[PATCH v3 09/27] ocxl: Save the device serial number in ocxl_fn
From: Alastair D'Silva <hidden>
Date: 2020-02-21 03:28:31
Also in:
linux-mm, lkml, nvdimm
Subsystem:
char and misc drivers, ocxl (open coherent accelerator processor interface opencapi) driver, the rest · Maintainers:
Arnd Bergmann, Greg Kroah-Hartman, Mahesh J Salgaonkar, Linus Torvalds
From: Alastair D'Silva <redacted> This patch retrieves the serial number of the card and makes it available to consumers of the ocxl driver via the ocxl_fn struct. Signed-off-by: Alastair D'Silva <redacted> Acked-by: Frederic Barrat <redacted> Acked-by: Andrew Donnellan <redacted> --- drivers/misc/ocxl/config.c | 46 ++++++++++++++++++++++++++++++++++++++ include/misc/ocxl.h | 1 + 2 files changed, 47 insertions(+)
diff --git a/drivers/misc/ocxl/config.c b/drivers/misc/ocxl/config.c
index 701ae6216abf..ce33fafa7b50 100644
--- a/drivers/misc/ocxl/config.c
+++ b/drivers/misc/ocxl/config.c@@ -71,6 +71,51 @@ static int find_dvsec_afu_ctrl(struct pci_dev *dev, u8 afu_idx) return 0; } +/** + * get_function_0() - Find a related PCI device (function 0) + * @device: PCI device to match + * + * Returns a pointer to the related device, or null if not found + */ +static struct pci_dev *get_function_0(struct pci_dev *dev) +{ + unsigned int devfn = PCI_DEVFN(PCI_SLOT(dev->devfn), 0); + + return pci_get_domain_bus_and_slot(pci_domain_nr(dev->bus), + dev->bus->number, devfn); +} + +static void read_serial(struct pci_dev *dev, struct ocxl_fn_config *fn) +{ + u32 low, high; + int pos; + + pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_DSN); + if (pos) { + pci_read_config_dword(dev, pos + 0x04, &low); + pci_read_config_dword(dev, pos + 0x08, &high); + + fn->serial = low | ((u64)high) << 32; + + return; + } + + if (PCI_FUNC(dev->devfn) != 0) { + struct pci_dev *related = get_function_0(dev); + + if (!related) { + fn->serial = 0; + return; + } + + read_serial(related, fn); + pci_dev_put(related); + return; + } + + fn->serial = 0; +} + static void read_pasid(struct pci_dev *dev, struct ocxl_fn_config *fn) { u16 val;
@@ -208,6 +253,7 @@ int ocxl_config_read_function(struct pci_dev *dev, struct ocxl_fn_config *fn) int rc; read_pasid(dev, fn); + read_serial(dev, fn); rc = read_dvsec_tl(dev, fn); if (rc) {
diff --git a/include/misc/ocxl.h b/include/misc/ocxl.h
index d8b0b4d46bfb..b8514dc64bd0 100644
--- a/include/misc/ocxl.h
+++ b/include/misc/ocxl.h@@ -46,6 +46,7 @@ struct ocxl_fn_config { int dvsec_afu_info_pos; /* offset of the AFU information DVSEC */ s8 max_pasid_log; s8 max_afu_index; + u64 serial; }; enum ocxl_endian {
--
2.24.1