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/**************************************************************************/
/* Copyright (c) Cadence Design Systems, Inc. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/**************************************************************************/
#include "tx_api.h"
#include "tx_port.h"
#include "xtensa_api.h"
#if XCHAL_HAVE_ISL || XCHAL_HAVE_KSL || XCHAL_HAVE_PSL
#include <xtensa/tie/xt_exception_dispatch.h>
#endif
#if XCHAL_HAVE_XEA3
int32_t xt_sw_intnum = -1;
int32_t xt_timer_intnum = -1;
#endif
/**************************************************************************/
/* */
/* DESCRIPTION */
/* */
/* This function is responsible for any low-level processor */
/* initialization, including setting up interrupt vectors, setting */
/* up a periodic timer interrupt source, saving the system stack */
/* pointer for use in ISR processing later, and finding the first */
/* available RAM memory address for tx_application_define. */
/* It also sets the default heap region for the optional C library. */
/* */
/**************************************************************************/
VOID _tx_initialize_low_level(VOID)
{
extern char _xt_interrupt_stack_top;
extern void _tx_timer_interrupt(void *);
extern void * _tx_thread_system_stack_ptr;
extern void * _tx_initialize_unused_memory;
extern char _end;
#ifdef TX_THREAD_SAFE_CLIB
extern char __stack;
extern void _tx_clib_init(void);
#endif
#if XCHAL_CP_NUM > 0
extern void _xt_coproc_init(void);
extern void _xt_coproc_exc(XtExcFrame * fp);
#endif
#ifdef TX_ENABLE_STACK_CHECKING
extern VOID _tx_xtensa_stack_error_handler(TX_THREAD * thread);
#endif
#if XCHAL_HAVE_XEA3
extern void xt_sched_handler(void * arg);
int32_t i;
#endif
TX_INTERRUPT_SAVE_AREA
/* Disable interrupts - don't want any that interact with ThreadX yet. */
TX_DISABLE
/* Suppress compiler warning about set but not used variable. */
(void) interrupt_save;
/*
Disable stack limit checking if present. Whatever was set up earlier
is not going to work for us.
*/
#if XCHAL_HAVE_KSL
XT_WSR_KSL(0);
#endif
#if XCHAL_HAVE_ISL
XT_WSR_ISL(0);
#endif
/* Save the system stack pointer. */
_tx_thread_system_stack_ptr = &(_xt_interrupt_stack_top);
/* Save the first available memory address. */
_tx_initialize_unused_memory = (void *)(((UINT)&_end + 15) & ~0xF);
#ifdef TX_THREAD_SAFE_CLIB
/*
Pre-allocate default memory region for the C library heap.
Bisect the region from first available memory to end of system memory,
align to 16 byte boundary, and allocate the heap in the upper half.
*/
_tx_clib_heap_end = &(__stack);
_tx_clib_heap_start =
(void *)(((UINT)_tx_initialize_unused_memory/2 + (UINT)_tx_clib_heap_end/2) & ~0xF);
#endif
#if XCHAL_CP_NUM > 0
/*
Initialize co-processor management for threads. Leave CPENABLE alone.
This is called from a normal Xtensa single-threaded run-time environment
before multi-threading has commenced. All co-processors are enabled.
It is important NOT to clear CPENABLE yet because tx_application_define()
is user code which might use a co-processor. The co-processor exception
handler does not expect to be called outside a thread.
*/
_xt_coproc_init();
#if XCHAL_HAVE_XEA3
/* Install the coprocessor exception handler. */
xt_set_exception_handler(EXCCAUSE_CP_DISABLED, _xt_coproc_exc);
#endif
#endif
#if XCHAL_HAVE_XEA3
/* Select a software interrupt to use for scheduling. */
for (i = 0; i < XCHAL_NUM_INTERRUPTS; i++) {
if ((Xthal_inttype[i] == XTHAL_INTTYPE_SOFTWARE) && (Xthal_intlevel[i] == 1)) {
xt_sw_intnum = i;
break;
}
}
if (xt_sw_intnum == -1) {
__asm__ volatile ("break 1, 1");
}
/* Set the interrupt handler and enable the interrupt. */
xt_set_interrupt_handler(xt_sw_intnum, xt_sched_handler, 0);
xt_interrupt_enable(xt_sw_intnum);
#endif
#ifndef TX_NO_TIMER
/* Compute tick divisor if clock freq is not compile-time constant. */
#ifndef XT_CLOCK_FREQ
xt_tick_divisor_init();
#endif
/* Set up the periodic tick timer (assume enough time to complete init). */
#ifdef XT_CLOCK_FREQ
XT_WSR_CCOMPARE(XT_RSR_CCOUNT() + XT_TICK_DIVISOR);
#else
XT_WSR_CCOMPARE(XT_RSR_CCOUNT() + xt_tick_divisor);
#endif
#if XCHAL_HAVE_XEA3
xt_timer_intnum = XT_TIMER_INTNUM;
xt_set_interrupt_handler(xt_timer_intnum, _tx_timer_interrupt, 0);
#endif
/* Enable the timer interrupt at the device level. */
xt_interrupt_enable(XT_TIMER_INTNUM);
#endif /* TX_NO_TIMER */
/* Initialize C library thread safety support. */
#ifdef TX_THREAD_SAFE_CLIB
_tx_clib_init();
#endif
/* Install stack overflow notification callback. */
#ifdef TX_ENABLE_STACK_CHECKING
tx_thread_stack_error_notify(_tx_xtensa_stack_error_handler);
#endif
}
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