[PATCH 10/14] drm/imx: dc-lb: Support getting secondary input selection

Liu Ying
2025-07-04T10:32:49Z

Add a helper to get LayerBlend secondary input selection. This is
needed by disabling CRTC at boot in an upcoming commit which tries
to get the selection.

Signed-off-by: Liu Ying <victor.liu@nxp.com>
---
drivers/gpu/drm/imx/dc/dc-lb.c | 21 +++++++++++++++++++++
drivers/gpu/drm/imx/dc/dc-pe.h | 1 +
2 files changed, 22 insertions(+)

diff --git a/drivers/gpu/drm/imx/dc/dc-lb.c b/drivers/gpu/drm/imx/dc/dc-lb.c
index 38f966625d382487e45c2e0c202e15c1417f6e65..b0f3fb818799b58597e8ae41d868338c3fd40800 100644
--- a/drivers/gpu/drm/imx/dc/dc-lb.c
+++ b/drivers/gpu/drm/imx/dc/dc-lb.c
@@ -23,6 +23,8 @@
#define PIXENGCFG_DYNAMIC_SEC_SEL_MASK GENMASK(13, 8)
#define PIXENGCFG_DYNAMIC_SEC_SEL(x) \
FIELD_PREP(PIXENGCFG_DYNAMIC_SEC_SEL_MASK, (x))
+#define PIXENGCFG_DYNAMIC_SEC_SEL_GET(x) \
+ FIELD_GET(PIXENGCFG_DYNAMIC_SEC_SEL_MASK, (x))

#define STATICCONTROL 0x8
#define SHDTOKSEL_MASK GENMASK(4, 3)
@@ -182,6 +184,25 @@ void dc_lb_pec_dynamic_sec_sel(struct dc_lb *lb, enum dc_link_id sec)
dev_warn(lb->dev, "invalid secondary input selection:%d\n", sec);
}

+int dc_lb_pec_dynamic_sec_sel_get(struct dc_lb *lb, enum dc_link_id *sec)
+{
+ u32 val;
+
+ regmap_read(lb->reg_pec, PIXENGCFG_DYNAMIC, &val);
+ val = PIXENGCFG_DYNAMIC_SEC_SEL_GET(val);
+
+ switch (val) {
+ case LINK_ID_NONE:
+ case LINK_ID_FETCHWARP2:
+ case LINK_ID_FETCHLAYER0:
+ *sec = val;
+ dev_dbg(lb->dev, "get secondary input selection: 0x%02x\n", val);
+ return 0;
+ default:
+ return -EINVAL;
+ }
+}
+
void dc_lb_pec_clken(struct dc_lb *lb, enum dc_pec_clken clken)
{
regmap_write_bits(lb->reg_pec, PIXENGCFG_DYNAMIC, CLKEN_MASK,
diff --git a/drivers/gpu/drm/imx/dc/dc-pe.h b/drivers/gpu/drm/imx/dc/dc-pe.h
index 0b81dc6b251c452e7ca72f1cd12af065bafaa198..4e38aead69bce6e9ad4cf2a7cd1fedbaeda60650 100644
--- a/drivers/gpu/drm/imx/dc/dc-pe.h
+++ b/drivers/gpu/drm/imx/dc/dc-pe.h
@@ -93,6 +93,7 @@ void dc_ed_init(struct dc_ed *ed);
enum dc_link_id dc_lb_get_link_id(struct dc_lb *lb);
void dc_lb_pec_dynamic_prim_sel(struct dc_lb *lb, enum dc_link_id prim);
void dc_lb_pec_dynamic_sec_sel(struct dc_lb *lb, enum dc_link_id sec);
+int dc_lb_pec_dynamic_sec_sel_get(struct dc_lb *lb, enum dc_link_id *sec);
void dc_lb_pec_clken(struct dc_lb *lb, enum dc_pec_clken clken);
void dc_lb_mode(struct dc_lb *lb, enum dc_lb_mode mode);
void dc_lb_position(struct dc_lb *lb, int x, int y);

--
2.34.1