From db1266c852611436daa01a89c272722ec39cf916 Mon Sep 17 00:00:00 2001 From: Gavin Shan Date: Mon, 20 Aug 2012 03:49:18 +0000 Subject: [PATCH] powerpc/powernv: Skip check on PE if necessary While the device driver or PCI core tries to enable PCI device, the platform dependent callback "ppc_md.pcibios_enable_device_hook" will be called to check if there has one associated PE for the PCI device. If we don't have the associated PE for the PCI device, it's not allowed to enable the PCI device. Unfortunately, there might have some cases we have to enable the PCI device (e.g. P2P bridge), but the PEs have not been created yet. The patch handles the unfortunate cases. Each PHB (struct pnv_phb) has one field "initialized" to trace if the PEs have been created and configured or not. When the PEs are not available, we won't check the associated PE for the PCI device to be enabled. Signed-off-by: Gavin Shan Reviewed-by: Ram Pai Reviewed-by: Richard Yang Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/platforms/powernv/pci-ioda.c | 19 ++++++++++++++++++- arch/powerpc/platforms/powernv/pci.h | 1 + 2 files changed, 19 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c index edf39e099945..c4461ad8a689 100644 --- a/arch/powerpc/platforms/powernv/pci-ioda.c +++ b/arch/powerpc/platforms/powernv/pci-ioda.c @@ -1244,9 +1244,14 @@ static void __devinit pnv_pci_ioda_setup_seg(void) static void __devinit pnv_pci_ioda_setup_DMA(void) { struct pci_controller *hose, *tmp; + struct pnv_phb *phb; list_for_each_entry_safe(hose, tmp, &hose_list, list_node) { pnv_ioda_setup_dma(hose->private_data); + + /* Mark the PHB initialization done */ + phb = hose->private_data; + phb->initialized = 1; } } @@ -1300,10 +1305,22 @@ static resource_size_t pnv_pci_window_alignment(struct pci_bus *bus, */ static int __devinit pnv_pci_enable_device_hook(struct pci_dev *dev) { - struct pci_dn *pdn = pnv_ioda_get_pdn(dev); + struct pci_controller *hose = pci_bus_to_host(dev->bus); + struct pnv_phb *phb = hose->private_data; + struct pci_dn *pdn; + /* The function is probably called while the PEs have + * not be created yet. For example, resource reassignment + * during PCI probe period. We just skip the check if + * PEs isn't ready. + */ + if (!phb->initialized) + return 0; + + pdn = pnv_ioda_get_pdn(dev); if (!pdn || pdn->pe_number == IODA_INVALID_PE) return -EINVAL; + return 0; } diff --git a/arch/powerpc/platforms/powernv/pci.h b/arch/powerpc/platforms/powernv/pci.h index b70720bd9430..7cfb7c883deb 100644 --- a/arch/powerpc/platforms/powernv/pci.h +++ b/arch/powerpc/platforms/powernv/pci.h @@ -69,6 +69,7 @@ struct pnv_phb { enum pnv_phb_model model; u64 opal_id; void __iomem *regs; + int initialized; spinlock_t lock; #ifdef CONFIG_PCI_MSI