FFA_NOTIFICATION_INFO_GET retrieves information about pending
notifications. Notifications can be either global or per VCPU. Global
notifications are reported with the partition ID only in the list of
endpoints with pending notifications. ffa_notification_info_get()
incorrectly expect no ID at all for global notifications. Fix this by
checking for ID = 1 instead of ID = 0.
Fixes: 3522be48d8 ("firmware: arm_ffa: Implement the NOTIFICATION_INFO_GET interface")
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Reviewed-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Link: https://lore.kernel.org/r/20240311110700.2367142-1-jens.wiklander@linaro.org
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
This is the usual mix of updates for drivers that are used on (mostly
ARM) SoCs with no other top-level subsystem tree, including:
- The SCMI firmware subsystem gains support for version 3.2 of the
specification and updates to the notification code.
- Feature updates for Tegra and Qualcomm platforms for added
hardware support.
- A number of platforms get soc_device additions for identifying newly
added chips from Renesas, Qualcomm, Mediatek and Google.
- Trivial improvements for firmware and memory drivers amongst
others, in particular 'const' annotations throughout multiple
subsystems.
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Merge tag 'soc-drivers-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull ARM SoC driver updates from Arnd Bergmann:
"This is the usual mix of updates for drivers that are used on (mostly
ARM) SoCs with no other top-level subsystem tree, including:
- The SCMI firmware subsystem gains support for version 3.2 of the
specification and updates to the notification code
- Feature updates for Tegra and Qualcomm platforms for added hardware
support
- A number of platforms get soc_device additions for identifying
newly added chips from Renesas, Qualcomm, Mediatek and Google
- Trivial improvements for firmware and memory drivers amongst
others, in particular 'const' annotations throughout multiple
subsystems"
* tag 'soc-drivers-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (96 commits)
tee: make tee_bus_type const
soc: qcom: aoss: add missing kerneldoc for qmp members
soc: qcom: geni-se: drop unused kerneldoc struct geni_wrapper param
soc: qcom: spm: fix building with CONFIG_REGULATOR=n
bus: ti-sysc: constify the struct device_type usage
memory: stm32-fmc2-ebi: keep power domain on
memory: stm32-fmc2-ebi: add MP25 RIF support
memory: stm32-fmc2-ebi: add MP25 support
memory: stm32-fmc2-ebi: check regmap_read return value
dt-bindings: memory-controller: st,stm32: add MP25 support
dt-bindings: bus: imx-weim: convert to YAML
watchdog: s3c2410_wdt: use exynos_get_pmu_regmap_by_phandle() for PMU regs
soc: samsung: exynos-pmu: Add regmap support for SoCs that protect PMU regs
MAINTAINERS: Update SCMI entry with HWMON driver
MAINTAINERS: samsung: gs101: match patches touching Google Tensor SoC
memory: tegra: Fix indentation
memory: tegra: Add BPMP and ICC info for DLA clients
memory: tegra: Correct DLA client names
dt-bindings: memory: renesas,rpc-if: Document R-Car V4M support
firmware: arm_scmi: Update the supported clock protocol version
...
Now that the driver core can properly handle constant struct bus_type,
move the ffa_bus_type variable to be a constant structure as well,
placing it into read-only memory which can not be modified at runtime.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20240211-bus_cleanup-firmware2-v1-1-1851c92c7be7@marliere.net
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Make ffa_setup_partitions() fail, cleanup and return an error when the Host
partition setup fails: in such a case ffa_init() itself will fail.
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20240108-ffa_fixes_6-8-v1-6-75bf7035bc50@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
While adding new partitions descriptors to the XArray the outcome of the
stores should be checked and, in particular, it has also to be ensured
that an existing entry with the same index was not already present, since
partitions IDs are expected to be unique.
Use xa_insert() instead of xa_store() since it returns -EBUSY when the
index is already in use and log an error when that happens.
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20240108-ffa_fixes_6-8-v1-5-75bf7035bc50@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
On cleanup iterate the XArrays with xa_for_each() and remove the existent
entries with xa_erase(), finally destroy the XArray itself.
Remove partition_count field from drv_info since no more used anywhwere.
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20240108-ffa_fixes_6-8-v1-4-75bf7035bc50@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Add a check to verify the result of xa_load() during the partition
lookups done while registering/unregistering the scheduler receiver
interrupt callbacks and while executing the main scheduler receiver
interrupt callback handler.
Fixes: 0184450b8b ("firmware: arm_ffa: Add schedule receiver callback mechanism")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20240108-ffa_fixes_6-8-v1-3-75bf7035bc50@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Add the missing rwlock initialization for the FF-A partition associated
the driver in ffa_setup_partitions(). It will the primary scheduler
partition in the host or the VM partition in the virtualised environment.
IOW, it corresponds to the partition with VM ID == drv_info->vm_id.
Fixes: 1b6bf41b7a ("firmware: arm_ffa: Add notification handling mechanism")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20240108-ffa_fixes_6-8-v1-2-75bf7035bc50@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
To parse the retrieved ID lists appropriately in
ffa_notification_info_get() the ids_processed variable should not
be pre-incremented - we are dropping an identifier at the
beginning of the list.
Fix it by using the post-increment operator to increment the number
of processed IDs.
Fixes: 3522be48d8 ("firmware: arm_ffa: Implement the NOTIFICATION_INFO_GET interface")
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/20231108111549.155974-1-lpieralisi@kernel.org
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Arry of pointer to struct ffa_dev_part_info needs to be allocated to
fetch the pointers stored in XArray. However, currently we allocate the
entire structure instead of just pointers.
Fix the allocation size. This will also eliminate the below Smatch
istatic checker warning:
| drivers/firmware/arm_ffa/driver.c:1251 ffa_partitions_cleanup()
| warn: double check that we're allocating correct size: 8 vs 88
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/all/0e8ddbca-d9da-4a3b-aae3-328993b62ba2@moroto.mountain
Link: https://lore.kernel.org/r/20231031141335.3077026-1-sudeep.holla@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
We allow the FF-A to be initialised successfully even when notification
fails. When the notification fails, ffa_notifications_cleanup() gets
called on the failure path.
However, the driver information about the notifications like the irq,
workqueues and cpu hotplug state for enabling and disabling percpu IRQ
are not cleared. This may result in unexpected behaviour during CPU
hotplug because of percpu IRQ being enabled and disabled or during the
driver removal when ffa_notifications_cleanup() gets executed again.
Fix the FFA notifications cleanup path by clearing all the notification
related driver information.
Link: https://lore.kernel.org/r/20231024-ffa-notification-fixes-v1-4-d552c0ec260d@arm.com
Tested-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
We need to check if the FF-A notifications are enabled or not in all
the notification operations that are accessible for the FF-A device
from the FF-A driver. This helps to avoid making calls to the FF-A
firmware even if the notification setup has failed.
Link: https://lore.kernel.org/r/20231024-ffa-notification-fixes-v1-3-d552c0ec260d@arm.com
Tested-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Currently the notifications are setup of the partitions are probed and
FF-A devices are added on the FF-A bus. The FF-A driver probe can be
called even before the FF-A notification setup happens which is wrong
and may result in failure or misbehaviour in the FF-A partition device
probe.
In order to ensure the FF-A notifications are setup before the FF-A
devices are probed, let us move the FF-A partition setup after the
completion of FF-A notification setup.
Link: https://lore.kernel.org/r/20231024-ffa-notification-fixes-v1-2-d552c0ec260d@arm.com
Tested-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
FF-A notifications are optional feature in the specification. Currently
we allow to continue if the firmware reports no support for the
notifications. However, we fail to continue and complete the FF-A
driver initialisation if the notification setup fails for any reason.
Let us allow the FF-A driver to complete the initialisation even if the
notification fails to setup. We will just flag the error and continue
to provide other features in the driver.
Link: https://lore.kernel.org/r/20231024-ffa-notification-fixes-v1-1-d552c0ec260d@arm.com
Tested-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Update memory transaction descriptor structure to accommodate couple of
new entries in v1.1 which were previously marked reserved and MBZ(must
be zero).
It also removes the flexible array member ep_mem_access in the memory
transaction descriptor structure as it need not be at fixed offset.
Also update ffa_mem_desc_offset() accessor to handle both old and new
formats of memory transaction descriptors.
The updated ffa_mem_region structure aligns with new format in v1.1 and
hence the driver/user must take care not to use members beyond and
including ep_mem_offset when using the old format.
Link: https://lore.kernel.org/r/20231005-ffa_v1-1_notif-v4-16-cddd3237809c@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
In preparation to add support to the new memory transaction descriptor,
the ep_mem_access member needs to be removed and hence even the macro
COMPOSITE_OFFSET(). Let us switch to using the new ffa_mem_desc_offset()
accessor in ffa_setup_and_transmit().
This will enable adding the support for new format transparently without
any changes here again.
Link: https://lore.kernel.org/r/20231005-ffa_v1-1_notif-v4-15-cddd3237809c@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The computation of endpoint memory access descriptor's composite memory
region descriptor offset is using COMPOSITE_CONSTITUENTS_OFFSET which is
unnecessary complicated. Composite memory region descriptor always follow
the endpoint memory access descriptor array and hence it is computed
accordingly. COMPOSITE_CONSTITUENTS_OFFSET is useless and wrong for any
input other than endpoint memory access descriptor count.
Let us drop the usage of COMPOSITE_CONSTITUENTS_OFFSET to simplify the
computation of total transmit and fragment length in the memory
transactions.
Link: https://lore.kernel.org/r/20231005-ffa_v1-1_notif-v4-13-cddd3237809c@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
With all the necessary plumbing in place, let us add handling the
notifications as part of schedule receiver interrupt handler. In order
to do so, we need to just register scheduling callback on behalf of the
driver partition.
Link: https://lore.kernel.org/r/20231005-ffa_v1-1_notif-v4-12-cddd3237809c@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The framework provides an interface to the sender endpoint to specify
the notification to signal to the receiver endpoint. A sender signals
a notification by requesting its partition manager to set the
corresponding bit in the notifications bitmap of the receiver.
Expose the ability to send a notification to another partition.
Link: https://lore.kernel.org/r/20231005-ffa_v1-1_notif-v4-11-cddd3237809c@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Enable client drivers to register a callback function that will be
called when one or more notifications are pending for a target
partition as part of schedule receiver interrupt handling.
Link: https://lore.kernel.org/r/20231005-ffa_v1-1_notif-v4-9-cddd3237809c@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The Framework uses the schedule receiver interrupt to inform the
receiver’s scheduler that the receiver must be run to handle a pending
notification. A receiver’s scheduler can obtain the description of the
schedule receiver interrupt by invoking the FFA_FEATURES interface.
The delivery of the physical schedule receiver interrupt from the secure
state to the non-secure state depends upon the state of the interrupt
controller as configured by the hypervisor.
The schedule seceiver interrupt is assumed to be a SGI. The Arm GIC
specification defines 16 SGIs. It recommends that they are equally
divided between the non-secure and secure states. OS like Linux kernel
in the non-secure state typically do not have SGIs to spare. The usage
of SGIs in the secure state is however limited. It is more likely that
software in the Secure world does not use all the SGIs allocated to it.
It is recommended that the secure world software donates an unused SGI
to the normal world for use as the schedule receiver interrupt. This
implies that secure world software must configure the SGI in the GIC
as a non-secure interrupt before presenting it to the normal world.
Link: https://lore.kernel.org/r/20231005-ffa_v1-1_notif-v4-8-cddd3237809c@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The receiver’s scheduler uses the FFA_NOTIFICATION_INFO_GET interface
to retrieve the list of endpoints that have pending notifications and
must be run. A notification could be signaled by a sender in the secure
world to a VM. The Hypervisor needs to determine which VM and vCPU
(in case a per-vCPU notification is signaled) has a pending notification
in this scenario. It must obtain this information through an invocation
of the FFA_NOTIFICATION_INFO_GET.
Add the implementation of the NOTIFICATION_INFO_GET interface
and prepare to use this to handle the schedule receiver interrupt.
Implementation of handling notifications will be added later.
Link: https://lore.kernel.org/r/20231005-ffa_v1-1_notif-v4-7-cddd3237809c@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The framework provides an interface to the receiver to determine the
identity of the notification. A receiver endpoint must use the
FFA_NOTIFICATION_GET interface to retrieve its pending notifications
and handle them.
Add the support for FFA_NOTIFICATION_GET to allow the caller(receiver)
to fetch its pending notifications from other partitions in the system.
Link: https://lore.kernel.org/r/20231005-ffa_v1-1_notif-v4-6-cddd3237809c@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The framework provides an interface to the sender to specify the
notification to signal to the receiver. A sender signals a notification
by requesting its partition manager to set the corresponding bit in the
notifications bitmap of the receiver invoking FFA_NOTIFICATION_SET.
Implement the FFA_NOTIFICATION_SET to enable the caller(sender) to send
the notifications for any other partitions in the system.
Link: https://lore.kernel.org/r/20231005-ffa_v1-1_notif-v4-5-cddd3237809c@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
FFA_RUN is used by a scheduler to allocate CPU cycles to a target
endpoint execution context specified in the target information parameter.
If the endpoint execution context is in the waiting/blocked state, it
transitions to the running state.
Expose the ability to call FFA_RUN in order to give any partition in the
system cpu cycles to perform IMPDEF functionality.
Link: https://lore.kernel.org/r/20231005-ffa_v1-1_notif-v4-4-cddd3237809c@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
A receiver endpoint must bind a notification to any sender endpoint
before the latter can signal the notification to the former. The receiver
assigns one or more doorbells to a specific sender. Only the sender can
ring these doorbells.
A receiver uses the FFA_NOTIFICATION_BIND interface to bind one or more
notifications to the sender. A receiver un-binds a notification from a
sender endpoint to stop the notification from being signaled. It uses
the FFA_NOTIFICATION_UNBIND interface to do this.
Allow the FF-A driver to be able to bind and unbind a given notification
ID to a specific partition ID. This will be used to register and
unregister notification callbacks from the FF-A client drivers.
Link: https://lore.kernel.org/r/20231005-ffa_v1-1_notif-v4-3-cddd3237809c@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
On systems without a hypervisor the responsibility of requesting the
creation of the notification bitmaps in the SPM falls to the FF-A driver.
We use FFA features to determine if the ABI is supported, if it is not
we can assume there is a hypervisor present and will take care of ensure
the relevant notifications bitmaps are created on this partitions behalf.
An endpoint’s notification bitmaps needs to be setup before it configures
its notifications and before other endpoints and partition managers can
start signaling these notifications.
Add interface to create and destroy the notification bitmaps and use the
same to do the necessary setup during the initialisation and cleanup
during the module exit.
Link: https://lore.kernel.org/r/20231005-ffa_v1-1_notif-v4-2-cddd3237809c@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Arm Firmware Framework for A-profile(FFA) v1.1 introduces notifications
and indirect messaging based upon notifications support and extends some
of the memory interfaces.
Let us add all the newly supported FF-A function IDs in the spec.
Also update to the error values and associated handling.
Link: https://lore.kernel.org/r/20231005-ffa_v1-1_notif-v4-1-cddd3237809c@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
In order to enable libkmod lookups for FF-A device objects to their
corresponding module, add 'modalias' to the base attribute of FF-A
devices.
Tested-by: Abdellatif El Khlifi <abdellatif.elkhlifi@arm.com>
Link: https://lore.kernel.org/r/20231005175640.379631-1-sudeep.holla@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
An FF-A ABI could support both the SMC32 and SMC64 conventions.
A callee that runs in the AArch64 execution state and implements such
an ABI must implement both SMC32 and SMC64 conventions of the ABI.
So the FF-A drivers will need the option to choose the mode irrespective
of FF-A version and the partition execution mode flag in the partition
information.
Let us remove the check on the FF-A version for allowing the selection
of 32bit mode of messaging. The driver will continue to set the 32-bit
mode if the partition execution mode flag specified that the partition
supports only 32-bit execution.
Fixes: 106b11b1cc ("firmware: arm_ffa: Set up 32bit execution mode flag using partiion property")
Link: https://lore.kernel.org/r/20231005142823.278121-1-sudeep.holla@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Commit 19b8766459 ("firmware: arm_ffa: Fix FFA device names for logical
partitions") added an ID to the FFA device using ida_alloc() and append
the same to "arm-ffa" to make up a unique device name. However it missed
to stash the id value in ffa_dev to help freeing the ID later when the
device is destroyed.
Due to the missing/unassigned ID in FFA device, we get the following
warning when the FF-A device is unregistered.
| ida_free called for id=0 which is not allocated.
| WARNING: CPU: 7 PID: 1 at lib/idr.c:525 ida_free+0x114/0x164
| CPU: 7 PID: 1 Comm: swapper/0 Not tainted 6.6.0-rc4 #209
| pstate: 61400009 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
| pc : ida_free+0x114/0x164
| lr : ida_free+0x114/0x164
| Call trace:
| ida_free+0x114/0x164
| ffa_release_device+0x24/0x3c
| device_release+0x34/0x8c
| kobject_put+0x94/0xf8
| put_device+0x18/0x24
| klist_devices_put+0x14/0x20
| klist_next+0xc8/0x114
| bus_for_each_dev+0xd8/0x144
| arm_ffa_bus_exit+0x30/0x54
| ffa_init+0x68/0x330
| do_one_initcall+0xdc/0x250
| do_initcall_level+0x8c/0xac
| do_initcalls+0x54/0x94
| do_basic_setup+0x1c/0x28
| kernel_init_freeable+0x104/0x170
| kernel_init+0x20/0x1a0
| ret_from_fork+0x10/0x20
Fix the same by actually assigning the ID in the FFA device this time
for real.
Fixes: 19b8766459 ("firmware: arm_ffa: Fix FFA device names for logical partitions")
Link: https://lore.kernel.org/r/20231003085932.3553985-1-sudeep.holla@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
As per the FF-A specification: section "Usage of other memory region
attributes", in a transaction to donate memory or lend memory to a single
borrower, if the receiver is a PE or Proxy endpoint, the owner must not
specify the attributes and the relayer will return INVALID_PARAMETERS
if the attributes are set.
Let us not set the memory region attributes for MEM_LEND.
Fixes: 82a8daaecf ("firmware: arm_ffa: Add support for MEM_LEND")
Reported-by: Joao Alves <joao.alves@arm.com>
Reported-by: Olivier Deprez <olivier.deprez@arm.com>
Link: https://lore.kernel.org/r/20230919-ffa_v1-1_notif-v2-13-6f3a3ca3923c@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
As described in the commit 111a833dc5 ("firmware: arm_ffa: Set
reserved/MBZ fields to zero in the memory descriptors") some fields in
the memory descriptor have to be zeroed explicitly. The handle field is
one of these, but it was left out from that change, fix this now.
Fixes: 111a833dc5 ("firmware: arm_ffa: Set reserved/MBZ fields to zero in the memory descriptors")
Reported-by: Imre Kis <imre.kis@arm.com>
Signed-off-by: Balint Dobszay <balint.dobszay@arm.com>
Link: https://lore.kernel.org/r/20230601140749.93812-1-balint.dobszay@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The transmit buffers allocated by the driver can be used to transmit data
by any messages/commands needing the buffer. However, it is not guaranteed
to have been zero-ed before every new transmission and hence it will just
contain residual value from the previous transmission. There are several
reserved fields in the memory descriptors that must be zero(MBZ). The
receiver can reject the transmission if any such MBZ fields are non-zero.
While we can set the whole page to zero, it is not optimal as most of the
fields get initialised to the value required for the current transmission.
So, just set the reserved/MBZ fields to zero in the memory descriptors
explicitly to honour the requirement and keep the receiver happy.
Fixes: cc2195fe53 ("firmware: arm_ffa: Add support for MEM_* interfaces")
Reported-by: Marc Bonnici <marc.bonnici@arm.com>
Link: https://lore.kernel.org/r/20230503131252.12585-1-sudeep.holla@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Each physical partition can provide multiple services each with UUID.
Each such service can be presented as logical partition with a unique
combination of VM ID and UUID. The number of distinct UUID in a system
will be less than or equal to the number of logical partitions.
However, currently it fails to register more than one logical partition
or service within a physical partition as the device name contains only
VM ID while both VM ID and UUID are maintained in the partition information.
The kernel complains with the below message:
| sysfs: cannot create duplicate filename '/devices/arm-ffa-8001'
| CPU: 1 PID: 1 Comm: swapper/0 Not tainted 6.3.0-rc7 #8
| Hardware name: FVP Base RevC (DT)
| Call trace:
| dump_backtrace+0xf8/0x118
| show_stack+0x18/0x24
| dump_stack_lvl+0x50/0x68
| dump_stack+0x18/0x24
| sysfs_create_dir_ns+0xe0/0x13c
| kobject_add_internal+0x220/0x3d4
| kobject_add+0x94/0x100
| device_add+0x144/0x5d8
| device_register+0x20/0x30
| ffa_device_register+0x88/0xd8
| ffa_setup_partitions+0x108/0x1b8
| ffa_init+0x2ec/0x3a4
| do_one_initcall+0xcc/0x240
| do_initcall_level+0x8c/0xac
| do_initcalls+0x54/0x94
| do_basic_setup+0x1c/0x28
| kernel_init_freeable+0x100/0x16c
| kernel_init+0x20/0x1a0
| ret_from_fork+0x10/0x20
| kobject_add_internal failed for arm-ffa-8001 with -EEXIST, don't try to
| register things with the same name in the same directory.
| arm_ffa arm-ffa: unable to register device arm-ffa-8001 err=-17
| ARM FF-A: ffa_setup_partitions: failed to register partition ID 0x8001
By virtue of being random enough to avoid collisions when generated in a
distributed system, there is no way to compress UUID keys to the number
of bits required to identify each. We can eliminate '-' in the name but
it is not worth eliminating 4 bytes and add unnecessary logic for doing
that. Also v1.0 doesn't provide the UUID of the partitions which makes
it hard to use the same for the device name.
So to keep it simple, let us alloc an ID using ida_alloc() and append the
same to "arm-ffa" to make up a unique device name. Also stash the id value
in ffa_dev to help freeing the ID later when the device is destroyed.
Fixes: e781858488 ("firmware: arm_ffa: Add initial FFA bus support for device enumeration")
Reported-by: Lucian Paul-Trifu <lucian.paul-trifu@arm.com>
Link: https://lore.kernel.org/r/20230419-ffa_fixes_6-4-v2-3-d9108e43a176@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Commit bb1be74985 ("firmware: arm_ffa: Add v1.1 get_partition_info support")
adds support to discovery the UUIDs of the partitions or just fetch the
partition count using the PARTITION_INFO_GET_RETURN_COUNT_ONLY flag.
However the commit doesn't handle the fact that the older version doesn't
understand the flag and must be MBZ which results in firmware returning
invalid parameter error. That results in the failure of the driver probe
which is in correct.
Limit the usage of the PARTITION_INFO_GET_RETURN_COUNT_ONLY flag for the
versions above v1.0(i.e v1.1 and onwards) which fixes the issue.
Fixes: bb1be74985 ("firmware: arm_ffa: Add v1.1 get_partition_info support")
Reported-by: Jens Wiklander <jens.wiklander@linaro.org>
Reported-by: Marc Bonnici <marc.bonnici@arm.com>
Tested-by: Jens Wiklander <jens.wiklander@linaro.org>
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Link: https://lore.kernel.org/r/20230419-ffa_fixes_6-4-v2-2-d9108e43a176@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Currently ffa_drv->remove() is called unconditionally from
ffa_device_remove(). Since the driver registration doesn't check for it
and allows it to be registered without .remove callback, we need to check
for the presence of it before executing it from ffa_device_remove() to
above a NULL pointer dereference like the one below:
| Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
| Mem abort info:
| ESR = 0x0000000086000004
| EC = 0x21: IABT (current EL), IL = 32 bits
| SET = 0, FnV = 0
| EA = 0, S1PTW = 0
| FSC = 0x04: level 0 translation fault
| user pgtable: 4k pages, 48-bit VAs, pgdp=0000000881cc8000
| [0000000000000000] pgd=0000000000000000, p4d=0000000000000000
| Internal error: Oops: 0000000086000004 [#1] PREEMPT SMP
| CPU: 3 PID: 130 Comm: rmmod Not tainted 6.3.0-rc7 #6
| Hardware name: FVP Base RevC (DT)
| pstate: 63402809 (nZCv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=-c)
| pc : 0x0
| lr : ffa_device_remove+0x20/0x2c
| Call trace:
| 0x0
| device_release_driver_internal+0x16c/0x260
| driver_detach+0x90/0xd0
| bus_remove_driver+0xdc/0x11c
| driver_unregister+0x30/0x54
| ffa_driver_unregister+0x14/0x20
| cleanup_module+0x18/0xeec
| __arm64_sys_delete_module+0x234/0x378
| invoke_syscall+0x40/0x108
| el0_svc_common+0xb4/0xf0
| do_el0_svc+0x30/0xa4
| el0_svc+0x2c/0x7c
| el0t_64_sync_handler+0x84/0xf0
| el0t_64_sync+0x190/0x194
Fixes: 244f5d597e ("firmware: arm_ffa: Add missing remove callback to ffa_bus_type")
Link: https://lore.kernel.org/r/20230419-ffa_fixes_6-4-v2-1-d9108e43a176@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The uevent() callback in struct bus_type should not be modifying the
device that is passed into it, so mark it as a const * and propagate the
function signature changes out into all relevant subsystems that use
this callback.
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230111113018.459199-16-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
FF-A function IDs and error codes will be needed in the hypervisor too,
so move to them to the header file where they can be shared. Rename the
version constants with an "FFA_" prefix so that they are less likely
to clash with other code in the tree.
Co-developed-by: Andrew Walbran <qwandor@google.com>
Signed-off-by: Andrew Walbran <qwandor@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/20221116170335.2341003-2-qperret@google.com
Signed-off-by: Will Deacon <will@kernel.org>
In preparation to make memory operations accessible for a non
ffa_driver/device, it is better to split the ffa_ops into different
categories of operations: info, message and memory. The info and memory
are ffa_device independent and can be used without any associated
ffa_device from a non ffa_driver.
However, we don't export these info and memory APIs yet without the user.
The first users of these APIs can export them.
Link: https://lore.kernel.org/r/20220907145240.1683088-11-sudeep.holla@arm.com
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
FF-A v1.1 adds a flag in the partition properties to indicate if the
partition runs in the AArch32 or AArch64 execution state. Use the same
to set-up the 32-bit execution flag mode in the ffa_dev automatically
if the detected firmware version is above v1.0 and ignore any requests
to do the same from the ffa_driver.
Link: https://lore.kernel.org/r/20220907145240.1683088-10-sudeep.holla@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
FF-A v1.1 adds support to discovery the UUIDs of the partitions that was
missing in v1.0 and which the driver workarounds by using UUIDs supplied
by the ffa_drivers.
Add the v1.1 get_partition_info support and disable the workaround if
the detected FF-A version is greater than v1.0.
Link: https://lore.kernel.org/r/20220907145240.1683088-9-sudeep.holla@arm.com
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Except the message APIs, all other APIs are ffa_device independent and can
be used without any associated ffa_device from a non ffa_driver.
In order to reflect the same, just rename ffa_dev_ops as ffa_ops to
avoid any confusion or to keep it simple.
Link: https://lore.kernel.org/r/20220907145240.1683088-8-sudeep.holla@arm.com
Suggested-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
There is a requirement to make memory APIs independent of the ffa_device.
One of the use-case is to have a common memory driver that manages the
memory for all the ffa_devices. That common memory driver won't be a
ffa_driver or won't have any ffa_device associated with it. So having
these memory APIs accessible without a ffa_device is needed and should
be possible as most of these are handled by the partition manager(SPM
or hypervisor).
Drop the ffa_device argument to the memory APIs and make them ffa_device
independent.
Link: https://lore.kernel.org/r/20220907145240.1683088-7-sudeep.holla@arm.com
Acked-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Currently, the ffa_dev->mode_32bit is use to detect if the native 64-bit
or 32-bit versions of FF-A ABI needs to be used. However for the FF-A
memory ABIs, it is not dependent on the ffa_device(i.e. the partition)
itself, but the partition manager(SPM).
So, the FFA_FEATURES can be use to detect if the native 64bit ABIs are
supported or not and appropriate calls can be made based on that.
Use FFA_FEATURES to detect if native versions of MEM_LEND or MEM_SHARE
are implemented and make of the same to use native memory ABIs later on.
Link: https://lore.kernel.org/r/20220907145240.1683088-6-sudeep.holla@arm.com
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Add support for FFA_FEATURES to discover properties supported at the
FF-A interface. This interface can be used to query:
- If an FF-A interface is implemented by the component at the higher EL,
- If an implemented FF-A interface also implements any optional features
described in its interface definition, and
- Any implementation details exported by an implemented FF-A interface
as described in its interface definition.
Link: https://lore.kernel.org/r/20220907145240.1683088-5-sudeep.holla@arm.com
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The only user of this exported ffa_dev_ops_get() was OPTEE driver which
now uses ffa_dev->ops directly, there are no other users for this.
Also, since any ffa driver can use ffa_dev->ops directly, there will be
no need for ffa_dev_ops_get(), so just remove ffa_dev_ops_get().
Link: https://lore.kernel.org/r/20220907145240.1683088-4-sudeep.holla@arm.com
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Currently ffa_dev_ops_get() is the way to fetch the ffa_dev_ops pointer.
It checks if the ffa_dev structure pointer is valid before returning the
ffa_dev_ops pointer.
Instead, the pointer can be made part of the ffa_dev structure and since
the core driver is incharge of creating ffa_device for each identified
partition, there is no need to check for the validity explicitly if the
pointer is embedded in the structure.
Add the pointer to the ffa_dev_ops in the ffa_dev structure itself and
initialise the same as part of creation of the device.
Link: https://lore.kernel.org/r/20220907145240.1683088-2-sudeep.holla@arm.com
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The ffa core driver currently assigns its own driver information
to individual ffa device driver_data which is wrong. Firstly, it leaks
this core driver information to individual ffa_device and hence to
ffa_driver. Secondly the ffa_device driver_data is for use by individual
ffa_driver and not for this core driver managing all those devices.
Link: https://lore.kernel.org/r/20220429113946.2087145-2-sudeep.holla@arm.com
Fixes: d0c0bce831 ("firmware: arm_ffa: Setup in-kernel users of FFA partitions")
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
While we pass uuid_null intentionally to ffa_partition_probe in
ffa_setup_partitions to get the count of the partitions, it must not be
uuid_null in ffa_partition_info_get which is used by the ffa_drivers
to fetch the specific partition info passing the UUID of the partition.
Fix ffa_partition_info_get by passing the received uuid down to
ffa_partition_probe so that the correct partition information is fetched.
Link: https://lore.kernel.org/r/20220429113946.2087145-1-sudeep.holla@arm.com
Fixes: d0c0bce831 ("firmware: arm_ffa: Setup in-kernel users of FFA partitions")
Reported-by: Arunachalam Ganapathy <arunachalam.ganapathy@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Fix the handling of MEM_FRAG_TX/RX SMCs when the full memory descriptor
does not fit in a single innovation of a memory sharing request.
The current implementation expects a FFA_MEM_SHARE/FFA_MEM_LEND
call to always receive a FFA_SUCCESS response, however in the
case where a full descriptor does not fit inside the partitions
TX buffer, the call can instead complete with a FFA_MEM_FRAG_RX SMC
to request the next part of the descriptor to be transmitted.
Similarly a FFA_MEM_FRAG_TX call currently only expects
FFA_MEM_FRAG_RX as a response, however once the full descriptor
has been transmitted the FFA_SUCCESS ABI will be used to indicate
successful transmission.
Update the existing code to match the expected behaviour.
Link: https://lore.kernel.org/r/20220426121219.1801601-1-marc.bonnici@arm.com
Signed-off-by: Marc Bonnici <marc.bonnici@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The newly added ffa_compatible_version_find() function causes a
build warning because of a variable that is never used:
drivers/firmware/arm_ffa/driver.c:180:6: error: unused variable 'compat_version' [-Werror,-Wunused-variable]
u32 compat_version;
Link: https://lore.kernel.org/r/20211026083400.3444946-1-arnd@kernel.org
Fixes: 8e3f9da608 ("firmware: arm_ffa: Handle compatibility with different firmware versions")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
As part of the FF-A spec, an endpoint is allowed to transfer access of,
or lend, a memory region to one or more borrowers.
Extend the existing memory sharing implementation to support
FF-A MEM_LEND functionality and expose this to other kernel drivers.
Note that upon a successful MEM_LEND request the caller must ensure that
the memory region specified is not accessed until a successful
MEM_RECALIM call has been made. On systems with a hypervisor present
this will been enforced, however on systems without a hypervisor the
responsibility falls to the calling kernel driver to prevent access.
Link: https://lore.kernel.org/r/20211015165742.2513065-1-marc.bonnici@arm.com
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Marc Bonnici <marc.bonnici@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The driver currently just support v1.0 of Arm FFA specification. It also
expects the firmware implementation to match the same and bail out if it
doesn't match. This is causing issue when running with higher version of
firmware implementation(e.g. v1.1 which will released soon).
In order to support compatibility with different firmware versions, let
us add additional checks and find the compatible version the driver can
work with.
Link: https://lore.kernel.org/r/20211013091127.990992-1-sudeep.holla@arm.com
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
When arm_ffa firmware driver module is unloaded or removed we call
__ffa_devices_unregister on all the devices on the ffa bus. It must
unregister all the devices instead it is currently just releasing the
devices without unregistering. That is pure wrong as when we try to
load the module back again, it will result in the kernel crash something
like below.
-->8
CPU: 2 PID: 232 Comm: modprobe Not tainted 5.15.0-rc2+ #169
Hardware name: FVP Base RevC (DT)
Call trace:
dump_backtrace+0x0/0x1cc
show_stack+0x18/0x64
dump_stack_lvl+0x64/0x7c
dump_stack+0x18/0x38
sysfs_create_dir_ns+0xe4/0x140
kobject_add_internal+0x170/0x358
kobject_add+0x94/0x100
device_add+0x178/0x5f0
device_register+0x20/0x30
ffa_device_register+0x80/0xcc [ffa_module]
ffa_setup_partitions+0x7c/0x108 [ffa_module]
init_module+0x290/0x2dc [ffa_module]
do_one_initcall+0xbc/0x230
do_init_module+0x58/0x304
load_module+0x15e0/0x1f68
__arm64_sys_finit_module+0xb8/0xf4
invoke_syscall+0x44/0x140
el0_svc_common+0xb4/0xf0
do_el0_svc+0x24/0x80
el0_svc+0x20/0x50
el0t_64_sync_handler+0x84/0xe4
el0t_64_sync+0x1a0/0x1a4
kobject_add_internal failed for arm-ffa-8001 with -EEXIST, don't try to
register things with the same name in the same directory.
----
Fix the issue by calling device_unregister in __ffa_devices_unregister
which will also take care of calling device_release(which is mapped to
ffa_release_device)
Link: https://lore.kernel.org/r/20210924092859.3057562-2-sudeep.holla@arm.com
Fixes: e781858488 ("firmware: arm_ffa: Add initial FFA bus support for device enumeration")
Tested-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Currently the arm_ffa firmware driver can be built as module and hence
all the users of FFA driver. If any driver on the ffa bus is removed or
unregistered, the remove callback on all the device bound to the driver
being removed should be callback. For that to happen, we must register
a remove callback on the ffa_bus which is currently missing. This results
in the probe getting called again without the previous remove callback
on a device which may result in kernel crash.
Fix the issue by registering the remove callback on the FFA bus.
Link: https://lore.kernel.org/r/20210924092859.3057562-1-sudeep.holla@arm.com
Fixes: e781858488 ("firmware: arm_ffa: Add initial FFA bus support for device enumeration")
Reported-by: Jens Wiklander <jens.wiklander@linaro.org>
Tested-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The ffa_linux_errmap buffer access index is supposed to range from 0-8
but it ranges from 1-9 instead. It reads one element out of bounds. It
also changes the success into -EINVAL though ffa_to_linux_errno 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/20210707134739.1869481-1-sudeep.holla@arm.com
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
clang produces the following warning:
drivers/firmware/arm_ffa/driver.c:123: warning: expecting
prototype for FF(). Prototype was for FFA_PAGE_SIZE() instead
This comment starts with '/**', but isn't a kernel-doc comment.
Refer Documentation/doc-guide/kernel-doc.rst
Fix the same by removing the kernel-doc style comment here.
Link: https://lore.kernel.org/r/20210622162202.3485866-1-sudeep.holla@arm.com
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
When the driver core calls the probe callback it already checked that
the devices match, so there is no need to call the match callback again.
Link: https://lore.kernel.org/r/20210621201652.127611-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
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/20210621201652.127611-1-u.kleine-koenig@pengutronix.de
Fixes: e781858488 ("firmware: arm_ffa: Add initial FFA bus support for device enumeration")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Most of the MEM_* APIs share the same parameters, so they can be
generalised. Currently only MEM_SHARE is implemented and the user space
interface for that is not added yet.
Link: https://lore.kernel.org/r/20210521151033.181846-6-sudeep.holla@arm.com
Tested-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Parse the FFA nodes from the device-tree and register all the partitions
whose services will be used in the kernel.
In order to also enable in-kernel users of FFA interface, let us add
simple set of operations for such devices.
The in-kernel users are registered without the character device interface.
Link: https://lore.kernel.org/r/20210521151033.181846-5-sudeep.holla@arm.com
Tested-by: Jens Wiklander <jens.wiklander@linaro.org>
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
There are requests to keep the transport separate in order to allow
other possible transports like virtio. So let us keep the SMCCC transport
specific routines abstracted.
It is kept simple for now. Once we add another transport, we can develop
better abstraction.
Link: https://lore.kernel.org/r/20210521151033.181846-4-sudeep.holla@arm.com
Tested-by: Jens Wiklander <jens.wiklander@linaro.org>
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
This just add a basic driver that sets up the transport(e.g. SMCCC),
checks the FFA version implemented, get the partition ID for self and
sets up the Tx/Rx buffers for communication.
Link: https://lore.kernel.org/r/20210521151033.181846-3-sudeep.holla@arm.com
Tested-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The Arm FF for Armv8-A specification has concept of endpoints or
partitions. In the Normal world, a partition could be a VM when
the Virtualization extension is enabled or the kernel itself.
In order to handle multiple partitions, we can create a FFA device for
each such partition on a dedicated FFA bus. Similarly, different drivers
requiring FFA transport can be registered on the same bus. We can match
the device and drivers using UUID. This is mostly for the in-kernel
users with FFA drivers.
Link: https://lore.kernel.org/r/20210521151033.181846-2-sudeep.holla@arm.com
Tested-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
