From 2478a549b9f64c50310da41c861b8f86fdea2861 Mon Sep 17 00:00:00 2001 From: Josh Rahm Date: Tue, 24 Nov 2020 00:38:09 -0700 Subject: Add new system for startup. Now instead of init() and main() being responsible for all initialization, individual modules can link in their own initialization routines. There are 7 levels for these initializiation routines. So far these are how the levels are defined level 0 - Here the world is dark. Nothing is initialized. This level is responsible for initializing the system clock. level 1 - The system clock has been configured, but nothing else. Not even global variables. This level is responsible for loading the data sections from flash and clearing the .bss section. level 2 - USART2 is enabled and set to be the main kernel logging vehicle. From this point on klogf(...) can be used. level 3 - The NVIC is reset to point to the flash. From this point on interrupts can be received. I expect this is where most core initialization routines will take place levels 4 to 7 - User initializiation levels. main - main() is called after all 8 initialization levels have executed, so in a sense main() is like a 9th initialization level, except that there is can be only one main() routine whereas there can be multiple initalization routines per level. --- 02-usart/include/kern/log.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) create mode 100644 02-usart/include/kern/log.h (limited to '02-usart/include/kern/log.h') diff --git a/02-usart/include/kern/log.h b/02-usart/include/kern/log.h new file mode 100644 index 0000000..5e49def --- /dev/null +++ b/02-usart/include/kern/log.h @@ -0,0 +1,12 @@ +#ifndef LOG_H_ +#define LOG_H_ + +/* + * Defines logging capabilities. This logging unit will enable logging on + * the systems main USART output. + */ + +/** Similar to fprintf, but with a stripped-down format-string DSL. */ +void klogf(const char* fmt, ...); + +#endif -- cgit