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-rw-r--r--arch/x86_64/kernel/hpet.c9
1 files changed, 6 insertions, 3 deletions
diff --git a/arch/x86_64/kernel/hpet.c b/arch/x86_64/kernel/hpet.c
index 8cf0b8a13778..b8286968662d 100644
--- a/arch/x86_64/kernel/hpet.c
+++ b/arch/x86_64/kernel/hpet.c
@@ -191,6 +191,7 @@ int hpet_reenable(void)
191 191
192#define TICK_COUNT 100000000 192#define TICK_COUNT 100000000
193#define TICK_MIN 5000 193#define TICK_MIN 5000
194#define MAX_TRIES 5
194 195
195/* 196/*
196 * Some platforms take periodic SMI interrupts with 5ms duration. Make sure none 197 * Some platforms take periodic SMI interrupts with 5ms duration. Make sure none
@@ -198,13 +199,15 @@ int hpet_reenable(void)
198 */ 199 */
199static void __init read_hpet_tsc(int *hpet, int *tsc) 200static void __init read_hpet_tsc(int *hpet, int *tsc)
200{ 201{
201 int tsc1, tsc2, hpet1; 202 int tsc1, tsc2, hpet1, i;
202 203
203 do { 204 for (i = 0; i < MAX_TRIES; i++) {
204 tsc1 = get_cycles_sync(); 205 tsc1 = get_cycles_sync();
205 hpet1 = hpet_readl(HPET_COUNTER); 206 hpet1 = hpet_readl(HPET_COUNTER);
206 tsc2 = get_cycles_sync(); 207 tsc2 = get_cycles_sync();
207 } while (tsc2 - tsc1 > TICK_MIN); 208 if (tsc2 - tsc1 > TICK_MIN)
209 break;
210 }
208 *hpet = hpet1; 211 *hpet = hpet1;
209 *tsc = tsc2; 212 *tsc = tsc2;
210} 213}