drm/nv4c/bios: disallow retrieving from prom on nv4x igp's

Suggested-by: Marcin Kościelnicki <koriakin@0x04.net>
Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/gpu/drm/nouveau/core/subdev/bios/base.c b/drivers/gpu/drm/nouveau/core/subdev/bios/base.c
index aa0fbbec7f08..ef0c9c4a8cc3 100644
--- a/drivers/gpu/drm/nouveau/core/subdev/bios/base.c
+++ b/drivers/gpu/drm/nouveau/core/subdev/bios/base.c
@@ -130,6 +130,10 @@ nouveau_bios_shadow_prom(struct nouveau_bios *bios)
         u16 pcir;
         int i;
 
+        /* there is no prom on nv4x IGP's */
+        if (device->card_type == NV_40 && device->chipset >= 0x4c)
+                return;
+
         /* enable access to rom */
         if (device->card_type >= NV_50)
                 pcireg = 0x088050;