efi_loader: complete EFI_DEVICE_PATH_UTILITIES_PROTOCOL

[u-boot] / lib / efi_loader / efi_device_path_utilities.c

diff --git a/lib/efi_loader/efi_device_path_utilities.c b/lib/efi_loader/efi_device_path_utilities.c
index e73188b242ccd6bc8ae68147f289ef0c954e720d..0ada2111db980a95db2a4c1d15c75721d717b5dd 100644 (file)
--- a/lib/efi_loader/efi_device_path_utilities.c
+++ b/lib/efi_loader/efi_device_path_utilities.c
@@ -12,62 +12,158 @@
 const efi_guid_t efi_guid_device_path_utilities_protocol =
                EFI_DEVICE_PATH_UTILITIES_PROTOCOL_GUID;
 
+/*
+ * Get size of a device path.
+ *
+ * This function implements the GetDevicePathSize service of the device path
+ * utilities protocol. The device path length includes the end of path tag
+ * which may be an instance end.
+ *
+ * See the Unified Extensible Firmware Interface (UEFI) specification
+ * for details.
+ *
+ * @device_path                device path
+ * @return             size in bytes
+ */
 static efi_uintn_t EFIAPI get_device_path_size(
        const struct efi_device_path *device_path)
 {
        efi_uintn_t sz = 0;
 
-       EFI_ENTRY("%p", device_path);
+       EFI_ENTRY("%pD", device_path);
        /* size includes the END node: */
        if (device_path)
                sz = efi_dp_size(device_path) + sizeof(struct efi_device_path);
        return EFI_EXIT(sz);
 }
 
+/*
+ * Duplicate a device path.
+ *
+ * This function implements the DuplicateDevicePath service of the device path
+ * utilities protocol.
+ *
+ * The UEFI spec does not indicate what happens to the end tag. We follow the
+ * EDK2 logic: In case the device path ends with an end of instance tag, the
+ * copy will also end with an end of instance tag.
+ *
+ * See the Unified Extensible Firmware Interface (UEFI) specification
+ * for details.
+ *
+ * @device_path                device path
+ * @return             copy of the device path
+ */
 static struct efi_device_path * EFIAPI duplicate_device_path(
        const struct efi_device_path *device_path)
 {
-       EFI_ENTRY("%p", device_path);
+       EFI_ENTRY("%pD", device_path);
        return EFI_EXIT(efi_dp_dup(device_path));
 }
 
+/*
+ * Append device path.
+ *
+ * This function implements the AppendDevicePath service of the device path
+ * utilities protocol.
+ *
+ * See the Unified Extensible Firmware Interface (UEFI) specification
+ * for details.
+ *
+ * @src1               1st device path
+ * @src2               2nd device path
+ * @return             concatenated device path
+ */
 static struct efi_device_path * EFIAPI append_device_path(
        const struct efi_device_path *src1,
        const struct efi_device_path *src2)
 {
-       EFI_ENTRY("%p, %p", src1, src2);
+       EFI_ENTRY("%pD, %pD", src1, src2);
        return EFI_EXIT(efi_dp_append(src1, src2));
 }
 
+/*
+ * Append device path node.
+ *
+ * This function implements the AppendDeviceNode service of the device path
+ * utilities protocol.
+ *
+ * See the Unified Extensible Firmware Interface (UEFI) specification
+ * for details.
+ *
+ * @device_path                device path
+ * @device_node                device node
+ * @return             concatenated device path
+ */
 static struct efi_device_path * EFIAPI append_device_node(
        const struct efi_device_path *device_path,
        const struct efi_device_path *device_node)
 {
-       EFI_ENTRY("%p, %p", device_path, device_node);
+       EFI_ENTRY("%pD, %p", device_path, device_node);
        return EFI_EXIT(efi_dp_append_node(device_path, device_node));
 }
 
+/*
+ * Append device path instance.
+ *
+ * This function implements the AppendDevicePathInstance service of the device
+ * path utilities protocol.
+ *
+ * See the Unified Extensible Firmware Interface (UEFI) specification
+ * for details.
+ *
+ * @device_path                        1st device path
+ * @device_path_instance       2nd device path
+ * @return                     concatenated device path
+ */
 static struct efi_device_path * EFIAPI append_device_path_instance(
        const struct efi_device_path *device_path,
        const struct efi_device_path *device_path_instance)
 {
-       EFI_ENTRY("%p, %p", device_path, device_path_instance);
-       return EFI_EXIT(NULL);
+       EFI_ENTRY("%pD, %pD", device_path, device_path_instance);
+       return EFI_EXIT(efi_dp_append_instance(device_path,
+                                              device_path_instance));
 }
 
+/*
+ * Get next device path instance.
+ *
+ * This function implements the GetNextDevicePathInstance service of the device
+ * path utilities protocol.
+ *
+ * See the Unified Extensible Firmware Interface (UEFI) specification
+ * for details.
+ *
+ * @device_path_instance       next device path instance
+ * @device_path_instance_size  size of the device path instance
+ * @return                     concatenated device path
+ */
 static struct efi_device_path * EFIAPI get_next_device_path_instance(
        struct efi_device_path **device_path_instance,
        efi_uintn_t *device_path_instance_size)
 {
-       EFI_ENTRY("%p, %p", device_path_instance, device_path_instance_size);
-       return EFI_EXIT(NULL);
+       EFI_ENTRY("%pD, %p", device_path_instance, device_path_instance_size);
+       return EFI_EXIT(efi_dp_get_next_instance(device_path_instance,
+                                                device_path_instance_size));
 }
 
+/*
+ * Check if a device path contains more than one instance.
+ *
+ * This function implements the AppendDeviceNode service of the device path
+ * utilities protocol.
+ *
+ * See the Unified Extensible Firmware Interface (UEFI) specification
+ * for details.
+ *
+ * @device_path                device path
+ * @device_node                device node
+ * @return             concatenated device path
+ */
 static bool EFIAPI is_device_path_multi_instance(
        const struct efi_device_path *device_path)
 {
-       EFI_ENTRY("%p", device_path);
-       return EFI_EXIT(false);
+       EFI_ENTRY("%pD", device_path);
+       return EFI_EXIT(efi_dp_is_multi_instance(device_path));
 }
 
 /*