[PATCH v10 1/3] drm/display: Add drm helper to check pr optimization support

Animesh Manna
2026-03-30T14:06:39Z

Add api to check panel replay optimization supported or not to
drm-core DP tunneling framework which can be used by other driver
as well.

v2: Split generic drm changes from Intel specific changes. [Jouni]

Reviewed-by: Jouni Högander <jouni.hogander@intel.com>
Suggested-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
---
drivers/gpu/drm/display/drm_dp_tunnel.c | 17 +++++++++++++++++
include/drm/display/drm_dp_tunnel.h | 6 ++++++
2 files changed, 23 insertions(+)

diff --git a/drivers/gpu/drm/display/drm_dp_tunnel.c b/drivers/gpu/drm/display/drm_dp_tunnel.c
index 6519b4244728..08dc5d26b2c5 100644
--- a/drivers/gpu/drm/display/drm_dp_tunnel.c
+++ b/drivers/gpu/drm/display/drm_dp_tunnel.c
@@ -149,6 +149,7 @@ struct drm_dp_tunnel {
bool bw_alloc_enabled:1;
bool has_io_error:1;
bool destroyed:1;
+ bool pr_optimization_support:1;
};

struct drm_dp_tunnel_group_state;
@@ -508,6 +509,8 @@ create_tunnel(struct drm_dp_tunnel_mgr *mgr,

tunnel->bw_alloc_supported = tunnel_reg_bw_alloc_supported(regs);
tunnel->bw_alloc_enabled = tunnel_reg_bw_alloc_enabled(regs);
+ tunnel->pr_optimization_support = tunnel_reg(regs, DP_TUNNELING_CAPABILITIES) &
+ DP_PANEL_REPLAY_OPTIMIZATION_SUPPORT;

if (!add_tunnel_to_group(mgr, drv_group_id, tunnel)) {
kfree(tunnel);
@@ -1036,6 +1039,20 @@ bool drm_dp_tunnel_bw_alloc_is_enabled(const struct drm_dp_tunnel *tunnel)
}
EXPORT_SYMBOL(drm_dp_tunnel_bw_alloc_is_enabled);

+/**
+ * drm_dp_tunnel_pr_optimization_supported - Query the PR BW optimization support
+ * @tunnel: Tunnel object
+ *
+ * Query if the PR BW optimization is supported for @tunnel.
+ *
+ * Returns %true if the PR BW optimiation is supported for @tunnel.
+ */
+bool drm_dp_tunnel_pr_optimization_supported(const struct drm_dp_tunnel *tunnel)
+{
+ return tunnel && tunnel->pr_optimization_support;
+}
+EXPORT_SYMBOL(drm_dp_tunnel_pr_optimization_supported);
+
static int clear_bw_req_state(struct drm_dp_aux *aux)
{
u8 bw_req_mask = DP_BW_REQUEST_SUCCEEDED | DP_BW_REQUEST_FAILED;
diff --git a/include/drm/display/drm_dp_tunnel.h b/include/drm/display/drm_dp_tunnel.h
index 87212c847915..4aa3ce9fd829 100644
--- a/include/drm/display/drm_dp_tunnel.h
+++ b/include/drm/display/drm_dp_tunnel.h
@@ -53,6 +53,7 @@ int drm_dp_tunnel_destroy(struct drm_dp_tunnel *tunnel);
int drm_dp_tunnel_enable_bw_alloc(struct drm_dp_tunnel *tunnel);
int drm_dp_tunnel_disable_bw_alloc(struct drm_dp_tunnel *tunnel);
bool drm_dp_tunnel_bw_alloc_is_enabled(const struct drm_dp_tunnel *tunnel);
+bool drm_dp_tunnel_pr_optimization_supported(const struct drm_dp_tunnel *tunnel);
int drm_dp_tunnel_alloc_bw(struct drm_dp_tunnel *tunnel, int bw);
int drm_dp_tunnel_get_allocated_bw(struct drm_dp_tunnel *tunnel);
int drm_dp_tunnel_update_state(struct drm_dp_tunnel *tunnel);
@@ -140,6 +141,11 @@ static inline bool drm_dp_tunnel_bw_alloc_is_enabled(const struct drm_dp_tunnel
return false;
}

+static inline bool drm_dp_tunnel_pr_optimization_supported(const struct drm_dp_tunnel *tunnel)
+{
+ return false;
+}
+
static inline int
drm_dp_tunnel_alloc_bw(struct drm_dp_tunnel *tunnel, int bw)
{
--
2.29.0