powerpc/pseries: Disable MSI using new interface if possible

On upcoming hardware, we have a PCI adapter with two functions, one of
which uses MSI and the other uses MSI-X. This adapter, when MSI is
disabled using the "old" firmware interface (RTAS_CHANGE_FN), still
signals an MSI-X interrupt and triggers an EEH. We are working with the
vendor to ensure that the hardware is not at fault, but if we use the
"new" interface (RTAS_CHANGE_MSI_FN) to disable MSI, we also
automatically disable MSI-X and the adapter does not appear to signal
any stray MSI-X interrupt.

Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Acked-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Nishanth Aravamudan 2011-03-03 15:41:02 +00:00 committed by Benjamin Herrenschmidt
parent 17b9f9e265
commit 964a29962c
1 changed files with 12 additions and 2 deletions

View File

@ -93,8 +93,18 @@ static void rtas_disable_msi(struct pci_dev *pdev)
if (!pdn)
return;
if (rtas_change_msi(pdn, RTAS_CHANGE_FN, 0) != 0)
pr_debug("rtas_msi: Setting MSIs to 0 failed!\n");
/*
* disabling MSI with the explicit interface also disables MSI-X
*/
if (rtas_change_msi(pdn, RTAS_CHANGE_MSI_FN, 0) != 0) {
/*
* may have failed because explicit interface is not
* present
*/
if (rtas_change_msi(pdn, RTAS_CHANGE_FN, 0) != 0) {
pr_debug("rtas_msi: Setting MSIs to 0 failed!\n");
}
}
}
static int rtas_query_irq_number(struct pci_dn *pdn, int offset)