1 files changed, 100 insertions, 0 deletions

diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/bios/extdev.c b/drivers/gpu/drm/nouveau/nvkm/subdev/bios/extdev.c
new file mode 100644
index 000000000000..49285d4f7ca5
--- /dev/null
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/bios/extdev.c
@@ -0,0 +1,100 @@
+/*
+ * Copyright 2012 Nouveau Community
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: Martin Peres
+ */
+
+#include <subdev/bios.h>
+#include <subdev/bios/dcb.h>
+#include <subdev/bios/extdev.h>
+
+static u16
+extdev_table(struct nouveau_bios *bios, u8 *ver, u8 *hdr, u8 *len, u8 *cnt)
+{
+        u8  dcb_ver, dcb_hdr, dcb_cnt, dcb_len;
+        u16 dcb, extdev = 0;
+
+        dcb = dcb_table(bios, &dcb_ver, &dcb_hdr, &dcb_cnt, &dcb_len);
+        if (!dcb || (dcb_ver != 0x30 && dcb_ver != 0x40))
+                return 0x0000;
+
+        extdev = nv_ro16(bios, dcb + 18);
+        if (!extdev)
+                return 0x0000;
+
+        *ver = nv_ro08(bios, extdev + 0);
+        *hdr = nv_ro08(bios, extdev + 1);
+        *cnt = nv_ro08(bios, extdev + 2);
+        *len = nv_ro08(bios, extdev + 3);
+
+        return extdev + *hdr;
+}
+
+static u16
+nvbios_extdev_entry(struct nouveau_bios *bios, int idx, u8 *ver, u8 *len)
+{
+        u8 hdr, cnt;
+        u16 extdev = extdev_table(bios, ver, &hdr, len, &cnt);
+        if (extdev && idx < cnt)
+                return extdev + idx * *len;
+        return 0x0000;
+}
+
+static void
+extdev_parse_entry(struct nouveau_bios *bios, u16 offset,
+                          struct nvbios_extdev_func *entry)
+{
+        entry->type = nv_ro08(bios, offset + 0);
+        entry->addr = nv_ro08(bios, offset + 1);
+        entry->bus = (nv_ro08(bios, offset + 2) >> 4) & 1;
+}
+
+int
+nvbios_extdev_parse(struct nouveau_bios *bios, int idx,
+                    struct nvbios_extdev_func *func)
+{
+        u8 ver, len;
+        u16 entry;
+
+        if (!(entry = nvbios_extdev_entry(bios, idx, &ver, &len)))
+                return -EINVAL;
+
+        extdev_parse_entry(bios, entry, func);
+
+        return 0;
+}
+
+int
+nvbios_extdev_find(struct nouveau_bios *bios, enum nvbios_extdev_type type,
+                   struct nvbios_extdev_func *func)
+{
+        u8 ver, len, i;
+        u16 entry;
+
+        i = 0;
+        while ((entry = nvbios_extdev_entry(bios, i++, &ver, &len))) {
+                extdev_parse_entry(bios, entry, func);
+                if (func->type == type)
+                        return 0;
+        }
+
+        return -EINVAL;
+}