From fbce44d0ed42e4653172376f4dfeaa5710f06a27 Mon Sep 17 00:00:00 2001 From: Gavin Shan Date: Fri, 24 Jun 2016 16:44:19 +1000 Subject: powerpc/powernv: Call opal_pci_poll() if needed When issuing PHB reset, OPAL API opal_pci_poll() is called to drive the state machine in OPAL forward. However, we needn't always call the function under some circumstances like reset deassert. This avoids calling opal_pci_poll() when OPAL_SUCCESS is returned from opal_pci_reset(). Except the overhead introduced by additional one unnecessary OPAL call, I didn't run into real issue because of this. Reported-by: Pridhiviraj Paidipeddi Signed-off-by: Gavin Shan Signed-off-by: Michael Ellerman --- arch/powerpc/platforms/powernv/eeh-powernv.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'arch/powerpc/platforms/powernv/eeh-powernv.c') diff --git a/arch/powerpc/platforms/powernv/eeh-powernv.c b/arch/powerpc/platforms/powernv/eeh-powernv.c index 68f1a854f97d..995947d81989 100644 --- a/arch/powerpc/platforms/powernv/eeh-powernv.c +++ b/arch/powerpc/platforms/powernv/eeh-powernv.c @@ -763,7 +763,8 @@ int pnv_eeh_phb_reset(struct pci_controller *hose, int option) * reset followed by hot reset on root bus. So we also * need the PCI bus settlement delay. */ - rc = pnv_eeh_poll(phb->opal_id); + if (rc > 0) + rc = pnv_eeh_poll(phb->opal_id); if (option == EEH_RESET_DEACTIVATE) { if (system_state < SYSTEM_RUNNING) udelay(1000 * EEH_PE_RST_SETTLE_TIME); @@ -806,7 +807,8 @@ static int pnv_eeh_root_reset(struct pci_controller *hose, int option) goto out; /* Poll state of the PHB until the request is done */ - rc = pnv_eeh_poll(phb->opal_id); + if (rc > 0) + rc = pnv_eeh_poll(phb->opal_id); if (option == EEH_RESET_DEACTIVATE) msleep(EEH_PE_RST_SETTLE_TIME); out: -- cgit v1.2.3