drm/meson: add mode selection limits against specific SoC revisions

The Amlogic S805X/Y uses the same die as the S905X, but with more
limited graphics capabilities.

This adds a soc version detection adding specific limitations on the HDMI
mode selections.

Here, we limit to HDMI 1.2a max HDMI PHY clock frequency.

Changes sinces v1:
- Moved frequency check in the vclk code, and also checks DMT modes

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
[narmstrong: fixed commit message with HDMI 1.2a instead of HDMI 1.3a]
Link: https://patchwork.freedesktop.org/patch/msgid/20200428092147.13698-1-narmstrong@baylibre.com

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/gpu/drm/meson/meson_drv.h b/drivers/gpu/drm/meson/meson_drv.h
index 04fdf3826643..5b23704a80d6 100644
--- a/drivers/gpu/drm/meson/meson_drv.h
+++ b/drivers/gpu/drm/meson/meson_drv.h
@@ -30,6 +30,10 @@ struct meson_drm_match_data {
 	struct meson_afbcd_ops *afbcd_ops;
 };
 
+struct meson_drm_soc_limits {
+	unsigned int max_hdmi_phy_freq;
+};
+
 struct meson_drm {
 	struct device *dev;
 	enum vpu_compatible compat;
@@ -48,6 +52,8 @@ struct meson_drm {
 	struct drm_plane *primary_plane;
 	struct drm_plane *overlay_plane;
 
+	const struct meson_drm_soc_limits *limits;
+
 	/* Components Data */
 	struct {
 		bool osd1_enabled;