According to: https://gcc.gnu.org/onlinedocs/gcc-6.2.0/gcc/ARM-Function-Attributes.html
"Only basic asm statements can safely be included in naked functions (see Basic
Asm). While using extended asm or a mixture of basic asm and C code may appear
to work, they cannot be depended upon to work reliably and are not supported."
SHCSR and DFSR are only implement on ARMv6 if the "Debug extension" is
implemented, but that's pretty much everywhere, so allow access to the
defines.
Signed-off-by: Karl Palsson <karlp@tweak.net.au>
This is more in line with the actual hardware (u32 registers), and will still
work if PRIMASK or FAULTMASK ever have more than 1 bit defined.
The functions cm_is_masked_interrupts() and cm_is_masked_faults() are
unchanged, since returning 'bool' fits with the function naming.
Fixes most of github issue #475. What remains "unfixed" is the absence
of functions to simply 'get' the u32 value of PRIMASK and FAULTMASK registers.
The MPU RASR AP table has a duplicate entries for Privileged ReadOnly
and Usermode ReadOnly, in the source ARM document (Cortex M3 TRM)
Remove the duplicate here.
The MPU RASR Shareable, Bufferable and Cacheable bits are all individual
bits, and none of the existing defines appear to even match the ARM
documentation. Remove them, but leave the definitions of the bit
positions.
Reported by MightyPork on IRC
This adds the "volatile" keyword to all the inline assembly. gcc docs say "You can prevent an asm instruction from being deleted by writing the keyword volatile after the asm.". Testing (see comments of github issue #475) shows that indeed gcc can remove some inline asm, in at least this situation:
-multiple calls to cm_is_masked_interrupts() in the same scope/context
- -Os or -O2 optimization
This is problem because the value of PRIMASK could change between two calls to cm_is_masked_interrupts().
Adding the volatile keyword fixes this, and probably costs less than adding a full barrier (like adding "memory" to the clobber list).
These prototypes affect functions defined by application code. Only
the implementations in libopencm3 are supposed to be weak; the
functions in application code should definitely not be. Otherwise,
you'll end up with two weak symbols being linked together, and
it's luck as to which one the linker picks.
All the macro arguments that are user supplied, or potentially, wrap properly
in () as good practice.
Probably missed one or two, and a lot of them are possibly unnecessary, but
it's straightforward to just do it always.
Fixes github issue #321
The MPU is an implementation option available for both ARMv6-M and ARMv7-M.
Remove poorly merged code that attempted to include this only for cortex m0+.
Added doxygen, updated the definitions of the RBAR register, (though if you're
really using this periperhal, you should be looking at the ref man for further
information)
Reported-by: forrestv on irc.
While there might be other places that are missing this include, this
particular file is clearly missing them, and has resulted in a few separate bug
reports. Fix it right now, in the name of continuous improvement.
Fixes#310 and #427
When compiling with all warnings enabled, some defines can lead to
warning due to missing unsigned type suffix:
warning: integer overflow in expression [-Woverflow]
This fix should not affected behavior at all, since calculation with
such overflows lead to the same actual address when writing to that
location. However, it makes the warning disappear and also defines
the right data type for a memory location.
ITM Stimulus ports need to be accessible with different sizes
The amount of data written out is determined by the size of the write.
Writing a full 32 bit value when you only need 8 for printf() style
substantially reduces the available bandwidth of the SWO
Note: this is an API change for doing 32bit writes.
Old:
ITM_STIM[stimulus_port] = value
New:
ITM_STIM32(stimulus_port) = value
This api is much more in common with some of the other registers that
behave this way. As there's very little (if any) code already using
this API, it's a good time to fix it permanently.
Remove misleading ITM register definitions
ITM_SSPSR is the supported parallel trace size, in _bits_
ITM_CSPSR is in _bits_ as well. There's really no advantage in even
having these sorts of definitions in libopencm3, as these settings are
normally controlled from the debugger side, not the target itself.
Lock and lock status register definitions were added, as per ARM:
"For ARMv7-M, the component ID registers are required for the ROM table,
and the CoreSight management lock access mechanism is defined for the
DWT, ITM, FPB and TPIU blocks."
Harald Welte
Jacob Potter