magicse7en b9748e50ea
Xtensa: fix stack overlap coproc_area issue (#118)
In function pxPortInitialiseStack of port.c:
	sp = ( StackType_t * ) ( ( ( UBaseType_t ) ( pxTopOfStack + 1 )  - XT_CP_SIZE - XT_STK_FRMSZ ) & ~0xf );
We assume XT_CP_SIZE is 0xE4, XT_STK_FRMSZ is 0xA0, pxTopOfStack is 0xA0000000, sp is 0x9FFFFE80.
From port.c, we know the frame->a1 as below:
	frame->a1 = ( UBaseType_t ) sp + XT_STK_FRMSZ;  /* physical top of stack frame    */
So frame->a1 is 0x9FFFFF20. Therefore the interrupt stack frame range is 0x9FFFFE80 ~ 0x9FFFFF20.

The coproc_area is: p = ( uint32_t * ) ( ( ( uint32_t ) pxTopOfStack - XT_CP_SIZE ) & ~0xf );
So its value is 0x9FFFFF10. Obviously, the interrupt stack frame overlaps the coproc_area.

Co-authored-by: Carl Lundin <53273776+lundinc2@users.noreply.github.com>
2020-10-26 11:07:32 -07:00
..

Each real time kernel port consists of three files that contain the core kernel
components and are common to every port, and one or more files that are
specific to a particular microcontroller and/or compiler.


+ The FreeRTOS/Source/Portable/MemMang directory contains the five sample
memory allocators as described on the https://www.FreeRTOS.org WEB site.

+ The other directories each contain files specific to a particular
microcontroller or compiler, where the directory name denotes the compiler
specific files the directory contains.



For example, if you are interested in the [compiler] port for the [architecture]
microcontroller, then the port specific files are contained in
FreeRTOS/Source/Portable/[compiler]/[architecture] directory.  If this is the
only port you are interested in then all the other directories can be
ignored.