diff options
Diffstat (limited to 'drivers/pci/pci.c')
| -rw-r--r-- | drivers/pci/pci.c | 91 |
1 files changed, 86 insertions, 5 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index cab05f31223f..460d046ab6fe 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -10,6 +10,8 @@ #include <linux/kernel.h> #include <linux/delay.h> #include <linux/init.h> +#include <linux/of.h> +#include <linux/of_pci.h> #include <linux/pci.h> #include <linux/pm.h> #include <linux/slab.h> @@ -3197,7 +3199,7 @@ static int pci_pm_reset(struct pci_dev *dev, int probe) { u16 csr; - if (!dev->pm_cap) + if (!dev->pm_cap || dev->dev_flags & PCI_DEV_FLAGS_NO_PM_RESET) return -ENOTTY; pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &csr); @@ -3271,7 +3273,8 @@ static int pci_parent_bus_reset(struct pci_dev *dev, int probe) { struct pci_dev *pdev; - if (pci_is_root_bus(dev->bus) || dev->subordinate || !dev->bus->self) + if (pci_is_root_bus(dev->bus) || dev->subordinate || + !dev->bus->self || dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET) return -ENOTTY; list_for_each_entry(pdev, &dev->bus->devices, bus_list) @@ -3305,7 +3308,8 @@ static int pci_dev_reset_slot_function(struct pci_dev *dev, int probe) { struct pci_dev *pdev; - if (dev->subordinate || !dev->slot) + if (dev->subordinate || !dev->slot || + dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET) return -ENOTTY; list_for_each_entry(pdev, &dev->bus->devices, bus_list) @@ -3557,6 +3561,20 @@ int pci_try_reset_function(struct pci_dev *dev) } EXPORT_SYMBOL_GPL(pci_try_reset_function); +/* Do any devices on or below this bus prevent a bus reset? */ +static bool pci_bus_resetable(struct pci_bus *bus) +{ + struct pci_dev *dev; + + list_for_each_entry(dev, &bus->devices, bus_list) { + if (dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET || + (dev->subordinate && !pci_bus_resetable(dev->subordinate))) + return false; + } + + return true; +} + /* Lock devices from the top of the tree down */ static void pci_bus_lock(struct pci_bus *bus) { @@ -3607,6 +3625,22 @@ unlock: return 0; } +/* Do any devices on or below this slot prevent a bus reset? */ +static bool pci_slot_resetable(struct pci_slot *slot) +{ + struct pci_dev *dev; + + list_for_each_entry(dev, &slot->bus->devices, bus_list) { + if (!dev->slot || dev->slot != slot) + continue; + if (dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET || + (dev->subordinate && !pci_bus_resetable(dev->subordinate))) + return false; + } + + return true; +} + /* Lock devices from the top of the tree down */ static void pci_slot_lock(struct pci_slot *slot) { @@ -3728,7 +3762,7 @@ static int pci_slot_reset(struct pci_slot *slot, int probe) { int rc; - if (!slot) + if (!slot || !pci_slot_resetable(slot)) return -ENOTTY; if (!probe) @@ -3820,7 +3854,7 @@ EXPORT_SYMBOL_GPL(pci_try_reset_slot); static int pci_bus_reset(struct pci_bus *bus, int probe) { - if (!bus->self) + if (!bus->self || !pci_bus_resetable(bus)) return -ENOTTY; if (probe) @@ -4439,6 +4473,53 @@ int pci_get_new_domain_nr(void) { return atomic_inc_return(&__domain_nr); } + +#ifdef CONFIG_PCI_DOMAINS_GENERIC +void pci_bus_assign_domain_nr(struct pci_bus *bus, struct device *parent) +{ + static int use_dt_domains = -1; + int domain = of_get_pci_domain_nr(parent->of_node); + + /* + * Check DT domain and use_dt_domains values. + * + * If DT domain property is valid (domain >= 0) and + * use_dt_domains != 0, the DT assignment is valid since this means + * we have not previously allocated a domain number by using + * pci_get_new_domain_nr(); we should also update use_dt_domains to + * 1, to indicate that we have just assigned a domain number from + * DT. + * + * If DT domain property value is not valid (ie domain < 0), and we + * have not previously assigned a domain number from DT + * (use_dt_domains != 1) we should assign a domain number by + * using the: + * + * pci_get_new_domain_nr() + * + * API and update the use_dt_domains value to keep track of method we + * are using to assign domain numbers (use_dt_domains = 0). + * + * All other combinations imply we have a platform that is trying + * to mix domain numbers obtained from DT and pci_get_new_domain_nr(), + * which is a recipe for domain mishandling and it is prevented by + * invalidating the domain value (domain = -1) and printing a + * corresponding error. + */ + if (domain >= 0 && use_dt_domains) { + use_dt_domains = 1; + } else if (domain < 0 && use_dt_domains != 1) { + use_dt_domains = 0; + domain = pci_get_new_domain_nr(); + } else { + dev_err(parent, "Node %s has inconsistent \"linux,pci-domain\" property in DT\n", + parent->of_node->full_name); + domain = -1; + } + + bus->domain_nr = domain; +} +#endif #endif /** |