drm/rockchip: dw_hdmi: Add max_tmds_clock validation

Add max_tmds_clock validation to prepare for additions and changes to
the MPLL config table. Use the same rate restrictions that is currently
applied.

The rate limit for RK3288, RK3399 and RK3568 is based on current mpll
table. The rate limit for RK3228 and RK3328 is based on the
inno-hdmi-phy pre-pll table.
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20240615170417.3134517-7-jonas@kwiboo.se

drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c

@@ -61,11 +61,13 @@
  * @lcdsel_grf_reg: grf register offset of lcdc select
  * @lcdsel_big: reg value of selecting vop big for HDMI
  * @lcdsel_lit: reg value of selecting vop little for HDMI
+ * @max_tmds_clock: maximum TMDS clock rate supported
  */
 struct rockchip_hdmi_chip_data {
 	int	lcdsel_grf_reg;
 	u32	lcdsel_big;
 	u32	lcdsel_lit;
+	int	max_tmds_clock;
 };
 
 struct rockchip_hdmi {
@@ -254,6 +256,10 @@ dw_hdmi_rockchip_mode_valid(struct dw_hdmi *dw_hdmi, void *data,
 	bool exact_match = hdmi->plat_data->phy_force_vendor;
 	int i;
 
+	if (hdmi->chip_data->max_tmds_clock &&
+	    mode->clock > hdmi->chip_data->max_tmds_clock)
+		return MODE_CLOCK_HIGH;
+
 	if (hdmi->ref_clk) {
 		int rpclk = clk_round_rate(hdmi->ref_clk, pclk);
 
@@ -444,6 +450,7 @@ static const struct dw_hdmi_phy_ops rk3228_hdmi_phy_ops = {
 
 static struct rockchip_hdmi_chip_data rk3228_chip_data = {
 	.lcdsel_grf_reg = -1,
+	.max_tmds_clock = 594000,
 };
 
 static const struct dw_hdmi_plat_data rk3228_hdmi_drv_data = {
@@ -458,6 +465,7 @@ static struct rockchip_hdmi_chip_data rk3288_chip_data = {
 	.lcdsel_grf_reg = RK3288_GRF_SOC_CON6,
 	.lcdsel_big = HIWORD_UPDATE(0, RK3288_HDMI_LCDC_SEL),
 	.lcdsel_lit = HIWORD_UPDATE(RK3288_HDMI_LCDC_SEL, RK3288_HDMI_LCDC_SEL),
+	.max_tmds_clock = 340000,
 };
 
 static const struct dw_hdmi_plat_data rk3288_hdmi_drv_data = {
@@ -478,6 +486,7 @@ static const struct dw_hdmi_phy_ops rk3328_hdmi_phy_ops = {
 
 static struct rockchip_hdmi_chip_data rk3328_chip_data = {
 	.lcdsel_grf_reg = -1,
+	.max_tmds_clock = 594000,
 };
 
 static const struct dw_hdmi_plat_data rk3328_hdmi_drv_data = {
@@ -493,6 +502,7 @@ static struct rockchip_hdmi_chip_data rk3399_chip_data = {
 	.lcdsel_grf_reg = RK3399_GRF_SOC_CON20,
 	.lcdsel_big = HIWORD_UPDATE(0, RK3399_HDMI_LCDC_SEL),
 	.lcdsel_lit = HIWORD_UPDATE(RK3399_HDMI_LCDC_SEL, RK3399_HDMI_LCDC_SEL),
+	.max_tmds_clock = 340000,
 };
 
 static const struct dw_hdmi_plat_data rk3399_hdmi_drv_data = {
@@ -506,6 +516,7 @@ static const struct dw_hdmi_plat_data rk3399_hdmi_drv_data = {
 
 static struct rockchip_hdmi_chip_data rk3568_chip_data = {
 	.lcdsel_grf_reg = -1,
+	.max_tmds_clock = 340000,
 };
 
 static const struct dw_hdmi_plat_data rk3568_hdmi_drv_data = {