Enable v8.6 WFE trap delays ...

This patch enables the v8.6 extension to add a delay before WFE traps
are taken. A weak hook plat_arm_set_twedel_scr_el3 has been added in
plat/common/aarch64/plat_common.c that disables this feature by default
but platform-specific code can override it when needed.

The only hook provided sets the TWED fields in SCR_EL3, there are similar
fields in HCR_EL2, SCTLR_EL2, and SCTLR_EL1 to control WFE trap delays in
lower ELs but these should be configured by code running at EL2 and/or EL1
depending on the platform configuration and is outside the scope of TF-A.

Signed-off-by: John Powell <john.powell@arm.com>
Change-Id: I0a9bb814205efeab693a3d0a0623e62144abba2d

Fix exception in save/restore of EL2 registers. ...

Removing FPEXC32_EL2 from the register save/restore routine for EL2
registers since it is already a part of save/restore routine for
fpregs.

Signed-off-by: Max Shvetsov <maksims.svecovs@arm.com>
Change-Id: I5ed45fdbf7c8efa8dcfcd96586328d4f6b256bc4

Implement workaround for AT speculative behaviour ...

During context switching from higher EL (EL2 or higher)
to lower EL can cause incorrect translation in TLB due to
speculative execution of AT instruction using out-of-context
translation regime.

Workaround is implemented as below during EL's (EL1 or EL2)
"context_restore" operation:
1. Disable page table walk using SCTLR.M and TCR.EPD0 & EPD1
   bits for EL1 or EL2 (stage1 and stage2 disabled)
2. Save all system registers except TCR and SCTLR (for EL1 and EL2)
3. Do memory barrier operation (isb) to ensure all
   system register writes are done.
4. Restore TCR and SCTLR registers (for EL1 and EL2)

Errata details are available for various CPUs as below:
Cortex-A76: 1165522
Cortex-A72: 1319367
Cortex-A57: 1319537
Cortex-A55: 1530923
Cortex-A53: 1530924

More details can be found in mail-chain:
https://lists.trustedfirmware.org/pipermail/tf-a/2020-April/000445.html

Currently, Workaround is implemented as build option which is default
disabled.

Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
Change-Id: If8545e61f782cb0c2dda7ffbaf50681c825bd2f0

Merge changes I85eb75cf,Ic6d9f927 into integration ...

* changes:
  fconf: Update dyn_config compatible string
  doc: Add binding document for fconf.

fconf: Update dyn_config compatible string ...

Dynamic configuration properties are fconf properties. Modify the
compatible string from "arm,.." to "fconf,.." to reflect this.

Signed-off-by: Louis Mayencourt <louis.mayencourt@arm.com>
Change-Id: I85eb75cf877c5f4d3feea3936d4c348ca843bc6c

fdt/wrappers: Replace fdtw_read_cells() implementation ...

Our fdtw_read_cells() implementation goes to great lengths to
sanity-check every parameter and result, but leaves a big hole open:
The size of the storage the value pointer points at needs to match the
number of cells given. This can't be easily checked at compile time,
since we lose the size information by using a void pointer.
Regardless the current usage of this function is somewhat wrong anyways,
since we use it on single-element, fixed-length properties only, for
which the DT binding specifies the size.
Typically we use those functions dealing with a number of cells in DT
context to deal with *dynamically* sized properties, which depend on
other properties (#size-cells, #clock-cells, ...), to specify the number
of cells needed.

Another problem with the current implementation is the use of
ambiguously sized types (uintptr_t, size_t) together with a certain
expectation about their size. In general there is no relation between
the length of a DT property and the bitness of the code that parses the
DTB: AArch64 code could encounter 32-bit addresses (where the physical
address space is limited to 4GB [1]), while AArch32 code could read
64-bit sized properties (/memory nodes on LPAE systems, [2]).

To make this more clear, fix the potential issues and also align more
with other DT users (Linux and U-Boot), introduce functions to explicitly
read uint32 and uint64 properties. As the other DT consumers, we do this
based on the generic "read array" function.
Convert all users to use either of those two new functions, and make
sure we never use a pointer to anything other than uint32_t or uint64_t
variables directly.

This reveals (and fixes) a bug in plat_spmd_manifest.c, where we write
4 bytes into a uint16_t variable (passed via a void pointer).

Also we change the implementation of the function to better align with
other libfdt users, by using the right types (fdt32_t) and common
variable names (*prop, prop_names).

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi#n874
[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm/boot/dts/ecx-2000.dts

Change-Id: I718de960515117ac7a3331a1b177d2ec224a3890
Signed-off-by: Andre Przywara <andre.przywara@arm.com>

coreboot: Add memory range parsing ...

This patch adds code to parse memory range information passed by
coreboot, and a simple helper to test whether a specific address belongs
to a range. This may be useful for coreboot-using platforms that need to
know information about the system's memory layout (e.g. to check whether
an address passed in via SMC targets valid DRAM).

Signed-off-by: Julius Werner <jwerner@chromium.org>
Change-Id: I3bea326c426db27d1a8b7d6e17418e4850e884b4

locks: bakery: use is_dcache_enabled() helper ...

bakery_lock_normal.c uses the raw register accessor, read_sctlr(_el3)
to check whether the dcache is enabled.

Using is_dcache_enabled() is cleaner, and a good abstraction for
the library code like this.

A problem is is_dcache_enabled() is declared in the local header,
lib/xlat_tables_v2/xlat_tables_private.h

I searched for a good place to declare this helper. Moving it to
arch_helpers.h, closed to cache operation helpers, looks good enough
to me.

I also changed the type of 'is_cached' to bool for consistency,
and to avoid MISRA warnings.

Change-Id: I9b016f67bc8eade25c316aa9c0db0fa4cd375b79
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Merge "xlat_tables_v2: use get_current_el_maybe_constant() in is_dcache_enabled()" into integration

xlat lib v2: Add support to pass shareability attribute for normal memory region ...

Present framework restricts platform to pass desired shareability attribute
for normal memory region mapped in MMU. it defaults to inner shareability.

There are platforms where memories (like SRAM) are not placed at snoopable
region in advaned interconnect like CCN/CMN hence snoopable transaction is
not possible to these memory. Though These memories could be mapped in MMU
as MT_NON_CACHEABLE, data caches benefits won't be available.

If these memories are mapped as cacheable with non-shareable attribute,
when only one core is running like at boot time, MMU data cached could be
used for faster execution. Hence adding support to pass the shareability
attribute for memory regions.

Signed-off-by: Pramod Kumar <pramod.kumar@broadcom.com>
Change-Id: I678cb50120a28dae4aa9d1896e8faf1dd5cf1754

xlat_tables_v2: use get_current_el_maybe_constant() in is_dcache_enabled() ...

Using get_current_el_maybe_constant() produces more optimized code
because in most cases, we know the exception level at build-time.
For example, BL31 runs at EL3, so unneeded code will be trimmed.

[before]

0000000000000000 <is_dcache_enabled>:
   0:   d5384240        mrs     x0, currentel
   4:   53020c00        ubfx    w0, w0, #2, #2
   8:   7100041f        cmp     w0, #0x1
   c:   54000081        b.ne    1c <is_dcache_enabled+0x1c>  // b.any
  10:   d5381000        mrs     x0, sctlr_el1
  14:   53020800        ubfx    w0, w0, #2, #1
  18:   d65f03c0        ret
  1c:   7100081f        cmp     w0, #0x2
  20:   54000061        b.ne    2c <is_dcache_enabled+0x2c>  // b.any
  24:   d53c1000        mrs     x0, sctlr_el2
  28:   17fffffb        b       14 <is_dcache_enabled+0x14>
  2c:   d53e1000        mrs     x0, sctlr_el3
  30:   17fffff9        b       14 <is_dcache_enabled+0x14>

[after]

0000000000000000 <is_dcache_enabled>:
   0:   d53e1000        mrs     x0, sctlr_el3
   4:   53020800        ubfx    w0, w0, #2, #1
   8:   d65f03c0        ret

Change-Id: I3698fae9b517022ff9fbfd4cad3a320c6e137e10
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

xlat_tables_v2: fix assembler warning of PLAT_RO_XLAT_TABLES ...

If PLAT_RO_XLAT_TABLES is defined, the base xlat table goes to the
.rodata section instead of .bss section.

This causes a warning like:

/tmp/ccswitLr.s: Assembler messages:
/tmp/ccswitLr.s:297: Warning: setting incorrect section attributes for .rodata

It is practically no problem, but I want to keep the build log clean.

Put the base table into the "base_xlat_table" section to suppress the
assembler warnings.

The linker script determines its final destination; rodata section if
PLAT_RO_XLAT_TABLES=1, or bss section otherwise. So, the result is the
same.

Change-Id: Ic85d1d2dddd9b5339289fc2378cbcb21dd7db02e
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Merge "xlat_tables_v2: add enable_mmu()" into integration

fconf: exclude fconf_dyn_cfg_getter.c from BL1_SOURCES ...

fconf_dyn_cfg_getter.c calls FCONF_REGISTER_POPULATOR(), which populates
the fconf_populator structure.

However, bl1/bl1.ld.S does not have:

        __FCONF_POPULATOR_START__ = .;
        KEEP(*(.fconf_populator))
        __FCONF_POPULATOR_END__ = .;

So, this is not linked to bl1.elf

We could change either bl1/bl1.lds.S or lib/fconf/fconf.mk to make
them consistent.

I chose to fix up fconf.mk to keep the current behavior.

This is a groundwork to factor out the common code from linker scripts.

Change-Id: I07b7ad4db4ec77b57acf1588fffd0b06306d7293
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

xlat_tables_v2: add enable_mmu() ...

enable_mmu_* has a different function name, so it is not handy in the
shared code. enable_mmu() calls an appropriate one depending on the
exception level.

Change-Id: I0657968bfcb91c32733f75f9259f550a5c35b1c3
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

fconf: notify if fw_config dt is not used ...

Notify if fw_config dt is either not available or not loaded from fip.

Change-Id: I4dfcbe5032503d97f532a3287c5312c581578b68
Signed-off-by: Manish Pandey <manish.pandey2@arm.com>

Merge "fconf: Clean Arm IO" into integration

context: TPIDR_EL2 register not saved/restored ...

TPIDR_EL2 is missing from the EL2 state register save/restore
sequence. This patch adds it to the context save restore routines.

Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
Change-Id: I35fc5ee82f97b72bcedac57c791312e7b3a45251

fconf: Clean Arm IO ...

Merge the previously introduced arm_fconf_io_storage into arm_io_storage. This
removes the duplicate io_policies and functions definition.

This patch:
- replace arm_io_storage.c with the content of arm_fconf_io_storage.c
- rename the USE_FCONF_BASED_IO option into ARM_IO_IN_DTB.
- use the ARM_IO_IN_DTB option to compile out io_policies moved in dtb.
- propagate DEFINES when parsing dts.
- use ARM_IO_IN_DTB to include or not uuid nodes in fw_config dtb.
- set the ARM_IO_IN_DTB to 0 by default for fvp. This ensure that the behavior
  of fvp stays the same as it was before the introduction of fconf.

Change-Id: Ia774a96d1d3a2bccad29f7ce2e2b4c21b26c080e
Signed-off-by: Louis Mayencourt <louis.mayencourt@arm.com>

Merge changes from topic "mp/enhanced_pal_hw" into integration ...

* changes:
  plat/arm/fvp: populate pwr domain descriptor dynamically
  fconf: Extract topology node properties from HW_CONFIG dtb
  fconf: necessary modifications to support fconf in BL31 & SP_MIN
  fconf: enhancements to firmware configuration framework

Merge "locks: bakery: add a DMB to the 'read_cache_op' macro" into integration

fconf: enhancements to firmware configuration framework ...

A populate() function essentially captures the value of a property,
defined by a platform, into a fconf related c structure. Such a
callback is usually platform specific and is associated to a specific
configuration source.
For example, a populate() function which captures the hardware topology
of the platform can only parse HW_CONFIG DTB. Hence each populator
function must be registered with a specific 'config_type' identifier.
It broadly represents a logical grouping of configuration properties
which is usually a device tree source file.

Example:
> TB_FW: properties related to trusted firmware such as IO policies,
	 base address of other DTBs, mbedtls heap info etc.
> HW_CONFIG: properties related to hardware configuration of the SoC
	 such as topology, GIC controller, PSCI hooks, CPU ID etc.

This patch modifies FCONF_REGISTER_POPULATOR macro and fconf_populate()
to register and invoke the appropriate callbacks selectively based on
configuration type.

Change-Id: I6f63b1fd7a8729c6c9137d5b63270af1857bb44a
Signed-off-by: Madhukar Pappireddy <madhukar.pappireddy@arm.com>

xlat_tables_v2: merge REGISTER_XLAT_CONTEXT_{FULL_SPEC,RO_BASE_TABLE} ...

xlat_tables_v2_helpers.h defines two quite similar macros,
REGISTER_XLAT_CONTEXT_FULL_SPEC and REGISTER_XLAT_CONTEXT_RO_BASE_TABLE.

Only the difference is the section of _ctx_name##_base_xlat_table.

Parameterize it and unify these two macros.

The base xlat table goes into the .bss section by default.
If PLAT_RO_XLAT_TABLES is defined, it goes into the .rodata section.

Change-Id: I8b02f4da98f0c272e348a200cebd89f479099c55
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

cpus: denver: fixup register used to store return address ...

The denver_enable_dco and denver_disable_dco use register X3 to store
the return address. But X3 gets over-written by other functions,
downstream.

This patch stores the return address to X18 instead, to fix this
anomaly.

Change-Id: Ic40bfc1d9abaa7b90348843b9ecd09521bb4ee7b
Signed-off-by: Kalyani Chidambaram <kalyanic@nvidia.com>

locks: bakery: add a DMB to the 'read_cache_op' macro ...

ARM has a weak memory ordering model. This means that without
explicit barriers, memory accesses can be observed differently
than program order. In this case, the cache invalidate instruction
can be observed after the subsequent read to address.

To solve this, a DMB instruction is required between the cache
invalidate and the read. This ensures that the cache invalidate
completes before all memory accesses in program order after the DMB.

This patch updates the 'read_cache_op' macro to issue a DMB after
the cache invalidate instruction to fix this anomaly.

Change-Id: Iac9a90d228c57ba8bcdca7e409ea6719546ab441
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>

SPMD: Adds partially supported EL2 registers. ...

This patch adds EL2 registers that are supported up to ARMv8.6.
ARM_ARCH_MINOR has to specified to enable save/restore routine.

Note: Following registers are still not covered in save/restore.
 * AMEVCNTVOFF0<n>_EL2
 * AMEVCNTVOFF1<n>_EL2
 * ICH_AP0R<n>_EL2
 * ICH_AP1R<n>_EL2
 * ICH_LR<n>_EL2

Change-Id: I4813f3243e56e21cb297b31ef549a4b38d4876e1
Signed-off-by: Max Shvetsov <maksims.svecovs@arm.com>

SPMD: save/restore EL2 system registers. ...

NOTE: Not all EL-2 system registers are saved/restored.
This subset includes registers recognized by ARMv8.0

Change-Id: I9993c7d78d8f5f8e72d1c6c8d6fd871283aa3ce0
Signed-off-by: Jose Marinho <jose.marinho@arm.com>
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
Signed-off-by: Artsem Artsemenka <artsem.artsemenka@arm.com>
Signed-off-by: Max Shvetsov <maksims.svecovs@arm.com>

Merge changes from topic "console_t_cleanup" into integration ...

* changes:
  coreboot: Use generic base address
  skeletton: Use generic console_t data structure
  cdns: Use generic console_t data structure

coreboot: Use generic base address ...

Since now the generic console_t structure holds the UART base address as
well, let's use that generic location for the coreboot memory console.
This removes the base member from the coreboot specific data structure,
but keeps the struct console_cbmc_t and its size member.

Change-Id: I7f1dffd41392ba3fe5c07090aea761a42313fb5b
Signed-off-by: Andre Przywara <andre.przywara@arm.com>

Read-only xlat tables for BL31 memory ...

This patch introduces a build flag which allows the xlat tables
to be mapped in a read-only region within BL31 memory. It makes it
much harder for someone who has acquired the ability to write to
arbitrary secure memory addresses to gain control of the
translation tables.

The memory attributes of the descriptors describing the tables
themselves are changed to read-only secure data. This change
happens at the end of BL31 runtime setup. Until this point, the
tables have read-write permissions. This gives a window of
opportunity for changes to be made to the tables with the MMU on
(e.g. reclaiming init code). No changes can be made to the tables
with the MMU turned on from this point onwards. This change is also
enabled for sp_min and tspd.

To make all this possible, the base table was moved to .rodata. The
penalty we pay is that now .rodata must be aligned to the size of
the base table (512B alignment). Still, this is better than putting
the base table with the higher level tables in the xlat_table
section, as that would cost us a full 4KB page.

Changing the tables from read-write to read-only cannot be done with
the MMU on, as the break-before-make sequence would invalidate the
descriptor which resolves the level 3 page table where that very
descriptor is located. This would make the translation required for
writing the changes impossible, generating an MMU fault.

The caches are also flushed.

Signed-off-by: Petre-Ionut Tudor <petre-ionut.tudor@arm.com>
Change-Id: Ibe5de307e6dc94c67d6186139ac3973516430466