diff options
Diffstat (limited to 'ports/arm11/gnu/src/tx_thread_schedule.S')
| -rw-r--r-- | ports/arm11/gnu/src/tx_thread_schedule.S | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/ports/arm11/gnu/src/tx_thread_schedule.S b/ports/arm11/gnu/src/tx_thread_schedule.S new file mode 100644 index 00000000..09692e98 --- /dev/null +++ b/ports/arm11/gnu/src/tx_thread_schedule.S @@ -0,0 +1,187 @@ +@/**************************************************************************/ +@/* */ +@/* Copyright (c) Microsoft Corporation. All rights reserved. */ +@/* */ +@/* This software is licensed under the Microsoft Software License */ +@/* Terms for Microsoft Azure RTOS. Full text of the license can be */ +@/* found in the LICENSE file at https://aka.ms/AzureRTOS_EULA */ +@/* and in the root directory of this software. */ +@/* */ +@/**************************************************************************/ +@ +@ +@/**************************************************************************/ +@/**************************************************************************/ +@/** */ +@/** ThreadX Component */ +@/** */ +@/** Thread */ +@/** */ +@/**************************************************************************/ +@/**************************************************************************/ +@ +@ +@#define TX_SOURCE_CODE +@ +@ +@/* Include necessary system files. */ +@ +@#include "tx_api.h" +@#include "tx_thread.h" +@#include "tx_timer.h" +@ +#ifdef TX_ENABLE_FIQ_SUPPORT +ENABLE_INTS = 0xC0 @ IRQ & FIQ Interrupts enabled mask +#else +ENABLE_INTS = 0x80 @ IRQ Interrupts enabled mask +#endif +@ +@ + .global _tx_thread_execute_ptr + .global _tx_thread_current_ptr + .global _tx_timer_time_slice + .global _tx_execution_thread_enter +@ +@ +@/* Define the 16-bit Thumb mode veneer for _tx_thread_schedule for +@ applications calling this function from to 16-bit Thumb mode. */ +@ + .text + .align 2 + .global $_tx_thread_schedule + .type $_tx_thread_schedule,function +$_tx_thread_schedule: + .thumb + BX pc @ Switch to 32-bit mode + NOP @ + .arm + STMFD sp!, {lr} @ Save return address + BL _tx_thread_schedule @ Call _tx_thread_schedule function + LDMFD sp!, {lr} @ Recover saved return address + BX lr @ Return to 16-bit caller +@ +@ + .text + .align 2 +@/**************************************************************************/ +@/* */ +@/* FUNCTION RELEASE */ +@/* */ +@/* _tx_thread_schedule ARM11/GNU */ +@/* 6.0.1 */ +@/* AUTHOR */ +@/* */ +@/* William E. Lamie, Microsoft Corporation */ +@/* */ +@/* DESCRIPTION */ +@/* */ +@/* This function waits for a thread control block pointer to appear in */ +@/* the _tx_thread_execute_ptr variable. Once a thread pointer appears */ +@/* in the variable, the corresponding thread is resumed. */ +@/* */ +@/* INPUT */ +@/* */ +@/* None */ +@/* */ +@/* OUTPUT */ +@/* */ +@/* None */ +@/* */ +@/* CALLS */ +@/* */ +@/* None */ +@/* */ +@/* CALLED BY */ +@/* */ +@/* _tx_initialize_kernel_enter ThreadX entry function */ +@/* _tx_thread_system_return Return to system from thread */ +@/* _tx_thread_context_restore Restore thread's context */ +@/* */ +@/* RELEASE HISTORY */ +@/* */ +@/* DATE NAME DESCRIPTION */ +@/* */ +@/* 06-30-2020 William E. Lamie Initial Version 6.0.1 */ +@/* */ +@/**************************************************************************/ +@VOID _tx_thread_schedule(VOID) +@{ + .global _tx_thread_schedule + .type _tx_thread_schedule,function +_tx_thread_schedule: +@ +@ /* Enable interrupts. */ +@ + MRS r2, CPSR @ Pickup CPSR + BIC r0, r2, #ENABLE_INTS @ Clear the disable bit(s) + MSR CPSR_cxsf, r0 @ Enable interrupts +@ +@ /* Wait for a thread to execute. */ +@ do +@ { + LDR r1, =_tx_thread_execute_ptr @ Address of thread execute ptr +@ +__tx_thread_schedule_loop: +@ + LDR r0, [r1] @ Pickup next thread to execute + CMP r0, #0 @ Is it NULL? + BEQ __tx_thread_schedule_loop @ If so, keep looking for a thread +@ +@ } +@ while(_tx_thread_execute_ptr == TX_NULL); +@ +@ /* Yes! We have a thread to execute. Lockout interrupts and +@ transfer control to it. */ +@ + MSR CPSR_cxsf, r2 @ Disable interrupts +@ +@ /* Setup the current thread pointer. */ +@ _tx_thread_current_ptr = _tx_thread_execute_ptr; +@ + LDR r1, =_tx_thread_current_ptr @ Pickup address of current thread + STR r0, [r1] @ Setup current thread pointer +@ +@ /* Increment the run count for this thread. */ +@ _tx_thread_current_ptr -> tx_thread_run_count++; +@ + LDR r2, [r0, #4] @ Pickup run counter + LDR r3, [r0, #24] @ Pickup time-slice for this thread + ADD r2, r2, #1 @ Increment thread run-counter + STR r2, [r0, #4] @ Store the new run counter +@ +@ /* Setup time-slice, if present. */ +@ _tx_timer_time_slice = _tx_thread_current_ptr -> tx_thread_time_slice; +@ + LDR r2, =_tx_timer_time_slice @ Pickup address of time-slice + @ variable + LDR sp, [r0, #8] @ Switch stack pointers + STR r3, [r2] @ Setup time-slice +@ +@ /* Switch to the thread's stack. */ +@ sp = _tx_thread_execute_ptr -> tx_thread_stack_ptr; +@ +#ifdef TX_ENABLE_EXECUTION_CHANGE_NOTIFY +@ +@ /* Call the thread entry function to indicate the thread is executing. */ +@ + BL _tx_execution_thread_enter @ Call the thread execution enter function +#endif +@ +@ /* Determine if an interrupt frame or a synchronous task suspension frame +@ is present. */ +@ + LDMIA sp!, {r0, r1} @ Pickup the stack type and saved CPSR + CMP r0, #0 @ Check for synchronous context switch + MSRNE SPSR_cxsf, r1 @ Setup SPSR for return + LDMNEIA sp!, {r0-r12, lr, pc}^ @ Return to point of thread interrupt + LDMIA sp!, {r4-r11, lr} @ Return to thread synchronously + MSR CPSR_cxsf, r1 @ Recover CPSR +#ifdef __THUMB_INTERWORK + BX lr @ Return to caller +#else + MOV pc, lr @ Return to caller +#endif +@ +@} +@ + |