On Sat, Feb 25, 2006 at 10:41:12PM -0800, Randy.Dunlap wrote:
> OK, updated patch for "pci=nomsi" is now at
> http://www.xenotime.net/linux/patches/pci_nomsi.patch
After sleeping on it, I realised this wouldn't work if CONFIG_PCI_MSI
is disabled. So how about this (not even compile-tested):
Signed-off-by: Matthew Wilcox <[email protected]>
Index: ./Documentation/kernel-parameters.txt
===================================================================
RCS file: /var/cvs/linux-2.6/Documentation/kernel-parameters.txt,v
retrieving revision 1.41.4.1
diff -u -p -r1.41.4.1 kernel-parameters.txt
--- ./Documentation/kernel-parameters.txt 18 Feb 2006 05:26:01 -0000 1.41.4.1
+++ ./Documentation/kernel-parameters.txt 26 Feb 2006 15:58:40 -0000
@@ -49,6 +49,7 @@ restrictions referred to are that the re
MCA MCA bus support is enabled.
MDA MDA console support is enabled.
MOUSE Appropriate mouse support is enabled.
+ MSI Message Signaled Interrupts (PCI).
MTD MTD support is enabled.
NET Appropriate network support is enabled.
NUMA NUMA support is enabled.
@@ -1135,6 +1136,9 @@ running once the system is up.
Mechanism 2.
nommconf [IA-32,X86_64] Disable use of MMCONFIG for PCI
Configuration
+ nomsi [MSI] If the PCI_MSI kernel config parameter is
+ enabled, this kernel boot option can be used to
+ disable the use of MSI interrupts system-wide.
nosort [IA-32] Don't sort PCI devices according to
order given by the PCI BIOS. This sorting is
done to get a device order compatible with
Index: ./drivers/pci/Kconfig
===================================================================
RCS file: /var/cvs/linux-2.6/drivers/pci/Kconfig,v
retrieving revision 1.8
diff -u -p -r1.8 Kconfig
--- ./drivers/pci/Kconfig 14 Sep 2005 12:56:32 -0000 1.8
+++ ./drivers/pci/Kconfig 26 Feb 2006 15:58:40 -0000
@@ -11,6 +11,10 @@ config PCI_MSI
generate an interrupt using an inbound Memory Write on its
PCI bus instead of asserting a device IRQ pin.
+ Use of PCI MSI interrupts can be disabled at kernel boot time
+ by using the 'pci=nomsi' option. This disables MSI for the
+ entire system.
+
If you don't know what to do here, say N.
config PCI_LEGACY_PROC
Index: ./drivers/pci/msi.c
===================================================================
RCS file: /var/cvs/linux-2.6/drivers/pci/msi.c,v
retrieving revision 1.17
diff -u -p -r1.17 msi.c
--- ./drivers/pci/msi.c 4 Feb 2006 04:51:55 -0000 1.17
+++ ./drivers/pci/msi.c 26 Feb 2006 15:58:40 -0000
@@ -755,6 +755,9 @@ void pci_disable_msi(struct pci_dev* dev
u16 control;
unsigned long flags;
+ if (!pci_msi_enable)
+ return;
+
if (!dev || !(pos = pci_find_capability(dev, PCI_CAP_ID_MSI)))
return;
@@ -1006,6 +1009,9 @@ void pci_disable_msix(struct pci_dev* de
int pos, temp;
u16 control;
+ if (!pci_msi_enable)
+ return;
+
if (!dev || !(pos = pci_find_capability(dev, PCI_CAP_ID_MSIX)))
return;
@@ -1121,6 +1127,11 @@ void msi_remove_pci_irq_vectors(struct p
}
dev->irq = temp; /* Restore IOAPIC IRQ */
}
+}
+
+void pci_no_msi(void)
+{
+ pci_msi_enable = 0;
}
EXPORT_SYMBOL(pci_enable_msi);
Index: ./drivers/pci/pci.c
===================================================================
RCS file: /var/cvs/linux-2.6/drivers/pci/pci.c,v
retrieving revision 1.28
diff -u -p -r1.28 pci.c
--- ./drivers/pci/pci.c 4 Feb 2006 04:51:55 -0000 1.28
+++ ./drivers/pci/pci.c 26 Feb 2006 15:58:40 -0000
@@ -900,8 +900,12 @@ static int __devinit pci_setup(char *str
if (k)
*k++ = 0;
if (*str && (str = pcibios_setup(str)) && *str) {
- /* PCI layer options should be handled here */
- printk(KERN_ERR "PCI: Unknown option `%s'\n", str);
+ if (!strcmp(str, "nomsi")) {
+ pci_no_msi();
+ } else {
+ printk(KERN_ERR "PCI: Unknown option `%s'\n",
+ str);
+ }
}
str = k;
}
Index: ./drivers/pci/pci.h
===================================================================
RCS file: /var/cvs/linux-2.6/drivers/pci/pci.h,v
retrieving revision 1.13
diff -u -p -r1.13 pci.h
--- ./drivers/pci/pci.h 17 Jan 2006 14:51:41 -0000 1.13
+++ ./drivers/pci/pci.h 26 Feb 2006 15:58:40 -0000
@@ -50,8 +50,10 @@ extern int pci_msi_quirk;
#ifdef CONFIG_PCI_MSI
void disable_msi_mode(struct pci_dev *dev, int pos, int type);
+void pci_no_msi(void);
#else
static inline void disable_msi_mode(struct pci_dev *dev, int pos, int type) { }
+static inline void pci_no_msi(void) { }
#endif
extern int pcie_mch_quirk;
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
