u-boot.git/arch/sh/cpu, branch v2017.01

sh: generate position independent code for all platforms

2016-12-03T02:32:54+00:00

Finally add fpic compilation option to produce relocatable code.
Note that this requires to define CONFIG_NEEDS_MANUAL_RELOC for all
board files, also relocation support still has some limitations
(e.g. a developer should care not to overwrite the executing code or
memset() with zeroes not yet relocated data on malloc init etc.),
which may be fixed while switching to PIE.

Due to short investigation the architecture code is not ready for PIE
linking, this will require some manipulations with .dyn* sections.

Signed-off-by: Vladimir Zapolskiy

sh: share the correct version of start.S among all cpus

2016-12-03T02:32:53+00:00

It is easy to note that SH2/SH3/SH4 start.S code is practically
the same with a minor difference for SH2 where a short data header is
present. To avoid unwanted code duplication and to automatically
convert SH2 and SH3 platforms to generic board support move fixed SH4
start.S into arch/sh/lib/start.S and share it among all platforms.

Signed-off-by: Vladimir Zapolskiy 
Reviewed-by: Simon Glass

sh4: fix start.S by calling board_init_f() after first code relocation

2016-12-03T02:32:53+00:00

Like on ARM platform keep the first code relocation from a U-boot
image storage to RAM at CONFIG_SYS_TEXT_BASE, then pass execution to a
generic board_init_f() with empty GD flags. If CONFIG_SYS_TEXT_BASE is
equal to a calculated by board_init_f() relocation address there will
be no more code and data copy, however it's worth to mention that the
first copy happens even if $pc on _start is the same as
CONFIG_SYS_TEXT_BASE, on practice this works without a problem.

Also note that _sh_start is renamed back to _start to correct
gd->mon_len calculation by setup_mon_len(), the opposite rename was
done in pre-generic board commit 2024b968ee9 ("sh: Fix build in start.S").

Signed-off-by: Vladimir Zapolskiy 
Reviewed-by: Simon Glass

sh: add shared relocate_code() function and call board_init_r()

2016-12-03T02:32:52+00:00

Commits b61e90e6fd83 ("sh: Drop the arch-specific board init") and
f41e6088eb1a ("sh: Fix build errors for generic board") left code and
data relocation done in start.S, however further actual U-boot
configuration is not started anymore. Practically SH boards with the
code relocated into the expected position by start.S still can be
booted, so the change adds this option and provides an option how to
relocate code for board_init_r() execution.

Signed-off-by: Vladimir Zapolskiy 
Reviewed-by: Simon Glass

sh: add MEMORY command to a shared linker script

2016-12-03T02:32:48+00:00

At the moment in runtime all defined sections are copied into or
created in RAM, specify this explicitly to assert potential out of RAM
placements of the sections.

Signed-off-by: Vladimir Zapolskiy 
Reviewed-by: Simon Glass

sh: define entry point and reloc_dst inside a linker script

2016-12-03T02:32:48+00:00

No functional change, concentrate linker script commands in one
place for convenience. Entry point is set to CONFIG_SYS_TEXT_BASE by
default on build, so this option can be omitted from being added to
the linker script.

Signed-off-by: Vladimir Zapolskiy 
Reviewed-by: Simon Glass

sh: place board lowlevel_init code in the beginning of .text

2016-12-03T02:32:47+00:00

Reference lowlevel_init of all supported SH2A/SH3/SH4/SH4A boards
from a shared linker script, the lowlevel_init function will be called
by a relative address.

Signed-off-by: Vladimir Zapolskiy 
Reviewed-by: Simon Glass

sh4: use single u-boot linker script for all boards

2016-12-03T02:32:46+00:00

Three supported SH4/SH4A boards with the bootloader image stored on
SPI flash have own flavour of a linker script, in turn they are equal
among each other. The only difference is that the text from
lowlevel_init.o is placed right after start.o, which makes sense.

Note that .bss section is not marked as NOLOAD, because for about
10 years this is a default option of a GNU linker, either the
attribute is found or not the resulting image file is the same.

Signed-off-by: Vladimir Zapolskiy 
Reviewed-by: Simon Glass

sh4: cache: move exported cache manipulation functions into cache.c

2016-12-03T02:32:42+00:00

No functional change, moving cache manipulation functions into cache.c
allows to collect all of them in a single location and as a pleasant
side effect cache_control() function can be unexported now.

Signed-off-by: Vladimir Zapolskiy 
Reviewed-by: Simon Glass

sh: cache: don't modify CCR from P1 area

2016-12-03T02:32:41+00:00

cache_wback_all() is a local function and it is called from
cache_control() only, which is in turn jumps to P2 area.

The change fixes an issue when cache_wback_all() returns from P2 to
P1, however cache_control() continues to manipulate with CCR
register, according to the User's Manual this is restricted.

Signed-off-by: Vladimir Zapolskiy