- create linker section for those <module>Initialize()
- later this list will incorporate parameters as well. (this probably will be more a OP feature to swap/remove/delete module on the fly.
- this is not done at compile time anymore by Makefile.
- this will allow us to have control on the module start at run-time (not implemented but build the ground for it).
- this simplify the startup (Part of code re-org).
- this change does not affect sim_posix and win32 (since they don't need that)
- ensure it's compiling for PiOS.posix
- port to PiOS.win32 but not tested (not compiled)
- tested on CC
- compile on OP.
- this free ~200 bytes.
- current avalable bytes (is we keep the same remaining bytes on the stack than before) is easily passed the 1.2Ko mark on CC with new gcc (4.5.2)
- this does not include init-reorg for each module (I still think more can be freed)
CAREFULL: the heap section need to be the last section in RAM to avoid overwritting data...
Tested with GCC 4.5.2 this gives 1K of free bytes usable in heap right away (including the 200 bytes saved just by using the new gcc).
This does not include any code re-org yet!
- switch back to MSP stack before starting the scheduler so that the sheduler can use the IRQ stack (when/if needed).
- call the C portable function in heap1 to claim some stack back (the number to claim is taken from linker file).
- start the scheduler from reset vector (I move this here from main because it make sense to not go back to C (so that I don't need to copy the rolled stack in case the sheduler returns). This make it more clean.
- Also I have added the call to the mem manager if sheduler return. that way, we don't reset indefinitely if memory runs out. We will go to this handler and figure things out (right now, it's just looping but at least not rebooting. Probably trap NMI would be better (later improvement).
The part missing for this part is the weak attribute for the function in heap1.c so that we don't have to update everything with empty stub.
I think the weak atrribute for C function called in assembly is arch dependent so I am not sure if this is possible (will look into it, maybe somebody outthere nows).
Right now, it's heap1 dependent and won't work with heap2. I will clean that up the next couple of days.
I did some test and it looks good.
this is without init code re-organization so we don't free as much as we will be it's good starts.
This compile with sim_posix (since it does not affect portable code) so this is really clean.
I only tested this with CC. I will port it for OP when I will work on heap2.
- use IRQStack for ISRs (at begening of SRAM) (let's call it the irq stack)
- use end of heap for stack needed during initialization (let's call it the init stack).
- the systemStats in GCS indicate the remaining bytes in the IRQ stack (this is realy usefull to monitor our (nested) IRQs.
This is the base ground to provide as much memory as possible available at task creation time.
Next step is to re-organize the initialization in order to move all the init out of the thread's stacks onto the init stack.
This will provide as much memory as possible available at task creation time.
Basically the stack during initialization will be destroyed once the scheduler starts and dynamic alloc are made (since the init stack is at the end of the heap). We will need to make sure we don't clobber the heap during initialization otherwise this will lead to stack corruption.
The USE_BOOTLOADER compile flag was only being used
to determine where the ISR vector table was located.
Provide this explicitly from the linker since it knows
exactly where it is putting the ISR vector table.
The board info blob is stored in the last 128 bytes of the
bootloader's flash bank. You can access this data from the
application firmware like this:
#include <pios_board_info.h>
if (pios_board_info_blob.magic == PIOS_BOARD_INFO_BLOB_MAGIC) {
/* Check some other fields */
}
DO NOT link pios_board_info.c into your application firmware.
Only bootloaders should provide the content for the board info
structure. The application firmware is only a user of the data.
This change is made up of a number of tightly coupled
changes:
- Deprecate the use of the USE_BOOTLOADER command-line
option. It is now hard-coded in each Makefile.
Overriding it on the command line is not allowed.
- Split apart the memory declaration and the section
declaration in all linker files (*_memory.ld and
*_sections.ld).
- Describe the split between bootloader and app sections
of flash in each board's _memory.ld file.
- Change program target to selectively erase flash so
that the installed bootloader is preserved across even
JTAG programming operations.
- All elf files are built with debug symbols and are not
stripped. This should help debugging with gdb. The
images programmed on the boards are all .bin files now
which do not include symbols.
