Commit Graph

6 Commits

Author SHA1 Message Date
Andre Przywara
15b6184971 armv8: Reduce exception handling code
The arm64 exception handling code is quite big, mostly due to
architectural alignment requirements. Each exception entry spans 32
instructions, which sounds generous, but is too small to fit all of the
save/branch/restore code in there. So at the moment we use only four
instructions, branching into shared save and restore routines.
To not leave the space for those remaining 28 instructions wasted, let's
split the save and restore routines and stuff them into the gaps.
This saves about 250 bytes of code, which is helpful for those tight
SPLs.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
2018-08-03 19:53:54 -04:00
Tom Rini
83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00
Andre Przywara
78ad457b2d armv8: shrink exception table code
In the moment our exception entry code needs 34 instructions, so we
can't use put it directly into the table entry, which offers "only"
32 instructions there. Right now we just put an unconditional branch
there, then use a macro to place the 34 instructions *per entry* after
that. That effectivly doubles the size of our exception table, which
is quite a waste, given that we use it mostly for debugging purposes.

Since the register saving part is actually identical, let's just convert
that macro into a function, and "bl" into it directly from the exception
slot, of course after having saved at least the original LR.
This saves us about 950 bytes of code, which is quite a relief for some
tight SPLs, in particular the 64-bit Allwinner ones.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
2017-12-04 09:59:02 -05:00
Alexander Graf
4c2cc7c4e9 arm64: Allow exceptions to return
Our current arm64 exception handlers all panic and never return to the
exception triggering code.

But if any handler wanted to continue execution after fixups, it would
need help from the exception handling code to restore all registers.

This patch implements that help. With this code, exception handlers on
aarch64 can successfully return to the place the exception happened (or
somewhere else if they modify elr).

Signed-off-by: Alexander Graf <agraf@suse.de>
2016-03-15 21:30:10 -04:00
Rob Herring
7682a99826 remove unnecessary version.h includes
Various files are needlessly rebuilt every time due to the version and
build time changing. As version.h is not actually needed, remove the
include.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Albert Aribaud <albert.u.boot@aribaud.net>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Minkyu Kang <mk7.kang@samsung.com>
Cc: Marek Vasut <marex@denx.de>
Cc: Tom Warren <twarren@nvidia.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Macpaul Lin <macpaul@andestech.com>
Cc: Wolfgang Denk <wd@denx.de>
Cc: York Sun <yorksun@freescale.com>
Cc: Stefan Roese <sr@denx.de>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Cc: Simon Glass <sjg@chromium.org>
Cc: Philippe Reynes <tremyfr@yahoo.fr>
Cc: Eric Jarrige <eric.jarrige@armadeus.org>
Cc: "David Müller" <d.mueller@elsoft.ch>
Cc: Phil Edworthy <phil.edworthy@renesas.com>
Cc: Robert Baldyga <r.baldyga@samsung.com>
Cc: Torsten Koschorrek <koschorrek@synertronixx.de>
Cc: Anatolij Gustschin <agust@denx.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Łukasz Majewski <l.majewski@samsung.com>
2015-03-24 10:50:50 -04:00
David Feng
0ae7653128 arm64: core support
Relocation code based on a patch by Scott Wood, which is:
Signed-off-by: Scott Wood <scottwood@freescale.com>

Signed-off-by: David Feng <fenghua@phytium.com.cn>
2014-01-09 16:08:44 +01:00