Commit Graph

19 Commits

Author SHA1 Message Date
Sudeep Holla
9dc34d635c firmware: arm_scmi: Check if platform has released shmem before using
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>
2019-08-12 12:22:59 +01:00
Sudeep Holla
5b65af8f60 firmware: arm_scmi: Use the term 'message' instead of 'command'
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>
2019-08-12 12:22:58 +01:00
Sudeep Holla
c29a628976 firmware: arm_scmi: Fix few trivial typos in comments
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>
2019-08-12 12:22:58 +01:00
Sudeep Holla
37bbffcb19 firmware: arm_scmi: Remove extra check for invalid length message responses
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>
2019-08-12 12:22:58 +01:00
Aditya Pakki
d9350f21e5 firmware: arm_scmi: replace of_match_device->data with of_device_get_match_data()
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>
2019-04-12 18:11:18 +01:00
Steven Price
fa7fe29a64 firmware: arm_scmi: fix of_node leak in scmi_mailbox_check
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>
2019-04-12 18:11:18 +01:00
Linus Torvalds
32bcbf8b6d ARM: SoC driver updates
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
  ...
2018-06-11 18:15:22 -07:00
Sudeep Holla
632de8f542 firmware: arm_scmi: simplify exit path by returning on error
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>
2018-05-10 10:52:00 +01:00
Sudeep Holla
8f3397ccb6 firmware: arm_scmi: remove unnecessary bitmap_zero
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>
2018-05-10 10:51:58 +01:00
Sudeep Holla
14e297b3b8 firmware: arm_scmi: rename scmi_xfer_{init,get,put}
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>
2018-05-10 10:51:57 +01:00
Sudeep Holla
1baf47c2e5 firmware: arm_scmi: fix kernel-docs documentation
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>
2018-05-09 17:52:06 +01:00
Sudeep Holla
354b2e36d7 firmware: arm_scmi: improve code readability using bitfield accessor macros
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>
2018-05-09 17:52:06 +01:00
Dan Carpenter
31c6085562 firmware: arm_scmi: Use after free in scmi_create_protocol_device()
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>
2018-05-08 18:03:47 +01:00
Sudeep Holla
907b6d1491 firmware: arm_scmi: add per-protocol channels support using idr objects
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>
2018-02-28 16:37:57 +00:00
Sudeep Holla
fbc4d81ad2 firmware: arm_scmi: refactor in preparation to support per-protocol channels
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>
2018-02-28 16:37:57 +00:00
Sudeep Holla
d4c3751a8d firmware: arm_scmi: add support for polling based SCMI transfers
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>
2018-02-28 16:37:57 +00:00
Sudeep Holla
bc40081d98 firmware: arm_scmi: probe and initialise all the supported protocols
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>
2018-02-28 16:37:57 +00:00
Sudeep Holla
b6f20ff8bd firmware: arm_scmi: add common infrastructure and support for base protocol
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>
2018-02-28 16:37:57 +00:00
Sudeep Holla
aa4f886f38 firmware: arm_scmi: add basic driver infrastructure for SCMI
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>
2018-02-28 16:37:57 +00:00