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This patch enables BL2 to execute at the highest exception level
without any dependancy on TF BL1. This enables platforms which already
have a non-TF Boot ROM to directly load and execute BL2 and subsequent BL
stages without need for BL1.  This is not currently possible because
BL2 executes at S-EL1 and cannot jump straight to EL3.

Change-Id: Ief1efca4598560b1b8c8e61fbe26d1f44e929d69
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>

This patch adds a new build option, ENABLE_SVE_FOR_NS, which when set
to one EL3 will check to see if the Scalable Vector Extension (SVE) is
implemented when entering and exiting the Non-secure world.

If SVE is implemented, EL3 will do the following:

- Entry to Non-secure world: SIMD, FP and SVE functionality is enabled.

- Exit from Non-secure world: SIMD, FP and SVE functionality is
  disabled. As SIMD and FP registers are part of the SVE Z-registers
  then any use of SIMD / FP functionality would corrupt the SVE
  registers.

The build option default is 1. The SVE functionality is only supported
on AArch64 and so the build option is set to zero when the target
archiecture is AArch32.

This build option is not compatible with the CTX_INCLUDE_FPREGS - an
assert will be raised on platforms where SVE is implemented and both
ENABLE_SVE_FOR_NS and CTX_INCLUDE_FPREGS are set to 1.

Also note this change prevents secure world use of FP&SIMD registers on
SVE-enabled platforms. Existing Secure-EL1 Payloads will not work on
such platforms unless ENABLE_SVE_FOR_NS is set to 0.

Additionally, on the first entry into the Non-secure world the SVE
functionality is enabled and the SVE Z-register length is set to the
maximum size allowed by the architecture. This includes the use case
where EL2 is implemented but not used.

Change-Id: Ie2d733ddaba0b9bef1d7c9765503155188fe7dae
Signed-off-by: David Cunado <david.cunado@arm.com>

This patch fixes a couple of issues for AArch32 builds on ARM reference
platforms :

1. The arm_def.h previously defined the same BL32_BASE value for AArch64 and
   AArch32 build. Since BL31 is not present in AArch32 mode, this meant that
   the BL31 memory is empty when built for AArch32. Hence this patch allocates
   BL32 to the memory region occupied by BL31 for AArch32 builds.

   As a side-effect of this change, the ARM_TSP_RAM_LOCATION macro cannot
   be used to control the load address of BL32 in AArch32 mode which was
   never the intention of the macro anyway.

2. A static assert is added to sp_min linker script to check that the progbits
   are within the bounds expected when overlaid with other images.

3. Fix specifying `SPD` when building Juno for AArch32 mode. Due to the quirks
   involved when building Juno for AArch32 mode, the build option SPD needed to
   specifed. This patch corrects this and also updates the documentation in the
   user-guide.

4. Exclude BL31 from the build and FIP when building Juno for AArch32 mode. As
   a result the previous assumption that BL31 must be always present is removed
   and the certificates for BL31 is only generated if `NEED_BL31` is defined.

Change-Id: I1c39bbc0abd2be8fbe9f2dea2e9cb4e3e3e436a8
Signed-off-by: Soby Mathew <soby.mathew@arm.com>

The Cortex A75 has 5 AMU counters.  The first three counters are fixed
and the remaining two are programmable.

A new build option is introduced, `ENABLE_AMU`.  When set, the fixed
counters will be enabled for use by lower ELs.  The programmable
counters are currently disabled.

Change-Id: I4bd5208799bb9ed7d2596e8b0bfc87abbbe18740
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

This patch replaces the macro ASM_ASSERTION with the macro
ENABLE_ASSERTIONS in ARM Cortex-A53/57/72 MPCore Processor
related files. There is build error when ASM_ASSERTION is set
to 1 and ENABLE_ASSERTIONS is set to 0 because function
asm_assert in common/aarch32/debug.S is defined in the macro
ENABLE_ASSERTIONS but is called with the macro ASM_ASSERTION.

There is also the indication to use ENABLE_ASSERTIONS but not
ASM_ASSERTION in the Makefile.
Signed-off-by: Matt Ma <matt.ma@spreadtrum.com>

The flag support the following values:
    - sha256 (default)
    - sha384
    - sha512

Change-Id: I7a49d858c361e993949cf6ada0a86575c3291066
Signed-off-by: Qixiang Xu <qixiang.xu@arm.com>

It is not possible to detect at compile-time whether support for an
optional extension such as SPE should be enabled based on the
ARM_ARCH_MINOR build option value.  Therefore SPE is now enabled by
default.

Change-Id: I670db164366aa78a7095de70a0962f7c0328ab7c
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

The implementation currently supports only interrupt-based SDEI events,
and supports all interfaces as defined by SDEI specification version
1.0 [1].

Introduce the build option SDEI_SUPPORT to include SDEI dispatcher in
BL31.

Update user guide and porting guide. SDEI documentation to follow.

[1] http://infocenter.arm.com/help/topic/com.arm.doc.den0054a/ARM_DEN0054A_Software_Delegated_Exception_Interface.pdf



Change-Id: I758b733084e4ea3b27ac77d0259705565842241a
Co-authored-by: Yousuf A <yousuf.sait@arm.com>
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

EHF is a framework that allows dispatching of EL3 interrupts to their
respective handlers in EL3.

This framework facilitates the firmware-first error handling policy in
which asynchronous exceptions may be routed to EL3. Such exceptions may
be handed over to respective exception handlers. Individual handlers
might further delegate exception handling to lower ELs.

The framework associates the delegated execution to lower ELs with a
priority value. For interrupts, this corresponds to the priorities
programmed in GIC; for other types of exceptions, viz. SErrors or
Synchronous External Aborts, individual dispatchers shall explicitly
associate delegation to a secure priority. In order to prevent lower
priority interrupts from preempting higher priority execution, the
framework provides helpers to control preemption by virtue of
programming Priority Mask register in the interrupt controller.

This commit allows for handling interrupts targeted at EL3. Exception
handlers own interrupts by assigning them a range of secure priorities,
and registering handlers for each priority range it owns.

Support for exception handling in BL31 image is enabled by setting the
build option EL3_EXCEPTION_HANDLING=1.

Documentation to follow.

NOTE: The framework assumes the priority scheme supported by platform
interrupt controller is compliant with that of ARM GIC architecture (v2
or later).

Change-Id: I7224337e4cea47c6ca7d7a4ca22a3716939f7e42
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

A Secure Partition is a software execution environment instantiated in
S-EL0 that can be used to implement simple management and security
services. Since S-EL0 is an unprivileged exception level, a Secure
Partition relies on privileged firmware e.g. ARM Trusted Firmware to be
granted access to system and processor resources. Essentially, it is a
software sandbox that runs under the control of privileged software in
the Secure World and accesses the following system resources:

- Memory and device regions in the system address map.
- PE system registers.
- A range of asynchronous exceptions e.g. interrupts.
- A range of synchronous exceptions e.g. SMC function identifiers.

A Secure Partition enables privileged firmware to implement only the
absolutely essential secure services in EL3 and instantiate the rest in
a partition. Since the partition executes in S-EL0, its implementation
cannot be overly complex.

The component in ARM Trusted Firmware responsible for managing a Secure
Partition is called the Secure Partition Manager (SPM). The SPM is
responsible for the following:

- Validating and allocating resources requested by a Secure Partition.
- Implementing a well defined interface that is used for initialising a
  Secure Partition.
- Implementing a well defined interface that is used by the normal world
  and other secure services for accessing the services exported by a
  Secure Partition.
- Implementing a well defined interface that is used by a Secure
  Partition to fulfil service requests.
- Instantiating the software execution environment required by a Secure
  Partition to fulfil a service request.

Change-Id: I6f7862d6bba8732db5b73f54e789d717a35e802f
Co-authored-by: Douglas Raillard <douglas.raillard@arm.com>
Co-authored-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
Co-authored-by: Achin Gupta <achin.gupta@arm.com>
Co-authored-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

If ARMv7 based platform does not set ARM_CORTEX_Ax=yes, platform
shall define ARMV7_SUPPORTS_GENERIC_TIMER to enable generic timer
support.
Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>

ARMv7-A Virtualization extensions brings new instructions and resources
that were supported by later architectures. Reference ARM ARM Issue C.c
[DDI0406C_C].

ERET and extended MSR/MRS instructions, as specified in [DDI0406C_C] in
ID_PFR1 description of bits[15:12] (Virtualization Extensions):
 A value of 0b0001 implies implementation of the HVC, ERET, MRS
 (Banked register), and MSR (Banked register) instructions. The ID_ISARs
 do not identify whether these instructions are implemented.

UDIV/SDIV were introduced with the Virtualization extensions, even if
not strictly related to the virtualization extensions.

If ARMv7 based platform does not set ARM_CORTEX_Ax=yes, platform
shall define ARMV7_SUPPORTS_VIRTUALIZATION to enable virtualization
extension related resources.
Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>

ARCH_SUPPORTS_LARGE_PAGE_ADDRESSING allows build environment to
handle specific case when target ARMv7 core only supports 32bit MMU
descriptor mode.

If ARMv7 based platform does not set ARM_CORTEX_Ax=yes, platform
shall define ARMV7_SUPPORTS_LARGE_PAGE_ADDRESSING to enable
large page addressing support.
Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>

External build environment shall sets directive ARM_ARCH_MAJOR to 7
to specify a target ARMv7-A core.

As ARM-TF expects AARCH to be set, ARM_ARCH_MAJOR==7 mandates
AARCH=aarch32.

The toolchain target architecture/cpu is delegated after the platform
configuration is parsed. Platform shall define target core through
ARM_CORTEX_A<x>=yes, <x> being 5, 7, 9, 12, 15 and/or 17.

Platform can bypass ARM_CORTEX_A<x>=yes directive and provide straight
the toolchain target directive through MARCH32_DIRECTIVE.
Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>

Some platforms (for ex. UniPhier) want to create files in the very
top of the build directory.  Add ${BUILD_PLAT} so such files can
depend on it.

Make existing directory targets depend on ${BUILD_PLAT} because
they are sub-directories of ${BUILD_PLAT}.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

The back end GIC driver converts and assigns the interrupt type to
suitable group.

For GICv2, a build option GICV2_G0_FOR_EL3 is introduced, which
determines to which type Group 0 interrupts maps to.

 - When the build option is set 0 (the default), Group 0 interrupts are
   meant for Secure EL1. This is presently the case.

 - Otherwise, Group 0 interrupts are meant for EL3. This means the SPD
   will have to synchronously hand over the interrupt to Secure EL1.

The query API allows the platform to query whether the platform supports
interrupts of a given type.

API documentation updated.

Change-Id: I60fdb4053ffe0bd006b3b20914914ebd311fc858
Co-authored-by: Yousuf A <yousuf.sait@arm.com>
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

This is a revamp of the original approach in:
https://github.com/ARM-software/arm-trusted-firmware/pull/747



Current build system has no means to automatically generate dtbs from
dts, instead, stores the dtbs in the fdts/ folder. While this makes
perfect sense for many reference platforms, this becomes a minor
breakage in development flow for newer platforms.

However, this can be solved by providing a rule for the dtbs while
building the ATF binaries by purely describing which dts sources we
need.

For example, with this change, we will now be able to describe the
dtbs we need for the platform in the corresponding platform.mk file:
FDT_SOURCES += fdts/abc.dts

This should be able to generate the abc.dtb appropriately.

Since device trees are specification of hardware, we don't tie the rule
to any specific BL, instead a generic rule is introduced.

Further, this approach allows us to generate appropriate dtbs which may be
need to be regenerated when a common dtsi gets updated, by just
restricting changes to the dtsi alone, instead of synchronizing all the
dtbs as well.

If dtc is not available in default paths, but is available in an
alternate location, it can be chosen by overriding the DTC variable
such as 'make DTC=~/dtc/dtc ....`

NOTE: dtbs are built only with the explicit make dtbs command. The rule
is only available if the platform defines a FDT_SOURCES variable.
Signed-off-by: Benjamin Fair <b-fair@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>

The `KEY_ALG` variable is used to select the algorithm for key
generation by `cert_create` tool for signing the certificates. This
variable was previously undocumented and did not have a global default
value. This patch corrects this and also adds changes to derive the
value of `TF_MBEDTLS_KEY_ALG` based on `KEY_ALG` if it not set by the
platform. The corresponding assignment of these variables are also now
removed from the `arm_common.mk` makefile.
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
Change-Id: I78e2d6f4fc04ed5ad35ce2266118afb63127a5a4

Since Trusted OS firmware may have extra images, need to
assign new uuid and image id for them.
The TBBR chain of trust has been extended to add support
for the new images within the existing Trusted OS firmware
content certificate.

Change-Id: I678dac7ba1137e85c5779b05e0c4331134c10e06
Signed-off-by: Summer Qin <summer.qin@arm.com>

The current build system and driver requires the CCI product to be
specified at build time. The device constraints can be determined at run
time from its ID registers, obviating the need for specifying them
ahead.

This patch adds changes to identify and validate CCI at run time. Some
global variables are renamed to be in line with the rest of the code
base.

The build option ARM_CCI_PRODUCT_ID is now removed, and user guide is
updated.

Change-Id: Ibb765e349d3bc95ff3eb9a64bde1207ab710a93d
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

This patch defines the variable `LDLIBS` which allows external
libraries to be specified to 'ld' to enable it to link the
libraries.

Change-Id: I02a490eca1074063d00153ccb0ee974ef8859a0e
Signed-off-by: Soby Mathew <soby.mathew@arm.com>

Use TF_LDFLAGS from the Makefiles, and still append LDFLAGS as well to
the compiler's invocation. This allows passing extra options from the
make command line using LDFLAGS.

Document new LDFLAGS Makefile option.

Change-Id: I88c5ac26ca12ac2b2d60a6f150ae027639991f27
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>

SPE is only supported in non-secure state.  Accesses to SPE specific
registers from SEL1 will trap to EL3.  During a world switch, before
`TTBR` is modified the SPE profiling buffers are drained.  This is to
avoid a potential invalid memory access in SEL1.

SPE is architecturally specified only for AArch64.

Change-Id: I04a96427d9f9d586c331913d815fdc726855f6b0
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>

It doesn't make sense to use the `-pedantic` flag when building the
Trusted Firmware as we use GNU extensions and so our code is not
fully ISO C compliant. This flag only makes sense if the code intends to
be ISO C compliant.

Change-Id: I6273564112759ff57f03b273f5349733a5f38aef
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Platforms aligned with TBBR are supposed to use their own OIDs, but
defining the same macros with different OIDs does not provide any
value (at least technically).

For easier use of TBBR, this commit allows platforms to reuse the OIDs
obtained by ARM Ltd.  This will be useful for non-ARM vendors that
do not need their own extension fields in their certificate files.

The OIDs of ARM Ltd. have been moved to include/tools_share/tbbr_oid.h

Platforms can include <tbbr_oid.h> instead of <platform_oid.h> by
defining USE_TBBR_DEFS as 1.  USE_TBBR_DEFS is 0 by default to keep the
backward compatibility.

For clarification, I inserted a blank line between headers from the
include/ directory (#include <...>) and ones from a local directory
(#include "..." ).
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

The current assert_boolean does not work with variables assigned with
'=' flavor instead of ':='.

For example,

 FOO = $(BAR)
 BAR := 1

Here, $(value FOO) is evaluated to $(BAR), not 1.  This is not what
we expect.  While I am here, I simplified the implementation.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

This patch adds `TRUSTED_BOARD_BOOT` support for AArch32 mode.

To build this patch the "mbedtls/include/mbedtls/bignum.h"
needs to be modified to remove `#define MBEDTLS_HAVE_UDBL`
when `MBEDTLS_HAVE_INT32` is defined. This is a workaround
for "https://github.com/ARMmbed/mbedtls/issues/708

"

NOTE: TBBR support on Juno AArch32 is not currently supported.

Change-Id: I86d80e30b9139adc4d9663f112801ece42deafcf
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>
Co-Authored-By: Yatharth Kochar <yatharth.kochar@arm.com>

To make software license auditing simpler, use SPDX[0] license
identifiers instead of duplicating the license text in every file.

NOTE: Files that have been imported by FreeBSD have not been modified.

[0]: https://spdx.org/



Change-Id: I80a00e1f641b8cc075ca5a95b10607ed9ed8761a
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>

Some recent changes have added direct use of the echo command without
parameters.  This fails on a Windows shell, because echo without
parameters reports the mode ("ECHO is on").
This is corrected using the ECHO_BLANK_LINE macro already provided
for that purpose.

Change-Id: I5fd7192861b4496f6f46b4f096e80a752cd135d6
Signed-off-by: Evan Lloyd <evan.lloyd@arm.com>

2 problems were found, but are in one change to avoid submitting a patch
that might fail to build. The problems were:
1.  The macro MAKE_PREREQ_DIR has a minor bug, in that it is capable of
    generating recursive dependencies.
2.  The inclusion of BUILD_DIR in TEMP_OBJ_DIRS left no explicit
    dependency, BUILD_DIR might not exist when subdirectories are
    created by a thread on another CPU.

This fix corrects these with the following changes:
1.  MAKE_PREREQ_DIR does nothing for a direct self dependency.
2.  BUILD_DIR is built using MAKE_PREREQ_DIR.
3.  BUILD_DIR is an explicit prerequisite of all OBJ_DIRS.

Change-Id: I938cddea4a006df225c02a47b9cf759212f27fb7
Signed-off-by: Evan Lloyd <evan.lloyd@arm.com>

This patch introduces a build option to enable D-cache early on the CPU
after warm boot. This is applicable for platforms which do not require
interconnect programming to enable cache coherency (eg: single cluster
platforms). If this option is enabled, then warm boot path enables
D-caches immediately after enabling MMU.

Fixes ARM-Software/tf-issues#456

Change-Id: I44c8787d116d7217837ced3bcf0b1d3441c8d80e
Signed-off-by: Soby Mathew <soby.mathew@arm.com>

Introduce new build option ENABLE_STACK_PROTECTOR. It enables
compilation of all BL images with one of the GCC -fstack-protector-*
options.

A new platform function plat_get_stack_protector_canary() is introduced.
It returns a value that is used to initialize the canary for stack
corruption detection. Returning a random value will prevent an attacker
from predicting the value and greatly increase the effectiveness of the
protection.

A message is printed at the ERROR level when a stack corruption is
detected.

To be effective, the global data must be stored at an address
lower than the base of the stacks. Failure to do so would allow an
attacker to overwrite the canary as part of an attack which would void
the protection.

FVP implementation of plat_get_stack_protector_canary is weak as
there is no real source of entropy on the FVP. It therefore relies on a
timer's value, which could be predictable.

Change-Id: Icaaee96392733b721fa7c86a81d03660d3c1bc06
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>

The boolean build option HW_ASSISTED_COHERENCY is introduced to enable
various optimizations in ARM Trusted Software, when built for such
systems. It's set to 0 by default.

Change-Id: I638390da6e1718fe024dcf5b402e07084f1eb014
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

The ARMv8v.1 architecture extension has introduced support for far
atomics, which includes compare-and-swap. Compare and Swap instruction
is only available for AArch64.

Introduce build options to choose the architecture versions to target
ARM Trusted Firmware:

  - ARM_ARCH_MAJOR: selects the major version of target ARM
    Architecture. Default value is 8.

  - ARM_ARCH_MINOR: selects the minor version of target ARM
    Architecture. Default value is 0.

When:

  (ARM_ARCH_MAJOR > 8) || ((ARM_ARCH_MAJOR == 8) && (ARM_ARCH_MINOR >= 1)),

for AArch64, Compare and Swap instruction is used to implement spin
locks. Otherwise, the implementation falls back to using
load-/store-exclusive instructions.

Update user guide, and introduce a section in Firmware Design guide to
summarize support for features introduced in ARMv8 Architecture
Extensions.

Change-Id: I73096a0039502f7aef9ec6ab3ae36680da033f16
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

The current fiptool packs all the images without any padding between
them.  So, the offset to each image has no alignment.  This is not
efficient, for example, when the FIP is read from a block-oriented
device.

For example, (e)MMC is accessed by block-addressing.  The block size
is 512 byte.  So, the best case is each image is aligned by 512 byte
since the DMA engine can transfer the whole of the image to its load
address directly.  The worst case is the offset does not have even
DMA-capable alignment (this is where we stand now).  In this case,
we need to transfer every block to a bounce buffer, then do memcpy()
from the bounce buffer to our final destination.  At least, this
should work with the abstraction by the block I/O layer, but the
CPU-intervention for the whole data transfer makes it really slow.

This commit adds a new option --align to the fiptool.  This option,
if given, requests the tool to align each component in the FIP file
by the specified byte.  Also, add a new Make option FIP_ALIGN for
easier access to this feature; users can give something like
FIP_ALIGN=512 from the command line, or add "FIP_ALIGN := 512" to
their platform.mk file.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Append . then strip /. seems clumsy.  Just use $(patsubst %/,%, ).
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Soren reports build fails if -j option is given:

  $ make -j16 CROSS_COMPILE=aarch64-linux-gnu-
  Building fvp
  make: *** No rule to make target 'build/fvp/release/bl1/',
                    needed by 'build/fvp/release/bl1/bl1.ld'.  Stop.
  make: *** Waiting for unfinished jobs....

The cause of the failure is that $(dir ) leaves a trailing / on the
directory names.   It must be ripped off to let Make create the
directory.

There are some ways to fix the issue.  Here, I chose to make MAKE_LD
look like MAKE_C and MAKE_S because bl*_dirs seems the central place
of making directories.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reported-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Tested-by: Soren Brinkmann <soren.brinkmann@xilinx.com>

This adds a phony target for each dependency other than the main
file, causing each to depend on nothing.

Without this, the incremental build will fail when a header file
is removed.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Currently, .d files are generated before any objects are built.
So, IS_ANYTHING_TO_BUILD flag is needed to avoid such processing for
non-build targets.

There is a cleverer way; just create a .d file simultaneously when
the corresponding object is created.  No need to have separate rules
for .d files.

This commit will also fix a bug; -D$(IMAGE) is defined for $(OBJ),
but not for $(PREREQUISITES).  So, .d files are generated with
different macro sets from those for .o files, then wrong .d files
are generated.

For example, in lib/cpus/aarch64/cpu_helpers.S

  #if IMAGE_BL31
  #include <cpu_data.h>
  #endif

<cpu_data.h> is parsed for the object when built for BL31, but the
.d file does not pick up that dependency.

With this commit, the compiler will generate .o and .d at the same
time, guaranteeing they are generated under the same circumstances.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Using AS for pre-processing looks a bit weird, and some assembly
specific options are given for nothing.  Rather, use CPP.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>