/* * Copyright (c) 2016 Cadence Design Systems, Inc. * SPDX-License-Identifier: Apache-2.0 */ /* * RTOS-SPECIFIC INFORMATION FOR XTENSA RTOS ASSEMBLER SOURCES * (FreeRTOS Port) * * This header is the primary glue between generic Xtensa RTOS support * sources and a specific RTOS port for Xtensa. It contains definitions * and macros for use primarily by Xtensa assembly coded source files. * * Macros in this header map callouts from generic Xtensa files to specific * RTOS functions. It may also be included in C source files. * * Xtensa RTOS ports support all RTOS-compatible configurations of the Xtensa * architecture, using the Xtensa hardware abstraction layer (HAL) to deal * with configuration specifics. * * Should be included by all Xtensa generic and RTOS port-specific sources. */ #ifndef XTENSA_RTOS_H #define XTENSA_RTOS_H #ifdef __ASSEMBLER__ #include #else #include #endif #include #include #include /* * Convert FreeRTOSConfig definitions to XTENSA definitions. * However these can still be overridden from the command line. */ #ifndef XT_SIMULATOR #if CONFIG_SIMULATOR_XTENSA #define XT_SIMULATOR 1 /* Simulator mode */ #endif #endif #ifndef XT_BOARD #if CONFIG_BOARD_XTENSA #define XT_BOARD 1 /* Board mode */ #endif #endif #ifndef XT_TIMER_INDEX #if defined configXT_TIMER_INDEX /* Index of hardware timer to be used */ #define XT_TIMER_INDEX configXT_TIMER_INDEX #endif #endif #ifndef XT_INTEXC_HOOKS #if configXT_INTEXC_HOOKS #define XT_INTEXC_HOOKS 1 /* Enables exception hooks */ #endif #endif #if (!XT_SIMULATOR) && (!XT_BOARD) #error Either XT_SIMULATOR or XT_BOARD must be defined. #endif /* * Name of RTOS (for messages). */ #define XT_RTOS_NAME Zephyr /* * Define for enabling RTOS specific code. Enable only one of below lines. */ #define XT_RTOS_IS_ZEPHYR_OS 1 #undef XT_RTOS_IS_FREE_RTOS /* * Check some Xtensa configuration requirements and report error if not met. * Error messages can be customize to the RTOS port. */ #if !XCHAL_HAVE_XEA2 #error "Zephyr/Xtensa requires XEA2 (exception architecture 2)." #endif /* * RTOS CALLOUT MACROS MAPPED TO RTOS PORT-SPECIFIC FUNCTIONS. * * Define callout macros used in generic Xtensa code to interact with the RTOS. * The macros are simply the function names for use in calls from assembler * code. * Some of these functions may call back to generic functions in * xtensa_context.h . */ /* * Inform RTOS of entry into an interrupt handler that will affect it. * Allows RTOS to manage switch to any system stack and count nesting level. * Called after minimal context has been saved, with interrupts disabled. * RTOS port can call0 _xt_context_save to save the rest of the context. * May only be called from assembly code by the 'call0' instruction. */ #define XT_RTOS_INT_ENTER _zxt_int_enter /* * Inform RTOS of completion of an interrupt handler, and give control to * RTOS to perform thread/task scheduling, switch back from any system stack * and restore the context, and return to the exit dispatcher saved in the * stack frame at XT_STK_EXIT. RTOS port can call0 _xt_context_restore * to save the context saved in XT_RTOS_INT_ENTER via _xt_context_save, * leaving only a minimal part of the context to be restored by the exit * dispatcher. This function does not return to the place it was called from. * May only be called from assembly code by the 'call0' instruction. */ #define XT_RTOS_INT_EXIT _zxt_int_exit /* * Inform RTOS of the occurrence of a tick timer interrupt. * If RTOS has no tick timer, leave XT_RTOS_TIMER_INT undefined. * May be coded in or called from C or assembly, per ABI conventions. * RTOS may optionally define XT_TICK_PER_SEC in its own way (eg. macro). */ #define XT_RTOS_TIMER_INT _zxt_timer_int #define XT_TICK_PER_SEC CONFIG_SYS_CLOCK_TICKS_PER_SEC /* * Return in a15 the base address of the co-processor state save area for the * thread that triggered a co-processor exception, or 0 if no thread was * running. The state save area is structured as defined in xtensa_context.h * and has size XT_CP_SIZE. Co-processor instructions should only be used in * thread code, never in interrupt handlers or the RTOS kernel. May only be * called from assembly code and by the 'call0' instruction. A result of 0 * indicates an unrecoverable error. * * The implementation may use only a2-4, a15 (all other regs must be * preserved). */ #define XT_RTOS_CP_STATE _zxt_task_coproc_state /* * HOOKS TO DYNAMICALLY INSTALL INTERRUPT AND EXCEPTION HANDLERS PER LEVEL. * * This Xtensa RTOS port provides hooks for dynamically installing exception * and interrupt handlers to facilitate automated testing where each test case * can install its own handler for user exceptions and each interrupt priority * (level). This consists of an array of function pointers indexed by interrupt * priority, with index 0 being the user exception handler hook. Each entry in * the array is initially 0, and may be replaced by a function pointer of type * XT_INTEXC_HOOK. A handler may be uninstalled by installing 0. * * The handler for low and medium priority obeys ABI conventions so may be * coded in C. For the exception handler, the cause is the contents of the * EXCCAUSE reg, and the result is -1 if handled, else the cause (still needs * handling). For interrupt handlers, the cause is a mask of pending enabled * interrupts at that level, and the result is the same mask with the bits for * the handled interrupts cleared (those not cleared still need handling). This * allows a test case to either pre-handle or override the default handling for * the exception or interrupt level (see xtensa_vectors.S). * * High priority handlers (including NMI) must be coded in assembly, are always * called by 'call0' regardless of ABI, must preserve all registers except a0, * and must not use or modify the interrupted stack. The hook argument 'cause' * is not passed and the result is ignored, so as not to burden the caller * with saving and restoring a2 (it assumes only one interrupt per level - see * the discussion in high priority interrupts in xtensa_vectors.S). The handler * therefore should be coded to prototype 'void h(void)' even though it plugs * into an array of handlers of prototype 'unsigned h(unsigned)'. * * To enable interrupt/exception hooks, compile the RTOS with * '-DXT_INTEXC_HOOKS'. */ #define XT_INTEXC_HOOK_NUM (1 + XCHAL_NUM_INTLEVELS + XCHAL_HAVE_NMI) #ifndef __ASSEMBLER__ typedef unsigned int (*XT_INTEXC_HOOK)(unsigned int cause); extern volatile XT_INTEXC_HOOK _xt_intexc_hooks[XT_INTEXC_HOOK_NUM]; #endif /* * CONVENIENCE INCLUSIONS. * * Ensures RTOS specific files need only include this one Xtensa-generic * header. These headers are included last so they can use the RTOS * definitions above. */ #include "xtensa_context.h" #ifdef XT_RTOS_TIMER_INT #include "xtensa_timer.h" #endif #endif /* XTENSA_RTOS_H */