diff options
-rw-r--r-- | drivers/platform/x86/p2sb.c | 42 |
1 files changed, 33 insertions, 9 deletions
diff --git a/drivers/platform/x86/p2sb.c b/drivers/platform/x86/p2sb.c index 46c108bbcbba..cbbb0f809704 100644 --- a/drivers/platform/x86/p2sb.c +++ b/drivers/platform/x86/p2sb.c @@ -101,10 +101,8 @@ static int p2sb_scan_and_cache(struct pci_bus *bus, unsigned int devfn) /* * The BIOS prevents the P2SB device from being enumerated by the PCI * subsystem, so we need to unhide and hide it back to lookup the BAR. - * Unhide the P2SB device here, if needed. */ - if (p2sb_hidden_by_bios) - pci_bus_write_config_dword(bus, devfn, P2SBC, 0); + pci_bus_write_config_dword(bus, devfn, P2SBC, 0); /* Scan the P2SB device and cache its BAR0 */ p2sb_scan_and_cache_devfn(bus, devfn); @@ -113,9 +111,7 @@ static int p2sb_scan_and_cache(struct pci_bus *bus, unsigned int devfn) if (devfn == P2SB_DEVFN_GOLDMONT) p2sb_scan_and_cache_devfn(bus, SPI_DEVFN_GOLDMONT); - /* Hide the P2SB device, if it was hidden */ - if (p2sb_hidden_by_bios) - pci_bus_write_config_dword(bus, devfn, P2SBC, P2SBC_HIDE); + pci_bus_write_config_dword(bus, devfn, P2SBC, P2SBC_HIDE); if (!p2sb_valid_resource(&p2sb_resources[PCI_FUNC(devfn)].res)) return -ENOENT; @@ -142,7 +138,7 @@ static int p2sb_cache_resources(void) u32 value = P2SBC_HIDE; struct pci_bus *bus; u16 class; - int ret; + int ret = 0; /* Get devfn for P2SB device itself */ p2sb_get_devfn(&devfn_p2sb); @@ -168,7 +164,12 @@ static int p2sb_cache_resources(void) pci_bus_read_config_dword(bus, devfn_p2sb, P2SBC, &value); p2sb_hidden_by_bios = value & P2SBC_HIDE; - ret = p2sb_scan_and_cache(bus, devfn_p2sb); + /* + * If the BIOS does not hide the P2SB device then its resources + * are accesilble. Cache them only if the P2SB device is hidden. + */ + if (p2sb_hidden_by_bios) + ret = p2sb_scan_and_cache(bus, devfn_p2sb); pci_unlock_rescan_remove(); @@ -191,6 +192,26 @@ static int p2sb_read_from_cache(struct pci_bus *bus, unsigned int devfn, return 0; } +static int p2sb_read_from_dev(struct pci_bus *bus, unsigned int devfn, + struct resource *mem) +{ + struct pci_dev *pdev; + int ret = 0; + + pdev = pci_get_slot(bus, devfn); + if (!pdev) + return -ENODEV; + + if (p2sb_valid_resource(pci_resource_n(pdev, 0))) + p2sb_read_bar0(pdev, mem); + else + ret = -ENOENT; + + pci_dev_put(pdev); + + return ret; +} + /** * p2sb_bar - Get Primary to Sideband (P2SB) bridge device BAR * @bus: PCI bus to communicate with @@ -214,7 +235,10 @@ int p2sb_bar(struct pci_bus *bus, unsigned int devfn, struct resource *mem) if (!devfn) p2sb_get_devfn(&devfn); - return p2sb_read_from_cache(bus, devfn, mem); + if (p2sb_hidden_by_bios) + return p2sb_read_from_cache(bus, devfn, mem); + + return p2sb_read_from_dev(bus, devfn, mem); } EXPORT_SYMBOL_GPL(p2sb_bar); |