Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752635AbbGIK7D (ORCPT ); Thu, 9 Jul 2015 06:59:03 -0400 Received: from foss.arm.com ([217.140.101.70]:45485 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751261AbbGIK6x (ORCPT ); Thu, 9 Jul 2015 06:58:53 -0400 From: Lorenzo Pieralisi To: linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org Cc: Lorenzo Pieralisi , Ralf Baechle , "James E.J. Bottomley" , Michael Ellerman , Bjorn Helgaas , Richard Henderson , Benjamin Herrenschmidt , David Howells , Russell King , Tony Luck , "David S. Miller" , Ingo Molnar , Guenter Roeck , Michal Simek , Chris Zankel , Arnd Bergmann , Krzysztof Halasa , Phil Edworthy , Jason Gunthorpe , Jingoo Han , Lucas Stach , Simon Horman , Minghuan Lian , Murali Karicheri , Tanmay Inamdar , Kishon Vijay Abraham I , Thierry Reding , Thomas Petazzoni , Will Deacon , Jayachandran C , Suravee Suthikulpanit Subject: [RFT PATCH v3] PCI: move pci_read_bridge_bases to the generic PCI layer Date: Thu, 9 Jul 2015 11:59:16 +0100 Message-Id: <1436439557-21075-1-git-send-email-lorenzo.pieralisi@arm.com> X-Mailer: git-send-email 2.2.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8624 Lines: 264 When a PCI bus is scanned, upon PCI bridge detection the kernel has to read the bridge registers to set-up its resources so that the PCI resource hierarchy can be validated properly. Most if not all architectures read PCI bridge registers in the pcibios_fixup_bus hook, that is called by the PCI generic layer whenever a PCI bus is scanned. Since pci_read_bridge_bases is an arch agnostic operation (and it is carried out on all architectures) it can be moved to the generic PCI layer in order to consolidate code and remove the respective calls from the architectures back-ends. The PCI_PROBE_ONLY flag is not checked before calling pci_read_bridge_buses in the generic layer since reading the bridge bases is not related to resources assignment; this implies that it can be carried out safely on PCI_PROBE_ONLY systems too and should not affect architectures (alpha, mips) that check the PCI_PROBE_ONLY flag before reading the bridge bases. Signed-off-by: Lorenzo Pieralisi Cc: Ralf Baechle Cc: James E.J. Bottomley Cc: Michael Ellerman Cc: Bjorn Helgaas Cc: Richard Henderson Cc: Benjamin Herrenschmidt Cc: David Howells Cc: Russell King Cc: Tony Luck Cc: David S. Miller Cc: Ingo Molnar Cc: Guenter Roeck Cc: Michal Simek Cc: Chris Zankel --- v2->v3: - Dropped RFC status - Removed bridge resources claiming from pci_read_bridge_bases() v2: https://lkml.org/lkml/2015/6/9/187 v1->v2: - Moved pci_read_bridge_bases call to pci_scan_bridge to read bases before scanning devices - Added bridge resources claiming v1: https://lkml.org/lkml/2015/5/21/359 arch/alpha/kernel/pci.c | 7 +------ arch/frv/mb93090-mb00/pci-vdk.c | 2 -- arch/ia64/pci/pci.c | 1 - arch/microblaze/pci/pci-common.c | 9 +-------- arch/mips/pci/pci.c | 6 ------ arch/mn10300/unit-asb2305/pci.c | 1 - arch/powerpc/kernel/pci-common.c | 8 +------- arch/x86/pci/common.c | 1 - arch/xtensa/kernel/pci.c | 4 ---- drivers/parisc/dino.c | 3 --- drivers/parisc/lba_pci.c | 1 - drivers/pci/probe.c | 9 +++++++++ 12 files changed, 12 insertions(+), 40 deletions(-) diff --git a/arch/alpha/kernel/pci.c b/arch/alpha/kernel/pci.c index 82f738e..cded02c 100644 --- a/arch/alpha/kernel/pci.c +++ b/arch/alpha/kernel/pci.c @@ -242,12 +242,7 @@ pci_restore_srm_config(void) void pcibios_fixup_bus(struct pci_bus *bus) { - struct pci_dev *dev = bus->self; - - if (pci_has_flag(PCI_PROBE_ONLY) && dev && - (dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) { - pci_read_bridge_bases(bus); - } + struct pci_dev *dev; list_for_each_entry(dev, &bus->devices, bus_list) { pdev_save_srm_config(dev); diff --git a/arch/frv/mb93090-mb00/pci-vdk.c b/arch/frv/mb93090-mb00/pci-vdk.c index f211839..f9c86c4 100644 --- a/arch/frv/mb93090-mb00/pci-vdk.c +++ b/arch/frv/mb93090-mb00/pci-vdk.c @@ -294,8 +294,6 @@ void pcibios_fixup_bus(struct pci_bus *bus) printk("### PCIBIOS_FIXUP_BUS(%d)\n",bus->number); #endif - pci_read_bridge_bases(bus); - if (bus->number == 0) { struct pci_dev *dev; list_for_each_entry(dev, &bus->devices, bus_list) { diff --git a/arch/ia64/pci/pci.c b/arch/ia64/pci/pci.c index 7cc3be9..563228b 100644 --- a/arch/ia64/pci/pci.c +++ b/arch/ia64/pci/pci.c @@ -534,7 +534,6 @@ void pcibios_fixup_bus(struct pci_bus *b) struct pci_dev *dev; if (b->self) { - pci_read_bridge_bases(b); pcibios_fixup_bridge_resources(b->self); } list_for_each_entry(dev, &b->devices, bus_list) diff --git a/arch/microblaze/pci/pci-common.c b/arch/microblaze/pci/pci-common.c index ae838ed..6b8b752 100644 --- a/arch/microblaze/pci/pci-common.c +++ b/arch/microblaze/pci/pci-common.c @@ -863,14 +863,7 @@ void pcibios_setup_bus_devices(struct pci_bus *bus) void pcibios_fixup_bus(struct pci_bus *bus) { - /* When called from the generic PCI probe, read PCI<->PCI bridge - * bases. This is -not- called when generating the PCI tree from - * the OF device-tree. - */ - if (bus->self != NULL) - pci_read_bridge_bases(bus); - - /* Now fixup the bus bus */ + /* Fixup the bus */ pcibios_setup_bus_self(bus); /* Now fixup devices on that bus */ diff --git a/arch/mips/pci/pci.c b/arch/mips/pci/pci.c index b8a0bf5..c6996cf 100644 --- a/arch/mips/pci/pci.c +++ b/arch/mips/pci/pci.c @@ -311,12 +311,6 @@ int pcibios_enable_device(struct pci_dev *dev, int mask) void pcibios_fixup_bus(struct pci_bus *bus) { - struct pci_dev *dev = bus->self; - - if (pci_has_flag(PCI_PROBE_ONLY) && dev && - (dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) { - pci_read_bridge_bases(bus); - } } EXPORT_SYMBOL(PCIBIOS_MIN_IO); diff --git a/arch/mn10300/unit-asb2305/pci.c b/arch/mn10300/unit-asb2305/pci.c index 3dfe2d3..deaa893 100644 --- a/arch/mn10300/unit-asb2305/pci.c +++ b/arch/mn10300/unit-asb2305/pci.c @@ -324,7 +324,6 @@ void pcibios_fixup_bus(struct pci_bus *bus) struct pci_dev *dev; if (bus->self) { - pci_read_bridge_bases(bus); pcibios_fixup_bridge_resources(bus->self); } diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c index b9de34d..02c1d5d 100644 --- a/arch/powerpc/kernel/pci-common.c +++ b/arch/powerpc/kernel/pci-common.c @@ -1044,13 +1044,7 @@ void pcibios_set_master(struct pci_dev *dev) void pcibios_fixup_bus(struct pci_bus *bus) { - /* When called from the generic PCI probe, read PCI<->PCI bridge - * bases. This is -not- called when generating the PCI tree from - * the OF device-tree. - */ - pci_read_bridge_bases(bus); - - /* Now fixup the bus bus */ + /* Fixup the bus */ pcibios_setup_bus_self(bus); /* Now fixup devices on that bus */ diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c index 8fd6f44..3bff244 100644 --- a/arch/x86/pci/common.c +++ b/arch/x86/pci/common.c @@ -166,7 +166,6 @@ void pcibios_fixup_bus(struct pci_bus *b) { struct pci_dev *dev; - pci_read_bridge_bases(b); list_for_each_entry(dev, &b->devices, bus_list) pcibios_fixup_device_resources(dev); } diff --git a/arch/xtensa/kernel/pci.c b/arch/xtensa/kernel/pci.c index b848cc3..d27b4dc 100644 --- a/arch/xtensa/kernel/pci.c +++ b/arch/xtensa/kernel/pci.c @@ -210,10 +210,6 @@ subsys_initcall(pcibios_init); void pcibios_fixup_bus(struct pci_bus *bus) { - if (bus->parent) { - /* This is a subordinate bridge */ - pci_read_bridge_bases(bus); - } } void pcibios_set_master(struct pci_dev *dev) diff --git a/drivers/parisc/dino.c b/drivers/parisc/dino.c index a0580af..baec33c 100644 --- a/drivers/parisc/dino.c +++ b/drivers/parisc/dino.c @@ -560,9 +560,6 @@ dino_fixup_bus(struct pci_bus *bus) } else if (bus->parent) { int i; - pci_read_bridge_bases(bus); - - for(i = PCI_BRIDGE_RESOURCES; i < PCI_NUM_RESOURCES; i++) { if((bus->self->resource[i].flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0) diff --git a/drivers/parisc/lba_pci.c b/drivers/parisc/lba_pci.c index dceb9dd..901e1a3 100644 --- a/drivers/parisc/lba_pci.c +++ b/drivers/parisc/lba_pci.c @@ -693,7 +693,6 @@ lba_fixup_bus(struct pci_bus *bus) if (bus->parent) { int i; /* PCI-PCI Bridge */ - pci_read_bridge_bases(bus); for (i = PCI_BRIDGE_RESOURCES; i < PCI_NUM_RESOURCES; i++) pci_claim_bridge_resource(bus->self, i); } else { diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index c80626f..de1c424 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -842,6 +842,11 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass) child->bridge_ctl = bctl; } + /* + * Read and initialize bridge resources. + */ + pci_read_bridge_bases(child); + cmax = pci_scan_child_bus(child); if (cmax > subordinate) dev_warn(&dev->dev, "bridge has subordinate %02x but max busn %02x\n", @@ -902,6 +907,10 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass) if (!is_cardbus) { child->bridge_ctl = bctl; + /* + * Read and initialize bridge resources. + */ + pci_read_bridge_bases(child); max = pci_scan_child_bus(child); } else { /* -- 2.2.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/