1. 28 Feb, 2019 1 commit
  2. 18 Feb, 2019 1 commit
    • Antonio Nino Diaz's avatar
      Disable processor Cycle Counting in Secure state · ed4fc6f0
      Antonio Nino Diaz authored
      
      
      In a system with ARMv8.5-PMU implemented:
      
      - If EL3 is using AArch32, setting MDCR_EL3.SCCD to 1 disables counting
        in Secure state in PMCCNTR.
      
      - If EL3 is using AArch64, setting SDCR.SCCD to 1 disables counting in
        Secure state in PMCCNTR_EL0.
      
      So far this effect has been achieved by setting PMCR_EL0.DP (in AArch64)
      or PMCR.DP (in AArch32) to 1 instead, but this isn't considered secure
      as any EL can change that value.
      
      Change-Id: I82cbb3e48f2e5a55c44d9c4445683c5881ef1f6f
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      ed4fc6f0
  3. 06 Feb, 2019 1 commit
  4. 11 Jan, 2019 1 commit
    • Antonio Nino Diaz's avatar
      xlat v2: Dynamically detect need for CnP bit · 2559b2c8
      Antonio Nino Diaz authored
      
      
      ARMv8.2-TTCNP is mandatory from ARMv8.2 onwards, but it can be implemented
      in CPUs that don't implement all mandatory 8.2 features (and so have to
      claim to be a lower version).
      
      This patch removes usage of the ARM_ARCH_AT_LEAST() macro and uses system
      ID registers to detect whether it is needed to set the bit or not.
      
      Change-Id: I7bcbf0c7c937590dfc2ca668cfd9267c50f7d52c
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      2559b2c8
  5. 04 Jan, 2019 2 commits
    • Antonio Nino Diaz's avatar
      Sanitise includes across codebase · 09d40e0e
      Antonio Nino Diaz authored
      Enforce full include path for includes. Deprecate old paths.
      
      The following folders inside include/lib have been left unchanged:
      
      - include/lib/cpus/${ARCH}
      - include/lib/el3_runtime/${ARCH}
      
      The reason for this change is that having a global namespace for
      includes isn't a good idea. It defeats one of the advantages of having
      folders and it introduces problems that are sometimes subtle (because
      you may not know the header you are actually including if there are two
      of them).
      
      For example, this patch had to be created because two headers were
      called the same way: e0ea0928 ("Fix gpio includes of mt8173 platform
      to avoid collision."). More recently, this patch has had similar
      problems: 46f9b2c3 ("drivers: add tzc380 support").
      
      This problem was introduced in commit 4ecca339
      
       ("Move include and
      source files to logical locations"). At that time, there weren't too
      many headers so it wasn't a real issue. However, time has shown that
      this creates problems.
      
      Platforms that want to preserve the way they include headers may add the
      removed paths to PLAT_INCLUDES, but this is discouraged.
      
      Change-Id: I39dc53ed98f9e297a5966e723d1936d6ccf2fc8f
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      09d40e0e
    • Antonio Nino Diaz's avatar
      Reorganize architecture-dependent header files · f5478ded
      Antonio Nino Diaz authored
      
      
      The architecture dependant header files in include/lib/${ARCH} and
      include/common/${ARCH} have been moved to /include/arch/${ARCH}.
      
      Change-Id: I96f30fdb80b191a51448ddf11b1d4a0624c03394
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      f5478ded
  6. 03 Jan, 2019 1 commit
  7. 10 Dec, 2018 1 commit
    • Jeenu Viswambharan's avatar
      AArch64: Use SSBS for CVE_2018_3639 mitigation · 48e1d350
      Jeenu Viswambharan authored
      
      
      The Armv8.5 extensions introduces PSTATE.SSBS (Speculation Store Bypass
      Safe) bit to mitigate against Variant 4 vulnerabilities. Although an
      Armv8.5 feature, this can be implemented by CPUs implementing earlier
      version of the architecture.
      
      With this patch, when both PSTATE.SSBS is implemented and
      DYNAMIC_WORKAROUND_CVE_2018_3639 is active, querying for
      SMCCC_ARCH_WORKAROUND_2 via. SMCCC_ARCH_FEATURES call would return 1 to
      indicate that mitigation on the PE is either permanently enabled or not
      required.
      
      When SSBS is implemented, SCTLR_EL3.DSSBS is initialized to 0 at reset
      of every BL stage. This means that EL3 always executes with mitigation
      applied.
      
      For Cortex A76, if the PE implements SSBS, the existing mitigation (by
      using a different vector table, and tweaking CPU ACTLR2) is not used.
      
      Change-Id: Ib0386c5714184144d4747951751c2fc6ba4242b6
      Signed-off-by: default avatarJeenu Viswambharan <jeenu.viswambharan@arm.com>
      48e1d350
  8. 26 Nov, 2018 1 commit
    • Antonio Nino Diaz's avatar
      Synchronise arch.h and arch_helpers.h with TF-A-Tests · 932b3ae2
      Antonio Nino Diaz authored
      
      
      The headers forked at some point in the past and have diverged a lot. In
      order to make it easier to share code between TF-A-Tests and TF-A, this
      patch synchronises most of the definitions in the mentioned headers.
      
      This is not a complete sync, it has to be followed by more cleanup.
      
      This patch also removes the read helpers for the AArch32 instructions
      ats1cpr and ats1hr (they are write-only).
      
      Change-Id: Id13ecd7aeb83bd2318cd47156d71a42f1c9f6ba2
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      932b3ae2
  9. 08 Nov, 2018 1 commit
    • Antonio Nino Diaz's avatar
      Standardise header guards across codebase · c3cf06f1
      Antonio Nino Diaz authored
      
      
      All identifiers, regardless of use, that start with two underscores are
      reserved. This means they can't be used in header guards.
      
      The style that this project is now to use the full name of the file in
      capital letters followed by 'H'. For example, for a file called
      "uart_example.h", the header guard is UART_EXAMPLE_H.
      
      The exceptions are files that are imported from other projects:
      
      - CryptoCell driver
      - dt-bindings folders
      - zlib headers
      
      Change-Id: I50561bf6c88b491ec440d0c8385c74650f3c106e
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      c3cf06f1
  10. 28 Sep, 2018 1 commit
  11. 20 Sep, 2018 1 commit
  12. 30 Aug, 2018 1 commit
    • Douglas Raillard's avatar
      backtrace: Introduce backtrace function · 0c62883f
      Douglas Raillard authored
      
      
      This function diplays the backtrace, the current EL and security state
      to allow a post-processing tool to choose the right binary to interpret
      the dump.
      
      The output can be fed to GNU addr2line to resolve function names given
      an ELF binary compiled with debug information. The "-i" flag is
      recommended to improve display in case of inlined functions. The *.dump
      files generated during the build process can also be used.
      
      The function works in AArch64 and AArch32. In AArch32 it only works in
      A32 mode (without T32 interworking), which is enforced in the Makefile.
      
      Sample output of a backtrace at EL3:
      
          BACKTRACE: START: function_name
          0: EL3: 0x798
          1: EL3: 0x538
          2: EL3: 0x550
          3: EL3: 0x55c
          4: EL3: 0x568
          5: EL3: 0x5a8
          6: EL3: 0xf4
          BACKTRACE: END: function_name
      
      In order to enable it the new option ENABLE_BACKTRACE must be set to 1.
      This option is set to 1 by default only in AArch64 debug builds. As
      usual, it can be overridden by the platform makefile and in the build
      command line.
      
      Change-Id: Icaff39b0e5188329728be2f3c72b868b2368e794
      Co-authored-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      Signed-off-by: default avatarDouglas Raillard <douglas.raillard@arm.com>
      0c62883f
  13. 10 Aug, 2018 1 commit
    • Antonio Nino Diaz's avatar
      xlat v2: Support the EL2 translation regime · 1a92a0e0
      Antonio Nino Diaz authored
      
      
      The translation library is useful elsewhere. Even though this repository
      doesn't exercise the EL2 support of the library, it is better to have it
      here as well to make it easier to maintain.
      
      enable_mmu_secure() and enable_mmu_direct() have been deprecated. The
      functions are still present, but they are behind ERROR_DEPRECATED and
      they call the new functions enable_mmu_svc_mon() and
      enable_mmu_direct_svc_mon().
      
      Change-Id: I13ad10cd048d9cc2d55e0fff9a5133671b67dcba
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      1a92a0e0
  14. 18 Jul, 2018 2 commits
    • Sandrine Bailleux's avatar
      Fix HCPTR.TCP11 bit definition · e62ea09b
      Sandrine Bailleux authored
      
      
      Change-Id: I98f23f6cebcf984b57efc5449b75ff702e1984a0
      Signed-off-by: default avatarSandrine Bailleux <sandrine.bailleux@arm.com>
      e62ea09b
    • Antonio Nino Diaz's avatar
      Fix types of arch.h definitions · 30399885
      Antonio Nino Diaz authored
      
      
      Define the values as unsigned int or unsigned long long based on the
      actual size of the register. This prevents subtle issues caused by
      having a type that is too small. For example:
      
          #define OPTION_ENABLE 0x3
          #define OPTION_SHIFT  32
      
          uint64_t mask = OPTION_ENABLE << OPTION_SHIFT;
      
      Because OPTION_ENABLE fits in an int, the value is considered an int.
      This means that, after shifting it 32 places to the left, the final
      result is 0. The correct way to define the values is:
      
          #define OPTION_ENABLE ULL(0x3)
          #define OPTION_SHIFT  U(32)
      
      In this case, the compiler is forced to use a 64 bit value from the
      start, so shifting it 32 places to the left results in the expected
      value.
      
      Change-Id: Ieaf2ffc2d8caa48c622db011f2aef549e713e019
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      30399885
  15. 27 Jun, 2018 1 commit
    • Jeenu Viswambharan's avatar
      xlat v2: Split MMU setup and enable · 0cc7aa89
      Jeenu Viswambharan authored
      
      
      At present, the function provided by the translation library to enable
      MMU constructs appropriate values for translation library, and programs
      them to the right registers. The construction of initial values,
      however, is only required once as both the primary and secondaries
      program the same values.
      
      Additionally, the MMU-enabling function is written in C, which means
      there's an active stack at the time of enabling MMU. On some systems,
      like Arm DynamIQ, having active stack while enabling MMU during warm
      boot might lead to coherency problems.
      
      This patch addresses both the above problems by:
      
        - Splitting the MMU-enabling function into two: one that sets up
          values to be programmed into the registers, and another one that
          takes the pre-computed values and writes to the appropriate
          registers. With this, the primary effectively calls both functions
          to have the MMU enabled, but secondaries only need to call the
          latter.
      
        - Rewriting the function that enables MMU in assembly so that it
          doesn't use stack.
      
      This patch fixes a bunch of MISRA issues on the way.
      
      Change-Id: I0faca97263a970ffe765f0e731a1417e43fbfc45
      Signed-off-by: default avatarJeenu Viswambharan <jeenu.viswambharan@arm.com>
      0cc7aa89
  16. 20 Jun, 2018 1 commit
    • Soby Mathew's avatar
      ARM Platforms: Update CNTFRQ register in CNTCTLBase frame · 342d6220
      Soby Mathew authored
      
      
      Currently TF-A doesn't initialise CNTFRQ register in CNTCTLBase
      frame of the system timer. ARM ARM states that "The instance of
      the register in the CNTCTLBase frame must be programmed with this
      value as part of system initialization."
      
      The psci_arch_setup() updates the CNTFRQ system register but
      according to the ARM ARM, this instance of the register is
      independent of the memory mapped instance. This is only an issue
      for Normal world software which relies on the memory mapped
      instance rather than the system register one.
      
      This patch resolves the issue for ARM platforms.
      
      The patch also solves a related issue on Juno, wherein
      CNTBaseN.CNTFRQ can be written and does not reflect the value of
      the register in CNTCTLBase frame. Hence this patch additionally
      updates CNTFRQ register in the Non Secure frame of the CNTBaseN.
      
      Fixes ARM-Software/tf-issues#593
      
      Change-Id: I09cebb6633688b34d5b1bc349fbde4751025b350
      Signed-off-by: default avatarSoby Mathew <soby.mathew@arm.com>
      342d6220
  17. 31 Jan, 2018 2 commits
  18. 18 Jan, 2018 1 commit
    • Dimitris Papastamos's avatar
      sp_min: Implement workaround for CVE-2017-5715 · 7343505d
      Dimitris Papastamos authored
      
      
      This patch introduces two workarounds for ARMv7 systems.  The
      workarounds need to be applied prior to any `branch` instruction in
      secure world.  This is achieved using a custom vector table where each
      entry is an `add sp, sp, #1` instruction.
      
      On entry to monitor mode, once the sequence of `ADD` instructions is
      executed, the branch target buffer (BTB) is invalidated.  The bottom
      bits of `SP` are then used to decode the exception entry type.
      
      A side effect of this change is that the exception vectors are
      installed before the CPU specific reset function.  This is now
      consistent with how it is done on AArch64.
      
      Note, on AArch32 systems, the exception vectors are typically tightly
      integrated with the secure payload (e.g. the Trusted OS).  This
      workaround will need porting to each secure payload that requires it.
      
      The patch to modify the AArch32 per-cpu vbar to the corresponding
      workaround vector table according to the CPU type will be done in a
      later patch.
      
      Change-Id: I5786872497d359e496ebe0757e8017fa98f753fa
      Signed-off-by: default avatarDimitris Papastamos <dimitris.papastamos@arm.com>
      7343505d
  19. 29 Nov, 2017 1 commit
  20. 08 Nov, 2017 1 commit
  21. 16 Oct, 2017 1 commit
  22. 13 Oct, 2017 1 commit
    • David Cunado's avatar
      Init and save / restore of PMCR_EL0 / PMCR · 3e61b2b5
      David Cunado authored
      
      
      Currently TF does not initialise the PMCR_EL0 register in
      the secure context or save/restore the register.
      
      In particular, the DP field may not be set to one to prohibit
      cycle counting in the secure state, even though event counting
      generally is prohibited via the default setting of MDCR_EL3.SMPE
      to 0.
      
      This patch initialises PMCR_EL0.DP to one in the secure state
      to prohibit cycle counting and also initialises other fields
      that have an architectually UNKNOWN reset value.
      
      Additionally, PMCR_EL0 is added to the list of registers that are
      saved and restored during a world switch.
      
      Similar changes are made for PMCR for the AArch32 execution state.
      
      NOTE: secure world code at lower ELs that assume other values in PMCR_EL0
      will be impacted.
      
      Change-Id: Iae40e8c0a196d74053accf97063ebc257b4d2f3a
      Signed-off-by: default avatarDavid Cunado <david.cunado@arm.com>
      3e61b2b5
  23. 11 Sep, 2017 1 commit
  24. 24 Aug, 2017 1 commit
    • Isla Mitchell's avatar
      Enable CnP bit for ARMv8.2 CPUs · 9fce2725
      Isla Mitchell authored
      
      
      This patch enables the CnP (Common not Private) bit for secure page
      tables so that multiple PEs in the same Inner Shareable domain can use
      the same translation table entries for a given stage of translation in
      a particular translation regime. This only takes effect when ARM
      Trusted Firmware is built with ARM_ARCH_MINOR >= 2.
      
      ARM Trusted Firmware Design has been updated to include a description
      of this feature usage.
      
      Change-Id: I698305f047400119aa1900d34c65368022e410b8
      Signed-off-by: default avatarIsla Mitchell <isla.mitchell@arm.com>
      9fce2725
  25. 21 Jun, 2017 1 commit
    • David Cunado's avatar
      Fully initialise essential control registers · 18f2efd6
      David Cunado authored
      
      
      This patch updates the el3_arch_init_common macro so that it fully
      initialises essential control registers rather then relying on hardware
      to set the reset values.
      
      The context management functions are also updated to fully initialise
      the appropriate control registers when initialising the non-secure and
      secure context structures and when preparing to leave EL3 for a lower
      EL.
      
      This gives better alignement with the ARM ARM which states that software
      must initialise RES0 and RES1 fields with 0 / 1.
      
      This patch also corrects the following typos:
      
      "NASCR definitions" -> "NSACR definitions"
      
      Change-Id: Ia8940b8351dc27bc09e2138b011e249655041cfc
      Signed-off-by: default avatarDavid Cunado <david.cunado@arm.com>
      18f2efd6
  26. 03 May, 2017 1 commit
  27. 20 Apr, 2017 2 commits
  28. 27 Mar, 2017 1 commit
    • Summer Qin's avatar
      ARM platforms: Add support for MT bit in MPIDR · d8d6cf24
      Summer Qin authored
      
      
      This patch modifies some of the functions in ARM platform layer to cater
      for the case when multi-threading `MT` is set in MPIDR. A new build flag
      `ARM_PLAT_MT` is added, and when enabled, the functions accessing MPIDR
      now assume that the `MT` bit is set for the platform and access the bit
      fields accordingly.
      
      Also, a new API plat_arm_get_cpu_pe_count is added when `ARM_PLAT_MT` is
      enabled, returning the PE count within the physical cpu corresponding to
      `mpidr`.
      
      Change-Id: I04ccf212ac3054a60882761f4087bae299af13cb
      Signed-off-by: default avatarSummer Qin <summer.qin@arm.com>
      d8d6cf24
  29. 08 Mar, 2017 1 commit
    • Antonio Nino Diaz's avatar
      Add dynamic region support to xlat tables lib v2 · 0b64f4ef
      Antonio Nino Diaz authored
      
      
      Added APIs to add and remove regions to the translation tables
      dynamically while the MMU is enabled. Only static regions are allowed
      to overlap other static ones (for backwards compatibility).
      
      A new private attribute (MT_DYNAMIC / MT_STATIC) has been added to
      flag each region as such.
      
      The dynamic mapping functionality can be enabled or disabled when
      compiling by setting the build option PLAT_XLAT_TABLES_DYNAMIC to 1
      or 0. This can be done per-image.
      
      TLB maintenance code during dynamic table mapping and unmapping has
      also been added.
      
      Fixes ARM-software/tf-issues#310
      
      Change-Id: I19e8992005c4292297a382824394490c5387aa3b
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      0b64f4ef
  30. 15 Feb, 2017 1 commit
    • dp-arm's avatar
      Disable secure self-hosted debug via MDCR_EL3/SDCR · 85e93ba0
      dp-arm authored
      
      
      Trusted Firmware currently has no support for secure self-hosted
      debug.  To avoid unexpected exceptions, disable software debug
      exceptions, other than software breakpoint instruction exceptions,
      from all exception levels in secure state.  This applies to both
      AArch32 and AArch64 EL3 initialization.
      
      Change-Id: Id097e54a6bbcd0ca6a2be930df5d860d8d09e777
      Signed-off-by: default avatardp-arm <dimitris.papastamos@arm.com>
      85e93ba0
  31. 01 Dec, 2016 1 commit
    • David Cunado's avatar
      Reset EL2 and EL3 configurable controls · 939f66d6
      David Cunado authored
      
      
      This patch resets EL2 and EL3 registers that have architecturally
      UNKNOWN values on reset and that also provide EL2/EL3 configuration
      and trap controls.
      
      Specifically, the EL2 physical timer is disabled to prevent timer
      interrups into EL2 - CNTHP_CTL_EL2 and CNTHP_CTL for AArch64 and AArch32,
      respectively.
      
      Additionally, for AArch64, HSTR_EL2 is reset to avoid unexpected traps of
      non-secure access to certain system registers at EL1 or lower.
      
      For AArch32, the patch also reverts the reset to SDCR which was
      incorrectly added in a previous change.
      
      Change-Id: If00eaa23afa7dd36a922265194ccd6223187414f
      Signed-off-by: default avatarDavid Cunado <david.cunado@arm.com>
      939f66d6
  32. 09 Nov, 2016 1 commit
    • David Cunado's avatar
      Reset debug registers MDCR-EL3/SDCR and MDCR_EL2/HDCR · 495f3d3c
      David Cunado authored
      
      
      In order to avoid unexpected traps into EL3/MON mode, this patch
      resets the debug registers, MDCR_EL3 and MDCR_EL2 for AArch64,
      and SDCR and HDCR for AArch32.
      
      MDCR_EL3/SDCR is zero'ed when EL3/MON mode is entered, at the
      start of BL1 and BL31/SMP_MIN.
      
      For MDCR_EL2/HDCR, this patch zero's the bits that are
      architecturally UNKNOWN values on reset. This is done when
      exiting from EL3/MON mode but only on platforms that support
      EL2/HYP mode but choose to exit to EL1/SVC mode.
      
      Fixes ARM-software/tf-issues#430
      
      Change-Id: Idb992232163c072faa08892251b5626ae4c3a5b6
      Signed-off-by: default avatarDavid Cunado <david.cunado@arm.com>
      495f3d3c
  33. 14 Oct, 2016 1 commit
    • Soby Mathew's avatar
      Unify SCTLR initialization for AArch32 normal world · b7b0787d
      Soby Mathew authored
      
      
      The values of CP15BEN, nTWI & nTWE bits in SCTLR_EL1 are architecturally
      unknown if EL3 is AARCH64 whereas they reset to 1 if EL3 is AArch32. This
      might be a compatibility break for legacy AArch32 normal world software if
      these bits are not set to 1 when EL3 is AArch64. This patch enables the
      CP15BEN, nTWI and nTWE bits in the SCTLR_EL1 if the lower non-secure EL is
      AArch32. This unifies the SCTLR settings for lower non-secure EL in AArch32
      mode for both AArch64 and AArch32 builds of Trusted Firmware.
      
      Fixes ARM-software/tf-issues#428
      
      Change-Id: I3152d1580e4869c0ea745c5bd9da765f9c254947
      Signed-off-by: default avatarSoby Mathew <soby.mathew@arm.com>
      b7b0787d
  34. 21 Sep, 2016 1 commit
    • Yatharth Kochar's avatar
      AArch32: Common changes needed for BL1/BL2 · 1a0a3f06
      Yatharth Kochar authored
      This patch adds common changes to support AArch32 state in
      BL1 and BL2. Following are the changes:
      
      * Added functions for disabling MMU from Secure state.
      * Added AArch32 specific SMC function.
      * Added semihosting support.
      * Added reporting of unhandled exceptions.
      * Added uniprocessor stack support.
      * Added `el3_entrypoint_common` macro that can be
        shared by BL1 and BL32 (SP_MIN) BL stages. The
        `el3_entrypoint_common` is similar to the AArch64
        counterpart with the main difference in the assembly
        instructions and the registers that are relevant to
        AArch32 execution state.
      * Enabled `LOAD_IMAGE_V2` flag in Makefile for
        `ARCH=aarch32` and added check to make sure that
        platform has not overridden to disable it.
      
      Change-Id: I33c6d8dfefb2e5d142fdfd06a0f4a7332962e1a3
      1a0a3f06
  35. 23 Aug, 2016 1 commit
    • Antonio Nino Diaz's avatar
      Automatically select initial xlation lookup level · e8719552
      Antonio Nino Diaz authored
      Instead of hardcoding a level 1 table as the base translation level
      table, let the code decide which level is the most appropriate given
      the virtual address space size.
      
      As the table granularity is 4 KB, this allows the code to select
      level 0, 1 or 2 as base level for AArch64. This way, instead of
      limiting the virtual address space width to 39-31 bits, widths of
      48-25 bit can be used.
      
      For AArch32, this change allows the code to select level 1 or 2
      as the base translation level table and use virtual address space
      width of 32-25 bits.
      
      Also removed some unused definitions related to translation tables.
      
      Fixes ARM-software/tf-issues#362
      
      Change-Id: Ie3bb5d6d1a4730a26700b09827c79f37ca3cdb65
      e8719552
  36. 10 Aug, 2016 1 commit
    • Soby Mathew's avatar
      AArch32: Add essential Arch helpers · 031dbb12
      Soby Mathew authored
      This patch adds the essential AArch32 architecture helpers
      arch.h and arch_helpers.h and modifies `_types.h` to add AArch32
      support.
      
      A new build option `ARCH` is defined in the top level makefile to
      enable the component makefiles to choose the right files based on the
      Architecture it is being build for. Depending on this flag, either
      `AARCH32` or `AARCH64` flag is defined by the Makefile. The default
      value of `ARCH` flag is `aarch64`. The AArch32 build support will be
      added in a later patch.
      
      Change-Id: I405e5fac02db828a55cd25989b572b64cb005241
      031dbb12