On 2013/7/9 16:09, Gu Zheng wrote: > On 07/09/2013 03:55 PM, Yijing Wang wrote: > >> Introduce PCIe Ext Capability Device Serial Number support, >> so we can use the unique device serial number to identify >> the physical device. During system suspend, if the PCIe >> device was removed and inserted a new same device, after >> system resume there is no good way to identify it, maybe >> Device Serial Number is a good choice if device support. > > Nice idea! > > Regards, > Gu > >> >> Signed-off-by: Yijing Wang <[email protected]> > > > Reviewed-by: Gu Zheng <[email protected]>
Thanks very much! Yijing. > >> Cc: "Rafael J. Wysocki" <[email protected]> >> Cc: Oliver Neukum <[email protected]> >> Cc: Paul Bolle <[email protected]> >> Cc: Gu Zheng <[email protected]> >> Cc: [email protected] >> --- >> drivers/pci/pci.c | 33 +++++++++++++++++++++++++++++++++ >> drivers/pci/pci.h | 1 + >> drivers/pci/probe.c | 3 +++ >> include/linux/pci.h | 4 ++++ >> 4 files changed, 41 insertions(+), 0 deletions(-) >> >> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c >> index e37fea6..d08df2b 100644 >> --- a/drivers/pci/pci.c >> +++ b/drivers/pci/pci.c >> @@ -2048,6 +2048,39 @@ void pci_free_cap_save_buffers(struct pci_dev *dev) >> } >> >> /** >> + * pci_get_dsn - get device serial number >> + * @dev: the PCI device >> + * @sn: saved device serial number >> + */ >> +void pci_get_dsn(struct pci_dev *dev, u64 *sn) >> +{ >> + int pos; >> + u32 lo, hi; >> + >> + if (!pci_is_pcie(dev)) >> + goto out; >> + >> + pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_DSN); >> + if (!pos) >> + goto out; >> + >> + pci_read_config_dword(dev, pos + 4, &lo); >> + pci_read_config_dword(dev, pos + 8, &hi); >> + *sn = ((u64)hi << 32) | lo; >> + return; >> + >> +out: >> + *sn = 0; >> + return; >> +} >> +EXPORT_SYMBOL(pci_get_dsn); >> + >> +void pci_dsn_init(struct pci_dev *dev) >> +{ >> + return pci_get_dsn(dev, &dev->sn); >> +} >> + >> +/** >> * pci_configure_ari - enable or disable ARI forwarding >> * @dev: the PCI device >> * >> diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h >> index 68678ed..f626006 100644 >> --- a/drivers/pci/pci.h >> +++ b/drivers/pci/pci.h >> @@ -202,6 +202,7 @@ int __pci_read_base(struct pci_dev *dev, enum >> pci_bar_type type, >> struct resource *res, unsigned int reg); >> int pci_resource_bar(struct pci_dev *dev, int resno, enum pci_bar_type >> *type); >> void pci_configure_ari(struct pci_dev *dev); >> +void pci_dsn_init(struct pci_dev *dev); >> >> /** >> * pci_ari_enabled - query ARI forwarding status >> diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c >> index 46ada5c..d4c6e7e 100644 >> --- a/drivers/pci/probe.c >> +++ b/drivers/pci/probe.c >> @@ -1322,6 +1322,9 @@ static void pci_init_capabilities(struct pci_dev *dev) >> /* Power Management */ >> pci_pm_init(dev); >> >> + /* Device Serial Number */ >> + pci_dsn_init(dev); >> + >> /* Vital Product Data */ >> pci_vpd_pci22_init(dev); >> >> diff --git a/include/linux/pci.h b/include/linux/pci.h >> index 0fd1f15..59cd205 100644 >> --- a/include/linux/pci.h >> +++ b/include/linux/pci.h >> @@ -342,6 +342,7 @@ struct pci_dev { >> struct list_head msi_list; >> struct kset *msi_kset; >> #endif >> + u64 sn; /* device serieal number, 0 if not support */ >> struct pci_vpd *vpd; >> #ifdef CONFIG_PCI_ATS >> union { >> @@ -995,6 +996,9 @@ ssize_t pci_read_vpd(struct pci_dev *dev, loff_t pos, >> size_t count, void *buf); >> ssize_t pci_write_vpd(struct pci_dev *dev, loff_t pos, size_t count, const >> void *buf); >> int pci_vpd_truncate(struct pci_dev *dev, size_t size); >> >> +/* Device Serial Number */ >> +void pci_get_dsn(struct pci_dev *dev, u64 *sn); >> + >> /* Helper functions for low-level code (drivers/pci/setup-[bus,res].c) */ >> resource_size_t pcibios_retrieve_fw_addr(struct pci_dev *dev, int idx); >> void pci_bus_assign_resources(const struct pci_bus *bus); > > > > . > -- Thanks! Yijing -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
