diff --git a/drivers/gpu/drm/vc4/vc4_hvs.c b/drivers/gpu/drm/vc4/vc4_hvs.c
index e4717ccd0730..f15aba4b81d7 100644
--- a/drivers/gpu/drm/vc4/vc4_hvs.c
+++ b/drivers/gpu/drm/vc4/vc4_hvs.c
@@ -419,12 +419,15 @@ static int vc4_hvs_upload_linear_kernel(struct vc4_hvs *hvs,
 static void vc4_hvs_lut_load(struct vc4_hvs *hvs,
 			     struct vc4_crtc *vc4_crtc)
 {
-	struct drm_device *drm = &hvs->vc4->base;
+	struct vc4_dev *vc4 = hvs->vc4;
+	struct drm_device *drm = &vc4->base;
 	struct drm_crtc *crtc = &vc4_crtc->base;
 	struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
 	int idx;
 	u32 i;
 
+	WARN_ON_ONCE(vc4->gen > VC4_GEN_5);
+
 	if (!drm_dev_enter(drm, &idx))
 		return;
 
@@ -474,6 +477,8 @@ u8 vc4_hvs_get_fifo_frame_count(struct vc4_hvs *hvs, unsigned int fifo)
 	u8 field = 0;
 	int idx;
 
+	WARN_ON_ONCE(vc4->gen > VC4_GEN_6_D);
+
 	if (!drm_dev_enter(drm, &idx))
 		return 0;
 
@@ -530,6 +535,8 @@ int vc4_hvs_get_fifo_from_output(struct vc4_hvs *hvs, unsigned int output)
 	u32 reg;
 	int ret;
 
+	WARN_ON_ONCE(vc4->gen > VC4_GEN_6_D);
+
 	switch (vc4->gen) {
 	case VC4_GEN_4:
 		return output;
@@ -621,6 +628,8 @@ static int vc4_hvs_init_channel(struct vc4_hvs *hvs, struct drm_crtc *crtc,
 	u32 dispctrl;
 	int idx;
 
+	WARN_ON_ONCE(vc4->gen > VC4_GEN_5);
+
 	if (!drm_dev_enter(drm, &idx))
 		return -ENODEV;
 
@@ -682,6 +691,8 @@ static int vc6_hvs_init_channel(struct vc4_hvs *hvs, struct drm_crtc *crtc,
 	u32 disp_ctrl1;
 	int idx;
 
+	WARN_ON_ONCE(vc4->gen < VC4_GEN_6_C);
+
 	if (!drm_dev_enter(drm, &idx))
 		return -ENODEV;
 
@@ -707,9 +718,12 @@ static int vc6_hvs_init_channel(struct vc4_hvs *hvs, struct drm_crtc *crtc,
 
 static void __vc4_hvs_stop_channel(struct vc4_hvs *hvs, unsigned int chan)
 {
-	struct drm_device *drm = &hvs->vc4->base;
+	struct vc4_dev *vc4 = hvs->vc4;
+	struct drm_device *drm = &vc4->base;
 	int idx;
 
+	WARN_ON_ONCE(vc4->gen > VC4_GEN_5);
+
 	if (!drm_dev_enter(drm, &idx))
 		return;
 
@@ -740,6 +754,8 @@ static void __vc6_hvs_stop_channel(struct vc4_hvs *hvs, unsigned int chan)
 	struct drm_device *drm = &vc4->base;
 	int idx;
 
+	WARN_ON_ONCE(vc4->gen < VC4_GEN_6_C);
+
 	if (!drm_dev_enter(drm, &idx))
 		return;
 
@@ -927,6 +943,8 @@ void vc4_hvs_atomic_flush(struct drm_crtc *crtc,
 	bool found = false;
 	int idx;
 
+	WARN_ON_ONCE(vc4->gen > VC4_GEN_6_D);
+
 	if (!drm_dev_enter(dev, &idx)) {
 		vc4_crtc_send_vblank(crtc);
 		return;
@@ -1011,6 +1029,8 @@ void vc4_hvs_atomic_flush(struct drm_crtc *crtc,
 	if (crtc->state->color_mgmt_changed) {
 		u32 dispbkgndx = HVS_READ(SCALER_DISPBKGNDX(channel));
 
+		WARN_ON_ONCE(vc4->gen > VC4_GEN_5);
+
 		if (crtc->state->gamma_lut) {
 			vc4_hvs_update_gamma_lut(hvs, vc4_crtc);
 			dispbkgndx |= SCALER_DISPBKGND_GAMMA;
@@ -1040,6 +1060,8 @@ void vc4_hvs_mask_underrun(struct vc4_hvs *hvs, int channel)
 	u32 dispctrl;
 	int idx;
 
+	WARN_ON(vc4->gen > VC4_GEN_5);
+
 	if (!drm_dev_enter(drm, &idx))
 		return;
 
@@ -1060,6 +1082,8 @@ void vc4_hvs_unmask_underrun(struct vc4_hvs *hvs, int channel)
 	u32 dispctrl;
 	int idx;
 
+	WARN_ON(vc4->gen > VC4_GEN_5);
+
 	if (!drm_dev_enter(drm, &idx))
 		return;
 
@@ -1094,6 +1118,8 @@ static irqreturn_t vc4_hvs_irq_handler(int irq, void *data)
 	u32 status;
 	u32 dspeislur;
 
+	WARN_ON(vc4->gen > VC4_GEN_5);
+
 	/*
 	 * NOTE: We don't need to protect the register access using
 	 * drm_dev_enter() there because the interrupt handler lifetime
diff --git a/drivers/gpu/drm/vc4/vc4_kms.c b/drivers/gpu/drm/vc4/vc4_kms.c
index ce1154c463ef..3f241b15e8be 100644
--- a/drivers/gpu/drm/vc4/vc4_kms.c
+++ b/drivers/gpu/drm/vc4/vc4_kms.c
@@ -138,6 +138,8 @@ vc4_ctm_commit(struct vc4_dev *vc4, struct drm_atomic_state *state)
 	struct vc4_ctm_state *ctm_state = to_vc4_ctm_state(vc4->ctm_manager.state);
 	struct drm_color_ctm *ctm = ctm_state->ctm;
 
+	WARN_ON_ONCE(vc4->gen > VC4_GEN_5);
+
 	if (ctm_state->fifo) {
 		HVS_WRITE(SCALER_OLEDCOEF2,
 			  VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[0]),
@@ -213,6 +215,8 @@ static void vc4_hvs_pv_muxing_commit(struct vc4_dev *vc4,
 	struct drm_crtc *crtc;
 	unsigned int i;
 
+	WARN_ON_ONCE(vc4->gen != VC4_GEN_4);
+
 	for_each_new_crtc_in_state(state, crtc, crtc_state, i) {
 		struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
 		struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc_state);
@@ -256,6 +260,8 @@ static void vc5_hvs_pv_muxing_commit(struct vc4_dev *vc4,
 	unsigned int i;
 	u32 reg;
 
+	WARN_ON_ONCE(vc4->gen != VC4_GEN_5);
+
 	for_each_new_crtc_in_state(state, crtc, crtc_state, i) {
 		struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc_state);
 		struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
diff --git a/drivers/gpu/drm/vc4/vc4_plane.c b/drivers/gpu/drm/vc4/vc4_plane.c
index 205aea3ed419..c084967d3527 100644
--- a/drivers/gpu/drm/vc4/vc4_plane.c
+++ b/drivers/gpu/drm/vc4/vc4_plane.c
@@ -566,8 +566,11 @@ static int vc4_plane_setup_clipping_and_scaling(struct drm_plane_state *state)
 
 static void vc4_write_tpz(struct vc4_plane_state *vc4_state, u32 src, u32 dst)
 {
+	struct vc4_dev *vc4 = to_vc4_dev(vc4_state->base.plane->dev);
 	u32 scale, recip;
 
+	WARN_ON_ONCE(vc4->gen > VC4_GEN_6_D);
+
 	scale = src / dst;
 
 	/* The specs note that while the reciprocal would be defined
@@ -593,10 +596,13 @@ static void vc4_write_tpz(struct vc4_plane_state *vc4_state, u32 src, u32 dst)
 static void vc4_write_ppf(struct vc4_plane_state *vc4_state, u32 src, u32 dst,
 			  u32 xy, int channel)
 {
+	struct vc4_dev *vc4 = to_vc4_dev(vc4_state->base.plane->dev);
 	u32 scale = src / dst;
 	s32 offset, offset2;
 	s32 phase;
 
+	WARN_ON_ONCE(vc4->gen > VC4_GEN_6_D);
+
 	/*
 	 * Start the phase at 1/2 pixel from the 1st pixel at src_x.
 	 * 1/4 pixel for YUV.
@@ -825,8 +831,11 @@ static size_t vc6_upm_size(const struct drm_plane_state *state,
 static void vc4_write_scaling_parameters(struct drm_plane_state *state,
 					 int channel)
 {
+	struct vc4_dev *vc4 = to_vc4_dev(state->plane->dev);
 	struct vc4_plane_state *vc4_state = to_vc4_plane_state(state);
 
+	WARN_ON_ONCE(vc4->gen > VC4_GEN_6_D);
+
 	/* Ch0 H-PPF Word 0: Scaling Parameters */
 	if (vc4_state->x_scaling[channel] == VC4_SCALING_PPF) {
 		vc4_write_ppf(vc4_state, vc4_state->src_w[channel],
@@ -1113,6 +1122,11 @@ static const u32 colorspace_coeffs[2][DRM_COLOR_ENCODING_MAX][3] = {
 
 static u32 vc4_hvs4_get_alpha_blend_mode(struct drm_plane_state *state)
 {
+	struct drm_device *dev = state->state->dev;
+	struct vc4_dev *vc4 = to_vc4_dev(dev);
+
+	WARN_ON_ONCE(vc4->gen != VC4_GEN_4);
+
 	if (!state->fb->format->has_alpha)
 		return VC4_SET_FIELD(SCALER_POS2_ALPHA_MODE_FIXED,
 				     SCALER_POS2_ALPHA_MODE);
@@ -1137,6 +1151,9 @@ static u32 vc4_hvs5_get_alpha_blend_mode(struct drm_plane_state *state)
 	struct drm_device *dev = state->state->dev;
 	struct vc4_dev *vc4 = to_vc4_dev(dev);
 
+	WARN_ON_ONCE(vc4->gen != VC4_GEN_5 && vc4->gen != VC4_GEN_6_C &&
+		     vc4->gen != VC4_GEN_6_D);
+
 	switch (vc4->gen) {
 	default:
 	case VC4_GEN_5:
