On Fri, Oct 5, 2012 at 4:05 PM, Paulo Zanoni <przanoni at gmail.com> wrote: > +static int intel_ddi_get_cdclk_freq(struct drm_i915_private *dev_priv) > +{ > + if (I915_READ(HSW_FUSE_STRAP) & HSW_CDCLK_LIMIT) > + return 450; I don't think reading this fused register is necessary here, it only really matters when you try to set the LCPLL alternate frequency to check if the hardware supports it. I'd just rely on the frequency set bits in LCPLL (if you remove this, it means that the hunk adding the register definition is not needed any more). If you really want to check for consistency, then you could warn if the LCPLL freq has been programmed with 0x1 and HSW_CDCLK_LIMIT is set (in which case the setting will be ignored). But then, there's nothing we can do anyway, so well... -- Damien