Commit Graph

7 Commits

Author SHA1 Message Date
Andy Ross
55a85771b0 arch/x86: Make EFI copies bytewise
Originally the EFI boot code was written to assume that all sections
in the ELF file were 8-byte aligned and sized (because I thought this
was part of some platform spec somewhere).  This turned out to be
wrong in practice (at least for section sizes), so the requirement was
reduced to 4 bytes.  But now we have a section being generated
somewhere that turns out to violate even that.

There's no particular value in doing those copies in big chunks.
There's at best a mild performance benefit, but if we really cared
we'd be using a more complicated memcpy() implementation anyway.
Replace the loop in the C code with a bytewise copy, change the size
field in the generated header to store bytes, and remove the
assertions (which were the failuers actually being seen in practice)
in the script that were there to detect this misalignment.

Fixes #29095

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2020-10-13 14:07:24 -07:00
David Leach
565a61dd79 arch/x86: zefi: Fix mismatch in printf with args
printf function didn't have enough specifiers for the
number of arguments in the command line (Coverity warning).

Fixes #26985
Fixes #26986

Signed-off-by: David Leach <david.leach@nxp.com>
2020-07-24 21:51:14 -04:00
Johan Hedberg
38333afe0e arch: x86: zefi: Reduce data section alignment requirement from 8 to 4
It's not safe to assume that the data section is 8-byte aligned.
Assuming 4-byte alignment seems to work however, and results in
simpler code than arbitrary alignment support.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2020-07-18 08:44:31 -04:00
Anas Nashif
4382532fd3 x86: zefi: support arguments and make compatible with windows
Add argument parsing and use os.path.join where possible to support
building on windows.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2020-07-18 08:44:31 -04:00
Johan Hedberg
0329027bd8 arch: x86: zefi: Fix assuming segment size being a multiple of 8
The p_memsz field which indicates the size of a segment in memory
isn't always a multiple of 8. Remove the assert and add padding if
necessary. Without this change it's not possible to generate EFI
binaries out of all samples & tests in the tree.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2020-07-14 18:21:38 -04:00
Andy Ross
2626d702c6 arch/x86: zefi must disable HPET before OS handoff
The firmware on existing devices uses HPET timer zero for its own
purposes, and leaves it alive with interrupts enabled.  The Zephyr
driver now knows how to recover from this state with fuller
initialization, but that's not enough to fix the inherent race:

The timer can fire BEFORE the driver initialization happens (and does,
with certain versions of the EFI shell), thus flagging an interrupt to
what Zephyr sees as a garbage vector.  The OS can't fix this on its
own, the EFI bootloader (which is running with interrupts enabled as
part of the EFI environment) has to do it.  Here we can know that our
setting got there in time and didn't result in a stale interrupt flag
in the APIC waiting to blow up when interrupts get enabled.

Note: this is really just a workaround.  It assumes the hardware has
an HPET with a standard address.  Ideally we'd be able to build zefi
using Zephyr kconfig and devicetree values and predicate the HPET
reset on the correct configuraiton.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2020-07-08 12:34:09 +02:00
Andy Ross
928d31125f arch/x86: Add zefi, an EFI stub/packer/wrappper/loader
This is a first cut on a tool that will convert a built Zephyr ELF
file into an EFI applciation suitable for launching directly from the
firmware of a UEFI-capable device, without the need for an external
bootloader.

It works by including the Zephyr sections into the EFI binary as
blobs, then copying them into place on startup.

Currently, it is not integrated in the build.  Right now you have to
build an image for your target (up_squared has been tested) and then
pass the resulting zephyr.elf file as an argument to the
arch/x86/zefi/zefi.py script.  It will produce a "zephyr.efi" file in
the current directory.

This involved a little surgery in x86_64 to copy over some setup that
was previously being done in 32 bit mode to a new EFI entry point.
There is no support for 32 bit UEFI targets for toolchain reasons.

See the README for more details.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2020-07-02 09:10:01 -04:00