powerpc/powernv: Improve kexec reliability
We add a machine_shutdown hook that frees the OPAL interrupts
(so they get masked at the source and don't fire while kexec'ing)
and which triggers an IODA reset on all the PCIe host bridges
which will have the effect of blocking all DMAs and subsequent
PCIs interrupts.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index 1da578b..3937aaa 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -1048,6 +1048,12 @@
return phb->ioda.pe_rmap[(bus->number << 8) | devfn];
}
+static void pnv_pci_ioda_shutdown(struct pnv_phb *phb)
+{
+ opal_pci_reset(phb->opal_id, OPAL_PCI_IODA_TABLE_RESET,
+ OPAL_ASSERT_RESET);
+}
+
void __init pnv_pci_init_ioda_phb(struct device_node *np, int ioda_type)
{
struct pci_controller *hose;
@@ -1178,6 +1184,9 @@
/* Setup TCEs */
phb->dma_dev_setup = pnv_pci_ioda_dma_dev_setup;
+ /* Setup shutdown function for kexec */
+ phb->shutdown = pnv_pci_ioda_shutdown;
+
/* Setup MSI support */
pnv_pci_init_ioda_msis(phb);