BXT_DSI_PLL_CTL
val = intel_de_read(display, BXT_DSI_PLL_CTL);
config->dsi_pll.ctrl = intel_de_read(display, BXT_DSI_PLL_CTL);
intel_de_write(display, BXT_DSI_PLL_CTL, config->dsi_pll.ctrl);
intel_de_posting_read(display, BXT_DSI_PLL_CTL);
MMIO_D(BXT_DSI_PLL_CTL);