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2020-02-09plat: imx8mq: move the stack & xlat table into ocram_sJacky Bai
Move the stack & xlat table into ocram_s due to the ocram is not enough. Signed-off-by: Jacky Bai <ping.bai@nxp.com>
2019-12-13imx: initialize register value before writting MU_SR registerAnson Huang
MU_SR register bit[30] is cold boot flag passed from SCU, w0 is random value and would clear the flag incorrectly, and cause system partition reboot fail if Linux is in suspend. So this patch initializes it to 0x80000000 which is exactly the same with first time board power up before writting to MU_SR register. Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
2019-12-13imx8qm: turn off A53 cluster for cpu hotplugAnson Huang
The issue of A53 cluster runtime power ON/OFF has been identified as fifo reset issue, and there is software workaround to avoid such issue and A53 cluster now can be turned OFF. Signed-off-by: Nitin Garg <nitin.garg@nxp.com> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
2019-10-04Neoverse N1 Errata Workaround 1542419laurenw-arm
Coherent I-cache is causing a prefetch violation where when the core executes an instruction that has recently been modified, the core might fetch a stale instruction which violates the ordering of instruction fetches. The workaround includes an instruction sequence to implementation defined registers to trap all EL0 IC IVAU instructions to EL3 and a trap handler to execute a TLB inner-shareable invalidation to an arbitrary address followed by a DSB. Signed-off-by: Lauren Wehrmeister <lauren.wehrmeister@arm.com> Change-Id: Ic3b7cbb11cf2eaf9005523ef5578a372593ae4d6
2019-09-13Refactor ARMv8.3 Pointer Authentication support codeAlexei Fedorov
This patch provides the following features and makes modifications listed below: - Individual APIAKey key generation for each CPU. - New key generation on every BL31 warm boot and TSP CPU On event. - Per-CPU storage of APIAKey added in percpu_data[] of cpu_data structure. - `plat_init_apiakey()` function replaced with `plat_init_apkey()` which returns 128-bit value and uses Generic timer physical counter value to increase the randomness of the generated key. The new function can be used for generation of all ARMv8.3-PAuth keys - ARMv8.3-PAuth specific code placed in `lib\extensions\pauth`. - New `pauth_init_enable_el1()` and `pauth_init_enable_el3()` functions generate, program and enable APIAKey_EL1 for EL1 and EL3 respectively; pauth_disable_el1()` and `pauth_disable_el3()` functions disable PAuth for EL1 and EL3 respectively; `pauth_load_bl31_apiakey()` loads saved per-CPU APIAKey_EL1 from cpu-data structure. - Combined `save_gp_pauth_registers()` function replaces calls to `save_gp_registers()` and `pauth_context_save()`; `restore_gp_pauth_registers()` replaces `pauth_context_restore()` and `restore_gp_registers()` calls. - `restore_gp_registers_eret()` function removed with corresponding code placed in `el3_exit()`. - Fixed the issue when `pauth_t pauth_ctx` structure allocated space for 12 uint64_t PAuth registers instead of 10 by removal of macro CTX_PACGAKEY_END from `include/lib/el3_runtime/aarch64/context.h` and assigning its value to CTX_PAUTH_REGS_END. - Use of MODE_SP_ELX and MODE_SP_EL0 macro definitions in `msr spsel` instruction instead of hard-coded values. - Changes in documentation related to ARMv8.3-PAuth and ARMv8.5-BTI. Change-Id: Id18b81cc46f52a783a7e6a09b9f149b6ce803211 Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>
2019-09-11Add UBSAN support and handlersJustin Chadwell
This patch adds support for the Undefined Behaviour sanitizer. There are two types of support offered - minimalistic trapping support which essentially immediately crashes on undefined behaviour and full support with full debug messages. The full support relies on ubsan.c which has been adapted from code used by OPTEE. Change-Id: I417c810f4fc43dcb56db6a6a555bfd0b38440727 Signed-off-by: Justin Chadwell <justin.chadwell@arm.com>
2019-08-29Move assembly newline function into common debug codeJustin Chadwell
Printing a newline is a relatively common functionality for code to want to do. Therefore, this patch now moves this function into a common part of the code that anyone can use. Change-Id: I2cad699fde00ef8d2aabf8bf35742ddd88d090ba Signed-off-by: Justin Chadwell <justin.chadwell@arm.com>
2019-08-23Merge "AArch64: Disable Secure Cycle Counter" into integrationPaul Beesley
2019-08-21AArch64: Disable Secure Cycle CounterAlexei Fedorov
This patch fixes an issue when secure world timing information can be leaked because Secure Cycle Counter is not disabled. For ARMv8.5 the counter gets disabled by setting MDCR_El3.SCCD bit on CPU cold/warm boot. For the earlier architectures PMCR_EL0 register is saved/restored on secure world entry/exit from/to Non-secure state, and cycle counting gets disabled by setting PMCR_EL0.DP bit. 'include\aarch64\arch.h' header file was tided up and new ARMv8.5-PMU related definitions were added. Change-Id: I6f56db6bc77504634a352388990ad925a69ebbfa Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>
2019-08-15AArch64: Align crash reporting outputAlexei Fedorov
This patch modifies crash reporting for AArch64 to provide aligned output of register dump and GIC registers. Change-Id: I8743bf1d2d6d56086e735df43785ef28051c5fc3 Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>
2019-07-22Fix BL31 crash reporting on AArch64 only machinesImre Kis
The AArch32 system registers are not listed if the platform supports AArch64 only. Change-Id: I087a10ae6e7cad1bb52775a344635dbac1f12679 Signed-off-by: Imre Kis <imre.kis@arm.com>
2019-05-24Add support for Branch Target IdentificationAlexei Fedorov
This patch adds the functionality needed for platforms to provide Branch Target Identification (BTI) extension, introduced to AArch64 in Armv8.5-A by adding BTI instruction used to mark valid targets for indirect branches. The patch sets new GP bit [50] to the stage 1 Translation Table Block and Page entries to denote guarded EL3 code pages which will cause processor to trap instructions in protected pages trying to perform an indirect branch to any instruction other than BTI. BTI feature is selected by BRANCH_PROTECTION option which supersedes the previous ENABLE_PAUTH used for Armv8.3-A Pointer Authentication and is disabled by default. Enabling BTI requires compiler support and was tested with GCC versions 9.0.0, 9.0.1 and 10.0.0. The assembly macros and helpers are modified to accommodate the BTI instruction. This is an experimental feature. Note. The previous ENABLE_PAUTH build option to enable PAuth in EL3 is now made as an internal flag and BRANCH_PROTECTION flag should be used instead to enable Pointer Authentication. Note. USE_LIBROM=1 option is currently not supported. Change-Id: Ifaf4438609b16647dc79468b70cd1f47a623362e Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>
2019-05-21Rework smc_unknown return code path in smc_handlerMadhukar Pappireddy
The intention of this patch is to leverage the existing el3_exit() return routine for smc_unknown return path rather than a custom set of instructions. In order to leverage el3_exit(), the necessary counteraction (i.e., saving the system registers apart from GP registers) must be performed. Hence a series of instructions which save system registers( like SPSR_EL3, SCR_EL3 etc) to stack are moved to the top of group of instructions which essentially decode the OEN from the smc function identifier and obtain the specific service handler in rt_svc_descs_array. This ensures that the control flow for both known and unknown smc calls will be similar. Change-Id: I67f94cfcba176bf8aee1a446fb58a4e383905a87 Signed-off-by: Madhukar Pappireddy <madhukar.pappireddy@arm.com>
2019-04-05Fix restoration of PAuth contextAlexei Fedorov
Replace call to pauth_context_save() with pauth_context_restore() in case of unknown SMC call. Change-Id: Ib863d979faa7831052b33e8ac73913e2f661f9a0 Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>
2019-03-25PIE: Fix reloc at the beginning of bl31 entrypointLouis Mayencourt
The relocation fixup code must be called at the beginning of bl31 entrypoint to ensure that CPU specific reset handlers are fixed up for relocations. Change-Id: Icb04eacb2d4c26c26b08b768d871d2c82777babb Signed-off-by: Louis Mayencourt <louis.mayencourt@arm.com>
2019-03-18Restore PAuth context in case of unknown SMC callAlexei Fedorov
Change-Id: I8fb346743b7afddbb8bf5908db4f27ee5a26f99b Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>
2019-03-07BL31: Enable pointer authentication support in warm boot pathAlexei Fedorov
In the current Pointer Authentication support added in commit b86048c40cb7d9ccd7aeac1681945676a6dc36ff PAuth gets enabled in BL31 cold boot entrypoint only, (see bl31_entrypoint() in bl31\aarch64\bl31_entrypoint.S) but not in bl31_warm_entrypoint(). This results in EnIA bit [31] in SCTLR_EL3 not being set and pointer authentication disabled after CPU wake-up event. Fixes ARM-software/tf-issues#684 Change-Id: I27a67804764dfba2a6d72ca119ca2bcff4f536d6 Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>
2019-02-28Minor changes to documentation and commentsAntonio Nino Diaz
Fix some typos and clarify some sentences. Change-Id: Id276d1ced9a991b4eddc5c47ad9a825e6b29ef74 Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2019-02-27BL31: Enable pointer authentication supportAntonio Nino Diaz
The size increase after enabling options related to ARMv8.3-PAuth is: +----------------------------+-------+-------+-------+--------+ | | text | bss | data | rodata | +----------------------------+-------+-------+-------+--------+ | CTX_INCLUDE_PAUTH_REGS = 1 | +192 | +1536 | +0 | +0 | | | 0.3% | 3.1% | | | +----------------------------+-------+-------+-------+--------+ | ENABLE_PAUTH = 1 | +1848 | +1536 | +16 | +0 | | | 3.3% | 3.1% | 3.1% | | +----------------------------+-------+-------+-------+--------+ Results calculated with the following build configuration: make PLAT=fvp SPD=tspd DEBUG=1 \ SDEI_SUPPORT=1 \ EL3_EXCEPTION_HANDLING=1 \ TSP_NS_INTR_ASYNC_PREEMPT=1 \ CTX_INCLUDE_PAUTH_REGS=1 \ ENABLE_PAUTH=1 Change-Id: I43db7e509a4f39da6599ec2faa690d197573ec1b Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2019-02-27Add support for pointer authenticationAntonio Nino Diaz
The previous commit added the infrastructure to load and save ARMv8.3-PAuth registers during Non-secure <-> Secure world switches, but didn't actually enable pointer authentication in the firmware. This patch adds the functionality needed for platforms to provide authentication keys for the firmware, and a new option (ENABLE_PAUTH) to enable pointer authentication in the firmware itself. This option is disabled by default, and it requires CTX_INCLUDE_PAUTH_REGS to be enabled. Change-Id: I35127ec271e1198d43209044de39fa712ef202a5 Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2019-02-27Add ARMv8.3-PAuth registers to CPU contextAntonio Nino Diaz
ARMv8.3-PAuth adds functionality that supports address authentication of the contents of a register before that register is used as the target of an indirect branch, or as a load. This feature is supported only in AArch64 state. This feature is mandatory in ARMv8.3 implementations. This feature adds several registers to EL1. A new option called CTX_INCLUDE_PAUTH_REGS has been added to select if the TF needs to save them during Non-secure <-> Secure world switches. This option must be enabled if the hardware has the registers or the values will be leaked during world switches. To prevent leaks, this patch also disables pointer authentication in the Secure world if CTX_INCLUDE_PAUTH_REGS is 0. Any attempt to use it will be trapped in EL3. Change-Id: I27beba9907b9a86c6df1d0c5bf6180c972830855 Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2019-02-11Merge pull request #1810 from antonio-nino-diaz-arm/an/setjmpAntonio Niño Díaz
Make setjmp/longjmp compliant with the C standard and move them to libc
2019-02-08libc: Move setjmp to libc folderAntonio Nino Diaz
Now that setjmp() and longjmp() are compliant with the standard they can be moved with the other libc files. Change-Id: Iea3b91c34eb353ace5e171e72f331602d57774d5 Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2019-02-07locks: linker variables to calculate per-cpu bakery lock sizeVarun Wadekar
This patch introduces explicit linker variables to mark the start and end of the per-cpu bakery lock section to help bakery_lock_normal.c calculate the size of the section. This patch removes the previously used '__PERCPU_BAKERY_LOCK_SIZE__' linker variable to make the code uniform across GNU linker and ARM linker. Change-Id: Ie0c51702cbc0fe8a2076005344a1fcebb48e7cca Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
2019-01-30Remove support for the SMC Calling Convention 2.0Antonio Nino Diaz
This reverts commit 2f370465241c ("Add support for the SMC Calling Convention 2.0"). SMCCC v2.0 is no longer required for SPM, and won't be needed in the future. Removing it makes the SMC handling code less complicated. The SPM implementation based on SPCI and SPRT was using it, but it has been adapted to SMCCC v1.0. Change-Id: I36795b91857b2b9c00437cfbfed04b3c1627f578 Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2019-01-22SPM: Rename folder of SPM based on MMAntonio Nino Diaz
This implementation is no longer deprecated. Change-Id: I68552d0fd5ba9f08fad4345e4657e8e3c5362a36 Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2019-01-22SPM: Rename SPM_DEPRECATED flag to SPM_MMAntonio Nino Diaz
The SPM implementation based on MM is going to be kept for the foreseeable future. Change-Id: I11e96778a4f52a1aa803e7e048d9a7cb24a53954 Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com> Acked-by: Sumit Garg <sumit.garg@linaro.org>
2019-01-16Merge pull request #1738 from ardbiesheuvel/synquacer-spmSoby Mathew
synquacer: add SPM support
2019-01-15spm: permit platform to override the VMA placement of the vector tableArd Biesheuvel
On some systems, it may be preferred to place the secure EL1/0 vector table outside of the static placement of the BL31 image itself, for instance when the latter is located in non-shareable SRAM which does not tolerate inner shareable WBWA mappings (as is the case on SynQuacer) So permit the platform to #define SPM_SHIM_EXCEPTIONS_VMA in its supplementary linker script, in which case it will be used as the VMA region for the vector table. Note that the LMA does not change, and it is up to the platform to copy the contents to the right place at init time. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2019-01-15Correct typographical errorsPaul Beesley
Corrects typos in core code, documentation files, drivers, Arm platforms and services. None of the corrections affect code; changes are limited to comments and other documentation. Change-Id: I5c1027b06ef149864f315ccc0ea473e2a16bfd1d Signed-off-by: Paul Beesley <paul.beesley@arm.com>
2019-01-04Sanitise includes across codebaseAntonio Nino Diaz
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: e0ea0928d5b7 ("Fix gpio includes of mt8173 platform to avoid collision."). More recently, this patch has had similar problems: 46f9b2c3a282 ("drivers: add tzc380 support"). This problem was introduced in commit 4ecca33988b9 ("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: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2018-12-17BL31: correct GOT section omissionSoby Mathew
When the patch SHA 931f7c6 introduced PIE support for BL31, adding the GOT section when the SEPARATE_CODE_AND_RODATA=0 to the linker script was erroneously omitted. This patch corrects the same. Also the patch reduces the alignment requirement for GOT and RELA sections from 16 bytes to 8. Comments are added explain the intent for alignment. Change-Id: I8035cbf75f346f99bd56b13f32e0b3b70dd2fe6c Signed-off-by: Soby Mathew <soby.mathew@arm.com>
2018-12-11SPM: Introduce SMC handlers for SPCI and SPRTAntonio Nino Diaz
Change-Id: I2ae9b3bb686c41b2e138132a7bed107925ac861e Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2018-12-10SPM: Deprecate the current implementationAntonio Nino Diaz
The current SPM is a prototype that only supports one secure partition in EL0. The objective of SPM is to have multiple partitions. The current MM interface isn't adequate for this, so it is needed to modify heavily the code to add proper support for it. However, there are platforms which are already using this (like SGI) and removing the code would break it. For this reason, the current SPM code has been duplicated in order to temporarily preserve compatibility. All new improvements/changes to SPM will be done in the non-deprecated copy, that may change without notice. The new build option SPM_DEPRECATED has been introduced to select the SPM implementation. It defaults to 1, that selects the deprecated SPM. Change-Id: Ic9f80b53b450e97b4d3f47e4ef4a138ee8d87443 Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2018-12-05BL31: Use helper function to save registers in SMC handlerSoby Mathew
Use the helper function `save_gp_registers` to save the register state to cpu_context on entry to EL3 in SMC handler. This has the effect of saving x0 - x3 as well into the cpu_context which was not done previously but it unifies the register save sequence in BL31. Change-Id: I5753c942263a5f9178deda3dba896e3220f3dd83 Signed-off-by: Soby Mathew <soby.mathew@arm.com>
2018-11-14SPM: EHF: Build EHF module along with Secure Partition ManagerSughosh Ganu
Add a dependency for building EL3 exception handling framework(EHF) module with the secure partition manager(SPM). The EHF module is needed for raising the core's running priority before the core enters the secure partition, and lowering it subsequently on exit from the secure partition. Change-Id: Icbe2d0a63f00b46dc593ff3d86b676c9333506c3 Signed-off-by: Sughosh Ganu <sughosh.ganu@arm.com>
2018-11-01context_mgmt: Fix MISRA defectsAntonio Nino Diaz
The macro EL_IMPLEMENTED() has been deprecated in favour of the new function el_implemented(). Change-Id: Ic9b1b81480b5e019b50a050e8c1a199991bf0ca9 Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2018-10-29PIE: Position Independant Executable support for BL31Soby Mathew
This patch introduces Position Independant Executable(PIE) support in TF-A. As a initial prototype, only BL31 can support PIE. A trivial dynamic linker is implemented which supports fixing up Global Offset Table(GOT) and Dynamic relocations(.rela.dyn). The fixup_gdt_reloc() helper function implements this linker and this needs to be called early in the boot sequence prior to invoking C functions. The GOT is placed in the RO section of BL31 binary for improved security and the BL31 linker script is modified to export the appropriate symbols required for the dynamic linker. The C compiler always generates PC relative addresses to linker symbols and hence referencing symbols exporting constants are a problem when relocating the binary. Hence the reference to the `__PERCPU_TIMESTAMP_SIZE__` symbol in PMF is removed and is now calculated at runtime based on start and end addresses. Change-Id: I1228583ff92cf432963b7cef052e95d995cca93d Signed-off-by: Soby Mathew <soby.mathew@arm.com>
2018-10-16scmi: Optimize bakery locks when HW_ASSISTED_COHERENCY is enabledRoberto Vargas
When HW_ASSISTED_COHERENCY is enabled we can use spinlocks instead of using the more complex and slower bakery algorithm. Change-Id: I9d791a70050d599241169b9160a67e57d5506564 Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>
2018-10-04Remove some MISRA defects in common codeAntonio Nino Diaz
No functional changes. Change-Id: I9638e02acb9b22eb794ebf45aad84348a710287e Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2018-10-03Mark BL31 initialization functionsDaniel Boulby
Mark the initialization functions in BL31, such as context management, EHF, RAS and PSCI as __init so that they can be reclaimed by the platform when no longer needed Change-Id: I7446aeee3dde8950b0f410cb766b7a2312c20130 Signed-off-by: Daniel Boulby <daniel.boulby@arm.com>
2018-09-28context_mgmt: Remove deprecated interfacesAntonio Nino Diaz
Change-Id: I2d4a21a80a768bc422e9707e6d7e98d20a716275 Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2018-09-18BL31: Fix warning about BL32 init functionAntonio Nino Diaz
The expected value for failure is 0, so the warning only has to be shown in that case. This is the way the TSPD has done it since it was introduced, and the way SPM and OP-TEE do it. Trusty wrongly returns 0 on success. In the case of TLK, the return value of tlkd_init() is passed from the secure world in register X1 when calling the SMC TLK_ENTRY_DONE. Change-Id: I39106d67631ee57f109619f8830bf4b9d96155e6 Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2018-09-06Convert BL31 error message into warningAntonio Nino Diaz
If BL32 isn't present or it fails to initialize the current code prints an error message in both debug and release builds. This is too verbose for release builds, so it has been converted into a warning. Also, it was missing a newline at the end of the message. Change-Id: I91e18d5d5864dbb19d47ecd54f174d2d8c06296c Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2018-08-30Fix MISRA defects in BL31 common codeAntonio Nino Diaz
Change-Id: I5993b425445ee794e6d2a792c244c0af53640655 Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2018-08-22Merge pull request #1532 from jeenu-arm/misra-fixesDimitris Papastamos
MISRA fixes
2018-08-22Merge pull request #1533 from jeenu-arm/mpamDimitris Papastamos
AArch64: Enable MPAM for lower ELs
2018-08-20EHF: MISRA fixesJeenu Viswambharan
These changes address most of the required MISRA rules. In the process, some from generic code are also fixed. No functional changes. Change-Id: I19786070af7bc5e1f6d15bdba93e22a4451d8fe9 Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
2018-08-20AArch64: Enable MPAM for lower ELsJeenu Viswambharan
Memory Partitioning And Monitoring is an Armv8.4 feature that enables various memory system components and resources to define partitions. Software running at various ELs can then assign themselves to the desired partition to control their performance aspects. With this patch, when ENABLE_MPAM_FOR_LOWER_ELS is set to 1, EL3 allows lower ELs to access their own MPAM registers without trapping to EL3. This patch however doesn't make use of partitioning in EL3; platform initialisation code should configure and use partitions in EL3 if required. Change-Id: I5a55b6771ccaa0c1cffc05543d2116b60cbbcdcd Co-authored-by: James Morse <james.morse@arm.com> Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
2018-08-17DSU erratum 936184 workaroundJohn Tsichritzis
If the system is in near idle conditions, this erratum could cause a deadlock or data corruption. This patch applies the workaround that prevents this. This DSU erratum affects only the DSUs that contain the ACP interface and it was fixed in r2p0. The workaround is applied only to the DSUs that are actually affected. Link to respective Arm documentation: http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.epm138168/index.html Change-Id: I033213b3077685130fc1e3f4f79c4d15d7483ec9 Signed-off-by: John Tsichritzis <john.tsichritzis@arm.com>