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// SPDX-License-Identifier: GPL-2.0
/*
* Precise Delay Loops for ETRAX FS
*
* Copyright (C) 2006 Axis Communications AB.
*
*/
#include <hwregs/reg_map.h>
#include <hwregs/reg_rdwr.h>
#include <hwregs/timer_defs.h>
#include <linux/types.h>
#include <linux/delay.h>
#include <linux/module.h>
/*
* On ETRAX FS, we can check the free-running read-only 100MHz timer
* getting 32-bit 10ns precision, theoretically good for 42.94967295
* seconds. Unsigned arithmetic and careful expression handles
* wrapping.
*/
void cris_delay10ns(u32 n10ns)
{
u32 t0 = REG_RD(timer, regi_timer0, r_time);
while (REG_RD(timer, regi_timer0, r_time) - t0 < n10ns)
;
}
EXPORT_SYMBOL(cris_delay10ns);
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