pci: Add PCI LRDT tag size and section size

This patch adds a preprocessor constant to describe the PCI VPD large
resource data type tag size and an inline function to extract the large
resource section size from the large resource data type tag.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 14 insertions, 0 deletions

diff --git a/include/linux/pci.h b/include/linux/pci.h
index e2575f86133a..6f62a499023f 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1349,5 +1349,19 @@ static inline bool pci_is_pcie(struct pci_dev *dev)
 
 void pci_request_acs(void);
 
+
+#define PCI_VPD_LRDT_TAG_SIZE   3
+
+/**
+ * pci_vpd_lrdt_size - Extracts the Large Resource Data Type length
+ * @lrdt: Pointer to the beginning of the Large Resource Data Type tag
+ *
+ * Returns the extracted Large Resource Data Type length.
+ */
+static inline u16 pci_vpd_lrdt_size(const u8 *lrdt)
+{
+        return (u16)lrdt[1] + ((u16)lrdt[2] << 8);
+}
+
 #endif /* __KERNEL__ */
 #endif /* LINUX_PCI_H */