1*4882a593Smuzhiyun/* 2*4882a593Smuzhiyun * (C) Copyright 2000, 2001 3*4882a593Smuzhiyun * Erik Theisen, Wave 7 Optics, etheisen@mindspring.com. 4*4882a593Smuzhiyun * base on code by 5*4882a593Smuzhiyun * Wolfgang Denk, DENX Software Engineering, wd@denx.de. 6*4882a593Smuzhiyun * 7*4882a593Smuzhiyun * SPDX-License-Identifier: GPL-2.0+ 8*4882a593Smuzhiyun */ 9*4882a593Smuzhiyun 10*4882a593Smuzhiyun#include <ppc_asm.tmpl> 11*4882a593Smuzhiyun#include <ppc_defs.h> 12*4882a593Smuzhiyun#include <config.h> 13*4882a593Smuzhiyun#include <watchdog.h> 14*4882a593Smuzhiyun 15*4882a593Smuzhiyun/* 16*4882a593Smuzhiyun * unsigned long long get_ticks(void); 17*4882a593Smuzhiyun * 18*4882a593Smuzhiyun * read timebase as "long long" 19*4882a593Smuzhiyun */ 20*4882a593Smuzhiyun .globl get_ticks 21*4882a593Smuzhiyunget_ticks: 22*4882a593Smuzhiyun1: mftbu r3 23*4882a593Smuzhiyun mftb r4 24*4882a593Smuzhiyun mftbu r5 25*4882a593Smuzhiyun cmp 0,r3,r5 26*4882a593Smuzhiyun bne 1b 27*4882a593Smuzhiyun blr 28*4882a593Smuzhiyun 29*4882a593Smuzhiyun/* 30*4882a593Smuzhiyun * Delay for a number of ticks 31*4882a593Smuzhiyun */ 32*4882a593Smuzhiyun .globl wait_ticks 33*4882a593Smuzhiyunwait_ticks: 34*4882a593Smuzhiyun stwu r1, -16(r1) 35*4882a593Smuzhiyun mflr r0 /* save link register */ 36*4882a593Smuzhiyun stw r0, 20(r1) /* Use r0 or GDB will be unhappy */ 37*4882a593Smuzhiyun stw r14, 12(r1) /* save used registers */ 38*4882a593Smuzhiyun stw r15, 8(r1) 39*4882a593Smuzhiyun mr r14, r3 /* save tick count */ 40*4882a593Smuzhiyun bl get_ticks /* Get start time */ 41*4882a593Smuzhiyun 42*4882a593Smuzhiyun /* Calculate end time */ 43*4882a593Smuzhiyun addc r14, r4, r14 /* Compute end time lower */ 44*4882a593Smuzhiyun addze r15, r3 /* and end time upper */ 45*4882a593Smuzhiyun 46*4882a593Smuzhiyun WATCHDOG_RESET /* Trigger watchdog, if needed */ 47*4882a593Smuzhiyun1: bl get_ticks /* Get current time */ 48*4882a593Smuzhiyun subfc r4, r4, r14 /* Subtract current time from end time */ 49*4882a593Smuzhiyun subfe. r3, r3, r15 50*4882a593Smuzhiyun bge 1b /* Loop until time expired */ 51*4882a593Smuzhiyun 52*4882a593Smuzhiyun lwz r15, 8(r1) /* restore saved registers */ 53*4882a593Smuzhiyun lwz r14, 12(r1) 54*4882a593Smuzhiyun lwz r0, 20(r1) 55*4882a593Smuzhiyun addi r1,r1,16 56*4882a593Smuzhiyun mtlr r0 57*4882a593Smuzhiyun blr 58