Extend the perf notification report to include pre-calculated frequencies
corresponding to the reported limits/levels event; such frequencies are
properly computed based on the stored known OPPs information taking into
consideration if the current operating mode is level indexed or not.
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20240212123233.1230090-12-cristian.marussi@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Store all the discovered OPPs into the XArray opps_by_lvl even when
level_indexing mode is not used, since it comes handy to easily retrieve
OPPs by level.
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20240212123233.1230090-11-cristian.marussi@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Add a preliminary check to verify if the performance related notify
enable commands are supported at all by the SCMI platform, and then
provide the callback needed to allow the core SCMI notification
subsytem to do a fine-grain check if a specific resource domain
supports notifications.
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20240212123233.1230090-4-cristian.marussi@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
When (sustained_freq_khz * 1000) is less than sustained_perf_level, the
multiplier will be less than 1 and hence rounded down as 0. Similarly if
it is not multiple of sustained_perf_level the dom_info->mult_factor will
contain rounded down value and will end up impacting all the frequency
calculations done using it.
Add warning if and when the domain frequency multiplier is 0 or rounded
down so that it gives a clue to get the firmware tables fixed.
Suggested-by: Pierre Gondois <Pierre.Gondois@arm.com>
Reviewed-by: Pierre Gondois <pierre.gondois@arm.com>
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20240119152338.3047620-1-sudeep.holla@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
When storing opps by level or index use xa_insert() instead of xa_store()
and add error-checking to spot bad duplicates indexes possibly wrongly
provided by the platform firmware.
Fixes: 31c7c1397a ("firmware: arm_scmi: Add v3.2 perf level indexing mode support")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20240108185050.1628687-1-cristian.marussi@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
A new drivers/cache/ subsystem is added to contain drivers for abstracting
cache flush methods on riscv and potentially others, as this is needed for
handling non-coherent DMA but several SoCs require nonstandard hardware
methods for it.
op-tee gains support for asynchronous notification with FF-A, as well
as support for a system thread for executing in secure world.
The tee, reset, bus, memory and scmi subsystems have a couple of minor
updates.
Platform specific soc driver changes include:
- Samsung Exynos gains driver support for Google GS101 (Tensor G1)
across multiple subsystems
- Qualcomm Snapdragon gains support for SM8650 and X1E along with
added features for some other SoCs
- Mediatek adds support for "Smart Voltage Scaling" on MT8186 and MT8195,
and driver support for MT8188 along with some code refactoring.
- Microchip Polarfire FPGA support for "Auto Update" of the FPGA bitstream
- Apple M1 mailbox driver is rewritten into a SoC driver
- minor updates on amlogic, mvebu, ti, zynq, imx, renesas and hisilicon
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Merge tag 'soc-drivers-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull SoC driver updates from Arnd Bergmann:
"A new drivers/cache/ subsystem is added to contain drivers for
abstracting cache flush methods on riscv and potentially others, as
this is needed for handling non-coherent DMA but several SoCs require
nonstandard hardware methods for it.
op-tee gains support for asynchronous notification with FF-A, as well
as support for a system thread for executing in secure world.
The tee, reset, bus, memory and scmi subsystems have a couple of minor
updates.
Platform specific soc driver changes include:
- Samsung Exynos gains driver support for Google GS101 (Tensor G1)
across multiple subsystems
- Qualcomm Snapdragon gains support for SM8650 and X1E along with
added features for some other SoCs
- Mediatek adds support for "Smart Voltage Scaling" on MT8186 and
MT8195, and driver support for MT8188 along with some code
refactoring.
- Microchip Polarfire FPGA support for "Auto Update" of the FPGA
bitstream
- Apple M1 mailbox driver is rewritten into a SoC driver
- minor updates on amlogic, mvebu, ti, zynq, imx, renesas and
hisilicon"
* tag 'soc-drivers-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (189 commits)
memory: ti-emif-pm: Convert to platform remove callback returning void
memory: ti-aemif: Convert to platform remove callback returning void
memory: tegra210-emc: Convert to platform remove callback returning void
memory: tegra186-emc: Convert to platform remove callback returning void
memory: stm32-fmc2-ebi: Convert to platform remove callback returning void
memory: exynos5422-dmc: Convert to platform remove callback returning void
memory: renesas-rpc-if: Convert to platform remove callback returning void
memory: omap-gpmc: Convert to platform remove callback returning void
memory: mtk-smi: Convert to platform remove callback returning void
memory: jz4780-nemc: Convert to platform remove callback returning void
memory: fsl_ifc: Convert to platform remove callback returning void
memory: fsl-corenet-cf: Convert to platform remove callback returning void
memory: emif: Convert to platform remove callback returning void
memory: brcmstb_memc: Convert to platform remove callback returning void
memory: brcmstb_dpfe: Convert to platform remove callback returning void
soc: qcom: llcc: Fix LLCC_TRP_ATTR2_CFGn offset
firmware: qcom: qseecom: fix memory leaks in error paths
dt-bindings: clock: google,gs101: rename CMU_TOP gate defines
soc: qcom: llcc: Fix typo in kernel-doc
dt-bindings: soc: qcom,aoss-qmp: document the X1E80100 Always-On Subsystem side channel
...
The multiplier is already promoted to unsigned long, however the
frequency calculations done when using level indexing mode doesn't
use the multiplier computed. It instead hardcodes the multiplier
value of 1000 at all the usage sites.
Clean that up by assigning the multiplier value of 1000 when using
the perf level indexing mode and update the frequency calculations to
use the multiplier instead. It should fix the possible frequency
truncation for all the values greater than or equal to 4GHz on 64-bit
machines.
Fixes: 31c7c1397a ("firmware: arm_scmi: Add v3.2 perf level indexing mode support")
Reported-by: Sibi Sankar <quic_sibis@quicinc.com>
Closes: https://lore.kernel.org/all/20231129065748.19871-3-quic_sibis@quicinc.com/
Cc: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20231130204343.503076-2-sudeep.holla@arm.com
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Fix the possible frequency truncation for all values equal to or greater
4GHz on 64bit machines by updating the multiplier 'mult_factor' to
'unsigned long' type. It is also possible that the multiplier itself can
be greater than or equal to 2^32. So we need to also fix the equation
computing the value of the multiplier.
Fixes: a9e3fbfaa0 ("firmware: arm_scmi: add initial support for performance protocol")
Reported-by: Sibi Sankar <quic_sibis@quicinc.com>
Closes: https://lore.kernel.org/all/20231129065748.19871-3-quic_sibis@quicinc.com/
Cc: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20231130204343.503076-1-sudeep.holla@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Platform and agent supported protocols versions do not necessarily match.
When talking to an older SCMI platform, supporting only older protocol
versions, the kernel SCMI agent will downgrade the version of the used
protocol to match the platform and avoid compatibility issues.
In the case where the kernel/OSPM agent happens to communicate with a
newer platform which can support newer protocol versions unknown to
the agent, and potentially backward incompatible, the agent currently
carries on, silently, in a best-effort approach.
Note that the SCMI specification doesn't provide means to explicitly
detect the protocol versions used by the agents, neither it is required
to support multiple, older, protocol versions.
Add an explicit protocol version check to let the agent detect when this
version mismatch happens and warn the user about this condition.
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20231201135858.2367651-1-cristian.marussi@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The number of opps on certain variants of the X1E80100 SoC are greater
than current maximum of 16, so increase the MAX_OPP count to 32 (next
power of 2) to accommodate that.
Signed-off-by: Sibi Sankar <quic_sibis@quicinc.com>
Link: https://lore.kernel.org/r/20231129065748.19871-4-quic_sibis@quicinc.com
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The scmi_perf_domain_lookup requires the protocol handle to have the
private data set, which is yet to happen during the fastchannel init
scenario. This results in a NULL pointer dereference. Fix this by using
the pre-populated perf_dom_info to pass on the required information
instead.
| scmi_perf_protocol_init+0x434/0x678
| scmi_get_protocol_instance+0x168/0x29c
| scmi_devres_protocol_instance_get+0x50/0xa0
| scmi_devm_protocol_get+0x20/0x50
| scmi_cpufreq_probe+0x34/0xd4
| scmi_dev_probe+0x28/0x3c
| really_probe+0x148/0x2ac
| __driver_probe_device+0x78/0x12c
| driver_probe_device+0x40/0x160
| __device_attach_driver+0xb8/0x134
| bus_for_each_drv+0x80/0xdc
| __device_attach+0xa8/0x1b0
| device_initial_probe+0x14/0x20
| bus_probe_device+0xa8/0xac
| device_add+0x5cc/0x778
| device_register+0x20/0x30
| __scmi_device_create.part.0+0xec/0x1cc
| scmi_device_create+0x180/0x1c4
| scmi_create_protocol_devices+0x4c/0xb0
| scmi_probe+0x660/0x738
| platform_probe+0x68/0xdc
| really_probe+0x148/0x2ac
| __driver_probe_device+0x78/0x12c
| driver_probe_device+0x40/0x160
| __device_attach_driver+0xb8/0x134
| bus_for_each_drv+0x80/0xdc
| __device_attach+0xa8/0x1b0
| device_initial_probe+0x14/0x20
| bus_probe_device+0xa8/0xac
| deferred_probe_work_func+0x88/0xc0
| process_one_work+0x13c/0x264
| worker_thread+0x32c/0x438
| kthread+0x118/0x11c
| ret_from_fork+0x10/0x20
Fixes: 619bc6e034 ("firmware: arm_scmi: Populate fastchannel info only if set operations are allowed")
Signed-off-by: Sibi Sankar <quic_sibis@quicinc.com>
Link: https://lore.kernel.org/r/20231129065748.19871-2-quic_sibis@quicinc.com
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Some recently added SCMI protocols needs an additional flags parameter to
be able to properly configure the command used to query the extended name
of a resource.
Modify extended_name_get helper accordingly.
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20231114145449.3136412-1-cristian.marussi@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Certain SCMI performance domains may have restrictions on the set level
and/or limits operation. If the SCMI domain supports fastchannel and the
set operations are not allowed, then any attempts to fetch the fastchannel
information for set level and/or limits operation will result in the
SCMI platform returning SCMI_ERR_SUPPORT. However, since this information
about the domain is already known to the agent(OSPM here) obtained via
PERF_DOMAIN_ATTRIBUTES, the agent(OSPM) can avoid calls to the firmware
trying to fetch the fastchannel information for the same.
Add those checks and skip querying the fastchannel information from the
firmware based on the information collected during the domain enumeration
stage.
Link: https://lore.kernel.org/r/20231113143252.37160-1-sudeep.holla@arm.com
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Certain SCMI performance domains may have restrictions on the set level
and/or limits operation. If the set level/limits are performed by an
agent who is not allowed to do so may get SCMI_ERR_SUPPORT. However,
since this information about the domain is already known to the
agent(OSPM here) obtained via PERF_DOMAIN_ATTRIBUTES, the agent(OSPM)
can avoid making PERF_LEVEL_SET and PERF_LIMITS_SET calls to the firmware.
Add those checks and return -ENOTSUPP to the caller without interacting
with the firmware based on the information collected during the domain
enumeration stage.
Signed-off-by: xinglong.yang <xinglong.yang@cixtech.com>
Link: https://lore.kernel.org/r/20231109082855.472681-1-xinglong.yang@cixtech.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Main additions this time include:
1. SCMI v3.2 clock configuration support:
This helps to retrieve the enabled state of a clock as well as allow
to set OEM specific clock configurations.
2. Support for generic performance scaling(DVFS):
The current SCMI DVFS support is limited to the CPUs in the kernel.
This extension enables it to used for all kind of devices and not
only for the CPUs. It updates the SCMI cpufreq to utilize the power
domain bindings. It also adds a more generic SCMI performance domain
based on the genpd framework that as be used for all the non-CPU
devices.
3. Extend the generic performance scaling(DVFS) support for firmware
driver OPPs:
Consumer drivers for devices that are attached to the SCMI performance
domain can't make use of the current OPP library to scale performance
as the OPPs are firmware driven and often obtained from the firmware
rather than the device tree. These changes extend the generic OPP
and genpd PM domain frameworks to identify and utilise these firmware
driven OPPs.
4. SCMI v3.2 clock parent support:
This enables the support for discovering and changing parent clocks
and extending the SCMI clk driver to use the same.
5. Qualcom SMC/HVC transport support:
The Qualcomm virtual platforms require capability id in the hypervisor
call to identify which doorbell to assert when supporting multiple
SMC/HVC based SCMI transport channels. Extra parameter is added to
support the same and the same is obtained at the fixed address in the
shared memory which is initialised by the firmware.
6. Move the existing SCMI power domain driver under drivers/pmdomain
Apart from the above main changes, it also include couple of minor fixes
and cosmetic reworks.
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Merge tag 'scmi-updates-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux into soc/drivers
Arm SCMI updates for v6.7
Main additions this time include:
1. SCMI v3.2 clock configuration support:
This helps to retrieve the enabled state of a clock as well as allow
to set OEM specific clock configurations.
2. Support for generic performance scaling(DVFS):
The current SCMI DVFS support is limited to the CPUs in the kernel.
This extension enables it to used for all kind of devices and not
only for the CPUs. It updates the SCMI cpufreq to utilize the power
domain bindings. It also adds a more generic SCMI performance domain
based on the genpd framework that as be used for all the non-CPU
devices.
3. Extend the generic performance scaling(DVFS) support for firmware
driver OPPs:
Consumer drivers for devices that are attached to the SCMI performance
domain can't make use of the current OPP library to scale performance
as the OPPs are firmware driven and often obtained from the firmware
rather than the device tree. These changes extend the generic OPP
and genpd PM domain frameworks to identify and utilise these firmware
driven OPPs.
4. SCMI v3.2 clock parent support:
This enables the support for discovering and changing parent clocks
and extending the SCMI clk driver to use the same.
5. Qualcom SMC/HVC transport support:
The Qualcomm virtual platforms require capability id in the hypervisor
call to identify which doorbell to assert when supporting multiple
SMC/HVC based SCMI transport channels. Extra parameter is added to
support the same and the same is obtained at the fixed address in the
shared memory which is initialised by the firmware.
6. Move the existing SCMI power domain driver under drivers/pmdomain
Apart from the above main changes, it also include couple of minor fixes
and cosmetic reworks.
* tag 'scmi-updates-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux: (37 commits)
firmware: arm_scmi: Add qcom smc/hvc transport support
dt-bindings: arm: Add new compatible for smc/hvc transport for SCMI
firmware: arm_scmi: Convert u32 to unsigned long to align with arm_smccc_1_1_invoke()
clk: scmi: Add support for clock {set,get}_parent
firmware: arm_scmi: Add support for clock parents
clk: scmi: Free scmi_clk allocated when the clocks with invalid info are skipped
firmware: arm_scpi: Use device_get_match_data()
firmware: arm_scmi: Add generic OPP support to the SCMI performance domain
firmware: arm_scmi: Specify the performance level when adding an OPP
firmware: arm_scmi: Simplify error path in scmi_dvfs_device_opps_add()
OPP: Extend support for the opp-level beyond required-opps
OPP: Switch to use dev_pm_domain_set_performance_state()
OPP: Extend dev_pm_opp_data with a level
OPP: Add dev_pm_opp_add_dynamic() to allow more flexibility
PM: domains: Implement the ->set_performance_state() callback for genpd
PM: domains: Introduce dev_pm_domain_set_performance_state()
firmware: arm_scmi: Rename scmi_{msg_,}clock_config_{get,set}_{2,21}
firmware: arm_scmi: Do not use !! on boolean when setting msg->flags
firmware: arm_scmi: Move power-domain driver to the pmdomain dir
pmdomain: arm: Add the SCMI performance domain
...
Link: https://lore.kernel.org/r/20231010124347.1620040-1-sudeep.holla@arm.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
To enable the performance level to be used for OPPs, let's convert into
using the dev_pm_opp_add_dynamic() API when creating them. This will be
particularly useful for the SCMI performance domain, as shown through
subsequent changes.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20230925131715.138411-9-ulf.hansson@linaro.org
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Let's simplify the code in scmi_dvfs_device_opps_add() by using
dev_pm_opp_remove_all_dynamic() in the error path.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20230925131715.138411-8-ulf.hansson@linaro.org
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
There are no longer any users of the ->device_domain_id() ops in the
scmi_perf_proto_ops, therefore let's remove it.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20230825112633.236607-6-ulf.hansson@linaro.org
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Most scmi_perf_proto_ops are already using an "u32 domain" as an
in-parameter to indicate what performance domain we shall operate upon.
However, some of the ops are using a "struct device *dev", which means that
an additional OF parsing is needed each time the perf ops gets called, to
find the corresponding domain-id.
To avoid the above, but also to make the code more consistent, let's
replace the in-parameter "struct device *dev" with an "u32 domain". Note
that, this requires us to make some corresponding changes to the scmi
cpufreq driver, so let's do that too.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://lore.kernel.org/r/20230825112633.236607-5-ulf.hansson@linaro.org
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Similar to other protocol ops, it's useful for an scmi module driver to get
some generic information of a performance domain. Therefore, let's add a
new callback to provide this information. The information is currently
limited to the name of the performance domain and whether the set-level
operation is supported, although this can easily be extended if we find the
need for it.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20230825112633.236607-3-ulf.hansson@linaro.org
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Similar to other protocol ops, it's useful for an scmi module driver to get
the number of supported performance domains, hence let's make this
available by adding a new perf protocol callback. Note that, a user is
being added from subsequent changes.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20230825112633.236607-2-ulf.hansson@linaro.org
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The perf power scale value would currently be reported as bogowatts if the
platform firmware supports microwatt power scale and meets the perf major
version requirements. Fix this by populating version information in the
driver private data before the call to protocol attributes is made.
CC: Chandra Sekhar Lingutla <quic_lingutla@quicinc.com>
Fixes: 3630cd8130 ("firmware: arm_scmi: Add SCMI v3.1 perf power-cost in microwatts")
Signed-off-by: Sibi Sankar <quic_sibis@quicinc.com>
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20230811204818.30928-1-quic_sibis@quicinc.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
SCMI v3.2 adds PERF protocol support to optionally define performance
domains that cannot be represented on a linear scale; the platform firmware
can declare the performance levels of a domain as being 'level indexed' and
provide an indicative frequency associated to each of those levels, with
such indexes not required anymore to be contiguous nor to satisfy any
linear-scaling constraint: when level-indexing is available for a domain,
the platform will expect to deal with SCMI requests using indexes instead
of performance levels for that domain.
Add level-indexing mode support to the PERF protocol implementation while
maintaining unchanged the protocol operations interface exposed by PERF;
all the required mapping from performamce levels/frequencies to the
corresponding level indexes is carried out transparently by the core PERF
protocol support: as a consequence no change is either required in any
SCMI driver using the PERF protocol, even when using level indexing.
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20230717161246.1761777-3-cristian.marussi@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
- Make cpufreq_show_cpus() more straightforward (Viresh Kumar).
- Drop unnecessary CPU hotplug locking from store() used by cpufreq
sysfs attributes (Viresh Kumar).
- Make the ACPI cpufreq driver support the boost control interface on
Zhaoxin/Centaur processors (Tony W Wang-oc).
- Print a warning message on attempts to free an active cpufreq policy
which should never happen (Viresh Kumar).
- Fix grammar in the Kconfig help text for the loongson2 cpufreq
driver (Randy Dunlap).
- Use cpumask_var_t for an on-stack CPU mask in the ondemand cpufreq
governor (Zhao Liu).
- Add trace points for guest_halt_poll_ns grow/shrink to the haltpoll
cpuidle driver (Eiichi Tsukata).
- Modify intel_idle to treat C1 and C1E as independent idle states on
Sapphire Rapids (Artem Bityutskiy).
- Extend support for wakeirq to callback wrappers used during system
suspend and resume (Ulf Hansson).
- Defer waiting for device probe before loading a hibernation image
till the first actual device access to avoid possible deadlocks
reported by syzbot (Tetsuo Handa).
- Unify device_init_wakeup() for PM_SLEEP and !PM_SLEEP (Bjorn
Helgaas).
- Add Raptor Lake-P to the list of processors supported by the Intel
RAPL driver (George D Sworo).
- Add Alder Lake-N and Raptor Lake-P to the list of processors for
which Power Limit4 is supported in the Intel RAPL driver (Sumeet
Pawnikar).
- Make pm_genpd_remove() check genpd_debugfs_dir against NULL before
attempting to remove it (Hsin-Yi Wang).
- Change the Energy Model code to represent power in micro-Watts and
adjust its users accordingly (Lukasz Luba).
- Add new devfreq driver for Mediatek CCI (Cache Coherent
Interconnect) (Johnson Wang).
- Convert the Samsung Exynos SoC Bus bindings to DT schema of
exynos-bus.c (Krzysztof Kozlowski).
- Address kernel-doc warnings by adding the description for unused
fucntion parameters in devfreq core (Mauro Carvalho Chehab).
- Use NULL to pass a null pointer rather than zero according to the
function propotype in imx-bus.c (Colin Ian King).
- Print error message instead of error interger value in
tegra30-devfreq.c (Dmitry Osipenko).
- Add checks to prevent setting negative frequency QoS limits for
CPUs (Shivnandan Kumar).
- Update the pm-graph suite of utilities to the latest revision 5.9
including multiple improvements (Todd Brandt).
- Drop pme_interrupt reference from the PCI power management
documentation (Mario Limonciello).
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Merge tag 'pm-5.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"These are mostly minor improvements all over including new CPU IDs for
the Intel RAPL driver, an Energy Model rework to use micro-Watt as the
power unit, cpufreq fixes and cleanus, cpuidle updates, devfreq
updates, documentation cleanups and a new version of the pm-graph
suite of utilities.
Specifics:
- Make cpufreq_show_cpus() more straightforward (Viresh Kumar).
- Drop unnecessary CPU hotplug locking from store() used by cpufreq
sysfs attributes (Viresh Kumar).
- Make the ACPI cpufreq driver support the boost control interface on
Zhaoxin/Centaur processors (Tony W Wang-oc).
- Print a warning message on attempts to free an active cpufreq
policy which should never happen (Viresh Kumar).
- Fix grammar in the Kconfig help text for the loongson2 cpufreq
driver (Randy Dunlap).
- Use cpumask_var_t for an on-stack CPU mask in the ondemand cpufreq
governor (Zhao Liu).
- Add trace points for guest_halt_poll_ns grow/shrink to the haltpoll
cpuidle driver (Eiichi Tsukata).
- Modify intel_idle to treat C1 and C1E as independent idle states on
Sapphire Rapids (Artem Bityutskiy).
- Extend support for wakeirq to callback wrappers used during system
suspend and resume (Ulf Hansson).
- Defer waiting for device probe before loading a hibernation image
till the first actual device access to avoid possible deadlocks
reported by syzbot (Tetsuo Handa).
- Unify device_init_wakeup() for PM_SLEEP and !PM_SLEEP (Bjorn
Helgaas).
- Add Raptor Lake-P to the list of processors supported by the Intel
RAPL driver (George D Sworo).
- Add Alder Lake-N and Raptor Lake-P to the list of processors for
which Power Limit4 is supported in the Intel RAPL driver (Sumeet
Pawnikar).
- Make pm_genpd_remove() check genpd_debugfs_dir against NULL before
attempting to remove it (Hsin-Yi Wang).
- Change the Energy Model code to represent power in micro-Watts and
adjust its users accordingly (Lukasz Luba).
- Add new devfreq driver for Mediatek CCI (Cache Coherent
Interconnect) (Johnson Wang).
- Convert the Samsung Exynos SoC Bus bindings to DT schema of
exynos-bus.c (Krzysztof Kozlowski).
- Address kernel-doc warnings by adding the description for unused
function parameters in devfreq core (Mauro Carvalho Chehab).
- Use NULL to pass a null pointer rather than zero according to the
function propotype in imx-bus.c (Colin Ian King).
- Print error message instead of error interger value in
tegra30-devfreq.c (Dmitry Osipenko).
- Add checks to prevent setting negative frequency QoS limits for
CPUs (Shivnandan Kumar).
- Update the pm-graph suite of utilities to the latest revision 5.9
including multiple improvements (Todd Brandt).
- Drop pme_interrupt reference from the PCI power management
documentation (Mario Limonciello)"
* tag 'pm-5.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (27 commits)
powercap: RAPL: Add Power Limit4 support for Alder Lake-N and Raptor Lake-P
PM: QoS: Add check to make sure CPU freq is non-negative
PM: hibernate: defer device probing when resuming from hibernation
intel_idle: make SPR C1 and C1E be independent
cpufreq: ondemand: Use cpumask_var_t for on-stack cpu mask
cpufreq: loongson2: fix Kconfig "its" grammar
pm-graph v5.9
cpufreq: Warn users while freeing active policy
cpufreq: scmi: Support the power scale in micro-Watts in SCMI v3.1
firmware: arm_scmi: Get detailed power scale from perf
Documentation: EM: Switch to micro-Watts scale
PM: EM: convert power field to micro-Watts precision and align drivers
PM / devfreq: tegra30: Add error message for devm_devfreq_add_device()
PM / devfreq: imx-bus: use NULL to pass a null pointer rather than zero
PM / devfreq: shut up kernel-doc warnings
dt-bindings: interconnect: samsung,exynos-bus: convert to dtschema
PM / devfreq: mediatek: Introduce MediaTek CCI devfreq driver
dt-bindings: interconnect: Add MediaTek CCI dt-bindings
PM: domains: Ensure genpd_debugfs_dir exists before remove
PM: runtime: Extend support for wakeirq for force_suspend|resume
...
In SCMI v3.1 the power scale can be in micro-Watts. The upper layers, e.g.
cpufreq and EM should handle received power values properly (upscale when
needed). Thus, provide an interface which allows to check what is the
scale for power values. The old interface allowed to distinguish between
bogo-Watts and milli-Watts only (which was good for older SCMI spec).
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Generalize existing fast channel support used in the perf protocol and
make it available to possibly any protocol refactoring the common code
into a couple of new scmi_proto_helpers_ops routines.
Make perf protocol use this new infrastructure.
No functional change.
Link: https://lore.kernel.org/r/20220704102241.2988447-4-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Commit b260fccaeb ("firmware: arm_scmi: Add SCMI v3.1 protocol extended
names support") moved all the name string buffers to use the extended buffer
size of 64 instead of the required 16 bytes. While that should be fine if
the firmware terminates the string before 16 bytes, there is possibility
of copying random data if the name is not NULL terminated by the firmware.
SCMI base protocol agent_name/vendor_id/sub_vendor_id are defined by the
specification as NULL-terminated ASCII strings up to 16-bytes in length.
The underlying buffers and message descriptors are currently bigger than
needed; resize them to fit only the strictly needed 16 bytes to avoid
any possible leaks when reading data from the firmware.
Change the size argument of strlcpy to use SCMI_SHORT_NAME_MAX_SIZE always
when dealing with short domain names, so as to limit the possibility that
an ill-formed non-NULL terminated short reply from the SCMI platform
firmware can leak stale content laying in the underlying transport shared
memory area.
While at that, convert all strings handling routines to use the preferred
strscpy.
Link: https://lore.kernel.org/r/20220608095530.497879-1-cristian.marussi@arm.com
Fixes: b260fccaeb ("firmware: arm_scmi: Add SCMI v3.1 protocol extended names support")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
While using SCMI iterators helpers a few local automatic variables are
defined but then used only as input for sizeof operators.
cppcheck is fooled to complain about this with:
| drivers/firmware/arm_scmi/sensors.c:341:48: warning: Variable 'msg' is
| not assigned a value. [unassignedVariable]
| struct scmi_msg_sensor_list_update_intervals *msg;
Even though this is an innocuos warning, since the uninitialized variable
is at the end never used in the reported cases, fix these occurences all
over SCMI stack to avoid keeping unneeded objects on the stack.
Link: https://lore.kernel.org/r/20220530115237.277077-1-cristian.marussi@arm.com
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Starting with SCMI v3.1, the PERFORMANCE_LIMITS_SET command allows a user
to request only one between max and min ranges to be changed, while leaving
the other untouched if set to zero in the request. Anyway SCMI v3.1 states
also explicitly that you cannot leave both of those unchanged (zeroed) when
issuing such command, so add a proper check for this condition.
Link: https://lore.kernel.org/r/20220330150551.2573938-23-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
[sudeep.holla: Dropped check for v3.0 and above to make the check
unconditional, updated the subject accordingly]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Add SCMI v3.1 internal support for parsing message attributes reporting
the capability of a performance domain to report power-cost in microwatts.
Link: https://lore.kernel.org/r/20220330150551.2573938-22-cristian.marussi@arm.com
Cc: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Using the common protocol helper implementation add support for all new
SCMIv3.1 extended names commands related to all protocols with the
exception of SENSOR_AXIS_GET_NAME.
Link: https://lore.kernel.org/r/20220330150551.2573938-12-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Move some SCMI protocol specific definitions from common.h into a the new
dedicated protocols.h header so that SCMI protocols core code can include
only what it needs; this is going to be useful to avoid the risk of growing
indefinitely the dimension of common.h, especially when introducing some
common protocols helper functions.
Header common.h will continue to be included by SCMI core and transport
layers.
Link: https://lore.kernel.org/r/20220330150551.2573938-10-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Bail out of protocol initialisation routine early when basic information
about protocol version and attributes could not be retrieved. Failing to
act this way can lead to a successfully initialized SCMI protocol which
is in fact not fully functional.
Link: https://lore.kernel.org/r/20220330150551.2573938-3-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Extend SCMI protocols accounting mechanism to address possible module
usage and add the support to possibly define new protocols as loadable
modules.
Keep the standard protocols built into the SCMI core.
Link: https://lore.kernel.org/r/20210316124903.35011-38-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Remove all the events registration code used to ease the transition to the
new interface based on protocol handles.
Link: https://lore.kernel.org/r/20210316124903.35011-35-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Now that all the SCMI driver users have been migrated to the new interface
remove the legacy interface and all the transient code.
Link: https://lore.kernel.org/r/20210316124903.35011-14-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Convert internals of protocol implementation to use protocol handles and
expose a new protocol operations interface for SCMI driver using the new
get/put common operations, while keeping the old handle->perf_ops still
around to ease transition.
Remove handle->perf_priv now unused.
Link: https://lore.kernel.org/r/20210316124903.35011-12-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Convert all refactored events registration routines to use protocol
handles.
In order to maintain bisectability and to allow protocols and drivers
to be later ported to the new protocol handle interface one by one,
introduce here also some transient code that will be removed later
in order to ease such transition.
Link: https://lore.kernel.org/r/20210316124903.35011-8-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Add a new refactored protocol events registration helper and invoke it
from the centralized initialization process triggered by get_ops() and
friends.
Also add a `get_num_sources` as a new optional callback amongst protocol
events operations. Finally remove events registration call-sites from
within the legacy protocol init routines.
Link: https://lore.kernel.org/r/20210316124903.35011-7-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Extend common protocol registration routines and provide some new generic
protocols get/put helpers that can track protocols usage and automatically
perform the proper initialization and de-initialization on demand when
required.
Convert all standard protocols to use this new registration scheme while
keeping them all still using the usual initialization logic bound to SCMI
devices probing.
Link: https://lore.kernel.org/r/20210316124903.35011-2-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Add a new interface to the existing perf_ops and export the information
about the power values scale.
This would be used by the cpufreq driver and Energy Model framework to
set the performance domains scale: milli-Watts or abstract scale.
Suggested-by: Morten Rasmussen <morten.rasmussen@arm.com>
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Few commands provide the list of description partially and require
to be called consecutively until all the descriptors are fetched
completely. In such cases, we don't release the buffers and reuse
them for consecutive transmits.
However, currently we don't reset the Rx size which will be set as
per the response for the last transmit. This may result in incorrect
response size being interpretted as the firmware may repond with size
greater than the one set but we read only upto the size set by previous
response.
Let us reset the receive buffer size to max possible in such cases as
we don't know the exact size of the response.
Link: https://lore.kernel.org/r/20201012141746.32575-1-sudeep.holla@arm.com
Fixes: b6f20ff8bd ("firmware: arm_scmi: add common infrastructure and support for base protocol")
Reported-by: Etienne Carriere <etienne.carriere@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
In preparation to enable building SCMI as a single module, let us move
the SCMI protocol registration call into the driver. This enables us
to also add unregistration of the SCMI protocols.
The main reason for this is to keep it simple instead of maintaining
it as separate modules and dealing with all possible initcall races
and deferred probe handling. We can move it as separate modules if
needed in future.
Link: https://lore.kernel.org/r/20200907195046.56615-4-sudeep.holla@arm.com
Tested-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Event reports are used to convey information describing events to the
registered user-callbacks: they are necessarily derived from the underlying
raw SCMI events' messages but they are not meant to expose or directly
mirror any of those messages data layout, which belong to the protocol
layer.
Using fixed size types for report fields, mirroring messages structure,
is at odd with this: get rid of them using more generic, equivalent,
typing.
Substitute scmi_event_header fixed size fields with generic types too and
shuffle around fields definitions to minimize implicit padding while
adapting involved functions.
Link: https://lore.kernel.org/r/20200710133919.39792-3-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Add a new fast_switch_possible interface to the existing perf_ops to
export the information of whether or not fast_switch is possible for a
given device.
This can be used by the cpufreq driver and framework to choose proper
mechanism for frequency change.
Link: https://lore.kernel.org/r/20200617094332.8391-1-nicola.mazzucato@arm.com
Suggested-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Nicola Mazzucato <nicola.mazzucato@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
