The self-relocating PrePi module that is used by the ArmVirtQemuKernel
and ArmVirtXen targets runs the linker in PIE mode so that it emits
dynamic relocations into the final image in a way that permits the
module to relocate itself into place before calling into the C code.
When building these targets using the CLANG38 toolchain, we switch
from the BFD to the GOLD linker, which behaves a bit differently when
building PIE executables, and insists on emitting GOT indirected symbol
references throughout, which means a) that we end up with absolute
addresses (which need to be fixed up at load time) for no good reason,
and b) we have to add support for handling GOT entries to GenFw if we
want to convert them into PE/COFF.
So instead, let's emit a shared library. Since the ELF image only serves
as the input to GenFw, this does not lead to any loss of functionality,
although it does require the -Bsymbolic linker option to be added to
ensure that no symbol based dynamic relocations are emitted (which
would, e.g., permit lazy binding for shared libraries). So for all
other toolchains, the linker option changes are a no-op.
Then, we have to convince CLANG38/GOLD that there is no need to refer
to symbols via a GOT entry. This is done by forcing hidden visibility
for all symbols in all components that make up the PrePi SEC module:
this informs the linker that a symbol is never exported or preempted,
making it safe to refer to it directly from anywhere in the code,
rather than indirectly via a GOT entry.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Laszlo Ersek <lersek@redhat.com>
As part of the effort to get rid of ArmPlatformLib (which incorporates
far too many duties in a single library), introduce ArmVirtMemInfoLib
which will be invoked by our ArmVirtMemoryInitPeiLib implementation to
get a description of the virtual address space. This will allow us to
remove this functionality from ArmPlatformLib later, or, in the case of
ArmVirtXen and ArmVirtQemuKernel, drop ArmPlatformLib altogether.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Now that the PL031 RTC driver library no longer depends on the ARM
platform specific ArmPlatformSysConfigLib, we no longer need to
implement ArmPlatform.h or have a resolution for that library.
This allows us to get rid of a rather dodgy practice of including
platform headers using compiler flags, which is a bad idea at various
levels.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Add high level methods to iterate over all 'reg' properties of all DT
nodes whose device_type properties have the value "memory". Since we are
modifying the FdtClient protocol, update the protocol and the only existing
implementation at the same time.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
The FDT client protocol methods dealing with "reg" properties return
the size of a "reg" element. Currently, we have hardcoded this as '8',
since #address-cells == #size-cells == 2 in most cases. However, for
different values, have a single 'reg' element size is not unambiguous,
since - however unlikely - if #address-cells != #size-cells, we do not
know which is which.
So before adding more methods to the protocol, fix up this oversight.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
This introduces the FdtClientProtocol, which will be used to expose the
device tree provided by the host to other DXE drivers.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Michael D Kinney
Ard Biesheuvel
Olivier Martin