Commit Graph

140 Commits

Author SHA1 Message Date
Cristian Marussi
85b637feee firmware: arm_scmi: Fix device node validation for mailbox transport
commit 2ab4f4018cb6b8010ca5002c3bdc37783b5d28c2 upstream.

When mailboxes are used as a transport it is possible to setup the SCMI
transport layer, depending on the underlying channels configuration, to use
one or two mailboxes, associated, respectively, to one or two, distinct,
shared memory areas: any other combination should be treated as invalid.

Add more strict checking of SCMI mailbox transport device node descriptors.

Fixes: 5c8a47a5a9 ("firmware: arm_scmi: Make scmi core independent of the transport type")
Cc: <stable@vger.kernel.org> # 4.19
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20230307162324.891866-1-cristian.marussi@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-05 11:23:42 +02:00
Cristian Marussi
6813d8ba7d firmware: arm_scmi: Harden shared memory access in fetch_notification
[ Upstream commit 9bae076cd4e3e3c3dc185cae829d80b2dddec86e ]

A misbheaving SCMI platform firmware could reply with out-of-spec
notifications, shorter than the mimimum size comprising a header.

Fixes: d5141f37c4 ("firmware: arm_scmi: Add notifications support in transport layer")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20221222183823.518856-4-cristian.marussi@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-01 08:23:10 +01:00
Cristian Marussi
e85df1db28 firmware: arm_scmi: Harden shared memory access in fetch_response
[ Upstream commit ad78b81a1077f7d956952cd8bdfe1e61504e3eb8 ]

A misbheaving SCMI platform firmware could reply with out-of-spec messages,
shorter than the mimimum size comprising a header and a status field.

Harden shmem_fetch_response to properly truncate such a bad messages.

Fixes: 5c8a47a5a9 ("firmware: arm_scmi: Make scmi core independent of the transport type")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20221222183823.518856-3-cristian.marussi@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-01 08:23:09 +01:00
Cristian Marussi
b743ecf29c firmware: arm_scmi: Make Rx chan_setup fail on memory errors
[ Upstream commit be9ba1f7f9e0b565b19f4294f5871da9d654bc6d ]

SCMI Rx channels are optional and they can fail to be setup when not
present but anyway channels setup routines must bail-out on memory errors.

Make channels setup, and related probing, fail when memory errors are
reported on Rx channels.

Fixes: 5c8a47a5a9 ("firmware: arm_scmi: Make scmi core independent of the transport type")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20221028140833.280091-4-cristian.marussi@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 18:14:23 +01:00
Cristian Marussi
29e8e9bfc2 firmware: arm_scmi: Suppress the driver's bind attributes
[ Upstream commit fd96fbc8fad35d6b1872c90df8a2f5d721f14d91 ]

Suppress the capability to unbind the core SCMI driver since all the
SCMI stack protocol drivers depend on it.

Fixes: aa4f886f38 ("firmware: arm_scmi: add basic driver infrastructure for SCMI")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20221028140833.280091-2-cristian.marussi@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 18:14:23 +01:00
Cristian Marussi
64e240934c firmware: arm_scmi: Add SCMI PM driver remove routine
[ Upstream commit dea796fcab0a219830831c070b8dc367d7e0f708 ]

Currently, when removing the SCMI PM driver not all the resources
registered with genpd subsystem are properly de-registered.

As a side effect of this after a driver unload/load cycle you get a
splat with a few warnings like this:

 | debugfs: Directory 'BIG_CPU0' with parent 'pm_genpd' already present!
 | debugfs: Directory 'BIG_CPU1' with parent 'pm_genpd' already present!
 | debugfs: Directory 'LITTLE_CPU0' with parent 'pm_genpd' already present!
 | debugfs: Directory 'LITTLE_CPU1' with parent 'pm_genpd' already present!
 | debugfs: Directory 'LITTLE_CPU2' with parent 'pm_genpd' already present!
 | debugfs: Directory 'LITTLE_CPU3' with parent 'pm_genpd' already present!
 | debugfs: Directory 'BIG_SSTOP' with parent 'pm_genpd' already present!
 | debugfs: Directory 'LITTLE_SSTOP' with parent 'pm_genpd' already present!
 | debugfs: Directory 'DBGSYS' with parent 'pm_genpd' already present!
 | debugfs: Directory 'GPUTOP' with parent 'pm_genpd' already present!

Add a proper scmi_pm_domain_remove callback to the driver in order to
take care of all the needed cleanups not handled by devres framework.

Link: https://lore.kernel.org/r/20220817172731.1185305-7-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-15 07:55:51 +02:00
Cristian Marussi
1052f22e12 firmware: arm_scmi: Fix list protocols enumeration in the base protocol
[ Upstream commit 8009120e0354a67068e920eb10dce532391361d0 ]

While enumerating protocols implemented by the SCMI platform using
BASE_DISCOVER_LIST_PROTOCOLS, the number of returned protocols is
currently validated in an improper way since the check employs a sum
between unsigned integers that could overflow and cause the check itself
to be silently bypassed if the returned value 'loop_num_ret' is big
enough.

Fix the validation avoiding the addition.

Link: https://lore.kernel.org/r/20220330150551.2573938-4-cristian.marussi@arm.com
Fixes: b6f20ff8bd ("firmware: arm_scmi: add common infrastructure and support for base protocol")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-09 10:21:15 +02:00
Cristian Marussi
5637129712 firmware: arm_scmi: Fix sorting of retrieved clock rates
[ Upstream commit 23274739a5b6166f74d8d9cb5243d7bf6b46aab9 ]

During SCMI Clock protocol initialization, after having retrieved from the
SCMI platform all the available discrete rates for a specific clock, the
clock rates array is sorted, unfortunately using a pointer to its end as
a base instead of its start, so that sorting does not work.

Fix invocation of sort() passing as base a pointer to the start of the
retrieved clock rates array.

Link: https://lore.kernel.org/r/20220318092813.49283-1-cristian.marussi@arm.com
Fixes: dccec73de9 ("firmware: arm_scmi: Keep the discrete clock rates sorted")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-20 09:23:10 +02:00
Alyssa Ross
8b8ac465bf firmware: arm_scmi: Remove space in MODULE_ALIAS name
commit 1ba603f56568c3b4c2542dfba07afa25f21dcff3 upstream.

modprobe can't handle spaces in aliases. Get rid of it to fix the issue.

Link: https://lore.kernel.org/r/20220211102704.128354-1-sudeep.holla@arm.com
Fixes: aa4f886f38 ("firmware: arm_scmi: add basic driver infrastructure for SCMI")
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Alyssa Ross <hi@alyssa.is>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-08 19:09:35 +01:00
Peng Fan
c9ba7864d3 firmware: arm_scmi: pm: Propagate return value to caller
[ Upstream commit 1446fc6c678e8d8b31606a4b877abe205f344b38 ]

of_genpd_add_provider_onecell may return error, so let's propagate
its return value to caller

Link: https://lore.kernel.org/r/20211116064227.20571-1-peng.fan@oss.nxp.com
Fixes: 898216c97e ("firmware: arm_scmi: add device power domain support using genpd")
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-12-01 09:19:03 +01:00
Cristian Marussi
1b1a00b13c firmware: arm_scmi: Add delayed response status check
commit f1748b1ee1fa0fd1a074504045b530b62f949188 upstream.

A successfully received delayed response could anyway report a failure at
the protocol layer in the message status field.

Add a check also for this error condition.

Link: https://lore.kernel.org/r/20210608103056.3388-1-cristian.marussi@arm.com
Fixes: 58ecdf03db ("firmware: arm_scmi: Add support for asynchronous commands and delayed response")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-08 09:05:24 +02:00
Sudeep Holla
93ef561406 firmware: arm_scmi: Ensure drivers provide a probe function
commit 5e469dac326555d2038d199a6329458cc82a34e5 upstream.

The bus probe callback calls the driver callback without further
checking. Better be safe than sorry and refuse registration of a driver
without a probe function to prevent a NULL pointer exception.

Link: https://lore.kernel.org/r/20210624095059.4010157-2-sudeep.holla@arm.com
Fixes: 933c504424 ("firmware: arm_scmi: add scmi protocol bus to enumerate protocol devices")
Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Tested-by: Cristian Marussi <cristian.marussi@arm.com>
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-08 09:05:23 +02:00
Cristian Marussi
fe5fe0b1c8 firmware: arm_scmi: Fix range check for the maximum number of pending messages
[ Upstream commit bdb8742dc6f7c599c3d61959234fe4c23638727b ]

SCMI message headers carry a sequence number and such field is sized to
allow for MSG_TOKEN_MAX distinct numbers; moreover zero is not really an
acceptable maximum number of pending in-flight messages.

Fix accordingly the checks performed on the value exported by transports
in scmi_desc.max_msg

Link: https://lore.kernel.org/r/20210712141833.6628-3-cristian.marussi@arm.com
Reported-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
[sudeep.holla: updated the patch title and error message]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-31 08:16:12 +02:00
Sudeep Holla
8f8e5475a3 firmware: arm_scmi: Fix possible scmi_linux_errmap buffer overflow
[ Upstream commit 7a691f16ccad05d770f813d9c4b4337a30c6d63f ]

The scmi_linux_errmap buffer access index is supposed to depend on the
array size to prevent element out of bounds access. It uses SCMI_ERR_MAX
to check bounds but that can mismatch with the array size. It also
changes the success into -EIO though scmi_linux_errmap is never used in
case of success, it is expected to work for success case too.

It is slightly confusing code as the negative of the error code
is used as index to the buffer. Fix it by negating it at the start and
make it more readable.

Link: https://lore.kernel.org/r/20210707135028.1869642-1-sudeep.holla@arm.com
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-31 08:16:12 +02:00
Sudeep Holla
15d727c044 firmware: arm_scmi: Fix the build when CONFIG_MAILBOX is not selected
[ Upstream commit ab7766b72855e6a68109b915d071181b93086e29 ]

0day CI kernel test robot reported following build error with randconfig

aarch64-linux-ld: drivers/firmware/arm_scmi/driver.o:(.rodata+0x1e0):
		undefined reference to `scmi_mailbox_desc'

Fix the error by adding CONFIG_MAILBOX dependency for scmi_mailbox_desc.

Link: https://lore.kernel.org/r/20210603072631.1660963-1-sudeep.holla@arm.com
Cc: Etienne Carriere <etienne.carriere@linaro.org>
Cc: Cristian Marussi <cristian.marussi@arm.com>
Reviewed-by: Etienne Carriere <etienne.carriere@linaro.org>
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Tested-by: Cristian Marussi <cristian.marussi@arm.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-25 14:36:14 +02:00
Etienne Carriere
b4009ea92f firmware: arm_scmi: Add SMCCC discovery dependency in Kconfig
[ Upstream commit c05b07963e965ae34e75ee8c33af1095350cd87e ]

ARM_SCMI_PROTOCOL depends on either MAILBOX or HAVE_ARM_SMCCC_DISCOVERY,
not MAILBOX alone. Fix the depedency in Kconfig file and driver to
reflect the same.

Link: https://lore.kernel.org/r/20210521134055.24271-1-etienne.carriere@linaro.org
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
[sudeep.holla: Minor tweaks to subject and change log]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-25 14:36:14 +02:00
Cristian Marussi
4b4c61049e firmware: arm_scmi: Reset Rx buffer to max size during async commands
[ Upstream commit 0cb7af474e0dbb2f500c67aa62b6db9fafa74de2 ]

During an async commands execution the Rx buffer length is at first set
to max_msg_sz when the synchronous part of the command is first sent.
However once the synchronous part completes the transport layer waits
for the delayed response which will be processed using the same xfer
descriptor initially allocated. Since synchronous response received at
the end of the xfer will shrink the Rx buffer length to the effective
payload response length, it needs to be reset again.

Raise the Rx buffer length again to max_msg_sz before fetching the
delayed response to ensure full response is read correctly from the
shared memory.

Link: https://lore.kernel.org/r/20210601102421.26581-2-cristian.marussi@arm.com
Fixes: 58ecdf03db ("firmware: arm_scmi: Add support for asynchronous commands and delayed response")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
[sudeep.holla: moved reset to scmi_handle_response as it could race with
               do_xfer_with_response]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-20 16:05:56 +02:00
Cristian Marussi
1173e48b16 firmware: arm_scmi: Fix call site of scmi_notification_exit
[ Upstream commit a90b6543bf062d65292b2c76f1630507d1c9d8ec ]

Call scmi_notification_exit() only when SCMI platform driver instance has
been really successfully removed.

Link: https://lore.kernel.org/r/20210112191326.29091-1-cristian.marussi@arm.com
Fixes: 6b8a69131d ("firmware: arm_scmi: Enable notification core")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
[sudeep.holla: Move the call outside the list mutex locking]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-04 11:37:23 +01:00
Qinglang Miao
2fa9f29441 firmware: arm_scmi: Fix missing destroy_workqueue()
[ Upstream commit 6bbdb46c4b1bd57839c9c0a110bd81b0be0a4046 ]

destroy_workqueue is required before the return from scmi_notification_init
in case devm_kcalloc fails to allocate registered_protocols. Fix this by
simply moving registered_protocols allocation before alloc_workqueue.

Link: https://lore.kernel.org/r/20201110074221.41235-1-miaoqinglang@huawei.com
Fixes: bd31b24969 ("firmware: arm_scmi: Add notification dispatch and delivery")
Suggested-by: Cristian Marussi <cristian.marussi@arm.com>
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:53:09 +01:00
Florian Fainelli
b9ceca6be4 firmware: arm_scmi: Fix duplicate workqueue name
When more than a single SCMI device are present in the system, the
creation of the notification workqueue with the WQ_SYSFS flag will lead
to the following sysfs duplicate node warning:

 sysfs: cannot create duplicate filename '/devices/virtual/workqueue/scmi_notify'
 CPU: 0 PID: 20 Comm: kworker/0:1 Not tainted 5.9.0-gdf4dd84a3f7d #29
 Hardware name: Broadcom STB (Flattened Device Tree)
 Workqueue: events deferred_probe_work_func
 Backtrace:
   show_stack + 0x20/0x24
   dump_stack + 0xbc/0xe0
   sysfs_warn_dup + 0x70/0x80
   sysfs_create_dir_ns + 0x15c/0x1a4
   kobject_add_internal + 0x140/0x4d0
   kobject_add + 0xc8/0x138
   device_add + 0x1dc/0xc20
   device_register + 0x24/0x28
   workqueue_sysfs_register + 0xe4/0x1f0
   alloc_workqueue + 0x448/0x6ac
   scmi_notification_init + 0x78/0x1dc
   scmi_probe + 0x268/0x4fc
   platform_drv_probe + 0x70/0xc8
   really_probe + 0x184/0x728
   driver_probe_device + 0xa4/0x278
   __device_attach_driver + 0xe8/0x148
   bus_for_each_drv + 0x108/0x158
   __device_attach + 0x190/0x234
   device_initial_probe + 0x1c/0x20
   bus_probe_device + 0xdc/0xec
   deferred_probe_work_func + 0xd4/0x11c
   process_one_work + 0x420/0x8f0
   worker_thread + 0x4fc/0x91c
   kthread + 0x21c/0x22c
   ret_from_fork + 0x14/0x20
 kobject_add_internal failed for scmi_notify with -EEXIST, don't try to
 	register things with the same name in the same directory.
 arm-scmi brcm_scmi@1: SCMI Notifications - Initialization Failed.
 arm-scmi brcm_scmi@1: SCMI Notifications NOT available.
 arm-scmi brcm_scmi@1: SCMI Protocol v1.0 'brcm-scmi:' Firmware version 0x1

Fix this by using dev_name(handle->dev) which guarantees that the name is
unique and this also helps correlate which notification workqueue corresponds
to which SCMI device instance.

Link: https://lore.kernel.org/r/20201014021737.287340-1-f.fainelli@gmail.com
Fixes: bd31b24969 ("firmware: arm_scmi: Add notification dispatch and delivery")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
[sudeep.holla: trimmed backtrace to remove all unwanted hexcodes and timestamps]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-10-14 18:42:41 +01:00
Cristian Marussi
c7821c2d9c firmware: arm_scmi: Fix locking in notifications
When a protocol registers its events, the notification core takes care
to rescan the hashtable of pending event handlers and activate all the
possibly existent handlers referring to any of the events that are just
registered by the new protocol. When a pending handler becomes active
the core requests and enables the corresponding events in the SCMI
firmware.

If, for whatever reason, the enable fails, such invalid event handler
must be finally removed and freed. Let us ensure to use the
scmi_put_active_handler() helper which handles properly the needed
additional locking.

Failing to properly acquire all the needed mutexes exposes a race that
leads to the following splat being observed:

 WARNING: CPU: 0 PID: 388 at lib/refcount.c:28 refcount_warn_saturate+0xf8/0x148
 Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno Development
 	Platform, BIOS EDK II Jun 30 2020
 pstate: 40000005 (nZcv daif -PAN -UAO BTYPE=--)
 pc : refcount_warn_saturate+0xf8/0x148
 lr : refcount_warn_saturate+0xf8/0x148
 Call trace:
  refcount_warn_saturate+0xf8/0x148
  scmi_put_handler_unlocked.isra.10+0x204/0x208
  scmi_put_handler+0x50/0xa0
  scmi_unregister_notifier+0x1bc/0x240
  scmi_notify_tester_remove+0x4c/0x68 [dummy_scmi_consumer]
  scmi_dev_remove+0x54/0x68
  device_release_driver_internal+0x114/0x1e8
  driver_detach+0x58/0xe8
  bus_remove_driver+0x88/0xe0
  driver_unregister+0x38/0x68
  scmi_driver_unregister+0x1c/0x28
  scmi_drv_exit+0x1c/0xae0 [dummy_scmi_consumer]
  __arm64_sys_delete_module+0x1a4/0x268
  el0_svc_common.constprop.3+0x94/0x178
  do_el0_svc+0x2c/0x98
  el0_sync_handler+0x148/0x1a8
  el0_sync+0x158/0x180

Link: https://lore.kernel.org/r/20201013133109.49821-1-cristian.marussi@arm.com
Fixes: e7c215f358 ("firmware: arm_scmi: Add notification callbacks-registration")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-10-14 18:42:41 +01:00
Sudeep Holla
9724722fde firmware: arm_scmi: Add missing Rx size re-initialisation
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>
2020-10-13 10:01:47 +01:00
Etienne Carriere
7adb2c8aaa firmware: arm_scmi: Expand SMC/HVC message pool to more than one
SMC/HVC can transmit only one message at the time as the shared memory
needs to be protected and the calls are synchronous.

However, in order to allow multiple threads to send SCMI messages
simultaneously, we need a larger poll of memory.

Let us just use value of 20 to keep it in sync mailbox transport
implementation. Any other value must work perfectly.

Link: https://lore.kernel.org/r/20201008143722.21888-4-etienne.carriere@linaro.org
Fixes: 1dc6558062 ("firmware: arm_scmi: Add smc/hvc transport")
Cc: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
[sudeep.holla: reworded the commit message to indicate the practicality]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-10-12 15:10:42 +01:00
Etienne Carriere
45b9e04d5b firmware: arm_scmi: Fix ARCH_COLD_RESET
The defination for ARCH_COLD_RESET is wrong. Let us fix it according to
the SCMI specification.

Link: https://lore.kernel.org/r/20201008143722.21888-5-etienne.carriere@linaro.org
Fixes: 95a15d80aa ("firmware: arm_scmi: Add RESET protocol in SCMI v2.0")
Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-10-12 14:05:12 +01:00
Sudeep Holla
66d90f6ece firmware: arm_scmi: Enable building as a single module
Now, with all the plumbing in place to enable building scmi as a module
instead of built-in modules, let us enable the same.

Link: https://lore.kernel.org/r/20200907195046.56615-5-sudeep.holla@arm.com
Tested-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-09-14 07:31:03 +01:00
Sudeep Holla
1eaf18e35a firmware: arm_scmi: Move scmi protocols registration into the driver
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>
2020-09-14 07:30:55 +01:00
Sudeep Holla
5a2f0a0bdf firmware: arm_scmi: Move scmi bus init and exit calls into the driver
In preparation to enable building scmi as a single module, let us move
the scmi bus {de-,}initialisation call into the driver.

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/20200907195046.56615-3-sudeep.holla@arm.com
Tested-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-09-14 07:30:48 +01:00
Sudeep Holla
6ed6c55823 firmware: arm_scmi: Fix NULL pointer dereference in mailbox_chan_free
scmi_mailbox is obtained from cinfo->transport_info and the first
call to mailbox_chan_free frees the channel and sets cinfo->transport_info
to NULL. Care is taken to check for non NULL smbox->chan but smbox can
itself be NULL. Fix it by checking for it without which, kernel crashes
with below NULL pointer dereference and eventually kernel panic.

   Unable to handle kernel NULL pointer dereference at
   		virtual address 0000000000000038
   Modules linked in: scmi_module(-)
   Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno
   		Development Platform, BIOS EDK II Sep  2 2020
   pstate: 80000005 (Nzcv daif -PAN -UAO BTYPE=--)
   pc : mailbox_chan_free+0x2c/0x70 [scmi_module]
   lr : idr_for_each+0x6c/0xf8
   Call trace:
    mailbox_chan_free+0x2c/0x70 [scmi_module]
    idr_for_each+0x6c/0xf8
    scmi_remove+0xa8/0xf0 [scmi_module]
    platform_drv_remove+0x34/0x58
    device_release_driver_internal+0x118/0x1f0
    driver_detach+0x58/0xe8
    bus_remove_driver+0x64/0xe0
    driver_unregister+0x38/0x68
    platform_driver_unregister+0x1c/0x28
    scmi_driver_exit+0x38/0x44 [scmi_module]
   ---[ end trace 17bde19f50436de9 ]---
   Kernel panic - not syncing: Fatal exception
   SMP: stopping secondary CPUs
   Kernel Offset: 0x1d0000 from 0xffff800010000000
   PHYS_OFFSET: 0x80000000
   CPU features: 0x0240022,25806004
   Memory Limit: none
   ---[ end Kernel panic - not syncing: Fatal exception ]---

Link: https://lore.kernel.org/r/20200908112611.31515-1-sudeep.holla@arm.com
Fixes: 5c8a47a5a9 ("firmware: arm_scmi: Make scmi core independent of the transport type")
Cc: Cristian Marussi <cristian.marussi@arm.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Cristian Marussi <cristian.marussi@arm.com>
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-09-09 10:01:21 +01:00
Cristian Marussi
481f6ccf39 firmware: arm_scmi: Add SCMI device for system power protocol
Add SCMI device for system power protocol by just adding the name "syspower"
to the list of supported core protocol devices.

Link: https://lore.kernel.org/r/20200907174657.32466-3-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-09-08 16:02:17 +01:00
Cristian Marussi
a880305512 firmware: arm_scmi: Add system power protocol support
Add bare protocol support for SCMI system power protocol as needed by
an OSPM agent: basic initialization and SYSTEM_POWER_STATE_NOTIFIER
core notification support.

No event-handling logic is attached to such notification..

Link: https://lore.kernel.org/r/20200907174657.32466-2-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-09-08 16:00:55 +01:00
Rikard Falkeborn
3de7b83017 firmware: arm_scmi: Constify static scmi-ops
These are never modified, so make them const to allow the compiler to
put them in read-only memory.

Link: https://lore.kernel.org/r/20200906230452.33410-4-rikard.falkeborn@gmail.com
Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-09-07 12:43:27 +01:00
Sudeep Holla
a0edee6350 firmware: arm_scmi: Use NULL instead of integer 0 for rate pointer
Kbuild test robot reports the following sparse warning:

drivers/firmware/arm_scmi/clock.c:142:21:
	sparse: Using plain integer as NULL pointer

Use NULL pointer instead of integer 0 for rate pointer and fix the
warning.

Link: https://lore.kernel.org/r/20200717140405.17905-1-sudeep.holla@arm.com
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2020-07-17 16:06:54 +02:00
Cristian Marussi
72a5eb9d9c firmware: arm_scmi: Remove fixed size fields from reports/scmi_event_header
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>
2020-07-13 09:40:21 +01:00
Cristian Marussi
33ee97f823 firmware: arm_scmi: Remove unneeded __packed attribute
Remove __packed attribute from struct scmi_event_header.

Link: https://lore.kernel.org/r/20200710133919.39792-2-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-07-13 09:40:21 +01:00
Sudeep Holla
a4ee9d0194 firmware: arm_scmi: Provide a missing function param description
gcc as well as clang now produce warnings for missing kerneldoc function
parameter.

Fix the following W=1 kernel build warning:

drivers/firmware/arm_scmi/smc.c:32:
 warning: Function parameter or member 'shmem_lock' not described in 'scmi_smc'

Link: https://lore.kernel.org/r/20200709153155.22573-1-sudeep.holla@arm.com
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-07-13 09:40:21 +01:00
Sudeep Holla
dccec73de9 firmware: arm_scmi: Keep the discrete clock rates sorted
Instead of relying on the firmware to keep the clock rates sorted, let
us sort the list. This is not essential for clock layer but it helps
to find the min and max rates easily from the list.

Link: https://lore.kernel.org/r/20200709081705.46084-1-sudeep.holla@arm.com
Fixes: 5f6c6430e9 ("firmware: arm_scmi: add initial support for clock protocol")
Reported-and-tested-by: Dien Pham <dien.pham.ry@renesas.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-07-10 12:06:27 +01:00
Cristian Marussi
585dfab3fb firmware: arm_scmi: Add base notifications support
Make SCMI base protocol register with the notification core.

Link: https://lore.kernel.org/r/20200701155348.52864-10-cristian.marussi@arm.com
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-07-01 17:07:26 +01:00
Cristian Marussi
469ca1822d firmware: arm_scmi: Add reset notifications support
Make SCMI reset protocol register with the notification core.

Link: https://lore.kernel.org/r/20200701155348.52864-9-cristian.marussi@arm.com
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-07-01 17:07:26 +01:00
Cristian Marussi
128e3e9311 firmware: arm_scmi: Add sensor notifications support
Make SCMI sensor protocol register with the notification core.

Link: https://lore.kernel.org/r/20200701155348.52864-8-cristian.marussi@arm.com
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-07-01 17:07:26 +01:00
Cristian Marussi
fb5086dc47 firmware: arm_scmi: Add perf notifications support
Make SCMI perf protocol register with the notification core.

Link: https://lore.kernel.org/r/20200701155348.52864-7-cristian.marussi@arm.com
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-07-01 17:07:26 +01:00
Cristian Marussi
e27077bc04 firmware: arm_scmi: Add power notifications support
Make SCMI power protocol register with the notification core.

Link: https://lore.kernel.org/r/20200701155348.52864-6-cristian.marussi@arm.com
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-07-01 17:07:26 +01:00
Cristian Marussi
6b8a69131d firmware: arm_scmi: Enable notification core
Initialize and enable SCMI notifications core support during bus/driver
probe phase, so that protocols can start registering their supported
events during their initialization.

Link: https://lore.kernel.org/r/20200701155348.52864-5-cristian.marussi@arm.com
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-07-01 17:07:26 +01:00
Cristian Marussi
bd31b24969 firmware: arm_scmi: Add notification dispatch and delivery
Add the core SCMI notifications dispatch and delivery support logic
which is able to dispatch well-known received events from the Rx
interrupt handler to the dedicated deferred worker. From there, it will
deliver the events to the registered users' callbacks.

Dispatch and delivery support is just added here, still not enabled.

Link: https://lore.kernel.org/r/20200701155348.52864-4-cristian.marussi@arm.com
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-07-01 17:07:25 +01:00
Cristian Marussi
e7c215f358 firmware: arm_scmi: Add notification callbacks-registration
Add the core SCMI notifications callbacks-registration support: allow
users to register their own callbacks against the desired events.

Whenever a registration request is issued against a still non existent
event, mark such request as pending for later processing, in order to
account for possible late initializations of SCMI Protocols associated
to loadable drivers.

Link: https://lore.kernel.org/r/20200701155348.52864-3-cristian.marussi@arm.com
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-07-01 17:07:25 +01:00
Cristian Marussi
1fc2dd1864 firmware: arm_scmi: Add notification protocol-registration
Add the core SCMI notifications protocol-registration support: allow
protocols to register their own set of supported events, during their
initialization phase. Notification core can track multiple platform
instances by their handles.

Link: https://lore.kernel.org/r/20200701155348.52864-2-cristian.marussi@arm.com
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-07-01 17:07:25 +01:00
Cristian Marussi
e0f1a30cf1 firmware: arm_scmi: Fix SCMI genpd domain probing
When, at probe time, an SCMI communication failure inhibits the capacity
to query power domains states, such domains should be skipped.

Registering partially initialized SCMI power domains with genpd will
causes kernel panic.

 arm-scmi timed out in resp(caller: scmi_power_state_get+0xa4/0xd0)
 scmi-power-domain scmi_dev.2: failed to get state for domain 9
 Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
 Mem abort info:
   ESR = 0x96000006
   EC = 0x25: DABT (current EL), IL = 32 bits
   SET = 0, FnV = 0
   EA = 0, S1PTW = 0
 Data abort info:
   ISV = 0, ISS = 0x00000006
   CM = 0, WnR = 0
 user pgtable: 4k pages, 48-bit VAs, pgdp=00000009f3691000
 [0000000000000000] pgd=00000009f1ca0003, p4d=00000009f1ca0003, pud=00000009f35ea003, pmd=0000000000000000
 Internal error: Oops: 96000006 [#1] PREEMPT SMP
 CPU: 2 PID: 381 Comm: bash Not tainted 5.8.0-rc1-00011-gebd118c2cca8 #2
 Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno Development Platform, BIOS EDK II Jan  3 2020
 Internal error: Oops: 96000006 [#1] PREEMPT SMP
 pstate: 80000005 (Nzcv daif -PAN -UAO BTYPE=--)
 pc : of_genpd_add_provider_onecell+0x98/0x1f8
 lr : of_genpd_add_provider_onecell+0x48/0x1f8
 Call trace:
  of_genpd_add_provider_onecell+0x98/0x1f8
  scmi_pm_domain_probe+0x174/0x1e8
  scmi_dev_probe+0x90/0xe0
  really_probe+0xe4/0x448
  driver_probe_device+0xfc/0x168
  device_driver_attach+0x7c/0x88
  bind_store+0xe8/0x128
  drv_attr_store+0x2c/0x40
  sysfs_kf_write+0x4c/0x60
  kernfs_fop_write+0x114/0x230
  __vfs_write+0x24/0x50
  vfs_write+0xbc/0x1e0
  ksys_write+0x70/0xf8
  __arm64_sys_write+0x24/0x30
  el0_svc_common.constprop.3+0x94/0x160
  do_el0_svc+0x2c/0x98
  el0_sync_handler+0x148/0x1a8
  el0_sync+0x158/0x180

Do not register any power domain that failed to be queried with genpd.

Fixes: 898216c97e ("firmware: arm_scmi: add device power domain support using genpd")
Link: https://lore.kernel.org/r/20200619220330.12217-1-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-06-30 14:08:18 +01:00
Sudeep Holla
d764282377 firmware: arm_scmi: Use HAVE_ARM_SMCCC_DISCOVERY instead of ARM_PSCI_FW
Commit e5bfb21d98 ("firmware: smccc: Add HAVE_ARM_SMCCC_DISCOVERY to
identify SMCCC v1.1 and above") introduced new config option to identify
the availability of SMCCC discoverability of version and features
transparently hiding the indirect dependency on ARM_PSCI_FW.

Commit 5a897e3ab4 ("firmware: arm_scmi: fix psci dependency") just
worked around the build dependency making SCMI SMC/HVC transport depend
on ARM_PSCI_FW at the time. Since it really just relies on SMCCC directly
and not on ARM_PSCI_FW, let us move to use CONFIG_HAVE_ARM_SMCCC_DISCOVERY
instead of CONFIG_ARM_PSCI_FW.

Link: https://lore.kernel.org/r/20200625101937.51939-1-sudeep.holla@arm.com
Cc: Peng Fan <peng.fan@nxp.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-06-30 14:08:10 +01:00
Nicola Mazzucato
1909872ff2 firmware: arm_scmi: Add fast_switch_possible() interface
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>
2020-06-30 14:07:15 +01:00
Sudeep Holla
bad0d73b65 firmware: arm_scmi: Use signed integer to report transfer status
Currently the trace event 'scmi_xfer_end' reports the status of the
transfer using the unsigned status field read from the firmware which
may not be easy to interpret. It may also miss to emit any timeouts
that happen in the driver resulting in emitting garbage in the status
field in those scenarios.

Let us use signed integer so that error values are emitted out after
they are mapped from firmware error formats to standard linux error
codes. While at this, also include any timeouts in the driver itself.

Link: https://lore.kernel.org/r/20200609134503.55860-1-sudeep.holla@arm.com
Cc: Jim Quinlan <james.quinlan@broadcom.com>
Cc: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-06-30 14:07:08 +01:00
Sudeep Holla
5a897e3ab4 firmware: arm_scmi: fix psci dependency
When CONFIG_ARM_PSCI_FW is disabled but CONFIG_HAVE_ARM_SMCCC is enabled,
arm-scmi runs into a link failure:

arm-linux-gnueabi-ld: drivers/firmware/arm_scmi/smc.o: in function `smc_send_message':
smc.c:(.text+0x200): undefined reference to `arm_smccc_1_1_get_conduit'

Change from HAVE_ARM_SMCCC to ARM_PSCI_FW config dependency for now.
We rely on PSCI bindings anyways for the conduit and this should be
fine.

Link: https://lore.kernel.org/r/20200507144905.11397-1-sudeep.holla@arm.com
Fixes: 1dc6558062 ("firmware: arm_scmi: Add smc/hvc transport")
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-05-07 16:28:56 +01:00