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>
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>
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>
Currently the cache operation mode is hard-coded to
CONF_CM_CACHABLE_NONCOHERENT. This is not appropiate for CPUs or SOCs
which operate at a different mode.
This patch makes the cache operation mode configurable via board config.
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
Acked-by: Thomas Langer <thomas.langer@lantiq.com>
Signed-off-by: Shinya Kuribayashi <skuribay@pobox.com>
This define is a board-specific config option and should be
renamed to follow the U-Boot naming convention. Additionally,
add an explaining comment for this option.
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
Acked-by: Thomas Langer <thomas.langer@lantiq.com>
Signed-off-by: Shinya Kuribayashi <skuribay@pobox.com>
Fix style issues and alignments globally. No logical changes.
- Replace C comments with AS line comments where possible
- Use ifndef where possible, rather than if !defined for simplicity
- An instruction executed in a delay slot is now indicated by a leading
space, not by C comment
Signed-off-by: Shinya Kuribayashi <skuribay@pobox.com>
As requested in commit e1390801a3 ([MIPS]
Request for the 'mips_cache_lock()' removal), such feature is no longer
needed for current MIPS implementation of U-Boot, and no one in the tree
uses it for years.
Signed-off-by: Shinya Kuribayashi <skuribay@pobox.com>
All current CPUs and SoCs are based on MIPS32 arch. The complete
code resides in the global arch/mips/cpu directory. This is not
suitable if other MIPS architectures like MIPS64 or Octeon should
be supported in the future.
To achieve this the current CPU code is moved to its own mips32
subdirectory. All MIPS32 boards have to use mips32 as config switch
in board.cfg.
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
Cc: Wolfgang Denk <wd@denx.de>
Cc: Stefan Roese <sr@denx.de>
Cc: Thomas Lange <thomas@corelatus.se>
Cc: Vlad Lungu <vlad.lungu@windriver.com>
Signed-off-by: Shinya Kuribayashi <skuribay@pobox.com>