/*************************************************************************** * Copyright (c) 2024 Microsoft Corporation * * This program and the accompanying materials are made available under the * terms of the MIT License which is available at * https://opensource.org/licenses/MIT. * * SPDX-License-Identifier: MIT **************************************************************************/ /**************************************************************************/ /**************************************************************************/ /** */ /** ThreadX Component */ /** */ /** Timer */ /** */ /**************************************************************************/ /**************************************************************************/ #ifdef TX_INCLUDE_USER_DEFINE_FILE #include "tx_user.h" #endif .text .align 3 /**************************************************************************/ /* */ /* FUNCTION RELEASE */ /* */ /* _tx_timer_interrupt ARMv8-A */ /* 6.3.0 */ /* 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_timer_expiration_process Timer expiration processing */ /* _tx_thread_time_slice Time slice interrupted thread */ /* */ /* CALLED BY */ /* */ /* interrupt vector */ /* */ /* RELEASE HISTORY */ /* */ /* DATE NAME DESCRIPTION */ /* */ /* 09-30-2020 William E. Lamie Initial Version 6.1 */ /* 10-31-2023 Tiejun Zhou Modified comment(s), added */ /* #include tx_user.h, */ /* resulting in version 6.3.0 */ /* */ /**************************************************************************/ // 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 x1, =_tx_timer_system_clock // Pickup address of system clock LDR w0, [x1, #0] // Pickup system clock ADD w0, w0, #1 // Increment system clock STR w0, [x1, #0] // Store new system clock /* Test for time-slice expiration. */ /* if (_tx_timer_time_slice) { */ LDR x3, =_tx_timer_time_slice // Pickup address of time-slice LDR w2, [x3, #0] // Pickup time-slice CMP w2, #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 w2, w2, #1 // Decrement the time-slice STR w2, [x3, #0] // Store new time-slice value /* Check for expiration. */ /* if (__tx_timer_time_slice == 0) */ CMP w2, #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 x3, =_tx_timer_expired_time_slice // Pickup address of expired flag MOV w0, #1 // Build expired value STR w0, [x3, #0] // Set time-slice expiration flag /* } */ __tx_timer_no_time_slice: /* Test for timer expiration. */ // if (*_tx_timer_current_ptr) // { LDR x1, =_tx_timer_current_ptr // Pickup current timer pointer addr LDR x0, [x1, #0] // Pickup current timer LDR x2, [x0, #0] // Pickup timer list entry CMP x2, #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 x3, =_tx_timer_expired // Pickup expiration flag address MOV w2, #1 // Build expired value STR w2, [x3, #0] // 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 x0, x0, #8 // Move to next timer /* Check for wrap-around. */ // if (_tx_timer_current_ptr == _tx_timer_list_end) LDR x3, =_tx_timer_list_end // Pickup addr of timer list end LDR x2, [x3, #0] // Pickup list end CMP x0, x2 // Are we at list end? BNE __tx_timer_skip_wrap // No, skip wrap-around logic /* Wrap to beginning of list. */ // _tx_timer_current_ptr = _tx_timer_list_start; LDR x3, =_tx_timer_list_start // Pickup addr of timer list start LDR x0, [x3, #0] // Set current pointer to list start __tx_timer_skip_wrap: STR x0, [x1, #0] // Store new current timer pointer // } __tx_timer_done: /* See if anything has expired. */ // if ((_tx_timer_expired_time_slice) || (_tx_timer_expired)) //{ LDR x3, =_tx_timer_expired_time_slice // Pickup addr of expired flag LDR w2, [x3, #0] // Pickup time-slice expired flag CMP w2, #0 // Did a time-slice expire? BNE __tx_something_expired // If non-zero, time-slice expired LDR x1, =_tx_timer_expired // Pickup addr of other expired flag LDR w0, [x1, #0] // Pickup timer expired flag CMP w0, #0 // Did a timer expire? BEQ __tx_timer_nothing_expired // No, nothing expired __tx_something_expired: STP x29, x30, [sp, #-16]! // Save x29 (frame pointer), x30 (link register) /* Did a timer expire? */ // if (_tx_timer_expired) // { LDR x1, =_tx_timer_expired // Pickup addr of expired flag LDR w0, [x1, #0] // Pickup timer expired flag CMP w0, #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 x3, =_tx_timer_expired_time_slice // Pickup addr of time-slice expired LDR w2, [x3, #0] // Pickup the actual flag CMP w2, #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: LDP x29, x30, [sp], #16 // Recover x29, x30 // } __tx_timer_nothing_expired: RET // Return to caller // }