r277959 breaks X display on IvyBridge mobile GT2 IG

Hi

With this commit my display blanks and never lights up when X starts.

[zen] /usr/src # svn diff -r 277958:277959
Index: sys/dev/drm2/i915/intel_display.c
===================================================================
--- sys/dev/drm2/i915/intel_display.c   (revision 277958)
+++ sys/dev/drm2/i915/intel_display.c   (revision 277959)
_at__at_ -6995,7 +6995,7 _at__at_
         */
        I915_WRITE(BLC_PWM_CPU_CTL2, PWM_ENABLE);
        I915_WRITE(BLC_PWM_CPU_CTL, 0);
-       I915_WRITE(BLC_PWM_PCH_CTL1, PWM_ENABLE | (1<<30));
+       I915_WRITE(BLC_PWM_PCH_CTL1, PWM_ENABLE);
 }

 void intel_modeset_init_hw(struct drm_device *dev)


vgapci0_at_pci0:0:2:0:     class=0x030000 card=0x15171043 chip=0x01668086 rev=0x09 
hdr=0x00
    vendor     = 'Intel Corporation'
    device     = '3rd Gen Core processor Graphics Controller'
    class      = display
    subclass   = VGA
    cap 05[90] = MSI supports 1 message enabled with 1 message
    cap 01[d0] = powerspec 2  supports D0 D3  current D0
    cap 13[a4] = PCI Advanced Features: FLR TP

Ian

-- 
Ian Freislich