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-rw-r--r--contrib/syslinux-4.02/gpxe/src/drivers/bus/pciextra.c86
1 files changed, 86 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/gpxe/src/drivers/bus/pciextra.c b/contrib/syslinux-4.02/gpxe/src/drivers/bus/pciextra.c
new file mode 100644
index 0000000..74c4099
--- /dev/null
+++ b/contrib/syslinux-4.02/gpxe/src/drivers/bus/pciextra.c
@@ -0,0 +1,86 @@
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <stdint.h>
+#include <gpxe/pci.h>
+
+/**
+ * Look for a PCI capability
+ *
+ * @v pci PCI device to query
+ * @v cap Capability code
+ * @ret address Address of capability, or 0 if not found
+ *
+ * Determine whether or not a device supports a given PCI capability.
+ * Returns the address of the requested capability structure within
+ * the device's PCI configuration space, or 0 if the device does not
+ * support it.
+ */
+int pci_find_capability ( struct pci_device *pci, int cap ) {
+ uint16_t status;
+ uint8_t pos, id;
+ uint8_t hdr_type;
+ int ttl = 48;
+
+ pci_read_config_word ( pci, PCI_STATUS, &status );
+ if ( ! ( status & PCI_STATUS_CAP_LIST ) )
+ return 0;
+
+ pci_read_config_byte ( pci, PCI_HEADER_TYPE, &hdr_type );
+ switch ( hdr_type & 0x7F ) {
+ case PCI_HEADER_TYPE_NORMAL:
+ case PCI_HEADER_TYPE_BRIDGE:
+ default:
+ pci_read_config_byte ( pci, PCI_CAPABILITY_LIST, &pos );
+ break;
+ case PCI_HEADER_TYPE_CARDBUS:
+ pci_read_config_byte ( pci, PCI_CB_CAPABILITY_LIST, &pos );
+ break;
+ }
+ while ( ttl-- && pos >= 0x40 ) {
+ pos &= ~3;
+ pci_read_config_byte ( pci, pos + PCI_CAP_LIST_ID, &id );
+ DBG ( "PCI Capability: %d\n", id );
+ if ( id == 0xff )
+ break;
+ if ( id == cap )
+ return pos;
+ pci_read_config_byte ( pci, pos + PCI_CAP_LIST_NEXT, &pos );
+ }
+ return 0;
+}
+
+/**
+ * Find the size of a PCI BAR
+ *
+ * @v pci PCI device
+ * @v reg PCI register number
+ * @ret size BAR size
+ *
+ * It should not be necessary for any Etherboot code to call this
+ * function.
+ */
+unsigned long pci_bar_size ( struct pci_device *pci, unsigned int reg ) {
+ uint16_t cmd;
+ uint32_t start, size;
+
+ /* Save the original command register */
+ pci_read_config_word ( pci, PCI_COMMAND, &cmd );
+ /* Save the original bar */
+ pci_read_config_dword ( pci, reg, &start );
+ /* Compute which bits can be set */
+ pci_write_config_dword ( pci, reg, ~0 );
+ pci_read_config_dword ( pci, reg, &size );
+ /* Restore the original size */
+ pci_write_config_dword ( pci, reg, start );
+ /* Find the significant bits */
+ /* Restore the original command register. This reenables decoding. */
+ pci_write_config_word ( pci, PCI_COMMAND, cmd );
+ if ( start & PCI_BASE_ADDRESS_SPACE_IO ) {
+ size &= PCI_BASE_ADDRESS_IO_MASK;
+ } else {
+ size &= PCI_BASE_ADDRESS_MEM_MASK;
+ }
+ /* Find the lowest bit set */
+ size = size & ~( size - 1 );
+ return size;
+}