diff options
Diffstat (limited to 'ports/arm11/gnu/src/tx_timer_interrupt.S')
| -rw-r--r-- | ports/arm11/gnu/src/tx_timer_interrupt.S | 279 |
1 files changed, 279 insertions, 0 deletions
diff --git a/ports/arm11/gnu/src/tx_timer_interrupt.S b/ports/arm11/gnu/src/tx_timer_interrupt.S new file mode 100644 index 00000000..60632a32 --- /dev/null +++ b/ports/arm11/gnu/src/tx_timer_interrupt.S @@ -0,0 +1,279 @@ +@/**************************************************************************/ +@/* */ +@/* 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 */ +@/** */ +@/** Timer */ +@/** */ +@/**************************************************************************/ +@/**************************************************************************/ +@ +@#define TX_SOURCE_CODE +@ +@ +@/* Include necessary system files. */ +@ +@#include "tx_api.h" +@#include "tx_timer.h" +@#include "tx_thread.h" +@ +@ + .arm + +@ +@/* Define Assembly language external references... */ +@ + .global _tx_timer_time_slice + .global _tx_timer_system_clock + .global _tx_timer_current_ptr + .global _tx_timer_list_start + .global _tx_timer_list_end + .global _tx_timer_expired_time_slice + .global _tx_timer_expired + .global _tx_thread_time_slice +@ +@ +@ +@/* Define the 16-bit Thumb mode veneer for _tx_timer_interrupt for +@ applications calling this function from to 16-bit Thumb mode. */ +@ + .text + .align 2 + .thumb + .global $_tx_timer_interrupt + .type $_tx_timer_interrupt,function +$_tx_timer_interrupt: + BX pc @ Switch to 32-bit mode + NOP @ + .arm + STMFD sp!, {lr} @ Save return address + BL _tx_timer_interrupt @ Call _tx_timer_interrupt function + LDMFD sp!, {lr} @ Recover saved return address + BX lr @ Return to 16-bit caller +@ +@ + .text + .align 2 +@/**************************************************************************/ +@/* */ +@/* FUNCTION RELEASE */ +@/* */ +@/* _tx_timer_interrupt ARM11/GNU */ +@/* 6.0.1 */ +@/* AUTHOR */ +@/* */ +@/* William E. Lamie, Microsoft Corporation */ +@/* */ +@/* DESCRIPTION */ +@/* */ +@/* This function processes the hardware timer interrupt. This */ +@/* processing includes incrementing the system clock and checking for */ +@/* time slice and/or timer expiration. If either is found, the */ +@/* interrupt context save/restore functions are called along with the */ +@/* expiration functions. */ +@/* */ +@/* INPUT */ +@/* */ +@/* None */ +@/* */ +@/* OUTPUT */ +@/* */ +@/* None */ +@/* */ +@/* CALLS */ +@/* */ +@/* _tx_thread_time_slice Time slice interrupted thread */ +@/* _tx_timer_expiration_process Timer expiration processing */ +@/* */ +@/* CALLED BY */ +@/* */ +@/* interrupt vector */ +@/* */ +@/* RELEASE HISTORY */ +@/* */ +@/* DATE NAME DESCRIPTION */ +@/* */ +@/* 06-30-2020 William E. Lamie Initial Version 6.0.1 */ +@/* */ +@/**************************************************************************/ +@VOID _tx_timer_interrupt(VOID) +@{ + .global _tx_timer_interrupt + .type _tx_timer_interrupt,function +_tx_timer_interrupt: +@ +@ /* Upon entry to this routine, it is assumed that context save has already +@ been called, and therefore the compiler scratch registers are available +@ for use. */ +@ +@ /* Increment the system clock. */ +@ _tx_timer_system_clock++; +@ + LDR r1, =_tx_timer_system_clock @ Pickup address of system clock + LDR r0, [r1] @ Pickup system clock + ADD r0, r0, #1 @ Increment system clock + STR r0, [r1] @ Store new system clock +@ +@ /* Test for time-slice expiration. */ +@ if (_tx_timer_time_slice) +@ { +@ + LDR r3, =_tx_timer_time_slice @ Pickup address of time-slice + LDR r2, [r3] @ Pickup time-slice + CMP r2, #0 @ Is it non-active? + BEQ __tx_timer_no_time_slice @ Yes, skip time-slice processing +@ +@ /* Decrement the time_slice. */ +@ _tx_timer_time_slice--; +@ + SUB r2, r2, #1 @ Decrement the time-slice + STR r2, [r3] @ Store new time-slice value +@ +@ /* Check for expiration. */ +@ if (__tx_timer_time_slice == 0) +@ + CMP r2, #0 @ Has it expired? + BNE __tx_timer_no_time_slice @ No, skip expiration processing +@ +@ /* Set the time-slice expired flag. */ +@ _tx_timer_expired_time_slice = TX_TRUE; +@ + LDR r3, =_tx_timer_expired_time_slice @ Pickup address of expired flag + MOV r0, #1 @ Build expired value + STR r0, [r3] @ Set time-slice expiration flag +@ +@ } +@ +__tx_timer_no_time_slice: +@ +@ /* Test for timer expiration. */ +@ if (*_tx_timer_current_ptr) +@ { +@ + LDR r1, =_tx_timer_current_ptr @ Pickup current timer pointer address + LDR r0, [r1] @ Pickup current timer + LDR r2, [r0] @ Pickup timer list entry + CMP r2, #0 @ Is there anything in the list? + BEQ __tx_timer_no_timer @ No, just increment the timer +@ +@ /* Set expiration flag. */ +@ _tx_timer_expired = TX_TRUE; +@ + LDR r3, =_tx_timer_expired @ Pickup expiration flag address + MOV r2, #1 @ Build expired value + STR r2, [r3] @ Set expired flag + B __tx_timer_done @ Finished timer processing +@ +@ } +@ else +@ { +__tx_timer_no_timer: +@ +@ /* No timer expired, increment the timer pointer. */ +@ _tx_timer_current_ptr++; +@ + ADD r0, r0, #4 @ Move to next timer +@ +@ /* Check for wraparound. */ +@ if (_tx_timer_current_ptr == _tx_timer_list_end) +@ + LDR r3, =_tx_timer_list_end @ Pickup address of timer list end + LDR r2, [r3] @ Pickup list end + CMP r0, r2 @ Are we at list end? + BNE __tx_timer_skip_wrap @ No, skip wraparound logic +@ +@ /* Wrap to beginning of list. */ +@ _tx_timer_current_ptr = _tx_timer_list_start; +@ + LDR r3, =_tx_timer_list_start @ Pickup address of timer list start + LDR r0, [r3] @ Set current pointer to list start +@ +__tx_timer_skip_wrap: +@ + STR r0, [r1] @ Store new current timer pointer +@ } +@ +__tx_timer_done: +@ +@ +@ /* See if anything has expired. */ +@ if ((_tx_timer_expired_time_slice) || (_tx_timer_expired)) +@ { +@ + LDR r3, =_tx_timer_expired_time_slice @ Pickup address of expired flag + LDR r2, [r3] @ Pickup time-slice expired flag + CMP r2, #0 @ Did a time-slice expire? + BNE __tx_something_expired @ If non-zero, time-slice expired + LDR r1, =_tx_timer_expired @ Pickup address of other expired flag + LDR r0, [r1] @ Pickup timer expired flag + CMP r0, #0 @ Did a timer expire? + BEQ __tx_timer_nothing_expired @ No, nothing expired +@ +__tx_something_expired: +@ +@ + STMDB sp!, {r0, lr} @ Save the lr register on the stack + @ and save r0 just to keep 8-byte alignment +@ +@ /* Did a timer expire? */ +@ if (_tx_timer_expired) +@ { +@ + LDR r1, =_tx_timer_expired @ Pickup address of expired flag + LDR r0, [r1] @ Pickup timer expired flag + CMP r0, #0 @ Check for timer expiration + BEQ __tx_timer_dont_activate @ If not set, skip timer activation +@ +@ /* Process timer expiration. */ +@ _tx_timer_expiration_process(); +@ + BL _tx_timer_expiration_process @ Call the timer expiration handling routine +@ +@ } +__tx_timer_dont_activate: +@ +@ /* Did time slice expire? */ +@ if (_tx_timer_expired_time_slice) +@ { +@ + LDR r3, =_tx_timer_expired_time_slice @ Pickup address of time-slice expired + LDR r2, [r3] @ Pickup the actual flag + CMP r2, #0 @ See if the flag is set + BEQ __tx_timer_not_ts_expiration @ No, skip time-slice processing +@ +@ /* Time slice interrupted thread. */ +@ _tx_thread_time_slice(); +@ + BL _tx_thread_time_slice @ Call time-slice processing +@ +@ } +@ +__tx_timer_not_ts_expiration: +@ + LDMIA sp!, {r0, lr} @ Recover lr register (r0 is just there for + @ the 8-byte stack alignment +@ +@ } +@ +__tx_timer_nothing_expired: +@ +#ifdef __THUMB_INTERWORK + BX lr @ Return to caller +#else + MOV pc, lr @ Return to caller +#endif +@ +@} + |