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authorDavid S. Miller <davem@davemloft.net>2010-04-11 14:53:53 -0700
committerDavid S. Miller <davem@davemloft.net>2010-04-11 14:53:53 -0700
commit871039f02f8ec4ab2e5e9010718caa8e085786f1 (patch)
treef0d2b3127fc48c862967d68c46c2d46668137515 /arch/x86/kernel/hpet.c
parente4077e018b5ead3de9951fc01d8bf12eeeeeefed (diff)
parent4a1032faac94ebbf647460ae3e06fc21146eb280 (diff)
downloadop-kernel-dev-871039f02f8ec4ab2e5e9010718caa8e085786f1.zip
op-kernel-dev-871039f02f8ec4ab2e5e9010718caa8e085786f1.tar.gz
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts: drivers/net/stmmac/stmmac_main.c drivers/net/wireless/wl12xx/wl1271_cmd.c drivers/net/wireless/wl12xx/wl1271_main.c drivers/net/wireless/wl12xx/wl1271_spi.c net/core/ethtool.c net/mac80211/scan.c
Diffstat (limited to 'arch/x86/kernel/hpet.c')
-rw-r--r--arch/x86/kernel/hpet.c10
1 files changed, 9 insertions, 1 deletions
diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c
index ee4fa1b..23b4ecd 100644
--- a/arch/x86/kernel/hpet.c
+++ b/arch/x86/kernel/hpet.c
@@ -4,6 +4,7 @@
#include <linux/sysdev.h>
#include <linux/delay.h>
#include <linux/errno.h>
+#include <linux/slab.h>
#include <linux/hpet.h>
#include <linux/init.h>
#include <linux/cpu.h>
@@ -399,9 +400,15 @@ static int hpet_next_event(unsigned long delta,
* then we might have a real hardware problem. We can not do
* much about it here, but at least alert the user/admin with
* a prominent warning.
+ * An erratum on some chipsets (ICH9,..), results in comparator read
+ * immediately following a write returning old value. Workaround
+ * for this is to read this value second time, when first
+ * read returns old value.
*/
- WARN_ONCE(hpet_readl(HPET_Tn_CMP(timer)) != cnt,
+ if (unlikely((u32)hpet_readl(HPET_Tn_CMP(timer)) != cnt)) {
+ WARN_ONCE(hpet_readl(HPET_Tn_CMP(timer)) != cnt,
KERN_WARNING "hpet: compare register read back failed.\n");
+ }
return (s32)(hpet_readl(HPET_COUNTER) - cnt) >= 0 ? -ETIME : 0;
}
@@ -1143,6 +1150,7 @@ int hpet_set_periodic_freq(unsigned long freq)
do_div(clc, freq);
clc >>= hpet_clockevent.shift;
hpet_pie_delta = clc;
+ hpet_pie_limit = 0;
}
return 1;
}
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