u-boot.git/arch/arc/lib/start.S, branch v2016.09

Fix board init code to respect the C runtime environment

2016-01-14T02:05:17+00:00

board_init_f_mem() alters the C runtime environment's
stack it is actually already using. This is not a valid
behaviour within a C runtime environment.

Split board_init_f_mem into C functions which do not alter
their own stack and always behave properly with respect to
their C runtime environment.

Signed-off-by: Albert ARIBAUD 
Acked-by: Thomas Chou

arc: significant cache rework

2015-07-01T14:17:27+00:00

[1] Align cache management functions to those in Linux kernel. I.e.:
    a) Use the same functions for all cache ops (D$ Inv/Flush)
    b) Split cache ops in 3 sub-functions: "before", "lineloop" and
"after". That way we may re-use "before" and "after" functions for
region and full cache ops.

 [2] Implement full-functional L2 (SLC) management. Before SLC was
simply disabled early on boot. It's also possible to enable or disable
L2 cache from config utility.

 [3] Disable/enable corresponding caches early on boot. So if U-Boot is
configured to use caches they will be used at all times (this is useful
in partucular for speed-up of relocation).

Signed-off-by: Alexey Brodkin

arc: add support for SLC (System Level Cache, AKA L2-cache)

2015-04-03T06:47:50+00:00

ARCv2 cores may have built-in SLC (System Level Cache, AKA L2-cache).
This change adds functions required for controlling SLC:
 * slc_enable/disable
 * slc_flush/invalidate

For now we just disable SLC to escape DMA coherency issues until either:
 * SLC flush/invalidate is supported in DMA APIin U-Boot
 * hardware DMA coherency is implemented (that might be board specific
   so probably we'll need to have a separate Kconfig option for
   controlling SLC explicitly)

Signed-off-by: Alexey Brodkin

arc: get rid of CONFIG_SYS_GENERIC_GLOBAL_DATA

2015-04-03T06:47:49+00:00

As discussed on mailing list we're drifting away from
CONFIG_SYS_GENERIC_GLOBAL_DATA in favour to use of board_init_f_mem()
for global data.

So do this for ARC architecture.

Signed-off-by: Alexey Brodkin

arc: clean-up init procedure

2015-04-03T06:47:49+00:00

Intention behind this work was elimination of as much assembly-written
code as it is possible.

In case of ARC we already have relocation fix-up implemented in C so why
don't we use C for U-Boot copying, .bss zeroing etc.

It turned out x86 uses pretty similar approach so we re-used parts of
code in "board_f.c" initially implemented for x86.

Now assembly usage during init is limited to stack- and frame-pointer
setup before and after relocation.

Signed-off-by: Alexey Brodkin 
Cc: Simon Glass

arc: move low-level interrupt and exception handlers in a separate file

2015-04-03T06:47:49+00:00

This separation makes maintenance of code easier because those low-level
interrupt- or exception handling routines are pretty static and usually
require not much care while start-up code is a subject of modifications
and enhancements.

Signed-off-by: Alexey Brodkin

arc: merge common start-up code between ARC and ARCv2

2015-04-03T06:47:49+00:00

Even though ARCompact and ARCv2 are not binary compatible most of
assembly instructions are used in both. With this change we'll get rid
of duplicate code.

Still IVTs are implemented differently so we're keeping them in separate
files.

Signed-off-by: Alexey Brodkin