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: NPerry Yuan <Perry.Yuan@amd.com>
[ rjw: Subject edits, new changelog ]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

There is a problem with the current revision checks in
is_cppc_supported() that they essentially prevent the CPPC support
from working if a new _CPC package format revision being a proper
superset of the v3 and only causing _CPC to return a package with more
entries (while retaining the types and meaning of the entries defined by
the v3) is introduced in the future and used by the platform firmware.

In that case, as long as the number of entries in the _CPC return
package is at least CPPC_V3_NUM_ENT, it should be perfectly fine to
use the v3 support code and disregard the additional package entries
added by the new package format revision.

For this reason, drop is_cppc_supported() altogether, put the revision
checks directly into acpi_cppc_processor_probe() so they are easier to
follow and rework them to take the case mentioned above into account.

Fixes: 4773e77c ("ACPI / CPPC: Add support for CPPC v3")
Cc: 4.18+ <stable@vger.kernel.org> # 4.18+
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Commit 0651ab90 ("ACPI: CPPC: Check _OSC for flexible address space")
changed _CPC probing to require flexible address space to be negotiated
for CPPC to work.

However it was observed that this caused a regression for Arek's ROG
Zephyrus G15 GA503QM which previously CPPC worked, but now it stopped
working.

To avoid causing a regression waive this failure when the CPU is known
to support CPPC.

Cc: Pierre Gondois <pierre.gondois@arm.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216248
Fixes: 0651ab90 ("ACPI: CPPC: Check _OSC for flexible address space")
Reported-and-tested-by: NArek Ruśniak <arek.rusi@gmail.com>
Signed-off-by: NMario Limonciello <mario.limonciello@amd.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

commit 72f2ecb7 ("ACPI: bus: Set CPPC _OSC bits for all and
when CPPC_LIB is supported") added support for claiming to
support CPPC in _OSC on non-Intel platforms.

This unfortunately caused a regression on a vartiety of AMD
platforms in the field because a number of AMD platforms don't set
the `_OSC` bit 5 or 6 to indicate CPPC or CPPC v2 support.

As these AMD platforms already claim CPPC support via a dedicated
MSR from `X86_FEATURE_CPPC`, use this enable this feature rather
than requiring the `_OSC` on platforms with a dedicated MSR.

If there is additional breakage on the shared memory designs also
missing this _OSC, additional follow up changes may be needed.

Fixes: 72f2ecb7 ("Set CPPC _OSC bits for all and when CPPC_LIB is supported")
Reported-by: NPerry Yuan <perry.yuan@amd.com>
Signed-off-by: NMario Limonciello <mario.limonciello@amd.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Previously the kernel used to ignore whether the firmware masked CPPC
or CPPCv2 and would just pretend that it worked.

When support for the USB4 bit in _OSC was introduced from commit
9e1f561afb ("ACPI: Execute platform _OSC also with query bit clear")
the kernel began to look at the return when the query bit was clear.

This caused regressions that were misdiagnosed and attempted to be solved
as part of commit 2ca8e628 ("Revert "ACPI: Pass the same capabilities
to the _OSC regardless of the query flag""). This caused a different
regression where non-Intel systems weren't able to negotiate _OSC
properly.

This was reverted in commit 2ca8e628 ("Revert "ACPI: Pass the same
capabilities to the _OSC regardless of the query flag"") and attempted to
be fixed by commit c42fa24b ("ACPI: bus: Avoid using CPPC if not
supported by firmware") but the regression still returned.

These systems with the regression only load support for CPPC from an SSDT
dynamically when _OSC reports CPPC v2.  Avoid the problem by not letting
CPPC satisfy the requirement in `acpi_cppc_processor_probe`.
Reported-by: NCUI Hao <cuihao.leo@gmail.com>
Reported-by: maxim.novozhilov@gmail.com
Reported-by: lethe.tree@protonmail.com
Reported-by: garystephenwright@gmail.com
Reported-by: galaxyking0419@gmail.com
Fixes: c42fa24b ("ACPI: bus: Avoid using CPPC if not supported by firmware")
Fixes: 2ca8e628 ("Revert "ACPI Pass the same capabilities to the _OSC regardless of the query flag"")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=213023
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2075387Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: NCUI Hao <cuihao.leo@gmail.com>
Signed-off-by: NMario Limonciello <mario.limonciello@amd.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Spelling mistake (triple letters) in comment.
Detected with the help of Coccinelle.
Signed-off-by: NJulia Lawall <Julia.Lawall@inria.fr>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The communication mean of the _CPC desired performance can be
PCC, System Memory, System IO, or Functional Fixed Hardware.

commit b7898fda ("cpufreq: Support for fast frequency switching")
fast_switching is 'for switching CPU frequencies from interrupt
context'.
Writes to SystemMemory and SystemIo are fast and suitable this.
This is not the case for PCC and might not be the case for FFH.

Enable fast_switching for the cppc_cpufreq driver in above cases.

Add cppc_allow_fast_switch() to check the desired performance
register address space and set fast_switching accordingly.
Signed-off-by: NPierre Gondois <pierre.gondois@arm.com>
Reviewed-by: NSudeep Holla <sudeep.holla@arm.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The transition_delay_us (struct cpufreq_policy) is currently defined
as:
  Preferred average time interval between consecutive invocations of
  the driver to set the frequency for this policy.  To be set by the
  scaling driver (0, which is the default, means no preference).
The transition_latency represents the amount of time necessary for a
CPU to change its frequency.

A PCCT table advertises mutliple values:
- pcc_nominal: Expected latency to process a command, in microseconds
- pcc_mpar: The maximum number of periodic requests that the subspace
  channel can support, reported in commands per minute. 0 indicates no
  limitation.
- pcc_mrtt: The minimum amount of time that OSPM must wait after the
  completion of a command before issuing the next command,
  in microseconds.
cppc_get_transition_latency() allows to get the max of them.

commit d4f3388a ("cpufreq / CPPC: Set platform specific
transition_delay_us") allows to select transition_delay_us based on
the platform, and fallbacks to cppc_get_transition_latency()
otherwise.

If _CPC objects are not using PCC channels (no PPCT table), the
transition_delay_us is set to CPUFREQ_ETERNAL, leading to really long
periods between frequency updates (~4s).

If the desired_reg, where performance requests are written, is in
SystemMemory or SystemIo ACPI address space, there is no delay
in requests. So return 0 instead of CPUFREQ_ETERNAL, leading to
transition_delay_us being set to LATENCY_MULTIPLIER us (1000 us).

This patch also adds two macros to check the address spaces.
Signed-off-by: NPierre Gondois <pierre.gondois@arm.com>
Reviewed-by: NSudeep Holla <sudeep.holla@arm.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPI 6.2 Section 6.2.11.2 'Platform-Wide OSPM Capabilities':
  Starting with ACPI Specification 6.2, all _CPC registers can be in
  PCC, System Memory, System IO, or Functional Fixed Hardware address
  spaces. OSPM support for this more flexible register space scheme is
  indicated by the “Flexible Address Space for CPPC Registers” _OSC bit

Otherwise (cf ACPI 6.1, s8.4.7.1.1.X), _CPC registers must be in:
- PCC or Functional Fixed Hardware address space if defined
- SystemMemory address space (NULL register) if not defined

Add the corresponding _OSC bit and check it when parsing _CPC objects.
Signed-off-by: NPierre Gondois <pierre.gondois@arm.com>
Reviewed-by: NSudeep Holla <sudeep.holla@arm.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Change the default error code returned by acpi_cppc_processor_probe()
from -EFAULT (which is completely inadequate) to -ENODATA and change
the debug messages printed by it to contain more information and be
more consistent.

While at it, format some white space to follow the coding style.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NHuang Rui <ray.huang@amd.com>

If the NumEntries field in the _CPC return package is less than 2, do
not attempt to access the "Revision" element of that package, because
it may not be present then.

Fixes: 337aadff ("ACPI: Introduce CPU performance controls using CPPC")
BugLink: https://lore.kernel.org/lkml/20220322143534.GC32582@xsang-OptiPlex-9020/Reported-by: Nkernel test robot <oliver.sang@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NHuang Rui <ray.huang@amd.com>

If the platform firmware indicates that it does not support CPPC by
clearing the OSC_SB_CPC_SUPPORT and OSC_SB_CPCV2_SUPPORT bits in the
platform _OSC capabilities mask, avoid attempting to evaluate _CPC
which may fail in that case.

Because the OSC_SB_CPC_SUPPORT and OSC_SB_CPCV2_SUPPORT bits are only
added to the supported platform capabilities mask on x86, when
X86_FEATURE_HWP is supported, allow _CPC to be evaluated regardless
in the other cases.

Link: https://lore.kernel.org/linux-acpi/CAJZ5v0i=ecAksq0TV+iLVObm-=fUfdqPABzzkgm9K6KxO1ZCcg@mail.gmail.comSigned-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: NMario Limonciello <mario.limonciello@amd.com>
Acked-by: NHuang Rui <ray.huang@amd.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>

init_freq_invariance_cppc() was called in acpi_cppc_processor_probe(),
after CPU performance information and controls were populated from the
per-cpu _CPC objects.

But these _CPC objects provide information that helps with both CPU
(u-arch) and frequency invariance. Therefore, change the function name
to a more generic one, while adding the arch_ prefix, as this function
is expected to be defined differently by different architectures.
Signed-off-by: NIonela Voinescu <ionela.voinescu@arm.com>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: NValentin Schneider <valentin.schneider@arm.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The ret_val local variable in cpc_read() is not necessary, so
eliminate it.

No functional impact.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NHuang Rui <ray.huang@amd.com>

The code as currently implemented does not work on big endian systems,
so fix it up.

Fixes: a2c8f92b ("ACPI: CPPC: Implement support for SystemIO registers")
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Suggested-by: NDan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/linux-acpi/20220111092928.GA24968@kili/Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NHuang Rui <ray.huang@amd.com>

Add a new function to enable CPPC feature. This function
will write Continuous Performance Control package
EnableRegister field on the processor.

CPPC EnableRegister register described in section 8.4.7.1 of ACPI 6.4:
This element is optional. If supported, contains a resource descriptor
with a single Register() descriptor that describes a register to which
OSPM writes a One to enable CPPC on this processor. Before this register
is set, the processor will be controlled by legacy mechanisms (ACPI
Pstates, firmware, etc.).

This register will be used for AMD processors to enable AMD P-State
function instead of legacy ACPI P-States.
Signed-off-by: NJinzhou Su <Jinzhou.Su@amd.com>
Signed-off-by: NHuang Rui <ray.huang@amd.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

As this is a static check, it should be based upon what is currently
present on the system. This makes probeing more deterministic.

While local APIC flags field (lapic_flags) of cpu core in MADT table is
0, then the cpu core won't be enabled. In this case, _CPC won't be found
in this core, and return back to _CPC invalid with walking through
possible cpus (include disable cpus). This is not expected, so switch to
check present CPUs instead.
Reported-by: NJinzhou Su <Jinzhou.Su@amd.com>
Signed-off-by: NMario Limonciello <mario.limonciello@amd.com>
Signed-off-by: NHuang Rui <ray.huang@amd.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

According to the ACPI v6.2 (and later) specification, SystemIO can be
used for _CPC registers. This teaches cppc_acpi how to handle such
registers.

This patch was tested using the amd_pstate driver on my Zephyrus G15
(model GA503QS) using the current version 410 BIOS, which uses
a SystemIO register for the HighestPerformance element in _CPC.
Signed-off-by: NSteven Noonan <steven@valvesoftware.com>
Signed-off-by: NHuang Rui <ray.huang@amd.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

There are currently 2 ways to create a set of sysfs files for a
kobj_type, through the default_attrs field, and the default_groups
field.  Move the ACPI sysfs code to use default_groups field which has
been the preferred way since aa30f47c ("kobject: Add support for
default attribute groups to kobj_type") so that we can soon get rid of
the obsolete default_attrs field.
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Currently it's too hard to read the _CPC structure as it's commented.
Reshuffle indentation and style to make it readable.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Check cpc_desc against NULL in cppc_get_perf(), so it doesn't crash
down the road if cpc_desc is NULL.

Fixes: 0654cf05 ("ACPI: CPPC: Introduce cppc_get_nominal_perf()")
Reported-by: NKai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: 5.15+ <stable@vger.kernel.org> # 5.15+
Tested-by: NKai-Heng Feng <kai.heng.feng@canonical.com>

Now that we have all the shared memory region information populated in
the pcc_mbox_chan, let us propagate the pointer to the same as the
return value to pcc_mbox_request channel.

This eliminates the need for the individual users of PCC mailbox to
parse the PCCT subspace entries and fetch the shmem information. This
also eliminates the need for PCC mailbox controller to set con_priv to
PCCT subspace entries. This is required as con_priv is private to the
controller driver to attach private data associated with the channel and
not meant to be used by the mailbox client/users.

Let us convert all the users of pcc_mbox_{request,free}_channel to use
new interface.

Cc: Jean Delvare <jdelvare@suse.com>
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>
Acked-by: NWolfram Sang <wsa@kernel.org>
Acked-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NJassi Brar <jaswinder.singh@linaro.org>

On some systems the nominal_perf value retrieved via CPPC is just
a constant and fetching it doesn't require accessing any registers,
so if it is the only CPPC capability that's needed, it is wasteful
to run cppc_get_perf_caps() in order to get just that value alone,
especially when this is done for CPUs other than the one running
the code.

For this reason, introduce cppc_get_nominal_perf() allowing
nominal_perf to be obtained individually, by generalizing the
existing cppc_get_desired_perf() (and renaming it) so it can be
used to retrieve any specific CPPC capability value.

While at it, clean up the cppc_get_desired_perf() kerneldoc comment
a bit.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

All of the CPPC sysfs show functions are called via indirect call in
kobj_attr_show(), where they should be of type

ssize_t (*show)(struct kobject *kobj, struct kobj_attribute *attr, char *buf);

because that is the type of the ->show() member in
'struct kobj_attribute' but they are actually of type

ssize_t (*show)(struct kobject *kobj, struct attribute *attr, char *buf);

because of the ->show() member in 'struct cppc_attr', resulting in a
Control Flow Integrity violation [1].

$ cat /sys/devices/system/cpu/cpu0/acpi_cppc/highest_perf
3400

$ dmesg | grep "CFI failure"
[  175.970559] CFI failure (target: show_highest_perf+0x0/0x8):

As far as I can tell, the only difference between 'struct cppc_attr'
and 'struct kobj_attribute' aside from the type of the attr parameter
is the type of the count parameter in the ->store() member (ssize_t vs.
size_t), which does not actually matter because all of these nodes are
read-only.

Eliminate 'struct cppc_attr' in favor of 'struct kobj_attribute' to fix
the violation.

[1]: https://lore.kernel.org/r/20210401233216.2540591-1-samitolvanen@google.com/

Fixes: 158c998e ("ACPI / CPPC: add sysfs support to compute delivered performance")
Link: https://github.com/ClangBuiltLinux/linux/issues/1343Signed-off-by: NNathan Chancellor <nathan@kernel.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Fix some coding style issues reported by checkpatch.pl, including the
following types:

WARNING: Missing a blank line after declarations
WARNING: unnecessary whitespace before a quoted newline
ERROR: spaces required around that '>='
ERROR: switch and case should be at the same indent
Signed-off-by: NXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

For convenience, add empty stubs of library functions defined in
cppc_acpi.c for the CONFIG_ACPI_CPPC_LIB unset case.

Because one of them needs to return CPUFREQ_ETERNAL, include
linux/cpufreq.h into the CPPC library header file and drop the
direct inclusion of it from cppc_acpi.c.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: NChen Yu <yu.c.chen@intel.com>

Fix trivial ACPI driver comment typos.

s/notifcations/notifications/
s/Ajust/Adjust/
s/preform/perform/
s/atrributes/attributes/
s/Souce/Source/
s/Evalutes/Evaluates/
s/Evalutes/Evaluates/
s/specifiy/specify/
s/promixity/proximity/
s/presuambly/presumably/
s/Evalute/Evaluate/
s/specificed/specified/
s/rountine/routine/
s/previosuly/previously/

Change comment referencing pcc_send_cmd to send_pcc_cmd.
Signed-off-by: NTom Saeger <tom.saeger@oracle.com>
Reviewed-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Properly initialise vaddr pointers in cpc_read() and cpc_write() to
NULL instead of 0.

This fixes the following sparse warnings:

drivers/acpi/cppc_acpi.c:937:31: warning: Using plain integer as NULL pointer
drivers/acpi/cppc_acpi.c:982:31: warning: Using plain integer as NULL pointer
Signed-off-by: NIonela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

ppc_comm_addr is a virtual address to the PCC space and it's annotated
with __iomem. Therefore, generic_comm_base which gets assigned the value of
pcc_comm_address should be annotated as well.

This already happens in check_pcc_chan(), but not in send_pcc_cmd(), which
results in the following sparse warnings:

drivers/acpi/cppc_acpi.c:237:18: warning: cast removes address space '__iomem' of expression
drivers/acpi/cppc_acpi.c:299:9: warning: incorrect type in argument 2 (different address spaces)
drivers/acpi/cppc_acpi.c:299:9:    expected void volatile [noderef] __iomem *addr
drivers/acpi/cppc_acpi.c:299:9:    got unsigned short *
drivers/acpi/cppc_acpi.c:302:9: warning: incorrect type in argument 2 (different address spaces)
drivers/acpi/cppc_acpi.c:302:9:    expected void volatile [noderef] __iomem *addr
drivers/acpi/cppc_acpi.c:302:9:    got unsigned short *
Signed-off-by: NIonela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The cppc_cpudata per-cpu storage was inefficient (1) additional to causing
functional issues (2) when CPUs are hotplugged out, due to per-cpu data
being improperly initialised.

(1) The amount of information needed for CPPC performance control in its
    cpufreq driver depends on the domain (PSD) coordination type:

    ANY:    One set of CPPC control and capability data (e.g desired
            performance, highest/lowest performance, etc) applies to all
            CPUs in the domain.

    ALL:    Same as ANY. To be noted that this type is not currently
            supported. When supported, information about which CPUs
            belong to a domain is needed in order for frequency change
            requests to be sent to each of them.

    HW:     It's necessary to store CPPC control and capability
            information for all the CPUs. HW will then coordinate the
            performance state based on their limitations and requests.

    NONE:   Same as HW. No HW coordination is expected.

    Despite this, the previous initialisation code would indiscriminately
    allocate memory for all CPUs (all_cpu_data) and unnecessarily
    duplicate performance capabilities and the domain sharing mask and type
    for each possible CPU.

(2) With the current per-cpu structure, when having ANY coordination,
    the cppc_cpudata cpu information is not initialised (will remain 0)
    for all CPUs in a policy, other than policy->cpu. When policy->cpu is
    hotplugged out, the driver will incorrectly use the uninitialised (0)
    value of the other CPUs when making frequency changes. Additionally,
    the previous values stored in the perf_ctrls.desired_perf will be
    lost when policy->cpu changes.

Therefore replace the array of per cpu data with a list. The memory for
each structure is allocated at policy init, where a single structure
can be allocated per policy, not per cpu. In order to accommodate the
struct list_head node in the cppc_cpudata structure, the now unused cpu
and cur_policy variables are removed.

For example, on a arm64 Juno platform with 6 CPUs: (0, 1, 2, 3) in PSD1,
(4, 5) in PSD2 - ANY coordination, the memory allocation comparison shows:

Before patch:

 - ANY coordination:
   total    slack      req alloc/free  caller
       0        0        0     0/1     _kernel_size_le_hi32+0x0xffff800008ff7810
       0        0        0     0/6     _kernel_size_le_hi32+0x0xffff800008ff7808
     128       80       48     1/0     _kernel_size_le_hi32+0x0xffff800008ffc070
     768        0      768     6/0     _kernel_size_le_hi32+0x0xffff800008ffc0e4

After patch:

 - ANY coordination:
    total    slack      req alloc/free  caller
     256        0      256     2/0     _kernel_size_le_hi32+0x0xffff800008fed410
       0        0        0     0/2     _kernel_size_le_hi32+0x0xffff800008fed274

Additional notes:
 - A pointer to the policy's cppc_cpudata is stored in policy->driver_data
 - Driver registration is skipped if _CPC entries are not present.
Signed-off-by: NIonela Voinescu <ionela.voinescu@arm.com>
Tested-by: NMian Yousaf Kaukab <ykaukab@suse.de>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

For errors parsing the _PSD domains, a separate domain is returned for
each CPU in the failed _PSD domain with no coordination (as per previous
comment). But contrary to the intention, the code was setting
CPUFREQ_SHARED_TYPE_ALL as coordination type.

Change shared_type to CPUFREQ_SHARED_TYPE_NONE in case of errors parsing
the domain information. The function still returns the error and the caller
is free to bail out the domain initialisation altogether in that case.

Given that both functions return domains with a single CPU, this change
does not affect the functionality, but clarifies the intention.
Signed-off-by: NIonela Voinescu <ionela.voinescu@arm.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
[ rjw: Subject edit ]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This is the first pass in creating the ability to calculate the
frequency invariance on AMD systems. This approach uses the CPPC
highest performance and nominal performance values that range from
0 - 255 instead of a high and base frquency. This is because we do
not have the ability on AMD to get a highest frequency value.

On AMD systems the highest performance and nominal performance
vaues do correspond to the highest and base frequencies for the system
so using them should produce an appropriate ratio but some tweaking
is likely necessary.

Due to CPPC being initialized later in boot than when the frequency
invariant calculation is currently made, I had to create a callback
from the CPPC init code to do the calculation after we have CPPC
data.

Special thanks to "kernel test robot <lkp@intel.com>" for reporting that
compilation of drivers/acpi/cppc_acpi.c is conditional to
CONFIG_ACPI_CPPC_LIB, not just CONFIG_ACPI.

[ ggherdovich@suse.cz: made safe under CPU hotplug, edited changelog. ]
Signed-off-by: NNathan Fontenot <nathan.fontenot@amd.com>
Signed-off-by: NGiovanni Gherdovich <ggherdovich@suse.cz>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20201112182614.10700-2-ggherdovich@suse.cz

kobject_init_and_add() takes reference even when it fails.
If this function returns an error, kobject_put() must be called to
properly clean up the memory associated with the object. Previous
commit "b8eb7183" fixed a similar problem.

Fixes: 158c998e ("ACPI / CPPC: add sysfs support to compute delivered performance")
Signed-off-by: NQiushi Wu <wu000273@umn.edu>
Cc: 4.10+ <stable@vger.kernel.org> # 4.10+
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Fix the following sparse warnings:

drivers/acpi/cppc_acpi.c:353:20: warning: symbol 'cppc_mbox_cl' was not declared. Should it be static?
drivers/acpi/cppc_acpi.c:600:5: warning: symbol 'pcc_data_alloc' was not declared. Should it be static?
Reported-by: NHulk Robot <hulkci@huawei.com>
Signed-off-by: NZou Wei <zou_wei@huawei.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

In acpi_get_psd_map() variable all_cpu_data[] can't be NULL and variable
match_cpc_ptr has been checked before, no need check again at the end of
the funchtion.

Some additional optimizations can be made on top of that.
Signed-off-by: NLiguang Zhang <zhangliguang@linux.alibaba.com>
[ rjw: Subject & changelog ]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

When enabling KASAN and DEBUG_TEST_DRIVER_REMOVE, I find this KASAN
warning:

[   20.872057] BUG: KASAN: use-after-free in pcc_data_alloc+0x40/0xb8
[   20.878226] Read of size 4 at addr ffff00236cdeb684 by task swapper/0/1
[   20.884826]
[   20.886309] CPU: 19 PID: 1 Comm: swapper/0 Not tainted 5.4.0-rc1-00009-ge7f7df3db5bf-dirty #289
[   20.894994] Hardware name: Huawei D06 /D06, BIOS Hisilicon D06 UEFI RC0 - V1.16.01 03/15/2019
[   20.903505] Call trace:
[   20.905942]  dump_backtrace+0x0/0x200
[   20.909593]  show_stack+0x14/0x20
[   20.912899]  dump_stack+0xd4/0x130
[   20.916291]  print_address_description.isra.9+0x6c/0x3b8
[   20.921592]  __kasan_report+0x12c/0x23c
[   20.925417]  kasan_report+0xc/0x18
[   20.928808]  __asan_load4+0x94/0xb8
[   20.932286]  pcc_data_alloc+0x40/0xb8
[   20.935938]  acpi_cppc_processor_probe+0x4e8/0xb08
[   20.940717]  __acpi_processor_start+0x48/0xb0
[   20.945062]  acpi_processor_start+0x40/0x60
[   20.949235]  really_probe+0x118/0x548
[   20.952887]  driver_probe_device+0x7c/0x148
[   20.957059]  device_driver_attach+0x94/0xa0
[   20.961231]  __driver_attach+0xa4/0x110
[   20.965055]  bus_for_each_dev+0xe8/0x158
[   20.968966]  driver_attach+0x30/0x40
[   20.972531]  bus_add_driver+0x234/0x2f0
[   20.976356]  driver_register+0xbc/0x1d0
[   20.980182]  acpi_processor_driver_init+0x40/0xe4
[   20.984875]  do_one_initcall+0xb4/0x254
[   20.988700]  kernel_init_freeable+0x24c/0x2f8
[   20.993047]  kernel_init+0x10/0x118
[   20.996524]  ret_from_fork+0x10/0x18
[   21.000087]
[   21.001567] Allocated by task 1:
[   21.004785]  save_stack+0x28/0xc8
[   21.008089]  __kasan_kmalloc.isra.9+0xbc/0xd8
[   21.012435]  kasan_kmalloc+0xc/0x18
[   21.015913]  pcc_data_alloc+0x94/0xb8
[   21.019564]  acpi_cppc_processor_probe+0x4e8/0xb08
[   21.024343]  __acpi_processor_start+0x48/0xb0
[   21.028689]  acpi_processor_start+0x40/0x60
[   21.032860]  really_probe+0x118/0x548
[   21.036512]  driver_probe_device+0x7c/0x148
[   21.040684]  device_driver_attach+0x94/0xa0
[   21.044855]  __driver_attach+0xa4/0x110
[   21.048680]  bus_for_each_dev+0xe8/0x158
[   21.052591]  driver_attach+0x30/0x40
[   21.056155]  bus_add_driver+0x234/0x2f0
[   21.059980]  driver_register+0xbc/0x1d0
[   21.063805]  acpi_processor_driver_init+0x40/0xe4
[   21.068497]  do_one_initcall+0xb4/0x254
[   21.072322]  kernel_init_freeable+0x24c/0x2f8
[   21.076667]  kernel_init+0x10/0x118
[   21.080144]  ret_from_fork+0x10/0x18
[   21.083707]
[   21.085186] Freed by task 1:
[   21.088056]  save_stack+0x28/0xc8
[   21.091360]  __kasan_slab_free+0x118/0x180
[   21.095445]  kasan_slab_free+0x10/0x18
[   21.099183]  kfree+0x80/0x268
[   21.102139]  acpi_cppc_processor_exit+0x1a8/0x1b8
[   21.106832]  acpi_processor_stop+0x70/0x80
[   21.110917]  really_probe+0x174/0x548
[   21.114568]  driver_probe_device+0x7c/0x148
[   21.118740]  device_driver_attach+0x94/0xa0
[   21.122912]  __driver_attach+0xa4/0x110
[   21.126736]  bus_for_each_dev+0xe8/0x158
[   21.130648]  driver_attach+0x30/0x40
[   21.134212]  bus_add_driver+0x234/0x2f0
[   21.0x10/0x18
[   21.161764]
[   21.163244] The buggy address belongs to the object at ffff00236cdeb600
[   21.163244]  which belongs to the cache kmalloc-256 of size 256
[   21.175750] The buggy address is located 132 bytes inside of
[   21.175750]  256-byte region [ffff00236cdeb600, ffff00236cdeb700)
[   21.187473] The buggy address belongs to the page:
[   21.192254] page:fffffe008d937a00 refcount:1 mapcount:0 mapping:ffff002370c0fa00 index:0x0 compound_mapcount: 0
[   21.202331] flags: 0x1ffff00000010200(slab|head)
[   21.206940] raw: 1ffff00000010200 dead000000000100 dead000000000122 ffff002370c0fa00
[   21.214671] raw: 0000000000000000 00000000802a002a 00000001ffffffff 0000000000000000
[   21.222400] page dumped because: kasan: bad access detected
[   21.227959]
[   21.229438] Memory state around the buggy address:
[   21.234218]  ffff00236cdeb580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   21.241427]  ffff00236cdeb600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[   21.248637] >ffff00236cdeb680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[   21.255845]                    ^
[   21.259062]  ffff00236cdeb700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   21.266272]  ffff00236cdeb780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[   21.273480] ==================================================================

It seems that global pcc_data[pcc_ss_id] can be freed in
acpi_cppc_processor_exit(), but we may later reference this value, so
NULLify it when freed.

Also remove the useless setting of data "pcc_channel_acquired", which
we're about to free.

Fixes: 85b1407b ("ACPI / CPPC: Make CPPC ACPI driver aware of PCC subspace IDs")
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Cc: 4.15+ <stable@vger.kernel.org> # 4.15+
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

According to the ACPI 6.3 specification, the _PSD method is optional
when using CPPC.  The underlying assumption is that each CPU can change
frequency independently from all other CPUs; _PSD is provided to tell
the OS that some processors can NOT do that.

However, the acpi_get_psd() function returns ENODEV if there is no _PSD
method present, or an ACPI error status if an error occurs when evaluating
_PSD, if present.  This makes _PSD mandatory when using CPPC, in violation
of the specification, and only on Linux.

This has forced some firmware writers to provide a dummy _PSD, even though
it is irrelevant, but only because Linux requires it; other OSPMs follow
the spec.  We really do not want to have OS specific ACPI tables, though.

So, correct acpi_get_psd() so that it does not return an error if there
is no _PSD method present, but does return a failure when the method can
not be executed properly.  This allows _PSD to be optional as it should
be.
Signed-off-by: NAl Stone <ahs3@redhat.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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 version 2 of the license

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 315 file(s).
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NAllison Randal <allison@lohutok.net>
Reviewed-by: NArmijn Hemel <armijn@tjaldur.nl>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531190115.503150771@linutronix.deSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Fix some misspellings in comments.  No functional change intended.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

As per the ACPI specification, "Guaranteed Performance Register" is
a "Buffer" field and it cannot be "Integer", so treat the "Integer"
type for "Guaranteed Performance Register" field as invalid and
ignore its value in that case.

Also save one cpc_read() call when "Guaranteed Performance Register"
is not present, which means a register defined as:
"Register(SystemMemory, 0, 0, 0, 0)".

Fixes: 29523f09 ("ACPI / CPPC: Add support for guaranteed performance")
Suggested-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: 4.20+ <stable@vger.kernel.org> # 4.20+
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>