[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Xen-devel] [PATCH] x86/HPET: don't disable interrupt delivery right after setting it up


  • To: "xen-devel" <xen-devel@xxxxxxxxxxxxx>
  • From: "Jan Beulich" <JBeulich@xxxxxxxx>
  • Date: Thu, 27 Sep 2012 15:40:01 +0100
  • Delivery-date: Thu, 27 Sep 2012 14:40:09 +0000
  • List-id: Xen developer discussion <xen-devel.lists.xen.org>

We shouldn't clear HPET_TN_FSB right after we (indirectly, via
request_irq()) enabled it for the channels we intend to use for
broadcasts.

This fixes a regression introduced by c/s 25103:0b0e42dc4f0a.

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
---
This fixes the MWAIT idle driver problem on the box that I was able to
(artificially) reproduce it with. Hence I subsequently intend to revert
25960:6bf8b882df8f, but I'm not intending to do this before getting a
push there.

I'm surprised that this didn't hit anyone so far with the ACPI-based
idle driver...

--- 2012-09-21.orig/xen/arch/x86/hpet.c 2012-09-27 16:10:35.000000000 +0200
+++ 2012-09-21/xen/arch/x86/hpet.c      2012-09-27 16:10:07.000000000 +0200
@@ -533,7 +533,7 @@ void __init hpet_broadcast_init(void)
     {
         /* set HPET Tn as oneshot */
         cfg = hpet_read32(HPET_Tn_CFG(hpet_events[i].idx));
-        cfg &= ~(HPET_TN_LEVEL | HPET_TN_PERIODIC | HPET_TN_FSB);
+        cfg &= ~(HPET_TN_LEVEL | HPET_TN_PERIODIC);
         cfg |= HPET_TN_ENABLE | HPET_TN_32BIT;
         hpet_write32(cfg, HPET_Tn_CFG(hpet_events[i].idx));
 
@@ -590,7 +590,7 @@ void hpet_broadcast_resume(void)
 
         /* set HPET Tn as oneshot */
         cfg = hpet_read32(HPET_Tn_CFG(hpet_events[i].idx));
-        cfg &= ~(HPET_TN_LEVEL | HPET_TN_PERIODIC | HPET_TN_FSB);
+        cfg &= ~(HPET_TN_LEVEL | HPET_TN_PERIODIC);
         cfg |= HPET_TN_ENABLE | HPET_TN_32BIT;
         hpet_write32(cfg, HPET_Tn_CFG(hpet_events[i].idx));
 



Attachment: x86-HPET-interrupts.patch
Description: Text document

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel

 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.