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author | Linus Torvalds <torvalds@linux-foundation.org> | 2024-12-16 10:01:57 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2024-12-16 10:01:57 -0800 |
commit | dc690bc256edd9da6596fccf978327309173f44a (patch) | |
tree | 2f34f92893bdcf7688384e0d339b083d940a400e /drivers/platform/x86/p2sb.c | |
parent | 78d4f34e2115b517bcbfe7ec0d018bbbb6f9b0b8 (diff) | |
parent | 83848e37f6ee80f60b04139fefdfa1bde4aaa826 (diff) | |
download | linux-dc690bc256edd9da6596fccf978327309173f44a.tar.gz linux-dc690bc256edd9da6596fccf978327309173f44a.tar.bz2 linux-dc690bc256edd9da6596fccf978327309173f44a.zip |
Merge tag 'platform-drivers-x86-v6.13-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86
Pull x86 platform driver fixes from Ilpo Järvinen:
- alienware-wmi:
- Add support for Alienware m16 R1 AMD
- Do not setup legacy LED control with X and G Series
- intel/ifs: Clearwater Forest support
- intel/vsec: Panther Lake support
- p2sb: Do not hide the device if BIOS left it unhidden
- touchscreen_dmi: Add SARY Tab 3 tablet information
* tag 'platform-drivers-x86-v6.13-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86:
platform/x86/intel/vsec: Add support for Panther Lake
platform/x86/intel/ifs: Add Clearwater Forest to CPU support list
platform/x86: touchscreen_dmi: Add info for SARY Tab 3 tablet
p2sb: Do not scan and remove the P2SB device when it is unhidden
p2sb: Move P2SB hide and unhide code to p2sb_scan_and_cache()
p2sb: Introduce the global flag p2sb_hidden_by_bios
p2sb: Factor out p2sb_read_from_cache()
alienware-wmi: Adds support to Alienware m16 R1 AMD
alienware-wmi: Fix X Series and G Series quirks
Diffstat (limited to 'drivers/platform/x86/p2sb.c')
-rw-r--r-- | drivers/platform/x86/p2sb.c | 77 |
1 files changed, 55 insertions, 22 deletions
diff --git a/drivers/platform/x86/p2sb.c b/drivers/platform/x86/p2sb.c index d51eb0db0626..cbbb0f809704 100644 --- a/drivers/platform/x86/p2sb.c +++ b/drivers/platform/x86/p2sb.c @@ -43,6 +43,7 @@ struct p2sb_res_cache { }; static struct p2sb_res_cache p2sb_resources[NR_P2SB_RES_CACHE]; +static bool p2sb_hidden_by_bios; static void p2sb_get_devfn(unsigned int *devfn) { @@ -97,6 +98,12 @@ 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. + */ + 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 +111,8 @@ 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); + pci_bus_write_config_dword(bus, devfn, P2SBC, P2SBC_HIDE); + if (!p2sb_valid_resource(&p2sb_resources[PCI_FUNC(devfn)].res)) return -ENOENT; @@ -129,7 +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); @@ -152,22 +161,53 @@ static int p2sb_cache_resources(void) */ pci_lock_rescan_remove(); + pci_bus_read_config_dword(bus, devfn_p2sb, P2SBC, &value); + p2sb_hidden_by_bios = value & P2SBC_HIDE; + /* - * 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 the BIOS does not hide the P2SB device then its resources + * are accesilble. Cache them only if the P2SB device is hidden. */ - pci_bus_read_config_dword(bus, devfn_p2sb, P2SBC, &value); - if (value & P2SBC_HIDE) - pci_bus_write_config_dword(bus, devfn_p2sb, P2SBC, 0); + if (p2sb_hidden_by_bios) + ret = p2sb_scan_and_cache(bus, devfn_p2sb); - ret = p2sb_scan_and_cache(bus, devfn_p2sb); + pci_unlock_rescan_remove(); - /* Hide the P2SB device, if it was hidden */ - if (value & P2SBC_HIDE) - pci_bus_write_config_dword(bus, devfn_p2sb, P2SBC, P2SBC_HIDE); + return ret; +} - pci_unlock_rescan_remove(); +static int p2sb_read_from_cache(struct pci_bus *bus, unsigned int devfn, + struct resource *mem) +{ + struct p2sb_res_cache *cache = &p2sb_resources[PCI_FUNC(devfn)]; + + if (cache->bus_dev_id != bus->dev.id) + return -ENODEV; + + if (!p2sb_valid_resource(&cache->res)) + return -ENOENT; + + memcpy(mem, &cache->res, sizeof(*mem)); + + 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; } @@ -188,8 +228,6 @@ static int p2sb_cache_resources(void) */ int p2sb_bar(struct pci_bus *bus, unsigned int devfn, struct resource *mem) { - struct p2sb_res_cache *cache; - bus = p2sb_get_bus(bus); if (!bus) return -ENODEV; @@ -197,15 +235,10 @@ int p2sb_bar(struct pci_bus *bus, unsigned int devfn, struct resource *mem) if (!devfn) p2sb_get_devfn(&devfn); - cache = &p2sb_resources[PCI_FUNC(devfn)]; - if (cache->bus_dev_id != bus->dev.id) - return -ENODEV; + if (p2sb_hidden_by_bios) + return p2sb_read_from_cache(bus, devfn, mem); - if (!p2sb_valid_resource(&cache->res)) - return -ENOENT; - - memcpy(mem, &cache->res, sizeof(*mem)); - return 0; + return p2sb_read_from_dev(bus, devfn, mem); } EXPORT_SYMBOL_GPL(p2sb_bar); |