1. 14 Jun, 2018 1 commit
    • Roberto Vargas's avatar
      Make TF UUID RFC 4122 compliant · 03364865
      Roberto Vargas authored
      
      
      RFC4122 defines that fields are stored in network order (big endian),
      but TF-A stores them in machine order (little endian by default in TF-A).
      We cannot change the future UUIDs that are already generated, but we can store
      all the bytes using arrays and modify fiptool to generate the UUIDs with
      the correct byte order.
      
      Change-Id: I97be2d3168d91f4dee7ccfafc533ea55ff33e46f
      Signed-off-by: default avatarRoberto Vargas <roberto.vargas@arm.com>
      03364865
  2. 27 Apr, 2018 1 commit
  3. 21 Apr, 2018 1 commit
  4. 26 Mar, 2018 1 commit
  5. 27 Feb, 2018 1 commit
  6. 06 Feb, 2018 1 commit
  7. 12 Jul, 2017 1 commit
    • Isla Mitchell's avatar
      Fix order of #includes · 2a4b4b71
      Isla Mitchell authored
      
      
      This fix modifies the order of system includes to meet the ARM TF coding
      standard. There are some exceptions in order to retain header groupings,
      minimise changes to imported headers, and where there are headers within
      the #if and #ifndef statements.
      
      Change-Id: I65085a142ba6a83792b26efb47df1329153f1624
      Signed-off-by: default avatarIsla Mitchell <isla.mitchell@arm.com>
      2a4b4b71
  8. 03 May, 2017 1 commit
  9. 26 Apr, 2017 1 commit
  10. 20 Apr, 2017 1 commit
    • Antonio Nino Diaz's avatar
      tspd:FWU:Fix usage of SMC_RET0 · 7a317a70
      Antonio Nino Diaz authored
      
      
      SMC_RET0 should only be used when the SMC code works as a function that
      returns void. If the code of the SMC uses SMC_RET1 to return a value to
      signify success and doesn't return anything in case of an error (or the
      other way around) SMC_RET1 should always be used to return clearly
      identifiable values.
      
      This patch fixes two cases in which the code used SMC_RET0 instead of
      SMC_RET1.
      
      It also introduces the define SMC_OK to use when an SMC must return a
      value to tell that it succeeded, the same way as SMC_UNK is used in case
      of failure.
      
      Change-Id: Ie4278b51559e4262aced13bbde4e844023270582
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      7a317a70
  11. 23 Feb, 2017 1 commit
    • Douglas Raillard's avatar
      Fix TSPD implementation of STD SMC ABORT · 57a5a56c
      Douglas Raillard authored
      
      
      ABORT SMC used to return to the previously executing world, which
      happened to be S-EL1 as it calls a TSP handler using synchronous entry
      into the TSP.
      
      Now properly save and restore the non-secure context (including system
      registers) and return to non-secure world as it should.
      
      fixes ARM-Software/tf-issues#453
      
      Change-Id: Ie40c79ca2636ab8b6b2ab3106e8f49e0f9117f5f
      Signed-off-by: default avatarDouglas Raillard <douglas.raillard@arm.com>
      57a5a56c
  12. 23 Dec, 2016 1 commit
    • Douglas Raillard's avatar
      Abort preempted TSP STD SMC after PSCI CPU suspend · 3df6012a
      Douglas Raillard authored
      
      
      Standard SMC requests that are handled in the secure-world by the Secure
      Payload can be preempted by interrupts that must be handled in the
      normal world. When the TSP is preempted the secure context is stored and
      control is passed to the normal world to handle the non-secure
      interrupt. Once completed the preempted secure context is restored. When
      restoring the preempted context, the dispatcher assumes that the TSP
      preempted context is still stored as the SECURE context by the context
      management library.
      
      However, PSCI power management operations causes synchronous entry into
      TSP. This overwrites the preempted SECURE context in the context
      management library. When restoring back the SECURE context, the Secure
      Payload crashes because this context is not the preempted context
      anymore.
      
      This patch avoids corruption of the preempted SECURE context by aborting
      any preempted SMC during PSCI power management calls. The
      abort_std_smc_entry hook of the TSP is called when aborting the SMC
      request.
      
      It also exposes this feature as a FAST SMC callable from normal world to
      abort preempted SMC with FID TSP_FID_ABORT.
      
      Change-Id: I7a70347e9293f47d87b5de20484b4ffefb56b770
      Signed-off-by: default avatarDouglas Raillard <douglas.raillard@arm.com>
      3df6012a
  13. 21 Dec, 2015 1 commit
  14. 09 Dec, 2015 1 commit
    • Soby Mathew's avatar
      TSP: Allow preemption of synchronous S-EL1 interrupt handling · 63b8440f
      Soby Mathew authored
      Earlier the TSP only ever expected to be preempted during Standard SMC
      processing. If a S-EL1 interrupt triggered while in the normal world, it
      will routed to S-EL1 `synchronously` for handling. The `synchronous` S-EL1
      interrupt handler `tsp_sel1_intr_entry` used to panic if this S-EL1 interrupt
      was preempted by another higher priority pending interrupt which should be
      handled in EL3 e.g. Group0 interrupt in GICv3.
      
      With this patch, the `tsp_sel1_intr_entry` now expects `TSP_PREEMPTED` as the
      return code from the `tsp_common_int_handler` in addition to 0 (interrupt
      successfully handled) and in both cases it issues an SMC with id
      `TSP_HANDLED_S_EL1_INTR`. The TSPD switches the context and returns back
      to normal world. In case a higher priority EL3 interrupt was pending, the
      execution will be routed to EL3 where interrupt will be handled. On return
      back to normal world, the pending S-EL1 interrupt which was preempted will
      get routed to S-EL1 to be handled `synchronously` via `tsp_sel1_intr_entry`.
      
      Change-Id: I2087c7fedb37746fbd9200cdda9b6dba93e16201
      63b8440f
  15. 04 Dec, 2015 2 commits
    • Soby Mathew's avatar
      Enable use of FIQs and IRQs as TSP interrupts · 02446137
      Soby Mathew authored
      On a GICv2 system, interrupts that should be handled in the secure world are
      typically signalled as FIQs. On a GICv3 system, these interrupts are signalled
      as IRQs instead. The mechanism for handling both types of interrupts is the same
      in both cases. This patch enables the TSP to run on a GICv3 system by:
      
      1. adding support for handling IRQs in the exception handling code.
      2. removing use of "fiq" in the names of data structures, macros and functions.
      
      The build option TSPD_ROUTE_IRQ_TO_EL3 is deprecated and is replaced with a
      new build flag TSP_NS_INTR_ASYNC_PREEMPT. For compatibility reasons, if the
      former build flag is defined, it will be used to define the value for the
      new build flag. The documentation is also updated accordingly.
      
      Change-Id: I1807d371f41c3656322dd259340a57649833065e
      02446137
    • Soby Mathew's avatar
      Unify interrupt return paths from TSP into the TSPD · 404dba53
      Soby Mathew authored
      The TSP is expected to pass control back to EL3 if it gets preempted due to
      an interrupt while handling a Standard SMC in the following scenarios:
      
      1. An FIQ preempts Standard SMC execution and that FIQ is not a TSP Secure
         timer interrupt or is preempted by a higher priority interrupt by the time
         the TSP acknowledges it. In this case, the TSP issues an SMC with the ID
         as `TSP_EL3_FIQ`. Currently this case is never expected to happen as only
         the TSP Secure Timer is expected to generate FIQ.
      
      2. An IRQ preempts Standard SMC execution and in this case the TSP issues
         an SMC with the ID as `TSP_PREEMPTED`.
      
      In both the cases, the TSPD hands control back to the normal world and returns
      returns an error code to the normal world to indicate that the standard SMC it
      had issued has been preempted but not completed.
      
      This patch unifies the handling of these two cases in the TSPD and ensures that
      the TSP only uses TSP_PREEMPTED instead of separate SMC IDs. Also instead of 2
      separate error codes, SMC_PREEMPTED and TSP_EL3_FIQ, only SMC_PREEMPTED is
      returned as error code back to the normal world.
      
      Background information: On a GICv3 system, when the secure world has affinity
      routing enabled, in 2. an FIQ will preempt TSP execution instead of an IRQ. The
      FIQ could be a result of a Group 0 or a Group 1 NS interrupt. In both case, the
      TSPD passes control back to the normal world upon receipt of the TSP_PREEMPTED
      SMC. A Group 0 interrupt will immediately preempt execution to EL3 where it
      will be handled. This allows for unified interrupt handling in TSP for both
      GICv3 and GICv2 systems.
      
      Change-Id: I9895344db74b188021e3f6a694701ad272fb40d4
      404dba53
  16. 26 Nov, 2015 1 commit
    • Soby Mathew's avatar
      Remove the IMF_READ_INTERRUPT_ID build option · 54718418
      Soby Mathew authored
      The IMF_READ_INTERRUPT_ID build option enables a feature where the interrupt
      ID of the highest priority pending interrupt is passed as a parameter to the
      interrupt handler registered for that type of interrupt. This additional read
      of highest pending interrupt id from GIC is problematic as it is possible that
      the original interrupt may get deasserted and another interrupt of different
      type maybe become the highest pending interrupt. Hence it is safer to prevent
      such behaviour by removing the IMF_READ_INTERRUPT_ID build option.
      
      The `id` parameter of the interrupt handler `interrupt_type_handler_t` is
      now made a reserved parameter with this patch. It will always contain
      INTR_ID_UNAVAILABLE.
      
      Fixes ARM-software/tf-issues#307
      
      Change-Id: I2173aae1dd37edad7ba6bdfb1a99868635fa34de
      54718418
  17. 13 Aug, 2015 1 commit
    • Soby Mathew's avatar
      PSCI: Migrate SPDs and TSP to the new platform and framework API · fd650ff6
      Soby Mathew authored
      The new PSCI frameworks mandates that the platform APIs and the various
      frameworks in Trusted Firmware migrate away from MPIDR based core
      identification to one based on core index. Deprecated versions of the old
      APIs are still present to provide compatibility but their implementations
      are not optimal. This patch migrates the various SPDs exisiting within
      Trusted Firmware tree and TSP to the new APIs.
      
      Change-Id: Ifc37e7071c5769b5ded21d0b6a071c8c4cab7836
      fd650ff6
  18. 26 Jan, 2015 1 commit
    • Soby Mathew's avatar
      Demonstrate model for routing IRQs to EL3 · f4f1ae77
      Soby Mathew authored
      This patch provides an option to specify a interrupt routing model
      where non-secure interrupts (IRQs) are routed to EL3 instead of S-EL1.
      When such an interrupt occurs, the TSPD arranges a return to
      the normal world after saving any necessary context. The interrupt
      routing model to route IRQs to EL3 is enabled only during STD SMC
      processing. Thus the pre-emption of S-EL1 is disabled during Fast SMC
      and Secure Interrupt processing.
      
      A new build option TSPD_ROUTE_NS_INT_EL3 is introduced to change
      the non secure interrupt target execution level to EL3.
      
      Fixes ARM-software/tf-issues#225
      
      Change-Id: Ia1e779fbbb6d627091e665c73fa6315637cfdd32
      f4f1ae77
  19. 19 Aug, 2014 1 commit
    • Juan Castillo's avatar
      Add support for PSCI SYSTEM_OFF and SYSTEM_RESET APIs · d5f13093
      Juan Castillo authored
      This patch adds support for SYSTEM_OFF and SYSTEM_RESET PSCI
      operations. A platform should export handlers to complete the
      requested operation. The FVP port exports fvp_system_off() and
      fvp_system_reset() as an example.
      
      If the SPD provides a power management hook for system off and
      system reset, then the SPD is notified about the corresponding
      operation so it can do some bookkeeping. The TSPD exports
      tspd_system_off() and tspd_system_reset() for that purpose.
      
      Versatile Express shutdown and reset methods have been removed
      from the FDT as new PSCI sys_poweroff and sys_reset services
      have been added. For those kernels that do not support yet these
      PSCI services (i.e. GICv3 kernel), the original dtsi files have
      been renamed to *-no_psci.dtsi.
      
      Fixes ARM-software/tf-issues#218
      
      Change-Id: Ic8a3bf801db979099ab7029162af041c4e8330c8
      d5f13093
  20. 01 Aug, 2014 2 commits
    • Vikram Kanigiri's avatar
      Support asynchronous method for BL3-2 initialization · faaa2e76
      Vikram Kanigiri authored
      This patch adds support for BL3-2 initialization by asynchronous
      method where BL3-1 transfers control to BL3-2 using world switch.
      After BL3-2 initialization, it transfers control to BL3-3 via SPD
      service handler. The SPD service handler initializes the CPU context
      to BL3-3 entrypoint depending on the return function indentifier from
      TSP initialization.
      
      Fixes ARM-software/TF-issues#184
      
      Change-Id: I7b135c2ceeb356d3bb5b6a287932e96ac67c7a34
      faaa2e76
    • Vikram Kanigiri's avatar
      Rework the TSPD setup code · 50e27dad
      Vikram Kanigiri authored
      There is no mechanism which allows the TSPD to specify what SPSR to
      use when entering BL3-2 instead of BL3-3. This patch divides the
      responsibility between tspd_setup() and tspd_init() for initializing
      the TSPD and TSP to support the alternate BL3-2 initialization flow
      where BL3-1 handsover control to BL3-2 instead of BL3-3.
      SPSR generated by TSPD for TSP is preserved due the new division of
      labour which fixes #174.
      
      This patch also moves the cpu_context initialization code from
      tspd_setup() to tspd_init() immediately before entering the TSP.
      Instead tspd_setup() updates the BL3-2 entrypoint info structure
      with the state required for initializing the TSP later.
      
      Fixes  ARM-software/TF-issues#174
      
      Change-Id: Ida0a8a48d466c71d5b07b8c7f2af169b73f96940
      50e27dad
  21. 23 Jun, 2014 1 commit
    • Andrew Thoelke's avatar
      Initialise CPU contexts from entry_point_info · 167a9357
      Andrew Thoelke authored
      Consolidate all BL3-1 CPU context initialization for cold boot, PSCI
      and SPDs into two functions:
      *  The first uses entry_point_info to initialize the relevant
         cpu_context for first entry into a lower exception level on a CPU
      *  The second populates the EL1 and EL2 system registers as needed
         from the cpu_context to ensure correct entry into the lower EL
      
      This patch alters the way that BL3-1 determines which exception level
      is used when first entering EL1 or EL2 during cold boot - this is now
      fully determined by the SPSR value in the entry_point_info for BL3-3,
      as set up by the platform code in BL2 (or otherwise provided to BL3-1).
      
      In the situation that EL1 (or svc mode) is selected for a processor
      that supports EL2, the context management code will now configure all
      essential EL2 register state to ensure correct execution of EL1. This
      allows the platform code to run non-secure EL1 payloads directly
      without requiring a small EL2 stub or OS loader.
      
      Change-Id: If9fbb2417e82d2226e47568203d5a369f39d3b0f
      167a9357
  22. 11 Jun, 2014 1 commit
    • Andrew Thoelke's avatar
      Provide cm_get/set_context() for current CPU · 08ab89d3
      Andrew Thoelke authored
      All callers of cm_get_context() pass the calling CPU MPIDR to the
      function. Providing a specialised version for the current
      CPU results in a reduction in code size and better readability.
      
      The current function has been renamed to cm_get_context_by_mpidr()
      and the existing name is now used for the current-CPU version.
      
      The same treatment has been done to cm_set_context(), although
      only both forms are used at present in the PSCI and TSPD code.
      
      Change-Id: I91cb0c2f7bfcb950a045dbd9ff7595751c0c0ffb
      08ab89d3
  23. 29 May, 2014 1 commit
  24. 27 May, 2014 2 commits
    • Dan Handley's avatar
      Further renames of platform porting functions · 9865ac15
      Dan Handley authored
      Rename the ic_* platform porting functions to plat_ic_* to be
      consistent with the other functions in platform.h. Also rename
      bl31_get_next_image_info() to bl31_plat_get_next_image_ep_info()
      and remove the duplicate declaration in bl31.h.
      
      Change-Id: I4851842069d3cff14c0a468daacc0a891a7ede84
      9865ac15
    • Soby Mathew's avatar
      Fixup Standard SMC Resume Handling · 10b65ecf
      Soby Mathew authored
      This patch fixes a missed return and code alignment issues
      in TSP_FID_RESUME handling.
      
      Change-Id: Icf8aeb76dfd6898745653ce039e3bac45e0a9b3a
      10b65ecf
  25. 23 May, 2014 2 commits
    • Andrew Thoelke's avatar
      Use a vector table for TSP entrypoints · 399fb08f
      Andrew Thoelke authored
      The TSP has a number of entrypoints used by the TSP on different
      occasions. These were provided to the TSPD as a table of function
      pointers, and required the TSPD to read the entry in the table,
      which is in TSP memory, in order to program the exception return
      address.
      
      Ideally, the TSPD has no access to the TSP memory.
      
      This patch changes the table of function pointers into a vector
      table of single instruction entrypoints. This allows the TSPD to
      calculate the entrypoint address instead of read it.
      
      Fixes ARM-software/tf-issues#160
      
      Change-Id: Iec6e055d537ade78a45799fbc6f43765a4725ad3
      399fb08f
    • Soby Mathew's avatar
      Non-Secure Interrupt support during Standard SMC processing in TSP · 239b04fa
      Soby Mathew authored
      Implements support for Non Secure Interrupts preempting the
      Standard SMC call in EL1. Whenever an IRQ is trapped in the
      Secure world we securely handover to the Normal world
      to process the interrupt. The normal world then issues
      "resume" smc call to resume the previous interrupted SMC call.
      Fixes ARM-software/tf-issues#105
      
      Change-Id: I72b760617dee27438754cdfc9fe9bcf4cc024858
      239b04fa
  26. 22 May, 2014 5 commits
    • Achin Gupta's avatar
      Add S-EL1 interrupt handling support in the TSPD · b44a4435
      Achin Gupta authored
      This patch adds support in the TSPD for registering a handler for
      S-EL1 interrupts. This handler ferries the interrupts generated in the
      non-secure state to the TSP at 'tsp_fiq_entry'. Support has been added
      to the smc handler to resume execution in the non-secure state once
      interrupt handling has been completed by the TSP.
      
      There is also support for resuming execution in the normal world if
      the TSP receives a EL3 interrupt. This code is currently unused.
      
      Change-Id: I816732595a2635e299572965179f11aa0bf93b69
      b44a4435
    • Achin Gupta's avatar
      Add context library API to change a bit in SCR_EL3 · c429b5e9
      Achin Gupta authored
      This patch adds an API to write to any bit in the SCR_EL3 member of
      the 'cpu_context' structure of the current CPU for a specified
      security state. This API will be used in subsequent patches which
      introduce interrupt management in EL3 to specify the interrupt routing
      model when execution is not in EL3.
      
      It also renames the cm_set_el3_elr() function to cm_set_elr_el3()
      which is more in line with the system register name being targeted by
      the API.
      
      Change-Id: I310fa7d8f827ad3f350325eca2fb28cb350a85ed
      c429b5e9
    • Achin Gupta's avatar
      Rework 'state' field usage in per-cpu TSP context · 3ee8a164
      Achin Gupta authored
      This patch lays the foundation for using the per-cpu 'state' field in
      the 'tsp_context' structure for other flags apart from the power state
      of the TSP.
      
      It allocates 2 bits for the power state, introduces the necessary
      macros to manipulate the power state in the 'state' field and
      accordingly reworks all use of the TSP_STATE_* states.
      
      It also allocates a flag bit to determine if the TSP is handling a
      standard SMC. If this flag is set then the TSP was interrupted due to
      non-secure or EL3 interupt depending upon the chosen routing
      model. Macros to get, set and clear this flag have been added as
      well. This flag will be used by subsequent patches.
      
      Change-Id: Ic6ee80bd5895812c83b35189cf2c3be70a9024a6
      3ee8a164
    • Vikram Kanigiri's avatar
      Rework memory information passing to BL3-x images · 6871c5d3
      Vikram Kanigiri authored
      The issues addressed in this patch are:
      
      1. Remove meminfo_t from the common interfaces in BL3-x,
      expecting that platform code will find a suitable mechanism
      to determine the memory extents in these images and provide
      it to the BL3-x images.
      
      2. Remove meminfo_t and bl31_plat_params_t from all FVP BL3-x
      code as the images use link-time information to determine
      memory extents.
      
      meminfo_t is still used by common interface in BL1/BL2 for
      loading images
      
      Change-Id: I4e825ebf6f515b59d84dc2bdddf6edbf15e2d60f
      6871c5d3
    • Vikram Kanigiri's avatar
      Populate BL31 input parameters as per new spec · 4112bfa0
      Vikram Kanigiri authored
      This patch is based on spec published at
      https://github.com/ARM-software/tf-issues/issues/133
      
      It rearranges the bl31_args struct into
      bl31_params and bl31_plat_params which provide the
      information needed for Trusted firmware and platform
      specific data via x0 and x1
      
      On the FVP platform BL3-1 params and BL3-1 plat params
      and its constituents are stored at the start of TZDRAM.
      
      The information about memory availability and size for
      BL3-1, BL3-2 and BL3-3 is moved into platform specific data.
      
      Change-Id: I8b32057a3d0dd3968ea26c2541a0714177820da9
      4112bfa0
  27. 06 May, 2014 3 commits
    • Dan Handley's avatar
      Reduce deep nesting of header files · 97043ac9
      Dan Handley authored
      Reduce the number of header files included from other header
      files as much as possible without splitting the files. Use forward
      declarations where possible. This allows removal of some unnecessary
      "#ifndef __ASSEMBLY__" statements.
      
      Also, review the .c and .S files for which header files really need
      including and reorder the #include statements alphabetically.
      
      Fixes ARM-software/tf-issues#31
      
      Change-Id: Iec92fb976334c77453e010b60bcf56f3be72bd3e
      97043ac9
    • Dan Handley's avatar
      Always use named structs in header files · fb037bfb
      Dan Handley authored
      Add tag names to all unnamed structs in header files. This
      allows forward declaration of structs, which is necessary to
      reduce header file nesting (to be implemented in a subsequent
      commit).
      
      Also change the typedef names across the codebase to use the _t
      suffix to be more conformant with the Linux coding style. The
      coding style actually prefers us not to use typedefs at all but
      this is considered a step too far for Trusted Firmware.
      
      Also change the IO framework structs defintions to use typedef'd
      structs to be consistent with the rest of the codebase.
      
      Change-Id: I722b2c86fc0d92e4da3b15e5cab20373dd26786f
      fb037bfb
    • Dan Handley's avatar
      Make use of user/system includes more consistent · 35e98e55
      Dan Handley authored
      Make codebase consistent in its use of #include "" syntax for
      user includes and #include <> syntax for system includes.
      
      Fixes ARM-software/tf-issues#65
      
      Change-Id: If2f7c4885173b1fd05ac2cde5f1c8a07000c7a33
      35e98e55
  28. 20 Mar, 2014 1 commit
    • Jeenu Viswambharan's avatar
      Implement standard calls for TSP · 52538b9b
      Jeenu Viswambharan authored
      This patch adds call count, UID and version information SMC calls for
      the Trusted OS, as specified by the SMC calling convention.
      
      Change-Id: I9a3e84ac1bb046051db975d853dcbe9612aba6a9
      52538b9b
  29. 26 Feb, 2014 1 commit
    • Jeenu Viswambharan's avatar
      Implement late binding for runtime hooks · 7f366605
      Jeenu Viswambharan authored
      At present SPD power management hooks and BL3-2 entry are implemented
      using weak references. This would have the handlers bound and registered
      with the core framework at build time, but leaves them dangling if a
      service fails to initialize at runtime.
      
      This patch replaces implementation by requiring runtime handlers to
      register power management and deferred initialization hooks with the
      core framework at runtime. The runtime services are to register the
      hooks only as the last step, after having all states successfully
      initialized.
      
      Change-Id: Ibe788a2a381ef39aec1d4af5ba02376e67269782
      7f366605
  30. 20 Feb, 2014 1 commit
    • Achin Gupta's avatar
      Rework arithmetic operations in Test Secure Payload · 916a2c1e
      Achin Gupta authored
      
      
      This patch reworks the service provided by the TSP to perform common
      arithmetic operations on a set of arguments provided by the non-secure
      world. For a addition, division, subtraction & multiplication operation
      requested on two arguments in x0 and x1 the steps are:
      
      1. TSPD saves the non-secure context and passes the operation and its
         arguments to the TSP.
      
      2. TSP asks the TSPD to return the same arguments once again. This
         exercises an additional SMC path.
      
      3. TSP now has two copies of both x0 and x1. It performs the operation
         on the corresponding copies i.e. in case of addition it returns x0+x0
         and x1+x1.
      
      4. TSPD receives the result, saves the secure context, restores the
         non-secure context and passes the result back to the non-secure
         client.
      
      Change-Id: I6eebfa2ae0a6f28b1d2e11a31f575c7a4b96724b
      Co-authored-by: default avatarJeenu Viswambharan <jeenu.viswambharan@arm.com>
      916a2c1e