xlat: Add support for EL0 and EL1 mappings ...

This patch introduces the ability of the xlat tables library to manage
EL0 and EL1 mappings from a higher exception level.

Attributes MT_USER and MT_PRIVILEGED have been added to allow the user
specify the target EL in the translation regime EL1&0.

REGISTER_XLAT_CONTEXT2 macro is introduced to allow creating a
xlat_ctx_t that targets a given translation regime (EL1&0 or EL3).

A new member is added to xlat_ctx_t to represent the translation regime
the xlat_ctx_t manages. The execute_never mask member is removed as it
is computed from existing information.

Change-Id: I95e14abc3371d7a6d6a358cc54c688aa9975c110
Co-authored-by: Douglas Raillard <douglas.raillard@arm.com>
Co-authored-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
Co-authored-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

xlat: Introduce function xlat_arch_tlbi_va_regime() ...

Introduce a variant of the TLB invalidation helper function that
allows the targeted translation regime to be specified, rather than
defaulting to the current one.

This new function is useful in the context of EL3 software managing
translation tables for the S-EL1&0 translation regime, as then it
might need to invalidate S-EL1&0 TLB entries rather than EL3 ones.

Define a new enumeration to be able to represent translation regimes in
the xlat tables library.

Change-Id: Ibe4438dbea2d7a6e7470bfb68ff805d8bf6b07e5
Co-authored-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
Co-authored-by: Douglas Raillard <douglas.raillard@arm.com>
Co-authored-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

xlat: Always compile TLB invalidation functions ...

TLB invalidation functions used to be conditionally compiled in.
They were enabled only when using the dynamic mapping feature.
because only then would we need to modify page tables on the fly.

Actually there are other use cases where invalidating TLBs is required.
When changing memory attributes in existing translation descriptors for
example. These other use cases do not necessarily depend on the dynamic
mapping feature.

This patch removes this dependency and always compile TLB invalidation
functions in. If they're not used, they will be removed from the binary
at link-time anyway so there's no consequence on the memory footprint
if these functions are not called.

Change-Id: I1c33764ae900eb00073ee23b7d0d53d4efa4dd21
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>

Set TCR_EL1.EPD1 bit to 1 ...

In the S-EL1&0 translation regime we aren't using the higher VA range,
whose translation table base address is held in TTBR1_EL1. The bit
TCR_EL1.EPD1 can be used to disable translations using TTBR1_EL1, but
the code wasn't setting it to 1. Additionally, other fields in TCR1_EL1
associated with the higher VA range (TBI1, TG1, SH1, ORGN1, IRGN1 and
A1) weren't set correctly as they were left as 0. In particular, 0 is a
reserved value for TG1. Also, TBBR1_EL1 was not explicitly set and its
reset value is UNKNOWN.

Therefore memory accesses to the higher VA range would result in
unpredictable behaviour as a translation table walk would be attempted
using an UNKNOWN value in TTBR1_EL1.

On the FVP and Juno platforms accessing the higher VA range resulted in
a translation fault, but this may not always be the case on all
platforms.

This patch sets the bit TCR_EL1.EPD1 to 1 so that any kind of
unpredictable behaviour is prevented.

This bug only affects the AArch64 version of the code, the AArch32
version sets this bit to 1 as expected.

Change-Id: I481c000deda5bc33a475631301767b9e0474a303
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Enable CnP bit for ARMv8.2 CPUs ...

This patch enables the CnP (Common not Private) bit for secure page
tables so that multiple PEs in the same Inner Shareable domain can use
the same translation table entries for a given stage of translation in
a particular translation regime. This only takes effect when ARM
Trusted Firmware is built with ARM_ARCH_MINOR >= 2.

ARM Trusted Firmware Design has been updated to include a description
of this feature usage.

Change-Id: I698305f047400119aa1900d34c65368022e410b8
Signed-off-by: Isla Mitchell <isla.mitchell@arm.com>

xlat lib: Fix some types ...

Fix the type length and signedness of some of the constants and
variables used in the translation table library.

This patch supersedes Pull Request #1018:
https://github.com/ARM-software/arm-trusted-firmware/pull/1018

Change-Id: Ibd45faf7a4fb428a0bf71c752551d35800212fb2
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>

xlat lib v2: Remove hard-coded virtual address space size ...

Previous patches have made it possible to specify the physical and
virtual address spaces sizes for each translation context. However,
there are still some places in the code where the physical (resp.
virtual) address space size is assumed to be PLAT_PHY_ADDR_SPACE_SIZE
(resp. PLAT_VIRT_ADDR_SPACE_SIZE).

This patch removes them and reads the relevant address space size
from the translation context itself instead. This information is now
passed in argument to the enable_mmu_arch() function, which needs it
to configure the TCR_ELx.T0SZ field (in AArch64) or the TTBCR.T0SZ
field (in AArch32) appropriately.

Change-Id: I20b0e68b03a143e998695d42911d9954328a06aa
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>

xlat lib v2: Refactor the functions enabling the MMU ...

This patch refactors both the AArch32 and AArch64 versions of the
function enable_mmu_arch().

In both versions, the code now computes the VMSA-related system
registers upfront then program them in one go (rather than interleaving
the 2).

In the AArch64 version, this allows to reduce the amount of code
generated by the C preprocessor and limits it to the actual differences
between EL1 and EL3.

In the AArch32 version, this patch also removes the function
enable_mmu_internal_secure() and moves its code directly inside
enable_mmu_arch(), as it was its only caller.

Change-Id: I35c09b6db4404916cbb2e2fd3fda2ad59f935954
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>

xlat lib v2: Remove init_xlat_tables_arch() function ...

In both the AArch32 and AArch64 versions, this function used to check
the sanity of the PLAT_PHY_ADDR_SPACE_SIZE in regard to the
architectural maximum value. Instead, export the
xlat_arch_get_max_supported_pa() function and move the debug
assertion in AArch-agnostic code.

The AArch64 used to also precalculate the TCR.PS field value, based
on the size of the physical address space. This is now done directly
by enable_mmu_arch(), which now receives the physical address space size
in argument.

Change-Id: Ie77ea92eb06db586f28784fdb479c6e27dd1acc1
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>

Minor fixes to the xlat tables lib v2 ...

- Fix some comments.
- Remove duplicated definition.
- Make xlat_arch_get_max_supported_pa() private in aarch64.

Change-Id: I629237209cfb2ce7b0c4bd539d63dd81d45b2edd
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Merge pull request #924 from antonio-nino-diaz-arm/an/fix-xn-bit ...

Fix execute-never permissions in xlat tables libs

Use SPDX license identifiers ...

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>

Fix execute-never permissions in xlat tables libs ...

Translation regimes that only support one virtual address space (such as
the ones for EL2 and EL3) can flag memory regions as execute-never by
setting to 1 the XN bit in the Upper Attributes field in the translation
tables descriptors. Translation regimes that support two different
virtual address spaces (such as the one shared by EL1 and EL0) use bits
PXN and UXN instead.

The Trusted Firmware runs at EL3 and EL1, it has to handle translation
tables of both translation regimes, but the previous code handled both
regimes the same way, as if both had only 1 VA range.

When trying to set a descriptor as execute-never it would set the XN
bit correctly in EL3, but it would set the XN bit in EL1 as well. XN is
at the same bit position as UXN, which means that EL0 was being
prevented from executing code at this region, not EL1 as the code
intended. Therefore, the PXN bit was unset to 0 all the time. The result
is that, in AArch64 mode, read-only data sections of BL2 weren't
protected from being executed.

This patch adds support of translation regimes with two virtual address
spaces to both versions of the translation tables library, fixing the
execute-never permissions for translation tables in EL1.

The library currently does not support initializing translation tables
for EL0 software, therefore it does not set/unset the UXN bit. If EL1
software needs to initialize translation tables for EL0 software, it
should use a different library instead.

Change-Id: If27588f9820ff42988851d90dc92801c8ecbe0c9
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Control inclusion of helper code used for asserts ...

Many asserts depend on code that is conditionally compiled based on the
DEBUG define. This patch modifies the conditional inclusion of such code
so that it is based on the ENABLE_ASSERTIONS build option.

Change-Id: I6406674788aa7e1ad7c23d86ce94482ad3c382bd
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Add support to change xlat_tables to non-cacheable ...

This patch adds an additional flag `XLAT_TABLE_NC` which marks the
translation tables as Non-cacheable for MMU accesses.

Change-Id: I7c28ab87f0ce67da237fadc3627beb6792860fd4
Signed-off-by: Summer Qin <summer.qin@arm.com>

Apply workaround for errata 813419 of Cortex-A57 ...

TLBI instructions for EL3 won't have the desired effect under specific
circumstances in Cortex-A57 r0p0. The workaround is to execute DSB and
TLBI twice each time.

Even though this errata is only needed in r0p0, the current errata
framework is not prepared to apply run-time workarounds. The current one
is always applied if compiled in, regardless of the CPU or its revision.

This errata has been enabled for Juno.

The `DSB` instruction used when initializing the translation tables has
been changed to `DSB ISH` as an optimization and to be consistent with
the barriers used for the workaround.

Change-Id: Ifc1d70b79cb5e0d87e90d88d376a59385667d338
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Add dynamic region support to xlat tables lib v2 ...

Added APIs to add and remove regions to the translation tables
dynamically while the MMU is enabled. Only static regions are allowed
to overlap other static ones (for backwards compatibility).

A new private attribute (MT_DYNAMIC / MT_STATIC) has been added to
flag each region as such.

The dynamic mapping functionality can be enabled or disabled when
compiling by setting the build option PLAT_XLAT_TABLES_DYNAMIC to 1
or 0. This can be done per-image.

TLB maintenance code during dynamic table mapping and unmapping has
also been added.

Fixes ARM-software/tf-issues#310

Change-Id: I19e8992005c4292297a382824394490c5387aa3b
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Add version 2 of xlat tables library ...

The folder lib/xlat_tables_v2 has been created to store a new version
of the translation tables library for further modifications in patches
to follow. At the moment it only contains a basic implementation that
supports static regions.

This library allows different translation tables to be modified by
using different 'contexts'. For now, the implementation defaults to
the translation tables used by the current image, but it is possible
to modify other tables than the ones in use.

Added a new API to print debug information for the current state of
the translation tables, rather than printing the information while
the tables are being created. This allows subsequent debug printing
of the xlat tables after they have been changed, which will be useful
when dynamic regions are implemented in a patch to follow.

The common definitions stored in `xlat_tables.h` header have been moved
to a new file common to both versions, `xlat_tables_defs.h`.

All headers related to the translation tables library have been moved to
a the subfolder `xlat_tables`.

Change-Id: Ia55962c33e0b781831d43a548e505206dffc5ea9
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>