Re: IO-APIC on nforce2 [PATCH] + [PATCH] for nmi_debug=1 + [PATCH]for idle=C1halt, 2.6.5

From: Jeff Garzik
Date: Tue May 04 2004 - 16:15:44 EST


Bartlomiej Zolnierkiewicz wrote:
+/*
+ * Fixup for C1 Halt Disconnect problem on nForce2 systems.
+ *
+ * From information provided by "Allen Martin" <AMartin@xxxxxxxxxx>:
+ *
+ * A hang is caused when the CPU generates a very fast CONNECT/HALT cycle
+ * sequence. Workaround is to set the SYSTEM_IDLE_TIMEOUT to 80 ns.
+ * This allows the state-machine and timer to return to a proper state within
+ * 80 ns of the CONNECT and probe appearing together. Since the CPU will not
+ * issue another HALT within 80 ns of the initial HALT, the failure condition
+ * is avoided.
+ */
+static void __devinit pci_fixup_nforce2(struct pci_dev *dev)


Minor nit: is __devinit really needed?

You're changing a northbridge or a southbridge, not a PCI card, I presume...? That would only need to be done once, when the kernel is booted, regardless of CONFIG_HOTPLUG AFAICS.

Jeff



-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/