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| /*
| * (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
|
|
