6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Shin'ichiro Kawasaki <shinichiro.kawasaki@xxxxxxx> [ Upstream commit 0286070c74ee48391fc07f7f617460479472d221 ] To prepare for the following fix, move the code to hide and unhide the P2SB device from p2sb_cache_resources() to p2sb_scan_and_cache(). Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@xxxxxxx> Reviewed-by: Hans de Goede <hdegoede@xxxxxxxxxx> Link: https://lore.kernel.org/r/20241128002836.373745-4-shinichiro.kawasaki@xxxxxxx Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx> Stable-dep-of: 360c400d0f56 ("p2sb: Do not scan and remove the P2SB device when it is unhidden") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/platform/x86/p2sb.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-) diff --git a/drivers/platform/x86/p2sb.c b/drivers/platform/x86/p2sb.c index 273ac90c8fbd..0bc6b21c4c20 100644 --- a/drivers/platform/x86/p2sb.c +++ b/drivers/platform/x86/p2sb.c @@ -97,6 +97,14 @@ static void p2sb_scan_and_cache_devfn(struct pci_bus *bus, unsigned int devfn) 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); + /* Scan the P2SB device and cache its BAR0 */ p2sb_scan_and_cache_devfn(bus, devfn); @@ -104,6 +112,10 @@ 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); + if (!p2sb_valid_resource(&p2sb_resources[PCI_FUNC(devfn)].res)) return -ENOENT; @@ -152,22 +164,11 @@ static int p2sb_cache_resources(void) */ pci_lock_rescan_remove(); - /* - * 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. - */ pci_bus_read_config_dword(bus, devfn_p2sb, P2SBC, &value); p2sb_hidden_by_bios = value & P2SBC_HIDE; - if (p2sb_hidden_by_bios) - pci_bus_write_config_dword(bus, devfn_p2sb, P2SBC, 0); ret = p2sb_scan_and_cache(bus, devfn_p2sb); - /* Hide the P2SB device, if it was hidden */ - if (p2sb_hidden_by_bios) - pci_bus_write_config_dword(bus, devfn_p2sb, P2SBC, P2SBC_HIDE); - pci_unlock_rescan_remove(); return ret; -- 2.39.5