"efi" global data structure contains "runtime_version" field which must
be assigned in order to use it later in Runtime Services virtual calls
(virt_efi_* functions).

Before this patch "runtime_version" was unassigned (0), so each
Runtime Service virtual call that checks revision would fail.
Signed-off-by: NSemen Protsenko <semen.protsenko@linaro.org>
Acked-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>

If we cannot resolve the virtual address of the UEFI System Table, its
physical offset must be missing from the virtual memory map, and there
is really no point in proceeding with installing the virtual memory map
and the runtime services dispatch table. So back out gracefully.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: NMark Salter <msalter@redhat.com>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>

According to the UEFI spec section 2.3.6.4, the use of FP/SIMD
instructions is allowed, and should adhere to the AAPCS64 calling
convention, which states that 'only the bottom 64 bits of each value
stored in registers v8-v15 need to be preserved' (section 5.1.2).

This applies equally to UEFI Runtime Services called by the kernel, so
make sure the FP/SIMD register file is preserved in this case. We do this
by enabling the wrappers for UEFI Runtime Services (CONFIG_EFI_RUNTIME_WRAPPERS)
and inserting calls to kernel_neon_begin()and kernel_neon_end() into
these wrappers.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>

Booting a kernel with CONFIG_EFI enabled on a non-EFI system caused
an oops with the current UEFI support code.
Add the required test to prevent this.
Signed-off-by: NLeif Lindholm <leif.lindholm@linaro.org>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>

This patch adds EFI runtime support for arm64. This runtime support allows
the kernel to access various EFI runtime services provided by EFI firmware.
Things like reboot, real time clock, EFI boot variables, and others.

This functionality is supported for little endian kernels only. The UEFI
firmware standard specifies that the firmware be little endian. A future
patch is expected to add support for big endian kernels running with
little endian firmware.
Signed-off-by: NMark Salter <msalter@redhat.com>
[ Remove unnecessary cache/tlb maintenance. ]
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Signed-off-by: NLeif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>