The thread_yield_higher is a normal functions. However it has a non
regular return instruction which is useless. This remove the useless
return on thread_yield_higher to save flash bytes.
Signed-off-by: Gerson Fernando Budke <nandojve@gmail.com>
The avr8_state variable uses bit operation to set/clear the state. This
rework avr8_state to use increment/decrement instead. It introduce the
use of General Purpose IO Register 1 (GPIOR1) when available.
This is a preparation for future scheduling and irq optimizations.
Signed-off-by: Gerson Fernando Budke <nandojve@gmail.com>
The current context switch and thread stack init don't have a generic
way to save/restore registers for all AVR-8 variations. This add
defines to check flash/data sizes and rework:
- thread_stack_init
- avr8_context_save
- avr8_context_restore
The new implementation add missing RAMP D/X/Y registers that are used
by XMEGA variations.
The rules to add EIND, RAMP(D,X,Y,Z) register are:
- EIND must be added if device have more than 128k flash. This means,
device can access more than 64k words in flash.
- RAMP D/X/Y must be added if device have or can address more than
64k data.
- RAMPZ must be added if device can address more than 64k bytes of
flash or data.
With above rules there is no necessity to check by device because it is
mandatory the registers for those MCU variations.
Signed-off-by: Gerson Fernando Budke <nandojve@gmail.com>
Split atmega_common code into avr8_common folder. This moves common
avr8 code to be used for all avr8 variants: tiny, mega and xmega.
Signed-off-by: Gerson Fernando Budke <nandojve@gmail.com>
