BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3223
In the current design, memory protection is not available till CpuDxe
is loaded. To resolve this, introduce CpuArchLib to move the
CPU Architectural initialization to DxeCore.
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Vitaly Cheptsov <vit9696@protonmail.com>
Signed-off-by: Marvin Häuser <mhaeuser@posteo.de>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3704
build -a X64 -t CLANG38 -b RELEASE -p OvmfPkg/OvmfPkgX64.dsc
results in
UDK/MdeModulePkg/Library/UefiBootManagerLib/BmBoot.c:1284:31:
error: variable 'Status' set but not used
[-Werror,-Wunused-but-set-variable]
Signed-off-by: Mikhail Krichanov <krichanov@ispras.ru>
MdePkg/DebugLib(PerformanceLib): Fix "unused-but-set-variable" warning
The current definitions of DEBUG_CODE_BEGIN() and DEBUG_CODE_END() use
the local
variable __DebugCodeLocal as an attempt to track parity. If
DEBUG_CODE_END() is
used without a preceding DEBUG_CODE_BEGIN(), __DebugCodeLocal will not
have been
declared and a compilation error will be issued. The mutations of the
variable
are not used to track nesting or such. As the value of this variable is
never
actually used, recent Clang versions issue a "unused-but-set-variable"
warning
for it.
To solve this, re-define __DebugCodeLocal as a BOOLEAN that is always
FALSE and
use it in a do-while loop condition as done explicitly in many places.
Like the
previous solution, DEBUG_CODE_END() cannot be used without
DEBUG_CODE_BEGIN(),
as __DebugCodeLocal will be not have been defined.
Signed-off-by: Marvin Häuser <mhaeuser@posteo.de>
ArmVirtQemu may execute at EL2, in which case monitor calls are
generally made using SMC instructions instead of HVC instructions.
Whether or not this is the case can only be decided at runtime, and so
the associated PCD needs to be settable at runtime, if the platform
definition chooses so. This implies a boolean PCD, given that a feature
PCD is build-time configurable only.
Cc: Leif Lindholm <quic_llindhol@quicinc.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Sami Mujawar <sami.mujawar@arm.com>
Committed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Doug Flick [MSFT] <doug.edk2@gmail.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
The last reference to ArmCortexA9.h in the edk2 repository
was removed in:
a913ad0247 ("ArmPlatformPkg: remove ArmVExpressPkg")
The last reference to the file in the edk2-platforms
repository was agreed to be dropped:
https://edk2.groups.io/g/devel/message/115378
Cc: Leif Lindholm <quic_llindhol@quicinc.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Sami Mujawar <sami.mujawar@arm.com>
Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>
The last reference to ArmCortexA5x.h was removed in:
commit: cffa7925a2 ("ArmPkg: remove ArmCpuLib header
and implementations")
There are no reference to the file in the edk2-platforms
repository. Remove the file.
Cc: Leif Lindholm <quic_llindhol@quicinc.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Sami Mujawar <sami.mujawar@arm.com>
Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>
Taking reference from Table 2-1 of the Arm Generic Interrupt Controller
Architecture Specification, Issue H, January 2022, add macros for the
SPI and extended SPI ranges with the purpose of reusability on including
the ArmPkg.
Cc: Leif Lindholm <quic_llindhol@quicinc.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Sami Mujawar <sami.mujawar@arm.com>
Signed-off-by: Himanshu Sharma <Himanshu.Sharma@arm.com>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>
Reviewed-by: Pierre Gondois <pierre.gondois@arm.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Update GenericWatchdogDxe to disable watchdog interaction after exiting
boot services. Also, move the mEfiExitBootServicesEvent event to the top
of the file with the other static variables.
Signed-off-by: Rebecca Cran <rebecca@os.amperecomputing.com>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>
The calculation of the timer period was broken. Introduce a global
mTimerPeriod so the calculation can be removed. Since mTimerFrequencyHz
is only used in one place, remove the global and make it a local
variable. Do the same with mNumTimerTicks.
Signed-off-by: Rebecca Cran <rebecca@os.amperecomputing.com>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>
The generic watchdog offset register is 48 bits wide, and can be set by
performing two 32-bit writes.
Add support for writing the high 16 bits of the offset register and
update the signature of the WatchdogWriteOffsetRegister function to take
a UINT64 value.
Signed-off-by: Rebecca Cran <rebecca@os.amperecomputing.com>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>
The PERFORMANCE_DESCRIBE_FASTCHANNEL Scmi command is available
since SCMI v2.0 and allows to query information about the supported
fast-channels of the Scmi performance protocol.
Add support for this command.
Also move SCMI_MESSAGE_ID_PERFORMANCE enum definition up in the file
to use it in SCMI_PERFORMANCE_DESCRIBE_FASTCHANNEL function
declaration.
Reviewed-by: Leif Lindholm <quic_llindhol@quicinc.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>
Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Rename PERFORMANCE_PROTOCOL_VERSION to reflect the different
versions of the protocol. The macro is neither used in edk2 nor
in edk2-platforms.
Reviewed-by: Leif Lindholm <quic_llindhol@quicinc.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>
Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
The DebugPeCoffExtraActionLib implemention in ArmPkg contains some cruft
that dates back to the original RVCT based ARM port, and support for
RVCT was dropped a while ago.
Also drop the handling of Cygwin specific paths, which is highly
unlikely to be still depended upon by anyone.
Tweak the logic so that only two versions of the DEBUG() invocations
remain: one for __GNUC__ when PdbPointer is set, and the fallback that
just prints the image address and the address of the entrypoint.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Leif Lindholm <quic_llindhol@quicinc.com>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>
GetNextEntryAttribute() is currently applying a 64-bit mask
(TT_ATTRIBUTES_MASK) to a 32-bit descriptor value (EntryType).
The original descriptor was 64 bits containing the upper and
lower attributes which are included in TT_ATTRIBUTES_MASK.
The PrevEntryAttribute parameter is also a UINT32, but passed to
PageAttributeToGcdAttribute() for a UINT64 parameter where the
function checks masks in the upper 32 bits of the integer value:
PageAttributeToGcdAttribute (*PrevEntryAttribute)
...
STATIC
UINT64
PageAttributeToGcdAttribute (
IN UINT64 PageAttributes
)
...
if ((PageAttributes & (TT_PXN_MASK | TT_UXN_MASK)) != 0) {
GcdAttributes |= EFI_MEMORY_XP;
}
...
#define TT_PXN_MASK BIT53
#define TT_UXN_MASK BIT54 // EL1&0
This change removes UINT32 intermediary values. For EntryType,
eliminating an unncessary cast. For EntryAttribute, preserving the
upper and lower attributes for evaluation in
PageAttributeToGcdAttribute().
This also resolves the following compiler warning previously present
on Visual Studio for the assignment to the previously 32-bit local
variables.
'=': conversion from 'UINT64' to 'UINT32', possible loss of data
Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
mReplaceLiveEntryFunc is a function pointer but assigned as a VOID*
pointer:
mReplaceLiveEntryFunc = *(VOID **)GET_GUID_HOB_DATA (Hob);
This leads to the Visual Studio warning:
nonstandard extension, function/data pointer conversion in
expression
This change updates the assignment to avoid using a data pointer and
defines a type for the function pointer to succinctly and accurately
refer to the type when it is used in the library code.
Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Create a helper function to query whether ID_AA64MFR1_EL1 indicates
presence of the Embedded Trace Extension (ETE). This feature is only
visible in AARCH64 state.
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Leif Lindholm <quic_llindhol@quicinc.com>
Cc: Pierre Gondois <pierre.gondois@arm.com>
Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
Reviewed-by: Leif Lindholm <quic_llindhol@quicinc.com>
Reviewed-by: Pierre Gondois <pierre.gondois@arm.com>
Create a helper function to query whether ID_AA64MFR1_EL1 indicates
presence of the Trace Buffer Extension (TRBE). This feature is only
visible in AARCH64 state.
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Leif Lindholm <quic_llindhol@quicinc.com>
Cc: Pierre Gondois <pierre.gondois@arm.com>
Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
Reviewed-by: Leif Lindholm <quic_llindhol@quicinc.com>
Reviewed-by: Pierre Gondois <pierre.gondois@arm.com>
Add EFI_NOT_READY return if the CPU can not be enabled because the
processor is already on.
This can occur in normal use if the CPU is still being turned off from
a previous call when this is called again.
Signed-off-by: Jeff Brasen <jbrasen@nvidia.com>
Reviewed-by: Rebecca Cran <rebecca@bsdio.com>
Create a helper function to query whether ID_AA64MFR1_EL1 indicates
presence of the Virtualization Host Extensions. This feature is only
visible in AARCH64 state.
Signed-off-by: Leif Lindholm <quic_llindhol@quicinc.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Sami Mujawar <sami.mujawar@arm.com>
Cc: Marcin Juszkiewicz <marcin.juszkiewicz@linaro.org>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>
Tested-by: Marcin Juszkiewicz <marcin.juszkiewicz@linaro.org>
PcdArmArchTimerHypVirtIntrNum, defaults to 28 as defined in Arm's
Base System Architecture (current version DEN0094C 1.0C).
Relevant for systems implementing FEAT_VHE, added in ARMv8.1.
Signed-off-by: Leif Lindholm <quic_llindhol@quicinc.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Sami Mujawar <sami.mujawar@arm.com>
Signed-off-by: Leif Lindholm <quic_llindhol@quicinc.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Jake reports that the IS_ARM_MEMORY_REGION_ATTRIBUTES_SECURE() macro is
no longer accurate since commit 852227a9d5 ("ArmPkg/Mmu: Remove
handling of NONSECURE memory regions").
Fortunately, it only affects the NS bit in level 1 short descriptors,
which is ignored when executing in non-secure mode. And given that
running UEFI in the secure world is not a use case we aim to support,
let's just drop this logic altogether.
Reported-by: Jake Garver <jake@nvidia.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Leif Lindholm <quic_llindhol@quicinc.com>
I am moving this command outside of EDK2.
This reverts commit 2c2cb23528.
Signed-off-by: Marcin Juszkiewicz <marcin.juszkiewicz@linaro.org>
Reviewed-by: Leif Lindholm <quic_llindhol@quicinc.com>
The top two bits of the Extended BIOS ROM Size field indicates the unit
used for the remaining 14 bits. If the size is greater than 16GB, the
unit is gigabytes.
The test for this uses the local BiosPhysicalSize variable, which is a
UINTN, meaning that when building for ARM/CLANGDWARF we have a
tautological constant comparison, which the toolchain flags now we've
stopped disabling that warning.
So switch the BiosPhysicalSize variable to UINT64.
Signed-off-by: Leif Lindholm <quic_llindhol@quicinc.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Rebecca Cran <rebecca@bsdio.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
If gST->ConOut is available when Arm's DefaultExceptionHandler is
running, AsciiPrint will get called to attempt to print to ConOut, in
addition to the serial output.
AsciiPrint calls AsciiInternalPrint in UefiLibPrint.c which in turn
calls AllocatePool to allocate a buffer to convert the Ascii input
string to a Unicode string to pass to ConOut->OutputString.
Per the comment on DefaultExceptionHandler, we should not be allocating
memory in the exception handler, as this can cause the exception handler
to fail if we had a memory exception or the system state is such that we
cannot allocate memory.
It has been observed on ArmVirtQemu that exceptions generated in the
memory handling code will fail to output the stack dump and CPU state
that is critical to debugging because the AllocatePool will fail.
This patch fixes the Arm and AARCH64 DefaultExceptionHandlers to not
allocate memory when ConOut is available and instead use stack memory to
convert the Ascii string needed for SerialPortWrite to the Unicode
string needed for ConOut->OutputString. Correspondingly, ArmVirtQemu can
now output the stack dump and CPU state when hitting an exception in
memory code.
Signed-off-by: Oliver Smith-Denny <osde@linux.microsoft.com>
Much of the MMU logic was written without function headers. This patch
adds function headers where absent and updates function headers which
do not match the EDK2 standard.
Signed-off-by: Taylor Beebe <t@taylorbeebe.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
There are ASSERTs present in the MMU logic to ensure various
functions return successfully, but these ASSERTs may be ignored
on release builds causing unsafe behavior. This patch updates
the logic to handle unexpected return values and branch safely.
Signed-off-by: Taylor Beebe <t@taylorbeebe.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
This patch updates the GetMemoryRegion() function to handle the case
where there is no mapping for the requested address.
The original logic for the ARM would hit an ASSERT after
GetMemoryRegionPage() returned EFI_SUCCESS but did not update The
RegionLength parameter.
The original logic for the AARCH64 would never initialize the
RegionLength parameter to zero and return EFI_SUCCESS after
traversing an unknown number of pages.
To fix this, update the logic for both architecture to return
EFI_NO_MAPPING if the BaseAddress being checked is unmapped.
Signed-off-by: Taylor Beebe <t@taylorbeebe.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
This patch applies Uncrustify to the following files:
ArmPkg/Drivers/MmCommunicationPei/MmCommunicationPei.c
ArmPkg/Include/IndustryStandard/ArmStdSmc.h
Signed-off-by: Taylor Beebe <t@taylorbeebe.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4464
This change introduced the MM communicate support in PEI phase for ARM
based platforms. Similar to the DXE counterpart, `PcdMmBufferBase` is
used as communicate buffer and SMC will be invoked to communicate to
TrustZone when MMI is requested.
Cc: Leif Lindholm <quic_llindhol@quicinc.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Sami Mujawar <sami.mujawar@arm.com>
Co-authored-by: Ronny Hansen <hansen.ronny@microsoft.com>
Co-authored-by: Shriram Masanamuthu Chinnathurai <shriramma@microsoft.com>
Co-authored-by: Preshit Harlikar <pharlikar@microsoft.com>
Signed-off-by: Kun Qin <kuqin@microsoft.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
The OP-TEE secure OS exposes a non-secure memory region for
communication between the secure OS itself and any clients in the
non-secure firmware. This memory is writable by non-secure and is not
used for code only data, and so it should be mapped non-executable.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Leif Lindholm <quic_llindhol@quicinc.com>
Now that we have a sane API to set and clear memory permissions that
works the same on ARM and AArch64, we no longer have a need for the
individual set/clear no-access/read-only/no-exec helpers so let's drop
them.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Leif Lindholm <quic_llindhol@quicinc.com>
Now that ArmSetMemoryAttributes() permits a mask to be provided, we can
simplify the implementation the UEFI memory attribute protocol
substantially, and just pass on the requested mask to be set or cleared
directly.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Oliver Smith-Denny <osde@linux.microsoft.com>
Reviewed-by: Michael Kubacki <michael.kubacki@microsoft.com>
Implement the newly defined PPI that permits the PEI core and DXE IPL to
manage memory permissions on ranges of DRAM, for doing things like
mapping the stack non-executable, or granting executable permissions to
shadowed PEIMs.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Oliver Smith-Denny <osde@linux.microsoft.com>
Reviewed-by: Michael Kubacki <michael.kubacki@microsoft.com>
Currently, ArmSetMemoryAttributes () takes a combination of
EFI_MEMORY_xx constants describing the memory type and permission
attributes that should be set on a region of memory. In cases where the
memory type is omitted, we assume that the memory permissions being set
are final, and that existing memory permissions can be discarded.
This is problematic, because we aim to map memory non-executable
(EFI_MEMORY_XP) by default, and only relax this requirement for code
regions that are mapped read-only (EFI_MEMORY_RO). Currently, setting
one permission clears the other, and so code managing these permissions
has to be aware of the existing permissions in order to be able to
preserve them, and this is not always tractable (e.g., the UEFI memory
attribute protocol implements an abstraction that promises to preserve
memory permissions that it is not operating on explicitly).
So let's add an AttributeMask parameter to ArmSetMemoryAttributes(),
which is permitted to be non-zero if no memory type is being provided,
in which case only memory permission attributes covered in the mask will
be affected by the update.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Oliver Smith-Denny <osde@linux.microsoft.com>
Reviewed-by: Michael Kubacki <michael.kubacki@microsoft.com>
They are useful for those platforms where SMC SiP calls exist.
Signed-off-by: Marcin Juszkiewicz <marcin.juszkiewicz@linaro.org>
Reviewed-by: Leif Lindholm <quic_llindhol@quicinc.com>
Uncrustify checks are too rigid, making them counter-productive:
- it leads to code that is arguably harder to parse visually (e.g.,
the changes to ArmPkg/Include/Chipset/AArch64Mmu.h in commit
429309e0c6)
- it forces indentation-only changes to code in the vicinity of actual
changes, making the code history more bloated than necessary (see
commit 7f198321ee for an example)
- finding out from the web UI what exactly Uncrustify objected to is not
straight-forward.
So let's enable AuditMode for ArmPkg, so that interested parties can see
the uncrustify recommendations if desired, but without preventing the
changes from being merged. This leaves it at the discretion of the
ArmPkg maintainers to decide which level of conformance is required.
Cc: Leif Lindholm <quic_llindhol@quicinc.com>
Cc: "Kinney, Michael D" <michael.d.kinney@intel.com>
Cc: Michael Kubacki <mikuback@linux.microsoft.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Leif Lindholm <quic_llindhol@quicinc.com>
The ArmGicAcknowledgeInterrupt () returns the value returned by the
Interrupt Acknowledge Register and the InterruptID separately in an out
parameter.
The function documents the following: 'InterruptId is returned
separately from the register value because in the GICv2 the register
value contains the CpuId and InterruptId while in the GICv3 the register
value is only the InterruptId.'
This function skips setting the InterruptId in the out parameter for
GICv3. Although the return value from the function is the InterruptId
for GICv3, this breaks the function usage model as the caller expects
the InterruptId in the out parameter for the function. e.g. The caller
may end up using the InterruptID which could potentially be an
uninitialised variable value.
Therefore, set the InterruptID in the function out parameter for GICv3
as well.
Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
According to the GIC architecture version 3 and 4 specification, the
maximum number of INTID bits supported in the CPU interface is 24.
Considering this the RegShift variable is not required to be more than 8
bits. Therefore, make the RegShift variable type to UINT8. Also add
necessary typecasts when calculating the RegOffset and RegShift values.
Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
GICD_SGIR is a 32-bit register, of which INTID is bits [3:0] and Bits
[14:4] is RES0. Since SgiId parameter in the function ArmGicSendSgiTo ()
is UINT8, mask unused bits of SgiId before writing to the GICD_SGIR
register to prevent accidental setting of the RES0 bits.
Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
The IrqInterruptHandler () and ExitBootServicesEvent () function
declarations were unused. Therefore, remove these declarations.
Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
The EIOR register of the Gic CPU interface is a 32 bit register.
However, the HARDWARE_INTERRUPT_SOURCE used to represent the interrupt
source (Interrupt ID) is typedefed as UINTN, see
EmbeddedPkg\Include\Protocol\HardwareInterrupt.h
Therfore, typecast the interrupt ID (Source) value to UINT32 before
setting the EOIR register. Also, add an assert to check that the value
does not exceed 32 bits.
Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
Although the maximum interrupt ID on GicV2 is 10bit and for GicV3/4 is
24bit, and that the IAR and EOIR registers of the Gic CPU interface are
32 bit; the typedef HARDWARE_INTERRUPT_SOURCE is defined as UINTN in
EmbeddedPkg\Include\Protocol\HardwareInterrupt.h
Therefore, use UINTN for Gic Interrupt variables and use appropriate
typecasts wherever needed.
Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
The CPU Interface Identification Register (GICC_IIDR) is a 32-bit
register. Since ArmGicGetInterfaceIdentification () returns the value
read from the GICC_IIDR register, update the return type for this
function to UINT32.
Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
According to edk2 coding standard specification, Non-Boolean comparisons
must use a compare operator (==, !=, >, < >=, <=). See Section 5.7.2.1
at https://edk2-docs.gitbook.io/
edk-ii-c-coding-standards-specification/5_source_files/ 57_c_programming
Therefore, fix the comparison in ArmGicEnableDistributor()
Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>