esp-open-rtos/core/include/xtensa_ops.h
Alex Stewart 2ecbf1d584 First batch of opensdk additions
Replacements for:
    libmain/misc.o
    libmain/os_cpu_a.o
    libmain/spi_flash.o
    libmain/timers.o
    libmain/uart.o
    libmain/xtensa_context.o
2016-07-06 17:21:34 +10:00

42 lines
1.3 KiB
C

/** xtensa_ops.h
*
* Special macros/etc which deal with Xtensa-specific architecture/CPU
* considerations.
*
* Part of esp-open-rtos
* Copyright (C) 2015 Superhouse Automation Pty Ltd
* BSD Licensed as described in the file LICENSE
*/
#ifndef _XTENSA_OPS_H
#define _XTENSA_OPS_H
/* Read stack pointer to variable.
*
* Note that the compiler will push a stack frame (minimum 16 bytes)
* in the prelude of a C function that calls any other functions.
*/
#define SP(var) asm volatile ("mov %0, a1" : "=r" (var))
/* Read the function return address to a variable.
*
* Depends on the containing function being simple enough that a0 is
* being used as a working register.
*/
#define RETADDR(var) asm volatile ("mov %0, a0" : "=r" (var))
// GCC macros for reading, writing, and exchanging Xtensa processor special
// registers:
#define RSR(var, reg) asm volatile ("rsr %0, " #reg : "=r" (var));
#define WSR(var, reg) asm volatile ("wsr %0, " #reg : : "r" (var));
#define XSR(var, reg) asm volatile ("xsr %0, " #reg : "+r" (var));
// GCC macros for performing associated "*sync" opcodes
#define ISYNC() asm volatile ( "isync" )
#define RSYNC() asm volatile ( "rsync" )
#define ESYNC() asm volatile ( "esync" )
#define DSYNC() asm volatile ( "dsync" )
#endif /* _XTENSA_OPS_H */