diff options
author | Gavin Shan <gwshan@linux.vnet.ibm.com> | 2015-03-17 05:15:02 (GMT) |
---|---|---|
committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2015-03-24 02:15:49 (GMT) |
commit | cca87d303c85b257a7b0fd34f9d6fce1c59880a2 (patch) | |
tree | 4145eab3e328314e60b9dcc3590616a93aa7bb90 /arch/powerpc/kernel | |
parent | 12a89dbac7914c58b0d207ef608e1c02534708bc (diff) | |
download | linux-cca87d303c85b257a7b0fd34f9d6fce1c59880a2.tar.xz |
powerpc/pci: Refactor pci_dn
Currently, the PCI config accessors are implemented based on device node.
Unfortunately, SRIOV VFs won't have the corresponding device nodes. pci_dn
will be used in replacement with device node for SRIOV VFs. So we have to
use pci_dn in PCI config accessors.
The patch refactors pci_dn in following aspects to make it ready to be used
in PCI config accessors as we do in subsequent patch:
* pci_dn is organized as a hierarchy tree. PCI device's pci_dn is
put to the child list of pci_dn of its upstream bridge or PHB. VF's
pci_dn will be put to the child list of pci_dn of PF's bridge.
* For one particular PCI device (VF or not), its pci_dn can be
found from pdev->dev.archdata.pci_data, PCI_DN(devnode), or
parent's list. The fast path (fetching pci_dn through PCI device
instance) is populated during early fixup time.
[bhelgaas: changelog]
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/kernel')
-rw-r--r-- | arch/powerpc/kernel/pci_dn.c | 130 |
1 files changed, 126 insertions, 4 deletions
diff --git a/arch/powerpc/kernel/pci_dn.c b/arch/powerpc/kernel/pci_dn.c index 83df307..0ab2dad 100644 --- a/arch/powerpc/kernel/pci_dn.c +++ b/arch/powerpc/kernel/pci_dn.c @@ -32,12 +32,108 @@ #include <asm/ppc-pci.h> #include <asm/firmware.h> +/* + * The function is used to find the firmware data of one + * specific PCI device, which is attached to the indicated + * PCI bus. For VFs, their firmware data is linked to that + * one of PF's bridge. For other devices, their firmware + * data is linked to that of their bridge. + */ +static struct pci_dn *pci_bus_to_pdn(struct pci_bus *bus) +{ + struct pci_bus *pbus; + struct device_node *dn; + struct pci_dn *pdn; + + /* + * We probably have virtual bus which doesn't + * have associated bridge. + */ + pbus = bus; + while (pbus) { + if (pci_is_root_bus(pbus) || pbus->self) + break; + + pbus = pbus->parent; + } + + /* + * Except virtual bus, all PCI buses should + * have device nodes. + */ + dn = pci_bus_to_OF_node(pbus); + pdn = dn ? PCI_DN(dn) : NULL; + + return pdn; +} + +struct pci_dn *pci_get_pdn_by_devfn(struct pci_bus *bus, + int devfn) +{ + struct device_node *dn = NULL; + struct pci_dn *parent, *pdn; + struct pci_dev *pdev = NULL; + + /* Fast path: fetch from PCI device */ + list_for_each_entry(pdev, &bus->devices, bus_list) { + if (pdev->devfn == devfn) { + if (pdev->dev.archdata.pci_data) + return pdev->dev.archdata.pci_data; + + dn = pci_device_to_OF_node(pdev); + break; + } + } + + /* Fast path: fetch from device node */ + pdn = dn ? PCI_DN(dn) : NULL; + if (pdn) + return pdn; + + /* Slow path: fetch from firmware data hierarchy */ + parent = pci_bus_to_pdn(bus); + if (!parent) + return NULL; + + list_for_each_entry(pdn, &parent->child_list, list) { + if (pdn->busno == bus->number && + pdn->devfn == devfn) + return pdn; + } + + return NULL; +} + struct pci_dn *pci_get_pdn(struct pci_dev *pdev) { - struct device_node *dn = pci_device_to_OF_node(pdev); - if (!dn) + struct device_node *dn; + struct pci_dn *parent, *pdn; + + /* Search device directly */ + if (pdev->dev.archdata.pci_data) + return pdev->dev.archdata.pci_data; + + /* Check device node */ + dn = pci_device_to_OF_node(pdev); + pdn = dn ? PCI_DN(dn) : NULL; + if (pdn) + return pdn; + + /* + * VFs don't have device nodes. We hook their + * firmware data to PF's bridge. + */ + parent = pci_bus_to_pdn(pdev->bus); + if (!parent) return NULL; - return PCI_DN(dn); + + list_for_each_entry(pdn, &parent->child_list, list) { + if (pdn->busno == pdev->bus->number && + pdn->devfn == pdev->devfn) + return pdn; + } + + return NULL; } /* @@ -49,6 +145,7 @@ void *update_dn_pci_info(struct device_node *dn, void *data) struct pci_controller *phb = data; const __be32 *type = of_get_property(dn, "ibm,pci-config-space-type", NULL); const __be32 *regs; + struct device_node *parent; struct pci_dn *pdn; pdn = zalloc_maybe_bootmem(sizeof(*pdn), GFP_KERNEL); @@ -70,6 +167,15 @@ void *update_dn_pci_info(struct device_node *dn, void *data) } pdn->pci_ext_config_space = (type && of_read_number(type, 1) == 1); + + /* Attach to parent node */ + INIT_LIST_HEAD(&pdn->child_list); + INIT_LIST_HEAD(&pdn->list); + parent = of_get_parent(dn); + pdn->parent = parent ? PCI_DN(parent) : NULL; + if (pdn->parent) + list_add_tail(&pdn->list, &pdn->parent->child_list); + return NULL; } @@ -147,8 +253,11 @@ void pci_devs_phb_init_dynamic(struct pci_controller *phb) /* PHB nodes themselves must not match */ update_dn_pci_info(dn, phb); pdn = dn->data; - if (pdn) + if (pdn) { pdn->devfn = pdn->busno = -1; + pdn->phb = phb; + phb->pci_data = pdn; + } /* Update dn->phb ptrs for new phb and children devices */ traverse_pci_devices(dn, update_dn_pci_info, phb); @@ -171,3 +280,16 @@ void __init pci_devs_phb_init(void) list_for_each_entry_safe(phb, tmp, &hose_list, list_node) pci_devs_phb_init_dynamic(phb); } + +static void pci_dev_pdn_setup(struct pci_dev *pdev) +{ + struct pci_dn *pdn; + + if (pdev->dev.archdata.pci_data) + return; + + /* Setup the fast path */ + pdn = pci_get_pdn(pdev); + pdev->dev.archdata.pci_data = pdn; +} +DECLARE_PCI_FIXUP_EARLY(PCI_ANY_ID, PCI_ANY_ID, pci_dev_pdn_setup); |