Did you install the firmware first? It seems odd that wsdisplay is not listed in your dmesg, is that just an omission on your side?
Anyway to get some more information you could build a kernel with: Index: drmP.h =================================================================== RCS file: /cvs/src/sys/dev/pci/drm/drmP.h,v retrieving revision 1.144 diff -u -p -r1.144 drmP.h --- drmP.h 14 Aug 2013 02:49:19 -0000 1.144 +++ drmP.h 17 Aug 2013 09:01:15 -0000 @@ -74,6 +74,8 @@ #include "drm_atomic.h" #include "agp.h" +#define DRMDEBUG + #define DRM_DEBUGBITS_DEBUG 0x1 #define DRM_DEBUGBITS_KMS 0x2 #define DRM_DEBUGBITS_FAILED_IOCTL 0x4
