Commit Graph

230 Commits

Author SHA1 Message Date
Qixiang Xu 9a3088a5f5 tbbr: Add build flag HASH_ALG to let the user to select the SHA
The flag support the following values:
    - sha256 (default)
    - sha384
    - sha512

Change-Id: I7a49d858c361e993949cf6ada0a86575c3291066
Signed-off-by: Qixiang Xu <qixiang.xu@arm.com>
2017-11-21 14:16:18 +08:00
Jeenu Viswambharan 385f1dbb29 GIC: Fix Group 0 enabling
At present, the GIC drivers enable Group 0 interrupts only if there are
Secure SPIs listed in the interrupt properties/list. This means that,
even if there are Group 0 SGIs/PPIs configured, the group remained
disabled in the absence of a Group 0 SPI.

Modify both GICv2 and GICv3 SGI/PPI configuration to enable Group 0 when
corresponding SGIs/PPIs are present.

Change-Id: Id123e8aaee0c22b476eebe3800340906d83bbc6d
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
2017-11-13 07:49:30 +00:00
Jeenu Viswambharan 058efeef98 GICv2: Fix populating PE target data
This patch brings in the following fixes:

  - The per-PE target data initialized during power up needs to be
    flushed so as to be visible to other PEs.

  - Setup per-PE target data for the primary PE as well. At present,
    this was only setup for secondary PEs when they were powered on.

Change-Id: Ibe3a57c14864e37b2326dd7ab321a5c7bf80e8af
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
2017-11-13 07:49:30 +00:00
Jeenu Viswambharan c639e8ebee GIC: Allow specifying interrupt properties
The GIC driver initialization currently allows an array of interrupts to
be configured as secure. Future use cases would require more interrupt
configuration other than just security, such as priority.

This patch introduces a new interrupt property array as part of both
GICv2 and GICv3 driver data. The platform can populate the array with
interrupt numbers and respective properties. The corresponding driver
initialization iterates through the array, and applies interrupt
configuration as required.

This capability, and the current way of supplying array (or arrays, in
case of GICv3) of secure interrupts, are however mutually exclusive.
Henceforth, the platform should supply either:

  - A list of interrupts to be mapped as secure (the current way).
    Platforms that do this will continue working as they were. With this
    patch, this scheme is deprecated.

  - A list of interrupt properties (properties include interrupt group).
    Individual interrupt properties are specified via. descriptors of
    type 'interrupt_prop_desc_t', which can be populated with the macro
    INTR_PROP_DESC().

A run time assert checks that the platform doesn't specify both.

Henceforth the old scheme of providing list of secure interrupts is
deprecated. When built with ERROR_DEPRECATED=1, GIC drivers will require
that the interrupt properties are supplied instead of an array of secure
interrupts.

Add a section to firmware design about configuring secure interrupts.

Fixes ARM-software/tf-issues#262

Change-Id: I8eec29e72eb69dbb6bce77879febf32c95376942
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
2017-10-16 16:50:02 +01:00
Jeenu Viswambharan 2296610696 GIC: Add helpers to set interrupt configuration
The helpers perform read-modify-write on GIC*_ICFGR registers, but don't
serialise callers. Any serialisation must be taken care of by the
callers.

Change-Id: I71995f82ff2c7f70d37af0ede30d6ee18682fd3f
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
2017-10-16 16:50:02 +01:00
Jeenu Viswambharan d55a445069 GIC: Add API to set priority mask
API documentation updated.

Change-Id: I40feec1fe67a960d035061b54dd55610bc34ce1d
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
2017-10-16 16:50:02 +01:00
Jeenu Viswambharan a2816a1644 GIC: Add API to set/clear interrupt pending
API documentation updated.

Change-Id: I14e33cfc7dfa93257c82d76fae186b17a1b6d266
Co-authored-by: Yousuf A <yousuf.sait@arm.com>
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
2017-10-16 16:50:02 +01:00
Jeenu Viswambharan fc529fee72 GIC: Add API to set interrupt routing
SPIs can be routed to either a specific PE, or to any one of all
available PEs.

API documentation updated.

Change-Id: I28675f634568aaf4ea1aa8aa7ebf25b419a963ed
Co-authored-by: Yousuf A <yousuf.sait@arm.com>
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
2017-10-16 16:50:02 +01:00
Jeenu Viswambharan 8db978b5a8 GIC: Add API to raise secure SGI
API documentation updated.

Change-Id: I129725059299af6cc612bafa8d74817f779d7c4f
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
2017-10-16 16:50:02 +01:00
Jeenu Viswambharan 74dce7fa6e GIC: Add APIs to set interrupt type and query support
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>
2017-10-16 16:50:01 +01:00
Jeenu Viswambharan f3a866004e GIC: Add API to set interrupt priority
API documentation updated.

Change-Id: Ib700eb1b8ca65503aeed0ac4ce0e7b934df67ff9
Co-authored-by: Yousuf A <yousuf.sait@arm.com>
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
2017-10-16 16:50:01 +01:00
Jeenu Viswambharan 979225f4ee GIC: Add APIs to enable and disable interrupt
API documentation updated.

Change-Id: Ice7511f8df5356851001d2f7dc2a46cfe318f9ba
Co-authored-by: Yousuf A <yousuf.sait@arm.com>
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
2017-10-16 16:50:01 +01:00
Jeenu Viswambharan cbd3f3706d GIC: Add API to get interrupt active status
API documentation updated.

Change-Id: I6d61785af0d5330930c709de971a904dc7c3516c
Co-authored-by: Yousuf A <yousuf.sait@arm.com>
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
2017-10-16 16:50:01 +01:00
Jeenu Viswambharan fa9db4230a GICv2: Add driver API to set PE target mask
The PE target mask is used to translate linear PE index (returned by
platform core position) to a bit mask used when targeting interrupts to
a PE, viz. when raising SGIs and routing SPIs.

The platform shall:

  - Populate the driver data with a pointer to array that's to contain
    per-PE target masks.

  - Invoke the new driver API 'gicv2_set_pe_target_mask()' during
    per-CPU initialization so that the driver populates the target mask
    for that CPU.

Platforms that don't intend to target interrupts or raise SGIs need not
populate this.

Change-Id: Ic0db54da86915e9dccd82fff51479bc3c1fdc968
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
2017-10-16 16:50:01 +01:00
Jeenu Viswambharan eb68ea9b10 GIC: Add API to get running priority
Document the API in separate platform interrupt controller API document.

Change-Id: If18f208e10a8a243f5c59d226fcf48e985941949
Co-authored-by: Yousuf A <yousuf.sait@arm.com>
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
2017-10-16 16:50:01 +01:00
Soby Mathew c1bbeb5fab Fix assertion in GIC ITS helper
This patch fixes an assertion check in the GICv3 ITS helper function.

Change-Id: I75f50d7bf6d87c12c6e24a07c9a9889e5facf4a5
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
2017-10-06 18:12:37 +01:00
Soby Mathew b258278eec GICv3: ITS architectural save and restore helpers
This patch adds functions to save and restore GICv3 ITS registers during
system suspend. Please note that the power management of GIC ITS is
implementation defined. These functions only implements the
architectural part of the ITS power management and they do not restore
memory structures or register content required to support ITS. Even if
the ITS implementation stores structures in memory, an implementation
defined power down sequence is likely to be required to flush some
internal ITS caches to memory. If such implementation defined sequence
is not followed, the platform must ensure that the ITS is not power
gated during system suspend.

Change-Id: I5f31e5541975aa7dcaab69b0b7f67583c0e27678
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>
2017-10-05 16:47:53 +01:00
Soby Mathew ebf1ca10e4 GICv3: add functions for save and restore
During system suspend, the GICv3 Distributor and Redistributor context
can be lost due to power gating of the system power domain. This means
that the GICv3 context needs to be saved prior to system suspend and
restored on wakeup. Currently the consensus is that the Firmware should
be in charge of this. See tf-issues#464 for more details.

This patch introduces helper APIs in the GICv3 driver to save and
restore the Distributor and Redistributor contexts. The GICv3 ITS
context is not considered in this patch because the specification says
that the details of ITS power management is implementation-defined.
These APIs are expected to be appropriately invoked by the platform
layer during system suspend.

Fixes ARM-software/tf-issues#464

Change-Id: Iebb9c6770ab8c4d522546f161fa402d2fe02ec00
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>
2017-10-05 16:47:53 +01:00
Douglas Raillard a64b4e626e GICv3: turn some macros into inline functions
Tidy up the code a bit by turning some macros into inline functions
which allows to remove the do/while(0) idiom and backslashes at the end
of the line.

Change-Id: Ie41a4ea4a4da507f7b925247b53e85019101d717
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>
2017-10-05 16:47:53 +01:00
Douglas Raillard b50bdceadf GICv3: Fix gic600.c indentation
Reindent the file using tabs as the mix of spaces and tabs confuses some
editors and leads them to use spaces instead of tabs for new code
although the coding style mandates tabs.

Change-Id: I87fa4a5d368a048340054b9b3622325f3f7befba
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>
2017-10-05 16:47:53 +01:00
davidcunado-arm b8fa2ed562 Merge pull request #1107 from geesun/qx/add_ecdsa_support
Add support for TBBR using ECDSA keys in ARM platforms
2017-10-02 15:03:16 +01:00
Qixiang Xu dcbf3932fd Dynamic selection of ECDSA or RSA
Add new option rsa+ecdsa for TF_MBEDTLS_KEY_ALG, which selects
rsa or ecdsa depending on the certificate used.

Change-Id: I08d9e99bdbba361ed2ec5624248dc382c750ad47
Signed-off-by: Qixiang Xu <qixiang.xu@arm.com>
2017-09-22 17:42:40 +08:00
Qixiang Xu 9db9c65a11 Add support for TBBR using ECDSA keys in ARM platforms
- fixed compile error when KEY_ALG=ecdsa
    - add new option ecdsa for TF_MBEDTLS_KEY_ALG
    - add new option devel_ecdsa for ARM_ROTPK_LOCATION
    - add ecdsa key at plat/arm/board/common/rotpk/
    - reduce the mbedtls heap memory size to 13k

Change-Id: I3f7a6170af93fdbaaa7bf2fffb4680a9f6113c13
Signed-off-by: Qixiang Xu <qixiang.xu@arm.com>
2017-09-22 09:48:36 +08:00
Antonio Nino Diaz e47ac1fd63 Fix type of `unsigned long` constants
The type `unsigned long` is 32 bit wide in AArch32, but 64 bit wide in
AArch64. This is inconsistent and that's why we avoid using it as per
the Coding Guidelines. This patch changes all `UL` occurrences to `U`
or `ULL` depending on the context so that the size of the constant is
clear.

This problem affected the macro `BIT(nr)`. As long as this macro is used
to fill fields of registers, that's not a problem, since all registers
are 32 bit wide in AArch32 and 64 bit wide in AArch64. However, if the
macro is used to fill the fields of a 64-bit integer, it won't be able
to set the upper 32 bits in AArch32.

By changing the type of this macro to `unsigned long long` the behaviour
is always the same regardless of the architecture, as this type is
64-bit wide in both cases.

Some Tegra platform files have been modified by this patch.

Change-Id: I918264c03e7d691a931f0d1018df25a2796cc221
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2017-09-21 12:03:53 +01:00
Soby Mathew a8eb286ada cert_tool: Support for legacy RSA PKCS#1 v1.5
This patch enables choice of RSA version at run time to be used for
generating signatures by the cert_tool. The RSA PSS as defined in
PKCS#1 v2.1 becomes the default version and this patch enables to specify
the RSA PKCS#1 v1.5 algorithm to `cert_create` through the command line
-a option. Also, the build option `KEY_ALG` can be used to pass this
option from the build system. Please note that RSA PSS is mandated
by Trusted Board Boot requirements (TBBR) and legacy RSA support is
being added for compatibility reasons.

Fixes ARM-Software/tf-issues#499
Change-Id: Ifaa3f2f7c9b43f3d7b3effe2cde76bf6745a5d73
Co-Authored-By: Eleanor Bonnici <Eleanor.bonnici@arm.com>
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
2017-08-31 16:42:11 +01:00
Soby Mathew 2091755c5e Export KEY_ALG as a user build option
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
2017-08-31 16:42:11 +01:00
danh-arm 1a52aca5f6 Merge pull request #1040 from sliai/support-opteed-header
Support opteed header
2017-08-14 16:35:12 +01:00
Summer Qin 71fb396440 Support Trusted OS firmware extra images in TF tools
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>
2017-08-09 18:06:05 +08:00
Jeenu Viswambharan 1154586b71 Add SMMUv3 driver
The driver has only one API: to initialize an SMMUv3 device. This
operates on a device that implements secure state, by invalidating
secure caches and TLBs.

Change-Id: Ief32800419ddf0f1fe38c8f0da8f5ba75c72c826
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
2017-08-01 14:33:47 +01:00
Jeenu Viswambharan e33fd44548 CCI: Adapt for specific product at run time
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>
2017-08-01 14:33:47 +01:00
Isla Mitchell 2a4b4b71ba Fix order of #includes
This fix modifies the order of system includes to meet the ARM TF coding
standard. There are some exceptions in order to retain header groupings,
minimise changes to imported headers, and where there are headers within
the #if and #ifndef statements.

Change-Id: I65085a142ba6a83792b26efb47df1329153f1624
Signed-off-by: Isla Mitchell <isla.mitchell@arm.com>
2017-07-12 14:45:31 +01:00
Soby Mathew fd2b42f4ae Do basic CryptoCell LCS check
This patch implements the basic lifecycle state check when CryptoCell
SBROM is initialized. Currently the check ensures that if the lifecycle
state is Security Disabled (SD), the boot process does not proceed
further.

Change-Id: I5101335453cd3ea413e97bcfb9138a96c05e1aea
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
2017-06-28 15:58:06 +01:00
Soby Mathew 4eb20d99c5 Add CC crypto driver to the Auth module
This patch adds a crypto driver which utilizes the ARM® TrustZone®
CryptoCell-712 to verify signature and hash during Trusted Board Boot. Along
with this driver, the CryptoCell SBROM library is required to successfully
build the BL image. The path to this library is specified via
the `CCSBROM_LIB_PATH` variable. Please note that, mbedTLS is still required
to do the X509 certificate ASN.1 parsing and CryptoCell is only utilized for
signature and hash verification.

Change-Id: If82dfbae0d7772ba1c64839f0b27850c103fe253
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
2017-06-28 15:58:06 +01:00
Etienne Carriere d60e6bae02 io_dummy: correct sparse warnings
Include io_dummy.h header file.
Use static for device_type_dummy function.

Signed-off-by: Yann Gautier <yann.gautier@st.com>
Signed-off-by: Etienne Carriere <etienne.carriere@st.com>
2017-06-23 09:38:15 +02:00
Etienne Carriere 5a8e2aeec4 io_storage: use unsigned int for index
This change avoids warning about type conversion.

Signed-off-by: Yann Gautier <yann.gautier@st.com>
Signed-off-by: Etienne Carriere <etienne.carriere@st.com>
2017-06-23 09:38:13 +02:00
Etienne Carriere 1496b4895e delay_timer: correct sparse issues and warnings
Use NULL instead of 0 where required.
Include headers to have the prototype of the functions.

Signed-off-by: Yann Gautier <yann.gautier@st.com>
Signed-off-by: Etienne Carriere <etienne.carriere@st.com>
2017-06-23 09:38:08 +02:00
Haojian Zhuang 101afa02b7 ufs: fix the and operator
Should use AND (&), not &&.

Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>
2017-06-13 14:33:49 +08:00
davidcunado-arm b91926fd50 Merge pull request #968 from antonio-nino-diaz-arm/an/snprintf-alt
mbedtls: Don't use tf_snprintf if option not defined
2017-06-09 12:03:35 +01:00
Antonio Nino Diaz c46c18c598 mbedtls: Don't use tf_snprintf if option not defined
If `MBEDTLS_PLATFORM_SNPRINTF_ALT` isn't used, the function
`mbedtls_platform_set_snprintf()` isn't defined.

In case a platform uses a different mbed TLS configuration file than
the one provided by the Trusted Firmware, and it doesn't define the
mentioned build option, this will result in a build error.

This patch modifies the initialization code so that
`mbedtls_platform_set_snprintf()` is only used if
`MBEDTLS_PLATFORM_SNPRINTF_ALT` is defined, allowing platforms to use
it or not depending on their needs.

Change-Id: I1d5c86d57e9b2871ba463030bf89210ebec5178e
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2017-06-06 10:54:42 +01:00
danh-arm 47fd7cb0ac Merge pull request #964 from soby-mathew/sm/rsapss_sup
Add support for RSASSAPSS algorithm
2017-06-05 14:45:10 +01:00
Soby Mathew 1001202d24 Add support for RSASSAPSS algorithm in mbedtls crypto driver
This patch adds support for RSASSA-PSS Signature Algorithm for
X509 certificates in mbedtls crypto driver. Now the driver supports
RSA PKCS2_1 standard as mandated by TBBR.

NOTE: With this patch, the PKCS1_5 standard compliant RSA signature
is deprecated.

Change-Id: I9cf6d073370b710cc36a7b374a55ec96c0496461
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
2017-06-05 12:25:26 +01:00
Soby Mathew 38aacad3cb Increase heapsize for mbedtls library
The mbedTLS library requires larger heap memory for verification of RSASSA-PSS
signature in certificates during Trusted Board Boot. This patch increases the
heap memory for the same.

Change-Id: I3c3123d7142b7b7b01463516ec436734895da159
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
2017-06-05 12:23:27 +01:00
Jeenu Viswambharan e1c59ab3f1 Introduce ARM GIC-600 driver
ARM GIC-600 IP complies with ARM GICv3 architecture, but among others,
implements a power control register in the Redistributor frame. This
register must be programmed to mark the frame as powered on, before
accessing other registers in the frame. Rest of initialization sequence
remains the same.

The driver provides APIs for Redistributor power management, and
overrides those in the generic GICv3 driver. The driver data is shared
between generic GICv3 driver and that of GIC-600.

For FVP platform, the GIC-600 driver is chosen when FVP_USE_GIC_DRIVER
is set to FVP_GIC600. Also update user guide.

Change-Id: I321b2360728d69f6d4b0a747b2cfcc3fe5a20d67
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
2017-06-01 11:44:56 +01:00
danh-arm 2bd26faf62 Merge pull request #958 from antonio-nino-diaz-arm/an/mbedtls-heap-size
mbedtls: Define optimized mbed TLS heap size
2017-05-31 16:40:56 +01:00
Antonio Nino Diaz 05fd893ea4 mbedtls: Define optimized mbed TLS heap size
mbed TLS provides the debug API `mbedtls_memory_buffer_alloc_status()`
to analyse the RAM usage of the library.

When RSA is selected as algorithm, the maximum heap usage in FVP and
Juno has been determined empirically to be approximately 5.5 KiB.
However, The default heap size used when RSA is selected is 8 KiB.

This patch reduces the buffer from 8 KiB to 6 KiB so that the BSS
sections of both BL1 and BL2 are 2 KiB smaller when the firmware is
compiled with TBB support.

Change-Id: I43878a4e7af50c97be9c8d027c728c8483f24fbf
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2017-05-31 15:02:32 +01:00
danh-arm 9260f92949 Merge pull request #955 from hzhuang1/ufs
Add ufs stack and designware phy
2017-05-31 14:25:36 +01:00
Haojian Zhuang 7e08084213 drivers: add designware ufs driver
Initialized the designware UFS PHY.

Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>
2017-05-31 11:00:57 +08:00
Haojian Zhuang eb5073f49e drivers: add ufs stack
If UFS device is initialized, we could just make it out of
hibernation by UFS_FLAGS_SKIPINIT. And vendor's dirver is always
focus on PHY setting. We could use UFS driver directly if it
exits from hibernation.

There're eight LUNs in UFS device. The UFS driver only provides
the read/write API with LUN. User could define his own read/write
since user may want to access different LUNs.

Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>
2017-05-31 11:00:38 +08:00
davidcunado-arm 572e141327 Merge pull request #949 from antonio-nino-diaz-arm/an/printf-memory
Reduce code size when building with Trusted Board Boot enabled
2017-05-30 10:56:47 +01:00
Antonio Nino Diaz ab1794f576 mbedtls: Use `tf_snprintf` instead of `snprintf`
The Trusted Firmware uses a subset of the APIs provided by mbed TLS.
This subset internally uses `snprintf`, but the only format specifier
used is '%d', which is supported by `tf_snprintf`.

This patch makes mbed TLS use `tf_snprintf` instead of `snprintf`,
saving 3 KB in both debug and release builds when TBBR is enabled.

Change-Id: I7f992a21015930d7c0f4660e7a28ceefd60b9597
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2017-05-24 10:47:05 +01:00