In most places, picolibc and newlib are the same, so use
the existing newlib code when compiling with picolibc.
Signed-off-by: Keith Packard <keithp@keithp.com>
The function would always return `true` after early boot, so it
is not very useful for applications.
Now it will only (but always) return true when we woke from Deep Sleep
*after* early boot. This makes it behave the same ways as the function
of the same name on SAME54.
Rename the existing function to cpu_backup_ram_is_initialized() to better
match it's semantics.
For better compatibility copy most of cortexm_base.ld
and use the same section names.
Only interrupt stacks and the two additional (currently unused)
heap sections are different between the two now.
lpc23xx has 2k of battery RAM that is retained in Deep Power Down mode.
To not overwrite that data it must only be initialized on Power On Reset.
However, RSIR looks the same when waking up from Deep Power Down as it does
on the power-on case.
So use 4 bytes of the backup RAM to keep a signature that is only valid if
memory was retained (no power-on Reset).
A small change to the linker script is required so two sections can be
placed into flash.
puf_sram only relies on an uninitialized chunk of memory.
This means to enable it we just have to hook up puf_sram_init().
All memory after __bss_end should be uninitialized at startup, so
just use that.
- split up interrupt vector code from bootloader.c to vectors.c
- moved bootloader.c to arm7_init.c
- Use consistent naming:
- use lower case for everything but preprocessor stuff
- ISRs now named isr_foo()
