As a preparation to ARCv2 port submission we rename "arc700" folder to
"arcv1" which stands for ARCv1 ISA also known as ARCompact.
This will allow us to add more flavours of binary-compatible ARCv1 CPUs
like ARC600 if needed later on and all required ARCv2 CPUs (which are
binary incompatible with ARCv1) in "arcv2" folder in subsequent commits.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Igor Guryanov <guryanov@synopsys.com>
"reset.c" and "cpu.c" have no architecture-specific code at all.
Others are applicable to either ARC CPU.
This change is a preparation to submission of ARCv2 architecture port.
Even though ARCv1 and ARCv2 ISAs are not binary compatible most of
built-in modules still have the same programming model - AUX registers
are mapped in the same addresses and hold the same data (new featues
extend existing ones).
So only low-level assembly code (start-up, interrupt handlers) is left
as CPU(actually ISA)-specific. This significantyl simplifies maintenance
of multiple CPUs/ISAs.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Igor Guryanov <guryanov@synopsys.com>
Even though existing implementation works fine in preparation to
submission of ARCv2 architecture we need this change.
In case of ARCv2 interrupt vector table consists of just addresses
of corresponding handlers. And if those addresses will be in .text
section then assembler will encode them as everything in .text section
as middle-endian and then on real execution CPU will read swapped
addresses and will jump into the wild.
Once introduced new section is situated so .text section remains the
first which allows us to use common linker option for linking everything
to a specified CONFIG_SYS_TEXT_BASE.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Igor Guryanov <guryanov@synopsys.com>
Depending on MMU presence in CPU there're differences in HW behavior.
For example address of instruction that caused exception is put in
ECR register if MMU exists and in ERET register otherwise.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Igor Guryanov <guryanov@synopsys.com>
To disable interrupts we need to reset corresponding flags in STATUS32
register. For this we need to OR flags for interrupts level1 and level2
and then AND with current value in STATUS32.
Before that implementation was incorrect.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Igor Guryanov <guryanov@synopsys.com>
Exception cause register (ECR) contains value that describes a reason
for exception that has happened. This helps a lot to figure-out what
went wrong.
Now we print this register contents when dumping registers.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Igor Guryanov <guryanov@synopsys.com>
Some cache operations ({i|d}cache_{enable|disable|status} or
flush_dcache_all) are built and used even if CONFIG_SYS_{I|D}CACHE_OFF
is set.
This is required for force disable of caches on early boot.
What if something was executed before U-boot and enabled caches
(low-level bootloaders, previously run kernel etc.)?
But if CPU doesn't really have caches any attempt to access
cache-related AUX registers triggers instruction error exception.
So for convenience we'll try to avoid exceptions by checking if CPU
actually has caches (we check separately data and instruction cache
existence) at all.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Igor Guryanov <guryanov@synopsys.com>
