From: Takashi Iwai Subject: x86: workaround for mccreary HPET read problem Patch-mainline: not yet References: bnc#433746 On mccreacy platform, the read of HPET CMP register seems not updated immediately after the write and returns the previous value instead. A workaround is to read the register twice. Signed-off-by: Takashi Iwai --- --- arch/x86/kernel/hpet.c | 1 + 1 file changed, 1 insertion(+) --- a/arch/x86/kernel/hpet.c +++ b/arch/x86/kernel/hpet.c @@ -385,6 +385,7 @@ static int hpet_next_event(unsigned long cnt += (u32) delta; hpet_writel(cnt, HPET_Tn_CMP(timer)); + hpet_readl(HPET_Tn_CMP(timer)); /* pre-read for bnc#433746 */ /* * We need to read back the CMP register on certain HPET * implementations (ATI chipsets) which seem to delay the