Commit graph

80 commits

Author SHA1 Message Date
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
Daniel Schwierzeck
eef88dfb3e MIPS: unify CPU code in arch/mips/cpu/
Unify and move code in arch/mips/cpu/mips[32|64]/ to arch/mips/cpu/.
The CPU specific config.mk files need to remain until
CONFIG_STANDALONE_LOAD_ADDR is converted to a global Kconfig symbol.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2015-01-30 14:19:58 +01:00
Daniel Schwierzeck
d9a4a6223c MIPS: move au1x00 SoC code to arch/mips/mach-au1x00
Move all au1x00 code out of arch/mips/cpu/mips32 to allow
unification of CPU code in a later patch. The reorganization
of the SoC specific header files will be done in a later patch
series.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: Paul Burton <paul.burton@imgtec.com>
2015-01-30 14:19:58 +01:00
Paul Burton
f1c64a0810 MIPS: handle mips64 ST0_KX bit in mips32 start.S
In preparation for sharing a single copy of start.S between mips32 &
mips64, handle setting the KX bit of the cop0 Status register when the
mips32 start.S is built for mips64.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2015-01-30 14:19:58 +01:00
Paul Burton
ab0d002677 MIPS: handle mips64 relocs in mips32 start.S
In preparation for sharing a single copy of start.S between mips32 &
mips64, handle mips64 relocations in the mips32 start.S when built for
mips64.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2015-01-30 14:19:58 +01:00
Paul Burton
a39b1cb7f0 MIPS: use asm.h macros in mips32 start.S
Where the mips32 & mips64 implementations of start.S differ in terms of
access sizes & offsets, use the appropriate macros from asm.h to
abstract those differences away. This is in preparation for sharing a
single copy of start.S between mips32 & mips64.

The exception to this is loads of immediates to be written to the cop0
Config register, which is a 32bit register on mips64 and therefore
constants written to it can be loaded as such.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2015-01-30 14:19:57 +01:00
Paul Burton
4a5d8898bc MIPS: unify cache initialization code
The mips32 & mips64 cache initialization code differs only in that the
mips32 code supports reading the cache size from coprocessor 0 registers
at runtime. Move the more developed mips32 version to a common
arch/mips/lib/cache_init.S & remove the now-redundant mips64 version in
order to reduce duplication. The temporary registers used are shuffled
slightly in order to work for both mips32 & mips64 builds. The RA
register is defined differently to suit mips32 & mips64, but will be
removed by a later commit in the series after further cleanup.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2015-01-29 12:55:01 +01:00
Paul Burton
30374f98d1 MIPS: unify cache maintenance functions
Move the more developed mips32 version of the cache maintenance
functions to a common arch/mips/lib/cache.c, in order to reduce
duplication between mips32 & mips64.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2015-01-29 12:55:00 +01:00
Paul Burton
2b8bcc5a2f MIPS: avoid .set ISA for cache operations
As a step towards unifying the cache maintenance code for mips32 &
mips64 CPUs, stop using ".set <ISA>" directives in the more developed
mips32 version of the code. Instead, when present make use of the GCC
builtin for emitting a cache instruction. When not present, simply don't
bother with the .set directives since U-boot always builds with
-march=mips32 or higher anyway.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2015-01-29 12:55:00 +01:00
Daniel Schwierzeck
e520023882 MIPS: add support for pre-relocation malloc
Implement MIPS specific setup of the gd_t structure to support
pre-relocation malloc. If CONFIG_SYS_MALLOC_F_LEN is specified,
a memory area will be reserved after the initial stack area and
the gd->malloc_base pointer will be initialized.

After this patch the new driver model can be used on MIPS.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2015-01-21 14:07:23 +01:00
Daniel Schwierzeck
dd82128ef5 MIPS: add support for CONFIG_SYS_INIT_SP_ADDR
Support the existing config option CONFIG_SYS_INIT_SP_ADDR on
MIPS. This allows to move the initial stack to other places
than the beginning of RAM.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2015-01-21 14:07:16 +01:00
Thomas Langer
a18a477147 MIPS: use common code from lib/time.c
The common code just needs the C0_COUNT as free running counter,
without the need of writing and checking C0_COMPARE.

The function get_tbclk() is still implemented here instead of changing
all places of CONFIG_SYS_MIPS_TIMER_FREQ to CONFIG_SYS_TIMER_RATE.

The change was tested on a MIPS32 system, but as the MIPS64 code
was/is the same, this should be no problem.

Signed-off-by: Thomas Langer <thomas.langer@lantiq.com>
2015-01-21 14:02:49 +01:00
Daniel Schwierzeck
6d08e22aca MIPS: fix setup of initial stack frame
To get correct stack walking and backtrace functionality in gdb,
registers fp and ra should be initialized before calling board_init_f
or board_init_r. Thus allocating stack space and zeroing it as it is
currently done in board.c becomes obsolete.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2014-11-27 16:20:37 +01:00
Masahiro Yamada
56f31e872e kbuild: use SoC-specific CONFIG to descend into SoC directory
Use "obj-$(CONFIG_FOO) += foo/" where it is possible.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
2014-11-23 06:49:02 -05:00
Masahiro Yamada
165ecd26f0 kbuild: Descend into SOC directory from CPU directory
Some CPUs of some architectures have SOC directories.
At present, the build system directly descends into SOC directories
from the top Makefile, but it should generally descend into each
directory from its parent directory.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
2014-11-23 06:49:02 -05:00
Masahiro Yamada
cba1da495d include: move various macros to include/linux/kernel.h
U-Boot has imported various utility macros from Linux
scattering them to various places without consistency.

In include/common.h are min, max, min3, max3, ARRAY_SIZE, ALIGN,
container_of, DIV_ROUND_UP, etc.
In include/linux/compat.h are min_t, max_t, round_up, round_down,
etc.
We also have duplicated defines of min_t in some *.c files.

Moreover, we are suffering from too cluttered include/common.h.

This commit moves various macros that originate in
include/linux/kernel.h of Linux to their original position.

Note:
This commit simply moves the macros; the macros roundup,
min, max, min2, max3, ARRAY_SIZE are different
from those of Linux at this point.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
2014-11-20 11:28:25 -05:00
Daniel Schwierzeck
837cad1e47 MIPS: refactor setting of compiler options
Refactor and unify all compiler settings in arch/mips/config.mk.
Also add tune flags for each supported CPU type.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2014-11-01 18:18:05 +01:00
Daniel Schwierzeck
538cf92c8c MIPS: drop incaip board
This is dead hardware and no one is interested in making the
necessary changes for upcoming features like generic board or
driver model.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: Wolfgang Denk <wd@denx.de>
2014-04-20 13:16:43 +02:00
Paul Burton
186d8159f6 MIPS: stub interrupt_init function
interrupt_init is called unconditionally by the generic board code.
Define a stub for it on MIPS like the enable & disable functions.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
2014-04-20 13:16:42 +02:00
Stephen Warren
eb838e7d84 usb: create common header virtual root hub descriptors
Many USB host controller drivers contain almost identical copies of the
same virtual root hub descriptors. Put these into a common file to avoid
duplication.

Note that there were some very minor differences between the descriptors
in the various files, such as:

- USB 1.0 vs. USB 1.1
- Manufacturer/Device ID
- Max packet size
- String content

I assume these aren't relevant.

Cc: Thomas Lange <thomas@corelatus.se>
Cc: Shinya Kuribayashi <skuribay@pobox.com>
Cc: Gary Jennejohn <garyj@denx.de>
Cc: Wolfgang Denk <wd@denx.de>
Cc: Eric Millbrandt <emillbrandt@coldhaus.com>
Cc: Pierre Aubert <p.aubert@staubli.com>
Cc: Stefan Roese <sr@denx.de>
Cc: Daniel Hellstrom <daniel@gaisler.com>
Cc: Denis Peter <d.peter@mpl.ch>
Cc: Rodolfo Giometti <giometti@linux.it>
Cc: Zhang Wei <wei.zhang@freescale.com>
Cc: Mateusz Zalega <m.zalega@samsung.com>
Cc: Remy Bohmer <linux@bohmer.net>
Cc: Markus Klotzbuecher <mk@denx.de>
Cc: Minkyu Kang <mk7.kang@samsung.com>
Cc: Gary Jennejohn <garyj@denx.de>
Cc: C Nauman <cnauman@diagraph.com>
Cc: David Müller <d.mueller@elsoft.ch>
Cc: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Cc: Thomas Abraham <t-abraham@ti.com>
Cc: Tom Rini <trini@ti.com>
Cc: Andrew Murray <amurray@embedded-bits.co.uk>
Cc: Matej Frančeškin <matej.franceskin@comtrade.com>
Cc: Cliff Cai <cliff.cai@analog.com>
Cc: Bryan Wu <cooloney@gmail.com>
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
2014-03-10 18:53:36 +01:00
Masahiro Yamada
cfda6bd2d8 mips: move CONFIG_MIPS{32, 64} definition to config.mk
All mips32 boards define CONFIG_MIPS32 in config headers
except malta boards which define it in boards.cfg.
We can consolidate them by defining it in
arch/mips/cpu/mips32/config.mk.

CONFIG_MIPS64 definition can be moved to
arch/mips/cpu/mips64/config.mk as well.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Acked-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2014-03-07 10:59:06 -05:00
Masahiro Yamada
a0a15b441c config.mk: specify the exact path to standalone linker script
We want to change the build system to include config.mk
only from ./Makefile and spl/Makefile.
We must prepare for that in this commit.

$(src) is a moving target and not handy for our purpose.
We must replace it with a fixed path.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
2014-03-07 10:59:06 -05:00
Masahiro Yamada
9e4140329e kbuild: change out-of-tree build
This commit changes the working directory
where the build process occurs.

Before this commit, build process occurred under the source
tree for both in-tree and out-of-tree build.

That's why we needed to add $(obj) prefix to all generated
files in makefiles like follows:
  $(obj)u-boot.bin:  $(obj)u-boot

Here, $(obj) is empty for in-tree build, whereas it points
to the output directory for out-of-tree build.

And our old build system changes the current working directory
with "make -C <sub-dir>" syntax when descending into the
sub-directories.

On the other hand, Kbuild uses a different idea
to handle out-of-tree build and directory descending.

The build process of Kbuild always occurs under the output tree.
When "O=dir/to/store/output/files" is given, the build system
changes the current working directory to that directory and
restarts the make.

Kbuild uses "make -f $(srctree)/scripts/Makefile.build obj=<sub-dir>"
syntax for descending into sub-directories.
(We can write it like "make $(obj)=<sub-dir>" with a shorthand.)
This means the current working directory is always the top
of the output directory.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Tested-by: Gerhard Sittig <gsi@denx.de>
2014-02-19 11:07:50 -05:00
Paul Burton
7a9d109b00 qemu-malta: rename to just "malta"
This is in preparation for adapting this board to function correctly on
a physical MIPS Malta board. The board is moved into an "imgtec" vendor
directory at the same time in order to ready us for any other boards
supported by Imagination in the future.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
2013-11-09 17:21:01 +01:00
Paul Burton
fa476f75bf mips32: detect L1 cache sizes if they're not defined
For boards such as the MIPS Malta with an FPGA core card it is desirable
to be able to detect the L1 cache sizes at runtime, since they are not
dependant upon the board but on the FPGA bitstream in use. This patch
performs that detection when the CONFIG_SYS_[DI]CACHE_SIZE macros are
not defined by the board configuration. In cases where the sizes are
detected this patch also removes the restriction that the I-cache &
D-cache line sizes must be the same, as this is not necessarily true.

If the cache sizes are defined by a configuration then they will be
hardcoded as before, so this patch will not add overhead to such
boards.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
2013-11-09 17:21:01 +01:00
Masahiro Yamada
f6e2c0f3e3 mips: convert makefiles to Kbuild style
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
2013-10-31 13:26:45 -04:00
Troy Kisky
06d513ecb6 usb: add enum usb_init_type parameter to usb_lowlevel_init
This parameter will later be used to verify OTG ports.

Signed-off-by: Troy Kisky <troy.kisky@boundarydevices.com>
2013-10-20 23:45:26 +02:00
Wolfgang Denk
3765b3e7bd Coding Style cleanup: remove trailing white space
Signed-off-by: Wolfgang Denk <wd@denx.de>
2013-10-14 16:06:53 -04:00
Gabor Juhos
db2c86d7d7 MIPS: mips32/cache.S: use v1 register for indirect function calls
Synchronize the code with mips64/cache.S, in order to
allow further unifications.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
2013-07-24 09:51:07 -04:00
Gabor Juhos
ee8b1e2959 MIPS: mips32/cache.S: store cache line size in t8 register
Synchronize the code with mips64/cache.S, in order to
allow further unifications.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
2013-07-24 09:51:07 -04:00
Gabor Juhos
c325916563 MIPS: mips32/cache.S: save return address in t9 register
Synchronize the code with mips64/cache.S, in order to
allow further unifications.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
2013-07-24 09:51:06 -04:00
Gabor Juhos
691995f9ab MIPS: mips32/start.S: rework relocation info check
Make it similar to the code in mips64/start.S, in order to
allow further unifications.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
2013-07-24 09:51:05 -04:00
Gabor Juhos
680cb2dc3a MIPS: mips32/start.S: use t8 register for dynamic relocation
Synchronize the code with mips64/start.S, in order to
allow further unifications.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
2013-07-24 09:51:05 -04:00
Gabor Juhos
da84f33b04 MIPS: mips32/cache.S: remove superfluous register assignment
The t4 register already holds the cache
line size, and the value of the register
is not changed in mips_init_icache.

Get the cache line size value from t4 for
mips_init_dcache as well and remove the
superfluous assignment of t5 register.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
2013-07-24 09:51:05 -04:00
Gabor Juhos
c3e4901fc6 MIPS: mips32/time.c: fix checkpatch errors/warnings
Checking mips32/time.c with checkpatch.pl shows this:

  arch/mips/cpu/mips32/time.c:30: WARNING: line over 80 characters
  arch/mips/cpu/mips32/time.c:57: ERROR: return is not a function, parentheses are not required
  total: 1 errors, 1 warnings, 0 checks, 85 lines checked

Fix the code to make checkpatch.pl happy.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
2013-07-24 09:51:04 -04:00
Gabor Juhos
843a76b66b MIPS: start.S: emulate REVISION register for qemu-malta
On the origial Malta boards the REVISION register is
accessible at the 0x1fc00010 address. The contents of
this register gives information about the revision
of the Malta and Core Boards.

This register is used by the Linux kernel to identify
the actual board it is running on. However the register
is not emulated properly by Qemu, so put a hardcoded
value into the flash to make Linux work.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
2013-07-24 09:51:03 -04:00
Wolfgang Denk
1a4596601f Add GPL-2.0+ SPDX-License-Identifier to source files
Signed-off-by: Wolfgang Denk <wd@denx.de>
[trini: Fixup common/cmd_io.c]
Signed-off-by: Tom Rini <trini@ti.com>
2013-07-24 09:44:38 -04:00
Gabor Juhos
04380c651a MIPS: add dynamic relocation support
The code handles relocation entries with the
following relocation types only:
  mips32: R_MIPS_REL32
  mips64: R_MIPS_REL+R_MIPS_64
  xburst: R_MIPS_REL32

Other relocation entries are skipped without
processing. The code must be extended if other
relocation types must be supported.

Add -pie to LDFLAGS_FINAL to generate the .rel.dyn
fixup table, which will be applied to the relocated
image before transferring control to it.

The CONFIG_NEEDS_MANUAL_RELOC is not needed
after the patch, so remove that as well.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2013-02-12 22:22:13 +01:00
Daniel Schwierzeck
28875e2c47 MIPS: start.S: use symbol __image_copy_end for U-Boot image relocation
Use the newly introduced symbol __image_copy_end as end address for
relocation of U-Boot image. This is needed for dynamic relocation added
in later patches. This patch obsoletes the symbols uboot_end and
uboot_end_data which are removed.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2013-02-12 22:22:13 +01:00
Daniel Schwierzeck
696a3b2a53 MIPS: start.S: optimize BSS initialization
Get the start and end address for clearing BSS from the newly
introduced symbols __bss_start and __bss_end. After GOT is
relocated, those symbols are already pointing to the correct
addresses.

Also optimize the loop by moving the address incrementation
to the delay slot to avoid the initial sub instruction.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2013-02-12 22:22:13 +01:00
Daniel Schwierzeck
8b1c7345c6 MIPS: start.S: unify and simplify reset vector handling
Adopt reset vector handling from Yamon.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2013-02-12 22:22:12 +01:00
Daniel Schwierzeck
4dc7412afa MIPS: start.S: remove obsolete 64 bit handling in setup_c0_status
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2013-02-12 22:22:12 +01:00
Gabor Juhos
9950b90d38 MIPS: remove OUTPUT_FORMAT from linker scripts
The OUTPUT_FORMAT command in linker scripts
was always misused due to some endianess and
toolchain problems.

Use GCC flags to ensure proper output format,
and get rid of the OUTPUT_FORMAT commands in
the board specific u-boot.lds files.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
Cc: Stefan Roese <sr@denx.de>
Cc: Wolfgang Denk <wd@denx.de>
Cc: Xiangfu Liu <xiangfu@openmobilefree.net>
2013-01-30 23:34:10 +01:00
Gabor Juhos
025f2b3380 MIPS: simplify relocated _G_O_T_ address calculation
The difference between the address of the original
and the relocated _GLOBAL_OFFSET_TABLE_ is always
the same as the relocation offset.

The relocation offset is already computed and it is
available in the 's1/t6' register. Use that to adjust
the relocated _G_O_T_ address, instead of calculating
the offset again from the _gp value.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
Cc: Xiangfu Liu <xiangfu@openmobilefree.net>
2013-01-30 23:32:52 +01:00
Gabor Juhos
67d80c9f97 MIPS: start.S: don't save flush_cache parameters in advance
Saving the parameters in advance unnecessarily complicates
the code. The destination address is already saved in the
's2' register, and that register is not clobbered by the
copy loop. The size of the copied data can be computed
after the copy loop is done.

Change the code to compute the size parameter right
before calling flush_cache, and set the destination
address parameter in the delay slot of the actuall
call.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
2013-01-27 16:40:15 +01:00
Gabor Juhos
248fe03f53 MIPS: start.S: simplify relocation offset calculation
The current code uses four instructions and a
temporary register to calculate the relocation
offset and to adjust the gp register.

The relocation offset can be calculated directly
from the CONFIG_SYS_MONITOR_BASE constant and from
the destination address. The resulting offset can
be used to adjust the gp pointer.

This approach makes the code a bit simpler because
it needs two instructions only.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
2013-01-27 16:40:07 +01:00
Gabor Juhos
b2fe86f887 MIPS: start.S: save reused arguments earlier in relocate_code
Save the reused parameters at the beginning
of the 'relocate_code' function. This makes
the function a bit more readable.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
2013-01-27 16:39:59 +01:00
Gabor Juhos
f321b0f99f MIPS: start.S: set sp register directly
The current code uses two instructions to load
the stack pointer into the 'sp' register.

This results in the following assembly code:

    468:   3c088040        lui     t0,0x8040
    46c:   251d0000        addiu   sp,t0,0

The first instuction loads the stack pointer into
the 't0' register then the value of the 'sp' register
is computed by adding zero to the value of the 't0'
register. The same issue present on the 64-bit version
as well:

    56c:   3c0c8040        lui     t0,0x8040
    570:   659d0000        daddiu  sp,t0,0

Change the code to load the stack pointer directly
into the 'sp' register. The generated code is functionally
equivalent to the previous version but it is simpler.

  32-bit:
    468:   3c1d8040        lui     sp,0x8040

  64-bit:
    56c:   3c1d8040        lui     sp,0x8040

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
2013-01-27 16:39:51 +01:00
Gabor Juhos
5b7dd8163d MIPS: start.S: fix boundary check in relocate_code
The loop code copies more data with one than
necessary due to the 'ble' instuction. Use the
'blt' instruction instead to fix that.

Due to the lack of suitable hardware the Xburst
specific code is compile tested only. However the
change is quite obvious.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
2013-01-27 16:39:43 +01:00
Gabor Juhos
14fdd1a8bf MIPS: start{, 64}.S: fill branch delay slots with NOP instructions
The romReserved and romExcHandle handlers are
accessed by a branch instruction however the
delay slots of those instructions are not filled.

Because the start.S uses the 'noreorder' directive,
the assembler will not fill the delay slots either,
and leads to the following assembly code:

  0000056c <romReserved>:
   56c:   1000ffff        b       56c <romReserved>

  00000570 <romExcHandle>:
   570:   1000ffff        b       570 <romExcHandle>

In the resulting code, the second branch instruction
is placed into the delay slot of the first branch
instruction, which is not allowed on the MIPS
architecture.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
2013-01-22 21:09:34 +01:00