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Merge branch 'pci/bjorn-find-next-ext-cap' into next

* pci/bjorn-find-next-ext-cap:
  PCI: Add Vendor-Specific Extended Capability header info
  PCI: Add pci_find_next_ext_capability()

Conflicts:
	drivers/pci/pci.c
Bjorn Helgaas 13 years ago
parent
commit
a28afda8cc
3 changed files with 37 additions and 10 deletions
  1. 30 10
      drivers/pci/pci.c
  2. 1 0
      include/linux/pci.h
  3. 6 0
      include/linux/pci_regs.h

+ 30 - 10
drivers/pci/pci.c

@@ -254,20 +254,17 @@ int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
 }
 
 /**
- * pci_find_ext_capability - Find an extended capability
+ * pci_find_next_ext_capability - Find an extended capability
  * @dev: PCI device to query
+ * @start: address at which to start looking (0 to start at beginning of list)
  * @cap: capability code
  *
- * Returns the address of the requested extended capability structure
+ * Returns the address of the next matching extended capability structure
  * within the device's PCI configuration space or 0 if the device does
- * not support it.  Possible values for @cap:
- *
- *  %PCI_EXT_CAP_ID_ERR		Advanced Error Reporting
- *  %PCI_EXT_CAP_ID_VC		Virtual Channel
- *  %PCI_EXT_CAP_ID_DSN		Device Serial Number
- *  %PCI_EXT_CAP_ID_PWR		Power Budgeting
+ * not support it.  Some capabilities can occur several times, e.g., the
+ * vendor-specific capability, and this provides a way to find them all.
  */
-int pci_find_ext_capability(struct pci_dev *dev, int cap)
+int pci_find_next_ext_capability(struct pci_dev *dev, int start, int cap)
 {
 	u32 header;
 	int ttl;
@@ -279,6 +276,9 @@ int pci_find_ext_capability(struct pci_dev *dev, int cap)
 	if (dev->cfg_size <= PCI_CFG_SPACE_SIZE)
 		return 0;
 
+	if (start)
+		pos = start;
+
 	if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
 		return 0;
 
@@ -290,7 +290,7 @@ int pci_find_ext_capability(struct pci_dev *dev, int cap)
 		return 0;
 
 	while (ttl-- > 0) {
-		if (PCI_EXT_CAP_ID(header) == cap)
+		if (PCI_EXT_CAP_ID(header) == cap && pos != start)
 			return pos;
 
 		pos = PCI_EXT_CAP_NEXT(header);
@@ -303,6 +303,26 @@ int pci_find_ext_capability(struct pci_dev *dev, int cap)
 
 	return 0;
 }
+EXPORT_SYMBOL_GPL(pci_find_next_ext_capability);
+
+/**
+ * pci_find_ext_capability - Find an extended capability
+ * @dev: PCI device to query
+ * @cap: capability code
+ *
+ * Returns the address of the requested extended capability structure
+ * within the device's PCI configuration space or 0 if the device does
+ * not support it.  Possible values for @cap:
+ *
+ *  %PCI_EXT_CAP_ID_ERR		Advanced Error Reporting
+ *  %PCI_EXT_CAP_ID_VC		Virtual Channel
+ *  %PCI_EXT_CAP_ID_DSN		Device Serial Number
+ *  %PCI_EXT_CAP_ID_PWR		Power Budgeting
+ */
+int pci_find_ext_capability(struct pci_dev *dev, int cap)
+{
+	return pci_find_next_ext_capability(dev, 0, cap);
+}
 EXPORT_SYMBOL_GPL(pci_find_ext_capability);
 
 static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)

+ 1 - 0
include/linux/pci.h

@@ -755,6 +755,7 @@ enum pci_lost_interrupt_reason pci_lost_interrupt(struct pci_dev *dev);
 int pci_find_capability(struct pci_dev *dev, int cap);
 int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap);
 int pci_find_ext_capability(struct pci_dev *dev, int cap);
+int pci_find_next_ext_capability(struct pci_dev *dev, int pos, int cap);
 int pci_find_ht_capability(struct pci_dev *dev, int ht_cap);
 int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap);
 struct pci_bus *pci_find_next_bus(const struct pci_bus *from);

+ 6 - 0
include/linux/pci_regs.h

@@ -678,6 +678,12 @@
 #define  PCI_PWR_CAP_BUDGET(x)	((x) & 1)	/* Included in system budget */
 #define PCI_EXT_CAP_PWR_SIZEOF	16
 
+/* Vendor-Specific (VSEC, PCI_EXT_CAP_ID_VNDR) */
+#define PCI_VNDR_HEADER		4	/* Vendor-Specific Header */
+#define  PCI_VNDR_HEADER_ID(x)	((x) & 0xffff)
+#define  PCI_VNDR_HEADER_REV(x)	(((x) >> 16) & 0xf)
+#define  PCI_VNDR_HEADER_LEN(x)	(((x) >> 20) & 0xfff)
+
 /*
  * Hypertransport sub capability types
  *