots of changes happening
in the driver core in the quest to be able to move "struct bus" and
"struct class" into read-only memory, a task now complete with these
changes.
This will make the future rust interactions with the driver core more
"provably correct" as well as providing more obvious lifetime rules
for all busses and classes in the kernel.
The changes required for this did touch many individual classes and
busses as many callbacks were changed to take const * parameters
instead. All of these changes have been submitted to the various
subsystem maintainers, giving them plenty of time to review, and most
of them actually did so.
Other than those changes, included in here are a small set of other
things:
- kobject logging improvements
- cacheinfo improvements and updates
- obligatory fw_devlink updates and fixes
- documentation updates
- device property cleanups and const * changes
- firwmare loader dependency fixes.
All of these have been in linux-next for a while with no reported
problems"
* tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (120 commits)
device property: make device_property functions take const device *
driver core: update comments in device_rename()
driver core: Don't require dynamic_debug for initcall_debug probe timing
firmware_loader: rework crypto dependencies
firmware_loader: Strip off \n from customized path
zram: fix up permission for the hot_add sysfs file
cacheinfo: Add use_arch[|_cache]_info field/function
arch_topology: Remove early cacheinfo error message if -ENOENT
cacheinfo: Check cache properties are present in DT
cacheinfo: Check sib_leaf in cache_leaves_are_shared()
cacheinfo: Allow early level detection when DT/ACPI info is missing/broken
cacheinfo: Add arm64 early level initializer implementation
cacheinfo: Add arch specific early level initializer
tty: make tty_class a static const structure
driver core: class: remove struct class_interface * from callbacks
driver core: class: mark the struct class in struct class_interface constant
driver core: class: make class_register() take a const *
driver core: class: mark class_release() as taking a const *
driver core: remove incorrect comment for device_create*
MIPS: vpe-cmp: remove module owner pointer from struct class usage.
...
smatch reports
drivers/cpufreq/amd-pstate.c:907:25: warning: symbol
'mode_state_machine' was not declared. Should it be static?
This variable is only used in one file so it should be static.
Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Wyes Karny <wyes.karny@amd.com>
Tested-by: Wyes Karny <wyes.karny@amd.com>
Reviewed-by: Dhruva Gole <d-gole@ti.com>
[ rjw: Subject edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
amd_pstate driver's `status` sysfs entry helps to control the driver's
mode dynamically by user. After the addition of guided mode the
combinations of mode transitions have been increased (16 combinations).
Therefore optimise the amd_pstate_update_status function by implementing
a state transition table.
There are 4 states amd_pstate supports, namely: 'disable', 'passive',
'active', and 'guided'. The transition from any state to any other
state is possible after this change.
Sysfs interface:
To disable amd_pstate driver:
# echo disable > /sys/devices/system/cpu/amd_pstate/status
To enable passive mode:
# echo passive > /sys/devices/system/cpu/amd_pstate/status
To change mode to active:
# echo active > /sys/devices/system/cpu/amd_pstate/status
To change mode to guided:
# echo guided > /sys/devices/system/cpu/amd_pstate/status
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
From ACPI spec below 3 modes for CPPC can be defined:
1. Non autonomous: OS scaling governor specifies operating frequency/
performance level through `Desired Performance` register and platform
follows that.
2. Guided autonomous: OS scaling governor specifies min and max
frequencies/ performance levels through `Minimum Performance` and
`Maximum Performance` register, and platform can autonomously select an
operating frequency in this range.
3. Fully autonomous: OS only hints (via EPP) to platform for the required
energy performance preference for the workload and platform autonomously
scales the frequency.
Currently (1) is supported by amd_pstate as passive mode, and (3) is
implemented by EPP support. This change is to support (2).
In guided autonomous mode the min_perf is based on the input from the
scaling governor. For example, in case of schedutil this value depends
on the current utilization. And max_perf is set to max capacity.
To activate guided auto mode ``amd_pstate=guided`` command line
parameter has to be passed in the kernel.
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Direct access to the struct bus_type dev_root pointer is going away soon
so replace that with a call to bus_get_dev_root() instead, which is what
it is there for.
In doing so, remove the unneded kobject structure that was only being
created to cause a subdirectory for the attributes. The name of the
attribute group is the correct way to do this, saving code and
complexity as well as allowing the attributes to properly show up to
userspace tools (the raw kobject would not allow that.)
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linux-pm@vger.kernel.org
Acked-by: Huang Rui <ray.huang@.amd.com>
Link: https://lore.kernel.org/r/20230313182918.1312597-20-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since commit 8b41fc4454 ("kbuild: create modules.builtin without
Makefile.modbuiltin or tristate.conf"), MODULE_LICENSE declarations
are used to identify modules. As a consequence, uses of the macro
in non-modules will cause modprobe to misidentify their containing
object file as a module when it is not (false positives), and modprobe
might succeed rather than failing with a suitable error message.
So remove it in amd-pstate.c which cannot be built as a module.
Signed-off-by: Nick Alcock <nick.alcock@oracle.com>
Suggested-by: Luis Chamberlain <mcgrof@kernel.org>
[ rjw: Subject and changelog adjustments ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit 202e683df3 ("cpufreq: amd-pstate: add amd-pstate driver
parameter for mode selection") changed the driver to be disabled by
default, and this can surprise users.
Let users know what happened so they can decide what to do next.
Link: https://bugs.launchpad.net/bugs/2006942
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Yuan Perry <Perry.Yuan@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The new epp support causes warnings about three separate
but related bugs:
1) failing before allocation should just return an error:
drivers/cpufreq/amd-pstate.c:951:6: error: variable 'ret' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
if (!dev)
^~~~
drivers/cpufreq/amd-pstate.c:1018:9: note: uninitialized use occurs here
return ret;
^~~
2) wrong variable to store return code:
drivers/cpufreq/amd-pstate.c:963:6: error: variable 'ret' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
if (rc)
^~
drivers/cpufreq/amd-pstate.c:1019:9: note: uninitialized use occurs here
return ret;
^~~
drivers/cpufreq/amd-pstate.c:963:2: note: remove the 'if' if its condition is always false
if (rc)
^~~~~~~
3) calling amd_pstate_set_epp() in cleanup path after determining
that it should not be called:
drivers/cpufreq/amd-pstate.c:1055:6: error: variable 'epp' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
if (cpudata->epp_policy == cpudata->policy)
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/cpufreq/amd-pstate.c:1080:30: note: uninitialized use occurs here
amd_pstate_set_epp(cpudata, epp);
^~~
All three are trivial to fix, but most likely there are additional bugs
in this function when the error handling was not really tested.
Fixes: ffa5096a7c ("cpufreq: amd-pstate: implement Pstate EPP support for the AMD processors")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Wyes Karny <wyes.karny@amd.com>
Reviewed-by: Yuan Perry <Perry.Yuan@amd.com>
Acked-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
All but a few drivers ignore the return value of
cpufreq_unregister_driver(). Those few that don't only call it after
cpufreq_register_driver() succeeded, in which case the call doesn't
fail.
Make the function return no value and add a WARN_ON for the case that
the function is called in an invalid situation (i.e. without a previous
successful call to cpufreq_register_driver()).
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Florian Fainelli <f.fainelli@gmail.com> # brcmstb-avs-cpufreq.c
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
replace the sprintf with a more generic sysfs_emit function
No intended potential function impact
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Wyes Karny <wyes.karny@amd.com>
Tested-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Perry Yuan <perry.yuan@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
While amd-pstate driver was loaded with specific driver mode, it will
need to check which mode is enabled for the pstate driver,add this sysfs
entry to show the current status
$ cat /sys/devices/system/cpu/amd-pstate/status
active
Meanwhile, user can switch the pstate driver mode with writing mode
string to sysfs entry as below.
Enable passive mode:
$ sudo bash -c "echo passive > /sys/devices/system/cpu/amd-pstate/status"
Enable active mode (EPP driver mode):
$ sudo bash -c "echo active > /sys/devices/system/cpu/amd-pstate/status"
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Wyes Karny <wyes.karny@amd.com>
Tested-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
add suspend and resume support for the AMD processors by amd_pstate_epp
driver instance.
When the CPPC is suspended, EPP driver will set EPP profile to 'power'
profile and set max/min perf to lowest perf value.
When resume happens, it will restore the MSR registers with
previous cached value.
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Mario Limonciello <Mario.Limonciello@amd.com>
Reviewed-by: Wyes Karny <wyes.karny@amd.com>
Tested-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Adds online and offline driver callback support to allow cpu cores go
offline and help to restore the previous working states when core goes
back online later for EPP driver mode.
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Mario Limonciello <Mario.Limonciello@amd.com>
Reviewed-by: Wyes Karny <wyes.karny@amd.com>
Tested-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add EPP driver support for AMD SoCs which support a dedicated MSR for
CPPC. EPP is used by the DPM controller to configure the frequency that
a core operates at during short periods of activity.
The SoC EPP targets are configured on a scale from 0 to 255 where 0
represents maximum performance and 255 represents maximum efficiency.
The amd-pstate driver exports profile string names to userspace that are
tied to specific EPP values.
The balance_performance string (0x80) provides the best balance for
efficiency versus power on most systems, but users can choose other
strings to meet their needs as well.
$ cat /sys/devices/system/cpu/cpufreq/policy0/energy_performance_available_preferences
default performance balance_performance balance_power power
$ cat /sys/devices/system/cpu/cpufreq/policy0/energy_performance_preference
balance_performance
To enable the driver,it needs to add `amd_pstate=active` to kernel
command line and kernel will load the active mode epp driver
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Mario Limonciello <Mario.Limonciello@amd.com>
Reviewed-by: Wyes Karny <wyes.karny@amd.com>
Tested-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The amd-pstate driver may support multiple working modes.
Introduce a variable to keep track of which mode is currently enabled.
Here we use cppc_state var to indicate which mode is enabled.
This change will help to simplify the the amd_pstate_param() to choose
which mode used for the following driver registration.
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Tested-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Perry Yuan <perry.yuan@amd.com>
Signed-off-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In the amd_pstate_adjust_perf(), there is one cpufreq_cpu_get() call to
increase increments the kobject reference count of policy and make it as
busy. Therefore, a corresponding call to cpufreq_cpu_put() is needed to
decrement the kobject reference count back, it will resolve the kernel
hang issue when unregistering the amd-pstate driver and register the
`amd_pstate_epp` driver instance.
Fixes: 1d215f0319 ("cpufreq: amd-pstate: Add fast switch function for AMD P-State")
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Tested-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Perry Yuan <perry.yuan@amd.com>
Cc: 5.17+ <stable@vger.kernel.org> # 5.17+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
When the amd_pstate driver is built-in users still need a method to be
able enable or disable it depending upon their circumstance.
Add support for an early parameter to do this.
There is some performance degradation on a number of ASICs in the
passive mode. This performance issue was originally discovered in
shared memory systems but it has been proven that certain workloads
on MSR systems also suffer performance issues.
Set the amd-pstate driver as disabled by default to temporarily
mitigate the performance problem.
1) with `amd_pstate=disable`, pstate driver will be disabled to load at
kernel booting.
2) with `amd_pstate=passive`, pstate driver will be enabled and loaded
as non-autonomous working mode supported in the low-level power
management firmware.
3) If neither parameter is specified, the driver will be disabled by
default to avoid triggering performance regressions in certain ASICs
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Tested-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Currently when the amd-pstate and acpi_cpufreq are both built into
kernel as module driver, amd-pstate will not be loaded by default
in this case.
Change amd-pstate driver as built-in type, it will resolve the loading
sequence problem to allow user to make amd-pstate driver as the default
cpufreq scaling driver.
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Tested-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
Fixes: ec437d71db ("cpufreq: amd-pstate: Introduce a new AMD P-State driver to support future processors")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
MSR_AMD_PERF_CTL is guaranteed to be 0 on a cold boot. However, on a
kexec boot, for instance, it may have a non-zero value (if the cpu was
in a non-P0 Pstate). In such cases, the cores with non-P0 Pstates at
boot will never be pushed to P0, let alone boost frequencies.
Kexec is a common workflow for reboot on Linux and this creates a
regression in performance. Fix it by explicitly setting the
MSR_AMD_PERF_CTL to 0 during amd_pstate driver init.
Cc: All applicable <stable@vger.kernel.org>
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Tested-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This Kselftest update for Linux 6.1-rc1 consists of fixes and new tests.
- Adds a amd-pstate-ut test module, this module is used by kselftest
to unit test amd-pstate functionality
- Fixes and cleanups to to cpu-hotplug to delete the fault injection
test code
- Improvements to vm test to use top_srcdir for builds
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Merge tag 'linux-kselftest-next-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull Kselftest updates from Shuah Khan:
"Fixes and new tests:
- Add an amd-pstate-ut test module, used by kselftest to unit test
amd-pstate functionality
- Fixes and cleanups to to cpu-hotplug to delete the fault injection
test code
- Improvements to vm test to use top_srcdir for builds"
* tag 'linux-kselftest-next-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
docs:kselftest: fix kselftest_module.h path of example module
cpufreq: amd-pstate: Add explanation for X86_AMD_PSTATE_UT
selftests/cpu-hotplug: Add log info when test success
selftests/cpu-hotplug: Reserve one cpu online at least
selftests/cpu-hotplug: Delete fault injection related code
selftests/cpu-hotplug: Use return instead of exit
selftests/cpu-hotplug: Correct log info
cpufreq: amd-pstate: modify type in argument 2 for filp_open
Documentation: amd-pstate: Add unit test introduction
selftests: amd-pstate: Add test trigger for amd-pstate driver
cpufreq: amd-pstate: Add test module for amd-pstate driver
cpufreq: amd-pstate: Expose struct amd_cpudata
selftests/vm: use top_srcdir instead of recomputing relative paths
Expose struct amd_cpudata to AMD P-State unit test module.
This data struct will be used on the following AMD P-State unit test
(amd-pstate-ut) module. The amd-pstate-ut module can get some
AMD infomations by this data struct. For example: highest perf,
nominal perf, boost supported etc.
Signed-off-by: Meng Li <li.meng@amd.com>
Acked-by: Huang Rui <ray.huang@amd.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
- Add isupport for Tiger Lake in no-HWP mode to intel_pstate (Doug
Smythies).
- Update the AMD P-state driver (Perry Yuan):
* Fix wrong lowest perf fetch.
* Map desired perf into pstate scope for powersave governor.
* Update pstate frequency transition delay time.
* Fix initial highest_perf value.
* Clean up.
- Move max CPU capacity to sugov_policy in the schedutil cpufreq
governor (Lukasz Luba).
- Add SM6115 to cpufreq-dt blocklist (Adam Skladowski).
- Add support for Tegra239 and minor cleanups (Sumit Gupta, ye xingchen,
and Yang Yingliang).
- Add freq qos for qcom cpufreq driver and minor cleanups (Xuewen Yan,
and Viresh Kumar).
- Minor cleanups around functions called at module_init() (Xiu Jianfeng).
- Use module_init and add module_exit for bmips driver (Zhang Jianhua).
- Add AlderLake-N support to intel_idle (Zhang Rui).
- Replace strlcpy() with unused retval with strscpy() in intel_idle
(Wolfram Sang).
- Remove redundant check from cpuidle_switch_governor() (Yu Liao).
- Replace strlcpy() with unused retval with strscpy() in the powernv
cpuidle driver (Wolfram Sang).
- Drop duplicate word from a comment in the coupled cpuidle driver
(Jason Wang).
- Make rpm_resume() return -EINPROGRESS if RPM_NOWAIT is passed to it
in the flags and the device is about to resume (Rafael Wysocki).
- Add extra debugging statement for multiple active IRQs to system
wakeup handling code (Mario Limonciello).
- Replace strlcpy() with unused retval with strscpy() in the core
system suspend support code (Wolfram Sang).
- Update the intel_rapl power capping driver:
* Use standard Energy Unit for SPR Dram RAPL domain (Zhang Rui).
* Add support for RAPTORLAKE_S (Zhang Rui).
* Fix UBSAN shift-out-of-bounds issue (Chao Qin).
- Handle -EPROBE_DEFER when regulator is not probed on
mtk-ci-devfreq.c (AngeloGioacchino Del Regno).
- Fix message typo and use dev_err_probe() in rockchip-dfi.c
(Christophe JAILLET).
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Merge tag 'pm-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"These add support for some new hardware, extend the existing hardware
support, fix some issues and clean up code
Specifics:
- Add isupport for Tiger Lake in no-HWP mode to intel_pstate (Doug
Smythies)
- Update the AMD P-state driver (Perry Yuan):
- Fix wrong lowest perf fetch
- Map desired perf into pstate scope for powersave governor
- Update pstate frequency transition delay time
- Fix initial highest_perf value
- Clean up
- Move max CPU capacity to sugov_policy in the schedutil cpufreq
governor (Lukasz Luba)
- Add SM6115 to cpufreq-dt blocklist (Adam Skladowski)
- Add support for Tegra239 and minor cleanups (Sumit Gupta, ye
xingchen, and Yang Yingliang)
- Add freq qos for qcom cpufreq driver and minor cleanups (Xuewen
Yan, and Viresh Kumar)
- Minor cleanups around functions called at module_init() (Xiu
Jianfeng)
- Use module_init and add module_exit for bmips driver (Zhang
Jianhua)
- Add AlderLake-N support to intel_idle (Zhang Rui)
- Replace strlcpy() with unused retval with strscpy() in intel_idle
(Wolfram Sang)
- Remove redundant check from cpuidle_switch_governor() (Yu Liao)
- Replace strlcpy() with unused retval with strscpy() in the powernv
cpuidle driver (Wolfram Sang)
- Drop duplicate word from a comment in the coupled cpuidle driver
(Jason Wang)
- Make rpm_resume() return -EINPROGRESS if RPM_NOWAIT is passed to it
in the flags and the device is about to resume (Rafael Wysocki)
- Add extra debugging statement for multiple active IRQs to system
wakeup handling code (Mario Limonciello)
- Replace strlcpy() with unused retval with strscpy() in the core
system suspend support code (Wolfram Sang)
- Update the intel_rapl power capping driver:
- Use standard Energy Unit for SPR Dram RAPL domain (Zhang Rui).
- Add support for RAPTORLAKE_S (Zhang Rui).
- Fix UBSAN shift-out-of-bounds issue (Chao Qin)
- Handle -EPROBE_DEFER when regulator is not probed on
mtk-ci-devfreq.c (AngeloGioacchino Del Regno)
- Fix message typo and use dev_err_probe() in rockchip-dfi.c
(Christophe JAILLET)"
* tag 'pm-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (29 commits)
cpufreq: qcom-cpufreq-hw: Add cpufreq qos for LMh
cpufreq: Add __init annotation to module init funcs
cpufreq: tegra194: change tegra239_cpufreq_soc to static
PM / devfreq: rockchip-dfi: Fix an error message
PM / devfreq: mtk-cci: Handle sram regulator probe deferral
powercap: intel_rapl: Use standard Energy Unit for SPR Dram RAPL domain
PM: runtime: Return -EINPROGRESS from rpm_resume() in the RPM_NOWAIT case
intel_idle: Add AlderLake-N support
powercap: intel_rapl: fix UBSAN shift-out-of-bounds issue
cpufreq: tegra194: Add support for Tegra239
cpufreq: qcom-cpufreq-hw: Fix uninitialized throttled_freq warning
cpufreq: intel_pstate: Add Tigerlake support in no-HWP mode
powercap: intel_rapl: Add support for RAPTORLAKE_S
cpufreq: amd-pstate: Fix initial highest_perf value
cpuidle: Remove redundant check in cpuidle_switch_governor()
PM: wakeup: Add extra debugging statement for multiple active IRQs
cpufreq: tegra194: Remove the unneeded result variable
PM: suspend: move from strlcpy() with unused retval to strscpy()
intel_idle: move from strlcpy() with unused retval to strscpy()
cpuidle: powernv: move from strlcpy() with unused retval to strscpy()
...
To avoid some new AMD processors use wrong highest perf when amd pstate
driver loaded, this fix will query the highest perf from MSR register
MSR_AMD_CPPC_CAP1 and cppc_acpi interface firstly, then compare with the
highest perf value got by calling amd_get_highest_perf() function.
The lower value will be the correct highest perf we need to use.
Otherwise the CPU max MHz will be incorrect if the
amd_get_highest_perf() did not cover the new process family and model ID.
Like this lscpu info, the max frequency is incorrect.
Vendor ID: AuthenticAMD
Socket(s): 1
Stepping: 2
CPU max MHz: 5410.0000
CPU min MHz: 400.0000
BogoMIPS: 5600.54
Fixes: 3743d55b28 (x86, sched: Fix the AMD CPPC maximum performance value on certain AMD Ryzen generations)
Acked-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Change the default transition latency to be 20ms that is more
reasonable transition delay for AMD processors in non-EPP driver mode.
Update transition delay time to 1ms, in the AMD CPU autonomous mode and
non-autonomous mode, CPPC firmware will decide frequency at 1ms timescale
based on the workload utilization.
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The patch will fix the invalid desired perf value for powersave
governor. This issue is found when testing on one AMD EPYC system, the
actual des_perf is smaller than the min_perf value, that is invalid
value. because the min_perf is the lowest_perf system can support in
idle state.
Reviewed-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Fix the wrong lowest perf value reading which is used for new
des_perf calculation by governor requested, the incorrect min_perf will
get incorrect des_perf to be set , that will cause the system frequency
changing unexpectedly.
Reviewed-by: Huang Rui <ray.huang@amd.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
Signed-off-by: Su Jinzhou <jinzhou.su@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Remove the white space and correct mixed-up indentation
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
move the cpudata assignment to cpudata declaration which
will simplify the functions.
No functional change intended.
Reviewed-by: Huang Rui <ray.huang@amd.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Make acpi_cpc_valid() check if ACPI is disabled, so that its callers
don't need to check that separately. This will also cause the AMD
pstate driver to refuse to load right away when ACPI is disabled.
Also update the warning message in amd_pstate_init() to mention the
ACPI disabled case for completeness.
Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
[ rjw: Subject edits, new changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
When system resumes from S3, the CPPC enable register will be
cleared and reset to 0.
So enable the CPPC interface by writing 1 to this register on
system resume and disable it during system suspend.
Signed-off-by: Jinzhou Su <Jinzhou.Su@amd.com>
Signed-off-by: Jinzhou Su <Jinzhou.Su@amd.com>
Acked-by: Huang Rui <ray.huang@amd.com>
[ rjw: Subject and changelog edits ]
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add frequency, mperf, aperf and tsc in the trace. This can be used
to debug and tune the performance of AMD P-state driver.
Use the time difference between amd_pstate_update to calculate CPU
frequency. There could be sleep in arch_freq_get_on_cpu, so do not
use it here.
Signed-off-by: Jinzhou Su <Jinzhou.Su@amd.com>
Co-developed-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add the description of @req and @boost_supported in struct amd_cpudata
kernel-doc comment to remove warnings found by running scripts/kernel-doc,
which is caused by using 'make W=1'.
drivers/cpufreq/amd-pstate.c:104: warning: Function parameter or member
'req' not described in 'amd_cpudata'
drivers/cpufreq/amd-pstate.c:104: warning: Function parameter or member
'boost_supported' not described in 'amd_cpudata'
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Acked-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Introduce sysfs attributes to get the different level AMD P-State
performances.
Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Introduce sysfs attributes to get the different level processor
frequencies.
Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
If the sbios supports the boost mode of AMD P-State, let's switch to
boost enabled by default.
Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add trace event to monitor the performance value changes which is
controlled by cpu governors.
Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In some of Zen2 and Zen3 based processors, they are using the shared
memory that exposed from ACPI SBIOS. In this kind of the processors,
there is no MSR support, so we add acpi cppc function as the backend for
them.
It is using a module param (shared_mem) to enable related processors
manually. We will enable this by default once we address performance
issue on this solution.
Signed-off-by: Jinzhou Su <Jinzhou.Su@amd.com>
Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Introduce the fast switch function for AMD P-State on the AMD processors
which support the full MSR register control. It's able to decrease the
latency on interrupt context.
Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
