clk: meson: meson8b: add the fractional divider for vid_pll_dco

This "vid_pll_dco" (which should be named HDMI_PLL or - as the datasheet
calls it - HPLL) has a 12-bit wide fractional parameter at
HHI_VID_PLL_CNTL2[11:0]. Add this so we correctly calculate the rate of
this PLL when u-boot is configured for a video mode which uses this
fractional parameter.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181202214220.7715-3-martin.blumenstingl@googlemail.com

drivers/clk/meson/meson8b.c

@@ -137,6 +137,11 @@ static struct clk_regmap meson8b_vid_pll_dco = {
 			.shift   = 10,
 			.width   = 5,
 		},
+		.frac = {
+			.reg_off = HHI_VID_PLL_CNTL2,
+			.shift   = 0,
+			.width   = 12,
+		},
 		.l = {
 			.reg_off = HHI_VID_PLL_CNTL,
 			.shift   = 31,

drivers/clk/meson/meson8b.h

@@ -33,6 +33,7 @@
 #define HHI_MPLL_CNTL			0x280 /* 0xa0 offset in data sheet */
 #define HHI_SYS_PLL_CNTL		0x300 /* 0xc0 offset in data sheet */
 #define HHI_VID_PLL_CNTL		0x320 /* 0xc8 offset in data sheet */
+#define HHI_VID_PLL_CNTL2		0x324 /* 0xc9 offset in data sheet */
 
 /*
  * MPLL register offeset taken from the S905 datasheet. Vendor kernel source