GitLab

The functions represent ARM "thunk" code that can be invoked via
FEL to execute arbitrary memory copy operations on the target
device, i.e. they deal with overlap and unaligned access. Where
possible, the copy operation will use (32-bit) word transfers,
otherwise it falls back to bytewise copying.
Signed-off-by: Bernhard Nortmann <bernhard.nortmann@web.de>

The patch also introduces a "sid-register" command for diagnostic
purposes. It allows to use/enforce the workaround method for other
SoCs, to check if there are any inconsistencies with the values
read from memory.
Signed-off-by: Bernhard Nortmann <bernhard.nortmann@web.de>

The new function fel_get_sid_registers() uses ARM code for register
access to the SID root key. This is necessary to retrieve correct
values for certain SoCs, e.g. when not using this approach the H3
has been observed to return 'mangled' values (when reading SID from
memory).

See https://groups.google.com/forum/#!topic/linux-sunxi/ynyIP8c61Qs



The FEL library provides a uniform fel_get_sid_root_key() wrapper
that will automatically use the workaround method for SoCs that
are tagged accordingly - so the application program does not have
to bother with selecting memory vs. register-based access.
Signed-off-by: Bernhard Nortmann <bernhard.nortmann@web.de>

This is a preparatory step. Instead of using memory-based access,
we might want to retrieve SID keys (e-fuses) via SID registers.
For this, it's convenient if the plain base address is available.
Signed-off-by: Bernhard Nortmann <bernhard.nortmann@web.de>

Signed-off-by: Bernhard Nortmann <bernhard.nortmann@web.de>

open_fel_device() will automatically provide this member field,
based on the SoC ID from FEL/BROM version data. The field will
either receive a human-readable identifier, or the ID in 4-digit
hexadecimal representation (for unknown SoCs).
Signed-off-by: Bernhard Nortmann <bernhard.nortmann@web.de>

Signed-off-by: Bernhard Nortmann <bernhard.nortmann@web.de>

The feldev_handle struct returned by feldev_open() will now contain
this additional data, so the main application no longer needs to care
about retrieving that.

aw_fel_get_version() has thus become a static (= 'private') function.
Signed-off-by: Bernhard Nortmann <bernhard.nortmann@web.de>

Signed-off-by: Bernhard Nortmann <bernhard.nortmann@web.de>

The FEL utility had accumulated enough (mostly USB-related)
"low-level" code to justify moving that to a separate code unit.
This will allow us to keep better focus on the higher level
functionality in fel.c.
Signed-off-by: Bernhard Nortmann <bernhard.nortmann@web.de>