| /* |
| * (C) Copyright 2000, 2001 |
| * Erik Theisen, Wave 7 Optics, etheisen@mindspring.com. |
| * base on code by |
| * Wolfgang Denk, DENX Software Engineering, wd@denx.de. |
| * |
| * SPDX-License-Identifier: GPL-2.0+ |
| */ |
| |
| #include <ppc_asm.tmpl> |
| #include <ppc_defs.h> |
| #include <config.h> |
| #include <watchdog.h> |
| |
| /* |
| * unsigned long long get_ticks(void); |
| * |
| * read timebase as "long long" |
| */ |
| .globl get_ticks |
| get_ticks: |
| 1: mftbu r3 |
| mftb r4 |
| mftbu r5 |
| cmp 0,r3,r5 |
| bne 1b |
| blr |
| |
| /* |
| * Delay for a number of ticks |
| */ |
| .globl wait_ticks |
| wait_ticks: |
| stwu r1, -16(r1) |
| mflr r0 /* save link register */ |
| stw r0, 20(r1) /* Use r0 or GDB will be unhappy */ |
| stw r14, 12(r1) /* save used registers */ |
| stw r15, 8(r1) |
| mr r14, r3 /* save tick count */ |
| bl get_ticks /* Get start time */ |
| |
| /* Calculate end time */ |
| addc r14, r4, r14 /* Compute end time lower */ |
| addze r15, r3 /* and end time upper */ |
| |
| WATCHDOG_RESET /* Trigger watchdog, if needed */ |
| 1: bl get_ticks /* Get current time */ |
| subfc r4, r4, r14 /* Subtract current time from end time */ |
| subfe. r3, r3, r15 |
| bge 1b /* Loop until time expired */ |
| |
| lwz r15, 8(r1) /* restore saved registers */ |
| lwz r14, 12(r1) |
| lwz r0, 20(r1) |
| addi r1,r1,16 |
| mtlr r0 |
| blr |