[PATCH] msi: sanely support hardware level msi disabling

In some cases when we are not using msi we need a way to ensure that the
hardware does not have an msi capability enabled.  Currently the code has been
calling disable_msi_mode to try and achieve that.  However disable_msi_mode
has several other side effects and is only available when msi support is
compiled in so it isn't really appropriate.

Instead this patch implements pci_msi_off which disables all msi and msix
capabilities unconditionally with no additional side effects.

pci_disable_device was redundantly clearing the bus master enable flag and
clearing the msi enable bit.  A device that is not allowed to perform bus
mastering operations cannot generate intx or msi interrupt messages as those
are essentially a special case of dma, and require bus mastering.  So the call
in pci_disable_device to disable msi capabilities was redundant.

quirk_pcie_pxh also called disable_msi_mode and is updated to use pci_msi_off.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Eric W. Biederman
2007-03-05 00:30:07 -08:00
committed by Linus Torvalds
parent 58a53b246b
commit f5f2b13129
7 changed files with 35 additions and 16 deletions

View File

@@ -968,7 +968,6 @@ void pci_scan_msi_device(struct pci_dev *dev) {}
int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec) {return -1;}
void pci_disable_msix(struct pci_dev *dev) {}
void msi_remove_pci_irq_vectors(struct pci_dev *dev) {}
void disable_msi_mode(struct pci_dev *dev, int pos, int type) {}
void pci_no_msi(void) {}
EXPORT_SYMBOL(pci_enable_msix);
EXPORT_SYMBOL(pci_disable_msix);