The scmi bus now supports adding multiple devices per protocol,
and since scmi_protocol_init is called for each scmi device created,
we must avoid allocating protocol private data and initialising the
protocol itself if it is already initialised.
In order to achieve the same, we can simple replace the idr pointer
from protocol initialisation function to a dummy function.
Suggested-by: Cristian Marussi <cristian.marussi@arm.com>
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
In order to avoid querying the individual protocol versions multiple
time with more that one device created for each protocol, we can simple
store the copy in the protocol specific private data and use them whenever
required.
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The scmi bus now has support to match the driver with devices not only
based on their protocol id but also based on their device name if one is
available. This was added to cater the need to support multiple devices
and drivers for the same protocol.
Let us add the name "genpd" to scmi_device_id table in the driver so
that in matches only with device with the same name and protocol id
SCMI_PROTOCOL_POWER.
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Platform drivers now have the option to have the platform core create
and remove any needed sysfs attribute files. Using the same, let's add
the scmi firmware and protocol version attributes as well as vendor and
sub-vendor identifiers to sysfs.
It helps to identify the firmware details from the sysfs entries similar
to ARM SCPI implementation.
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Now that scmi bus provides option to create named scmi device, let us
create the default devices with names. This will help to add names for
matching to respective drivers and eventually to add multiple devices
and drivers per protocol.
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Now that the scmi bus supports adding multiple devices per protocol,
and since scmi_create_protocol_device calls scmi_mbox_chan_setup,
we must avoid allocating and initialising the mbox channel if it is
already initialised.
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Currently only one scmi device is created for each protocol enumerated.
However, there is requirement to make use of some procotols by multiple
kernel subsystems/frameworks. One such example is SCMI PERFORMANCE
protocol which can be used by both cpufreq and devfreq drivers.
Similarly, SENSOR protocol may be used by hwmon and iio subsystems,
and POWER protocol may be used by genpd and regulator drivers.
In order to achieve that, let us extend the scmi bus to match based
not only protocol id but also the scmi device name if one is available.
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
If device_register() fails, both put_device() and kfree() are called,
ending with a double free of the scmi_dev.
Calling kfree() is needed only when a failure happens between the
allocation of the scmi_dev and its registration, so move it to there
and remove it from the error flow.
Fixes: 46edb8d132 ("firmware: arm_scmi: provide the mandatory device release callback")
Signed-off-by: Wen Yang <wenyang@linux.alibaba.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The logic to ring the scmi performance fastchannel ignores the
value read from the doorbell register in case of !CONFIG_64BIT.
This bug also shows up as warning with '-Wunused-but-set-variable' gcc
flag:
drivers/firmware/arm_scmi/perf.c: In function scmi_perf_fc_ring_db:
drivers/firmware/arm_scmi/perf.c:323:7: warning: variable val set but
not used [-Wunused-but-set-variable]
Fix the same by aligning the logic with CONFIG_64BIT as used in the
macro SCMI_PERF_FC_RING_DB().
Fixes: 823839571d ("firmware: arm_scmi: Make use SCMI v2.0 fastchannel for performance protocol")
Reported-by: Hulk Robot <hulkci@huawei.com>
Reported-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
SCMIv2.0 adds a new Reset Management Protocol to manage various reset
states a given device or domain can enter. Device(s) that can be
collectively reset through a common reset signal constitute a reset
domain for the firmware.
A reset domain can be reset autonomously or explicitly through assertion
and de-assertion of the signal. When autonomous reset is chosen, the
firmware is responsible for taking the necessary steps to reset the
domain and to subsequently bring it out of reset. When explicit reset is
chosen, the caller has to specifically assert and then de-assert the
reset signal by issuing two separate RESET commands.
Add the basic SCMI reset infrastructure that can be used by Linux
reset controller driver.
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
SCMI v2.0 adds support for "FastChannel" which do not use a message
header as they are specialized for a single message.
Only PERFORMANCE_LIMITS_{SET,GET} and PERFORMANCE_LEVEL_{SET,GET}
commands are supported over fastchannels. As they are optional, they
need to be discovered by PERFORMANCE_DESCRIBE_FASTCHANNEL command.
Further {LIMIT,LEVEL}_SET commands can have optional doorbell support.
Add support for making use of these fastchannels.
Cc: Ionela Voinescu <Ionela.Voinescu@arm.com>
Cc: Chris Redpath <Chris.Redpath@arm.com>
Cc: Quentin Perret <Quentin.Perret@arm.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
SCMI v2.0 adds support for "FastChannel", a lightweight unidirectional
channel that is dedicated to a single SCMI message type for controlling
a specific platform resource. They do not use a message header as they
are specialized for a single message.
Only PERFORMANCE_LIMITS_{SET,GET} and PERFORMANCE_LEVEL_{SET,GET}
commands are supported over fastchannels. As they are optional, they
need to be discovered by PERFORMANCE_DESCRIBE_FASTCHANNEL command.
Further {LIMIT,LEVEL}_SET commands can have optional doorbell support.
Add support for discovery of these fastchannels.
Cc: Ionela Voinescu <Ionela.Voinescu@arm.com>
Cc: Chris Redpath <Chris.Redpath@arm.com>
Cc: Quentin Perret <Quentin.Perret@arm.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Instead of type-casting the {tx,rx}.buf all over the place while
accessing them to read/write __le{32,64} from/to the firmware, let's
use the existing {get,put}_unaligned_le{32,64} accessors to hide all
the type cast ugliness.
Suggested-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
CLOCK_PROTOCOL_ATTRIBUTES provides attributes to indicate the maximum
number of pending asynchronous clock rate changes supported by the
platform. If it's non-zero, then we should be able to use asynchronous
clock rate set for any clocks until the maximum limit is reached.
Tracking the current count of pending asynchronous clock set rate
requests, we can decide if the incoming/new request for clock set rate
can be handled asynchronously or not until the maximum limit is
reached.
Cc: linux-clk@vger.kernel.org
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
CLOCK_PROTOCOL_ATTRIBUTES provides attributes to indicate the maximum
number of pending asynchronous clock rate changes supported by the
platform. If it's non-zero, then we should be able to use asynchronous
clock rate set for any clocks until the maximum limit is reached.
In order to add that support, let's drop the config flag passed to
clk_ops->rate_set and handle the asynchronous requests dynamically.
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: linux-clk@vger.kernel.org
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
SENSOR_DESCRIPTION_GET provides attributes to indicate if the sensor
supports asynchronous read. We can read that flag and use asynchronous
reads for any sensors with that attribute set.
Let's use the new scmi_do_xfer_with_response to support asynchronous
sensor reads.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
SENSOR_DESCRIPTION_GET provides attributes to indicate if the sensor
supports asynchronous read. Ideally we should be able to read that flag
and use asynchronous reads for any sensors with that attribute set.
In order to add that support, let's drop the async flag passed to
sensor_ops->reading_get and dynamically switch between sync and async
flags based on the attributes as provided by the firmware.
Cc: linux-hwmon@vger.kernel.org
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Messages that are sent to platform, also known as commands and can be:
1. Synchronous commands that block the channel until the requested work
has been completed. The platform responds to these commands over the
same channel and hence can't be used to send another command until the
previous command has completed.
2. Asynchronous commands on the other hand, the platform schedules the
requested work to complete later in time and returns almost immediately
freeing the channel for new commands. The response indicates the success
or failure in the ability to schedule the requested work. When the work
has completed, the platform sends an additional delayed response message.
Using the same transmit buffer used for sending the asynchronous command
even for the delayed response corresponding to it simplifies handling of
the delayed response. It's the caller of asynchronous command that is
responsible for allocating the completion flag that scmi driver can
complete to indicate the arrival of delayed response.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
In order to identify the message type when a response arrives, we need
a mechanism to unpack the message header similar to packing. Let's
add one.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Currently we pre-allocate transmit buffers only and use the first free
slot in that pre-allocated buffer for transmitting any new message that
are generally originated from OS to the platform firmware.
Notifications or the delayed responses on the other hand are originated
from the platform firmware and consumes by the OS. It's better to have
separate and dedicated pre-allocated buffers to handle the notifications.
We can still use the transmit buffers for the delayed responses.
In addition, let's prepare existing scmi_xfer_{get,put} for acquiring
and releasing a slot to identify the right(tx/rx) buffers.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
With scmi_mbox_chan_setup enabled to identify and setup both Tx and Rx,
let's consolidate setting up of both the channels under the function
scmi_mbox_txrx_setup.
Since some platforms may opt not to support notifications or delayed
response, they may not need support for Rx. Hence Rx is optional and
failure of setting one up is not considered fatal.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The transmit(Tx) channels are specified as the first entry and the
receive(Rx) channels are the second entry as per the device tree
bindings. Since we currently just support Tx, index 0 is hardcoded at
all required callsites.
In order to prepare for adding Rx support, let's remove those hardcoded
index and add boolean parameter to identify Tx/Rx channels when setting
them up.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Re-shuffling few functions to keep definitions and their usages close.
This is also needed to avoid too many unnecessary forward declarations
while adding new features(delayed response and notifications).
Keeping this separate to avoid mixing up of these trivial change that
doesn't affect functionality into the ones that does.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Sometimes platfom may take too long to respond to the command and OS
might timeout before platform transfer the ownership of the shared
memory region to the OS with the response.
Since the mailbox channel associated with the channel is freed and new
commands are dispatch on the same channel, OS needs to wait until it
gets back the ownership. If not, either OS may end up overwriting the
platform response for the last command(which is fine as OS timed out
that command) or platform might overwrite the payload for the next
command with the response for the old.
The latter is problematic as platform may end up interpretting the
response as the payload. In order to avoid such race, let's wait until
the OS gets back the ownership before we prepare the shared memory with
the payload for the next command.
Reported-by: Jim Quinlan <james.quinlan@broadcom.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
In preparation to adding support for other two types of messages that
SCMI specification mentions, let's replace the term 'command' with the
correct term 'message'.
As per the specification the messages are of 3 types:
commands(synchronous or asynchronous), delayed responses and notifications.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
While adding new comments found couple of typos that are better fixed.
s/informfation/information/
s/statues/status/
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
scmi_xfer_get_init ensures both transmit and receive buffer lengths are
within the maximum limits. If receive buffer length is not supplied by
the caller, it's set to the maximum limit value. Receive buffer length
is never modified after that. So there's no need for the extra check
when receive transmit completion for a command essage.
Further, if the response header length is greater than the prescribed
receive buffer length, the response buffer is truncated to the latter.
Reported-by: Jim Quinlan <james.quinlan@broadcom.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Looks like more code developed during the draft versions of the
specification slipped through and they don't match the final
released version. This seem to have happened only with sensor
protocol.
Renaming few command and function names here to match exactly with
the released version of SCMI specification for ease of maintenance.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Various driver updates for platforms and a couple of the small driver
subsystems we merge through our tree:
- A driver for SCU (system control) on NXP i.MX8QXP
- Qualcomm Always-on Subsystem messaging driver (AOSS QMP)
- Qualcomm PM support for MSM8998
- Support for a newer version of DRAM PHY driver for Broadcom (DPFE)
- Reset controller support for Bitmain BM1880
- TI SCI (System Control Interface) support for CPU control on AM654
processors
- More TI sysc refactoring and rework
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Merge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull ARM SoC-related driver updates from Olof Johansson:
"Various driver updates for platforms and a couple of the small driver
subsystems we merge through our tree:
- A driver for SCU (system control) on NXP i.MX8QXP
- Qualcomm Always-on Subsystem messaging driver (AOSS QMP)
- Qualcomm PM support for MSM8998
- Support for a newer version of DRAM PHY driver for Broadcom (DPFE)
- Reset controller support for Bitmain BM1880
- TI SCI (System Control Interface) support for CPU control on AM654
processors
- More TI sysc refactoring and rework"
* tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (84 commits)
reset: remove redundant null check on pointer dev
soc: rockchip: work around clang warning
dt-bindings: reset: imx7: Fix the spelling of 'indices'
soc: imx: Add i.MX8MN SoC driver support
soc: aspeed: lpc-ctrl: Fix probe error handling
soc: qcom: geni: Add support for ACPI
firmware: ti_sci: Fix gcc unused-but-set-variable warning
firmware: ti_sci: Use the correct style for SPDX License Identifier
soc: imx8: Use existing of_root directly
soc: imx8: Fix potential kernel dump in error path
firmware/psci: psci_checker: Park kthreads before stopping them
memory: move jedec_ddr.h from include/memory to drivers/memory/
memory: move jedec_ddr_data.c from lib/ to drivers/memory/
MAINTAINERS: Remove myself as qcom maintainer
soc: aspeed: lpc-ctrl: make parameter optional
soc: qcom: apr: Don't use reg for domain id
soc: qcom: fix QCOM_AOSS_QMP dependency and build errors
memory: tegra: Fix -Wunused-const-variable
firmware: tegra: Early resume BPMP
soc/tegra: Select pinctrl for Tegra194
...
This patch corrects the SPDX License Identifier style
in header file related to Firmware Drivers for ARM SCMI
Message Protocol.
For C header files Documentation/process/license-rules.rst
mandates C-like comments (opposed to C source files where
C++ style should be used)
Changes made by using a script provided by Joe Perches here:
https://lkml.org/lkml/2019/2/7/46
Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1. Correction to ARM document ID referred in SCMI protocol binding
2. Fix to correct bitfield definitions for SENSOR_DESC attributes which
otherwise will calculate sensor values on wrong scale
3. Adds the missing rate_discrete flag setting so that discrete clocks
are handled correctly. Without this fix it assumes continuous range
which is incorrect
4. Adds support to read and scale the sensor values based on the factor
read from the firmware
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Merge tag 'scmi-updates-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux into arm/drivers
ARM SCMI updates/fixes for v5.3
1. Correction to ARM document ID referred in SCMI protocol binding
2. Fix to correct bitfield definitions for SENSOR_DESC attributes which
otherwise will calculate sensor values on wrong scale
3. Adds the missing rate_discrete flag setting so that discrete clocks
are handled correctly. Without this fix it assumes continuous range
which is incorrect
4. Adds support to read and scale the sensor values based on the factor
read from the firmware
* tag 'scmi-updates-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux:
hwmon: scmi: Scale values to target desired HWMON units
firmware: arm_scmi: fetch and store sensor scale
firmware: arm_scmi: update rate_discrete in clock_describe_rates_get
firmware: arm_scmi: fix bitfield definitions for SENSOR_DESC attributes
dt-bindings: arm: fix the document ID for SCMI protocol documentation
Signed-off-by: Olof Johansson <olof@lixom.net>
In preparation for dealing with scales within the SCMI HWMON driver,
fetch and store the sensor unit scale into the scmi_sensor_info
structure. In order to simplify computations for upper layer, take care
of sign extending the scale to a full 8-bit signed value.
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
[sudeep.holla: update bitfield values as per specification]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The boolean rate_discrete needs to be assigned to clk->rate_discrete,
so that clock driver can distinguish between the continuous range and
discrete rates. It uses this in scmi_clk_round_rate could get the
rounded value if it's a continuous range.
Fixes: 5f6c6430e9 ("firmware: arm_scmi: add initial support for clock protocol")
Signed-off-by: Peng Fan <peng.fan@nxp.com>
[sudeep.holla: updated commit message]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
As per the SCMI specification the bitfields for SENSOR_DESC attributes
are as follows:
attributes_low [7:0] Number of trip points supported
attributes_high [15:11] The power-of-10 multiplier in 2's-complement
format that is applied to the sensor units
Looks like the code developed during the draft versions of the
specification slipped through and are wrong with respect to final
released version. Fix them by adjusting the bitfields appropriately.
Fixes: 5179c523c1 ("firmware: arm_scmi: add initial support for sensor protocol")
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
of_match_device can return NULL if no matching device is found though
it's highly unlikely to happen in scmi_probe as it's called only if
a valid match is found.
However we can use of_device_get_match_data() instead of
of_match_device()->data to handle NULL pointer checks and return -EINVAL
in such a scenario.
Reviewed-by: Steven Price <steven.price@arm.com>
Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
of_parse_phandle_with_args() requires the caller to call of_node_put() on
the returned args->np pointer. Otherwise the reference count will remain
incremented.
However, in this case, since we don't actually use the returned pointer,
we can simply pass in NULL.
Fixes: aa4f886f38 ("firmware: arm_scmi: add basic driver infrastructure for SCMI")
Signed-off-by: Steven Price <steven.price@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The device/driver model clearly mandates that bus driver that discover
and allocate the device must set the release callback. This callback
will be used to free the device after all references have gone away.
scmi bus driver is missing the obvious callback which will result in
the following warning if the device is unregistered:
Device 'scmi_dev.1' does not have a release() function, it is broken and
must be fixed. See Documentation/kobject.txt.
WARNING at drivers/base/core.c:922 device_release+0x8c/0xa0
Hardware name: ARM LTD Juno Development Platform BIOS EDK II Jan 21 2019
Workqueue: events deferred_probe_work_func
pstate: 60000005 (nZCv daif -PAN -UAO)
pc : device_release+0x8c/0xa0
lr : device_release+0x8c/0xa0
Call trace:
device_release+0x8c/0xa0
kobject_put+0x8c/0x208
device_unregister+0x30/0x78
scmi_device_destroy+0x28/0x50
scmi_probe+0x354/0x5b0
platform_drv_probe+0x58/0xa8
really_probe+0x2c4/0x3e8
driver_probe_device+0x12c/0x148
__device_attach_driver+0xac/0x150
bus_for_each_drv+0x78/0xd8
__device_attach+0xe0/0x168
device_initial_probe+0x24/0x30
bus_probe_device+0xa0/0xa8
deferred_probe_work_func+0x8c/0xe0
process_one_work+0x1f0/0x478
worker_thread+0x22c/0x450
kthread+0x134/0x138
ret_from_fork+0x10/0x1c
---[ end trace 420bdb7f6af50937 ]---
Fix the issue by providing scmi_device_release callback. We have
everything required for device release already in scmi_device_destroy,
so we just need to move freeing of the device to scmi_device_release.
Fixes: 933c504424 ("firmware: arm_scmi: add scmi protocol bus to enumerate protocol devices")
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Cc: stable@vger.kernel.org # 4.17+
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The SCMI protocol can be used to get power estimates from firmware
corresponding to each performance state of a device. Although these power
costs are already managed by the SCMI firmware driver, they are not
exposed to any external subsystem yet.
Fix this by adding a new get_power() interface to the exisiting perf_ops
defined for the SCMI protocol.
Signed-off-by: Quentin Perret <quentin.perret@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Replace all the memcpy() for copying name strings from the firmware with
strlcpy() to make sure we are bounded by the source buffer size and we
also always have NULL-terminated strings.
This is needed to avoid out of bounds accesses if the firmware returns
a non-terminated string.
Reported-by: Olof Johansson <olof@lixom.net>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Firmware can provide zero as values for sustained performance level and
corresponding sustained frequency in kHz in order to hide the actual
frequencies and provide only abstract values. It may endup with divide
by zero scenario resulting in kernel panic.
Let's set the multiplication factor to one if either one or both of them
(sustained_perf_level and sustained_freq) are set to zero.
Fixes: a9e3fbfaa0 ("firmware: arm_scmi: add initial support for performance protocol")
Reported-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
The "pi->dom_info" buffer is allocated in init() and it can't be NULL
here. These tests are sort of weird as well because if "pi->dom_info"
was NULL but "domain" was non-zero then it would lead to an Oops.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
This branch contains platform-related driver updates for ARM and ARM64.
Highlights:
- ARM SCMI (System Control & Management Interface) driver cleanups
- Hisilicon support for LPC bus w/ ACPI
- Reset driver updates for several platforms: Uniphier,
- Rockchip power domain bindings and hardware descriptions for several SoCs.
- Tegra memory controller reset improvements
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Merge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC driver updates from Olof Johansson:
"This contains platform-related driver updates for ARM and ARM64.
Highlights:
- ARM SCMI (System Control & Management Interface) driver cleanups
- Hisilicon support for LPC bus w/ ACPI
- Reset driver updates for several platforms: Uniphier,
- Rockchip power domain bindings and hardware descriptions for
several SoCs.
- Tegra memory controller reset improvements"
* tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (59 commits)
ARM: tegra: fix compile-testing PCI host driver
soc: rockchip: power-domain: add power domain support for px30
dt-bindings: power: add binding for px30 power domains
dt-bindings: power: add PX30 SoCs header for power-domain
soc: rockchip: power-domain: add power domain support for rk3228
dt-bindings: power: add binding for rk3228 power domains
dt-bindings: power: add RK3228 SoCs header for power-domain
soc: rockchip: power-domain: add power domain support for rk3128
dt-bindings: power: add binding for rk3128 power domains
dt-bindings: power: add RK3128 SoCs header for power-domain
soc: rockchip: power-domain: add power domain support for rk3036
dt-bindings: power: add binding for rk3036 power domains
dt-bindings: power: add RK3036 SoCs header for power-domain
dt-bindings: memory: tegra: Remove Tegra114 SATA and AFI reset definitions
memory: tegra: Remove Tegra114 SATA and AFI reset definitions
memory: tegra: Register SMMU after MC driver became ready
soc: mediatek: remove unneeded semicolon
soc: mediatek: add a fixed wait for SRAM stable
soc: mediatek: introduce a CAPS flag for scp_domain_data
soc: mediatek: reuse regmap_read_poll_timeout helpers
...
This contains all of the trivial review comments that were not
addressed as the series was already queued up for v4.17 and were not
critical to go as fixes.
They generally just improve code readability, fix kernel-docs, remove
unused/unnecessary code, follow standard function naming and simplifies
certain exit paths.
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Merge tag 'scmi-updates-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux into next/drivers
SCMI cleanups for v4.18
This contains all of the trivial review comments that were not
addressed as the series was already queued up for v4.17 and were not
critical to go as fixes.
They generally just improve code readability, fix kernel-docs, remove
unused/unnecessary code, follow standard function naming and simplifies
certain exit paths.
* tag 'scmi-updates-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux:
firmware: arm_scmi: simplify exit path by returning on error
firmware: arm_scmi: improve exit paths and code readability
firmware: arm_scmi: remove unnecessary bitmap_zero
firmware: arm_scmi: drop unused `con_priv` structure member
firmware: arm_scmi: rename scmi_xfer_{init,get,put}
firmware: arm_scmi: rename get_transition_latency and add_opps_to_device
firmware: arm_scmi: fix kernel-docs documentation
firmware: arm_scmi: improve code readability using bitfield accessor macros
Signed-off-by: Olof Johansson <olof@lixom.net>
A single patch to ensure that the scmi device is not used for setting up
scmi handle after it's freed(fixes use after free).
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Merge tag 'scmi-fixes-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux into fixes
SCMI fix for v4.17
A single patch to ensure that the scmi device is not used for setting up
scmi handle after it's freed(fixes use after free).
* tag 'scmi-fixes-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux:
firmware: arm_scmi: Use after free in scmi_create_protocol_device()
Signed-off-by: Olof Johansson <olof@lixom.net>
Yet another nasty indentation left out during code restructuring. It's
must simpler to return on error instead of having unnecessary indentation.
Suggested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The existing code intends the good path to reduce the code which is so
uncommon. It's obvious to have more readable code with a goto used for
the error path. This patch adds more appropriate error paths and makes
code more readable. It also moves a error logging outside the scope of
locking.
Suggested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
kcalloc zeros the memory and it's totally unnecessary to zero the bitmap
again using bitmap_zero. This patch just drops the unnecessary use of
the bitmap_zero in the context.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Initially con_priv was supposedly used for transport specific data when
the SCMI driver had an abstraction to communicate with different mailbox
controllers. But after some discussions, the idea was dropped but this
variable slipped through the cracks.
This patch gets rid of this unused variable.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Just after the initial patches were queued, Jonathan Cameron mentioned
that scmi_one_xfer_{get_put} were not very clear and suggested to use
scmi_xfer_{alloc,free}. While I agree to some extent, the reason not to
have alloc/free as these are preallocated buffers and these functions
just returns a reference to free slot in that preallocated array.
However it was agreed to drop "_one" as it's implicit that we are always
dealing with one slot anyways.
This patch updates the name accordingly dropping "_one" in both {get,put}
functions. Also scmi_one_xfer_init is renamed as scmi_xfer_get_init to
reflect the fact that it gets the free slots and then initialise it.
Reported-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Most of the scmi code follows the suggestion from Greg KH on a totally
different thread[0] to have the subsystem name first, followed by the
noun and finally the verb with couple of these exceptions.
This patch fixes them so that all the functions names are aligned to
that practice.
[0] https://www.spinics.net/lists/arm-kernel/msg583673.html
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
There are few missing descriptions for function parameters and structure
members along with certain instances where excessive function parameters
or structure members are described.
This patch fixes all of those warnings.
Reported-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
By using FIELD_{FIT,GET,PREP} and GENMASK macro accessors we can avoid
some clumpsy custom shifting and masking macros and also improve the
code better readability.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
We need to return here instead of setting up the freed sdev device as a
transport.
Fixes: 907b6d1491 ("firmware: arm_scmi: add per-protocol channels support using idr objects")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The null check on clk->name is redundant since name is a char array
and can never be null, so the check is always true. Remove it.
Detected by CoverityScan, CID#1466117 ("Array compared against 0")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
gcc-5.3 and earlier warns that rate_discrete maybe-uninitialized
../drivers/firmware/arm_scmi/clock.c:185:5: warning: 'rate_discrete'
may be used uninitialized in this function [-Wmaybe-uninitialized]
if (rate_discrete)
^
../drivers/firmware/arm_scmi/clock.c:128:7: note:
'rate_discrete' was declared here
bool rate_discrete;
^
This patch fixing the warning by initialising rate_discrete and also using
goto label for the error path.
Fixes: 5f6c6430e9 ("firmware: arm_scmi: add initial support for clock protocol")
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
[sudeep.holla: added one line description to the commit message]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
This patch hooks up the support for device power domain provided by
SCMI using the Linux generic power domain infrastructure.
Cc: Kevin Hilman <khilman@baylibre.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
In order to maintain the channel information per protocol, we need
some sort of list or hashtable to hold all this information. IDR
provides sparse array mapping of small integer ID numbers onto arbitrary
pointers. In this case the arbitrary pointers can be pointers to the
channel information.
This patch adds support for per-protocol channels using those idr
objects.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
In order to support per-protocol channels if available, we need to
factor out all the mailbox channel information(Tx/Rx payload and
channel handle) out of the main SCMI instance information structure.
This patch refactors the existing channel information into a separate
chan_info structure.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
In order to implement fast CPU DVFS switching, we need to perform all
DVFS operations atomically. Since SCMI transfer already provide option
to choose between pooling vs interrupt driven(default), we can opt for
polling based transfers for set,get performance domain operations.
This patch adds option to choose between polling vs interrupt driven
SCMI transfers for set,get performance level operations.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
It would be useful to have options to perform some SCMI transfers
atomically by polling for the completion flag instead of interrupt
driven. The SCMI specification has option to disable the interrupt and
poll for the completion flag in the shared memory.
This patch adds support for polling based SCMI transfers using that
option. This might be used for uninterrupted/atomic DVFS operations
from the scheduler context.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Now that we have basic support for all the protocols in the
specification, let's probe them individually and initialise them.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The sensor protocol provides functions to manage platform sensors, and
provides the commands to describe the protocol version and the various
attribute flags. It also provides commands to discover various sensors
implemented and managed by the platform, read any sensor synchronously
or asynchronously as allowed by the platform, program sensor attributes
and/or configurations, if applicable.
This patch adds support for most of the above features.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The power protocol is intended for management of power states of various
power domains. The power domain management protocol provides commands to
describe the protocol version, discover the implementation specific
attributes, set and get the power state of a domain.
This patch adds support for the above mention features of the protocol.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
--
drivers/firmware/arm_scmi/Makefile | 2 +-
drivers/firmware/arm_scmi/power.c | 242 +++++++++++++++++++++++++++++++++++++
include/linux/scmi_protocol.h | 28 +++++
3 files changed, 271 insertions(+), 1 deletion(-)
create mode 100644 drivers/firmware/arm_scmi/power.c
The clock protocol is intended for management of clocks. It is used to
enable or disable clocks, and to set and get the clock rates. This
protocol provides commands to describe the protocol version, discover
various implementation specific attributes, describe a clock, enable
and disable a clock and get/set the rate of the clock synchronously or
asynchronously.
This patch adds initial support for the clock protocol.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The performance protocol is intended for the performance management of
group(s) of device(s) that run in the same performance domain. It
includes even the CPUs. A performance domain is defined by a set of
devices that always have to run at the same performance level.
For example, a set of CPUs that share a voltage domain, and have a
common frequency control, is said to be in the same performance domain.
The commands in this protocol provide functionality to describe the
protocol version, describe various attribute flags, set and get the
performance level of a domain. It also supports discovery of the list
of performance levels supported by a performance domain, and the
properties of each performance level.
This patch adds basic support for the performance protocol.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The SCMI specification encompasses various protocols. However, not every
protocol has to be present on a given platform/implementation as not
every protocol is relevant for it.
Furthermore, the platform chooses which protocols it exposes to a given
agent. The only protocol that must be implemented is the base protocol.
The base protocol is used by an agent to discover which protocols are
available to it.
In order to enumerate the discovered implemented protocols, this patch
adds support for a separate scmi protocol bus. It also adds mechanism to
register support for different protocols.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The base protocol describes the properties of the implementation and
provide generic error management. The base protocol provides commands
to describe protocol version, discover implementation specific
attributes and vendor/sub-vendor identification, list of protocols
implemented and the various agents are in the system including OSPM
and the platform. It also supports registering for notifications of
platform errors.
This protocol is mandatory. This patch adds support for the same along
with some basic infrastructure to add support for other protocols.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The SCMI is intended to allow OSPM to manage various functions that are
provided by the hardware platform it is running on, including power and
performance functions. SCMI provides two levels of abstraction, protocols
and transports. Protocols define individual groups of system control and
management messages. A protocol specification describes the messages
that it supports. Transports describe the method by which protocol
messages are communicated between agents and the platform.
This patch adds basic infrastructure to manage the message allocation,
initialisation, packing/unpacking and shared memory management.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
