struct

The actual value of the integral part of the numerator.

Amlogic-provided code requires this value be in the range [2, 511] on all

Fuchsia-supported platforms (A311D, S905D2, S905D3, and T931). However,

the datasheet mentions that this field only uses bit 7-0, so this field

must not exceed 255.

Also note that on all Fuchsia-supported platforms, the crystal oscillator

is fixed to 24MHz, and the frequency of the HDMI PLL VCO cannot exceed

6GHz; so in this specific case, the maximum allowed `numerator_integer`

should be

6000 / 24 + 2 = 251

when `numerator_fraction`

<

= -1.

Given all the constraints above, for maximum convenience, compatibility and

extensibility (to use other oscillators), we keep the original bit

definition of the field (bits 7-0), and require the value must be in the

range of [2, 255]. Drivers must check that the final VCO frequency does

not exceed the 6GHz hardware limit.

It's preferred to use `SetNumeratorInteger()` to direct field manipulation.