Commit 3a6c43a7 authored by Atsushi Nemoto's avatar Atsushi Nemoto Committed by Ralf Baechle
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[MIPS] time: Make c0_compare_int_usable faster 



Try increasingly longer time periods starting of at 0x10 cycles.  This
should be fast on hardware and work nicely with emulators.

Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
parent c637fecb

arch/mips/kernel/cevt-r4k.c

+10 −4
Original line number Diff line number Diff line
@@ -179,7 +179,7 @@ static int c0_compare_int_pending(void) 


static int c0_compare_int_usable(void)

{

	const unsigned int delta = 0x300000;

	unsigned int delta;

	unsigned int cnt;



	/*
@@ -192,9 +192,15 @@ static int c0_compare_int_usable(void) 
			return 0;

	}



	for (delta = 0x10; delta <= 0x400000; delta <<= 1) {

		cnt = read_c0_count();

		cnt += delta;

		write_c0_compare(cnt);

		irq_disable_hazard();

		if ((int)(read_c0_count() - cnt) < 0)

		    break;

		/* increase delta if the timer was already expired */

	}



	while ((int)(read_c0_count() - cnt) <= 0)

		;	/* Wait for expiry  */

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