Add support to enable the DP tunnel BW allocation mode. Follow-up
patches will call the required helpers added here to prepare for a
modeset on a link with DP tunnels, the last change in the patchset
actually enabling BWA.
With BWA enabled, the driver will expose the full mode list a display
supports, regardless of any BW limitation on a shared (Thunderbolt)
link. Such BW limits will be checked against only during a modeset, when
the driver has the full knowledge of each display's BW requirement.
If the link BW changes in a way that a connector's modelist may also
change, userspace will get a hotplug notification for all the connectors
sharing the same link (so it can adjust the mode used for a display).
The BW limitation can change at any point, asynchronously to modesets
on a given connector, so a modeset can fail even though the atomic check
for it passed. In such scenarios userspace will get a bad link
notification and in response is supposed to retry the modeset.
v2:
- Fix old vs. new connector state in intel_dp_tunnel_atomic_check_state().
(Ville)
- Fix propagating the error from
intel_dp_tunnel_atomic_compute_stream_bw(). (Ville)
- Move tunnel==NULL checks from driver to DRM core helpers. (Ville)
- Simplify return flow from intel_dp_tunnel_detect(). (Ville)
- s/dp_tunnel_state/inherited_dp_tunnels (Ville)
- Simplify struct intel_dp_tunnel_inherited_state. (Ville)
- Unconstify object pointers (vs. states) where possible. (Ville)
- Init crtc_state while declaring it in check_group_state(). (Ville)
- Join obj->base.id, obj->name arg lines in debug prints to reduce LOC.
(Ville)
- Add/rework intel_dp_tunnel_atomic_alloc_bw() to prepare for moving the
BW allocation from encoder hooks up to intel_atomic_commit_tail()
later in the patchset.
- Disable BW alloc mode during system suspend.
- Allocate the required BW for all tunnels during system resume.
- Add intel_dp_tunnel_atomic_clear_stream_bw() instead of the open-coded
sequence in a follow-up patch.
- Add function documentation to all exported functions.
- Add CONFIG_USB4 dependency to CONFIG_DRM_I915_DP_TUNNEL.
Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
Signed-off-by: Imre Deak <imre.deak@xxxxxxxxx>
---
drivers/gpu/drm/i915/Kconfig | 14 +
drivers/gpu/drm/i915/Kconfig.debug | 1 +
drivers/gpu/drm/i915/Makefile | 3 +
drivers/gpu/drm/i915/display/intel_atomic.c | 2 +
drivers/gpu/drm/i915/display/intel_crtc.c | 25 +
drivers/gpu/drm/i915/display/intel_crtc.h | 1 +
.../gpu/drm/i915/display/intel_display_core.h | 1 +
.../drm/i915/display/intel_display_types.h | 9 +
.../gpu/drm/i915/display/intel_dp_tunnel.c | 815 ++++++++++++++++++
.../gpu/drm/i915/display/intel_dp_tunnel.h | 133 +++
10 files changed, 1004 insertions(+)
create mode 100644 drivers/gpu/drm/i915/display/intel_dp_tunnel.c
create mode 100644 drivers/gpu/drm/i915/display/intel_dp_tunnel.h
diff --git a/drivers/gpu/drm/i915/Kconfig b/drivers/gpu/drm/i915/Kconfig
index 3089029abba48..5932024f8f954 100644
--- a/drivers/gpu/drm/i915/Kconfig
+++ b/drivers/gpu/drm/i915/Kconfig
@@ -155,6 +155,20 @@ config DRM_I915_PXP
protected session and manage the status of the alive software session,
as well as its life cycle.
+config DRM_I915_DP_TUNNEL
+ bool "Enable DP tunnel support"
+ depends on DRM_I915
+ depends on USB4
+ select DRM_DISPLAY_DP_TUNNEL
+ default y
+ help
+ Choose this option to detect DP tunnels and enable the Bandwidth
+ Allocation mode for such tunnels. This allows using the maximum
+ resolution allowed by the link BW on all displays sharing the
+ link BW, for instance on a Thunderbolt link.
+
+ If in doubt, say "Y".
+
menu "drm/i915 Debugging"
depends on DRM_I915
depends on EXPERT
diff --git a/drivers/gpu/drm/i915/Kconfig.debug b/drivers/gpu/drm/i915/Kconfig.debug
index 5b7162076850c..bc18e2d9ea05d 100644
--- a/drivers/gpu/drm/i915/Kconfig.debug
+++ b/drivers/gpu/drm/i915/Kconfig.debug
@@ -28,6 +28,7 @@ config DRM_I915_DEBUG
select STACKDEPOT
select STACKTRACE
select DRM_DP_AUX_CHARDEV
+ select DRM_DISPLAY_DEBUG_DP_TUNNEL_STATE if DRM_I915_DP_TUNNEL
select X86_MSR # used by igt/pm_rpm
select DRM_VGEM # used by igt/prime_vgem (dmabuf interop checks)
select DRM_DEBUG_MM if DRM=y
diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
index c13f14edb5088..3ef6ed41e62b4 100644
--- a/drivers/gpu/drm/i915/Makefile
+++ b/drivers/gpu/drm/i915/Makefile
@@ -369,6 +369,9 @@ i915-y += \
display/vlv_dsi.o \
display/vlv_dsi_pll.o
+i915-$(CONFIG_DRM_I915_DP_TUNNEL) += \
+ display/intel_dp_tunnel.o
+
i915-y += \
i915_perf.o
diff --git a/drivers/gpu/drm/i915/display/intel_atomic.c b/drivers/gpu/drm/i915/display/intel_atomic.c
index ec0d5168b5035..96ab37e158995 100644
--- a/drivers/gpu/drm/i915/display/intel_atomic.c
+++ b/drivers/gpu/drm/i915/display/intel_atomic.c
@@ -29,6 +29,7 @@
* See intel_atomic_plane.c for the plane-specific atomic functionality.
*/
+#include <drm/display/drm_dp_tunnel.h>
#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_fourcc.h>
@@ -38,6 +39,7 @@
#include "intel_atomic.h"
#include "intel_cdclk.h"
#include "intel_display_types.h"
+#include "intel_dp_tunnel.h"
#include "intel_global_state.h"
#include "intel_hdcp.h"
#include "intel_psr.h"
diff --git a/drivers/gpu/drm/i915/display/intel_crtc.c b/drivers/gpu/drm/i915/display/intel_crtc.c
index 17ed2e62cc66a..8224400b5b72c 100644
--- a/drivers/gpu/drm/i915/display/intel_crtc.c
+++ b/drivers/gpu/drm/i915/display/intel_crtc.c
@@ -681,3 +681,28 @@ u32 intel_crtc_try_sync_pipes(struct drm_i915_private *i915, u32 pipe_mask)
return synced;
}
+
+/**
+ * intel_crtc_sync_pipes - Sync pending commits on a set of pipes
+ * @i915: i915 device object
+ * @pipe_mask: Mask of pipes to sync
+ *
+ * Sync a pending non-blocking commit for the provided pipes in
+ * @pipe_mask.
+ */
+void intel_crtc_sync_pipes(struct drm_i915_private *i915, u32 pipe_mask)
+{
+ struct intel_crtc *crtc;
+
+ for_each_intel_crtc_in_pipe_mask(&i915->drm, crtc, pipe_mask) {
+ const struct intel_crtc_state *crtc_state =
+ to_intel_crtc_state(crtc->base.state);
+ bool synced = true;
+
+ if (crtc_state->uapi.commit)
+ synced = wait_for_completion_timeout(&crtc_state->uapi.commit->hw_done,
+ msecs_to_jiffies(5000));
+
+ drm_WARN_ON(&i915->drm, !synced);
+ }
+}
diff --git a/drivers/gpu/drm/i915/display/intel_crtc.h b/drivers/gpu/drm/i915/display/intel_crtc.h
index 71a5b93166da7..ffee73b8df74e 100644
--- a/drivers/gpu/drm/i915/display/intel_crtc.h
+++ b/drivers/gpu/drm/i915/display/intel_crtc.h
@@ -48,5 +48,6 @@ void intel_wait_for_vblank_if_active(struct drm_i915_private *i915,
enum pipe pipe);
void intel_crtc_wait_for_next_vblank(struct intel_crtc *crtc);
u32 intel_crtc_try_sync_pipes(struct drm_i915_private *i915, u32 pipe_mask);
+void intel_crtc_sync_pipes(struct drm_i915_private *i915, u32 pipe_mask);
#endif
diff --git a/drivers/gpu/drm/i915/display/intel_display_core.h b/drivers/gpu/drm/i915/display/intel_display_core.h
index fdeaac994e17b..2167dbee5eea7 100644
--- a/drivers/gpu/drm/i915/display/intel_display_core.h
+++ b/drivers/gpu/drm/i915/display/intel_display_core.h
@@ -524,6 +524,7 @@ struct intel_display {
} wq;
/* Grouping using named structs. Keep sorted. */
+ struct drm_dp_tunnel_mgr *dp_tunnel_mgr;
struct intel_audio audio;
struct intel_dpll dpll;
struct intel_fbc *fbc[I915_MAX_FBCS];
diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
index 578763e202c01..601e7f88e6c61 100644
--- a/drivers/gpu/drm/i915/display/intel_display_types.h
+++ b/drivers/gpu/drm/i915/display/intel_display_types.h
@@ -33,6 +33,7 @@
#include <drm/display/drm_dp_dual_mode_helper.h>
#include <drm/display/drm_dp_mst_helper.h>
+#include <drm/display/drm_dp_tunnel.h>
#include <drm/display/drm_dsc.h>
#include <drm/drm_atomic.h>
#include <drm/drm_crtc.h>
@@ -678,6 +679,8 @@ struct intel_atomic_state {
struct intel_shared_dpll_state shared_dpll[I915_NUM_PLLS];
+ struct intel_dp_tunnel_inherited_state *inherited_dp_tunnels;
+
/*
* Current watermarks can't be trusted during hardware readout, so
* don't bother calculating intermediate watermarks.
@@ -1375,6 +1378,9 @@ struct intel_crtc_state {
struct drm_dsc_config config;
} dsc;
+ /* DP tunnel used for BW allocation. */
+ struct drm_dp_tunnel_ref dp_tunnel_ref;
+
/* HSW+ linetime watermarks */
u16 linetime;
u16 ips_linetime;
@@ -1785,6 +1791,9 @@ struct intel_dp {
/* connector directly attached - won't be use for modeset in mst world */
struct intel_connector *attached_connector;
+ struct drm_dp_tunnel *tunnel;
+ bool tunnel_suspended:1;
+
/* mst connector list */
struct intel_dp_mst_encoder *mst_encoders[I915_MAX_PIPES];
struct drm_dp_mst_topology_mgr mst_mgr;
diff --git a/drivers/gpu/drm/i915/display/intel_dp_tunnel.c b/drivers/gpu/drm/i915/display/intel_dp_tunnel.c
new file mode 100644
index 0000000000000..fd639ded853ae
--- /dev/null
+++ b/drivers/gpu/drm/i915/display/intel_dp_tunnel.c
@@ -0,0 +1,815 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2023 Intel Corporation
+ */
+
+#include "i915_drv.h"
+
+#include <drm/display/drm_dp_tunnel.h>
+
+#include "intel_atomic.h"
+#include "intel_crtc.h"
+#include "intel_display_limits.h"
+#include "intel_display_types.h"
+#include "intel_dp.h"
+#include "intel_dp_link_training.h"
+#include "intel_dp_mst.h"
+#include "intel_dp_tunnel.h"
+#include "intel_link_bw.h"
+
+struct intel_dp_tunnel_inherited_state {
+ struct drm_dp_tunnel_ref ref[I915_MAX_PIPES];
+};
+
+/**
+ * intel_dp_tunnel_disconnect - Disconnect a DP tunnel from a port
+ * @intel_dp: DP port object the tunnel is connected to
+ *
+ * Disconnect a DP tunnel from @intel_dp, destroying any related state. This
+ * should be called after detecting a sink-disconnect event from the port.
+ */
+void intel_dp_tunnel_disconnect(struct intel_dp *intel_dp)
+{
+ drm_dp_tunnel_destroy(intel_dp->tunnel);
+ intel_dp->tunnel = NULL;
+}
+
+/**
+ * intel_dp_tunnel_destroy - Destroy a DP tunnel
+ * @intel_dp: DP port object the tunnel is connected to
+ *
+ * Destroy a DP tunnel connected to @intel_dp, after disabling the BW
+ * allocation mode on the tunnel. This should be called while destroying the
+ * port.
+ */
+void intel_dp_tunnel_destroy(struct intel_dp *intel_dp)
+{
+ if (intel_dp_tunnel_bw_alloc_is_enabled(intel_dp))
+ drm_dp_tunnel_disable_bw_alloc(intel_dp->tunnel);
+
+ intel_dp_tunnel_disconnect(intel_dp);
+}
+
+static int kbytes_to_mbits(int kbytes)
+{
+ return DIV_ROUND_UP(kbytes * 8, 1000);
+}
+
+static int get_current_link_bw(struct intel_dp *intel_dp,
+ bool *below_dprx_bw)
+{
+ int rate = intel_dp_max_common_rate(intel_dp);
+ int lane_count = intel_dp_max_common_lane_count(intel_dp);
+ int bw;
+
+ bw = intel_dp_max_link_data_rate(intel_dp, rate, lane_count);
+ *below_dprx_bw = bw < drm_dp_max_dprx_data_rate(rate, lane_count);
+
+ return bw;
+}
+
+static int update_tunnel_state(struct intel_dp *intel_dp)
+{
+ struct drm_i915_private *i915 = dp_to_i915(intel_dp);
+ struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
+ bool old_bw_below_dprx;
+ bool new_bw_below_dprx;
+ int old_bw;
+ int new_bw;
+ int ret;
+
+ old_bw = get_current_link_bw(intel_dp, &old_bw_below_dprx);
+
+ ret = drm_dp_tunnel_update_state(intel_dp->tunnel);
+ if (ret < 0) {
+ drm_dbg_kms(&i915->drm,
+ "[DPTUN %s][ENCODER:%d:%s] State update failed (err %pe)\n",
+ drm_dp_tunnel_name(intel_dp->tunnel),
+ encoder->base.base.id, encoder->base.name,
+ ERR_PTR(ret));
+
+ return ret;
+ }
+
+ if (ret == 0 ||
+ !drm_dp_tunnel_bw_alloc_is_enabled(intel_dp->tunnel))
+ return 0;
+
+ intel_dp_update_sink_caps(intel_dp);
+
+ new_bw = get_current_link_bw(intel_dp, &new_bw_below_dprx);
+
+ /* Suppress the notification if the mode list can't change due to bw. */
+ if (old_bw_below_dprx == new_bw_below_dprx &&
+ !new_bw_below_dprx)
+ return 0;
+
+ drm_dbg_kms(&i915->drm,
+ "[DPTUN %s][ENCODER:%d:%s] Notify users about BW change: %d -> %d\n",
+ drm_dp_tunnel_name(intel_dp->tunnel),
+ encoder->base.base.id, encoder->base.name,
+ kbytes_to_mbits(old_bw), kbytes_to_mbits(new_bw));
+
+ return 1;
+}
+
+/*
+ * Allocate the BW for a tunnel on a DP connector/port if the connector/port
+ * was already active when detecting the tunnel. The allocated BW must be
+ * freed by the next atomic modeset, storing the BW in the
+ * intel_atomic_state::inherited_dp_tunnels, and calling
+ * intel_dp_tunnel_atomic_free_bw().
+ */
+static int allocate_initial_tunnel_bw_for_pipes(struct intel_dp *intel_dp, u8 pipe_mask)
+{
+ struct drm_i915_private *i915 = dp_to_i915(intel_dp);
+ struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
+ struct intel_crtc *crtc;
+ int tunnel_bw = 0;
+ int err;
+
+ for_each_intel_crtc_in_pipe_mask(&i915->drm, crtc, pipe_mask) {
+ const struct intel_crtc_state *crtc_state =
+ to_intel_crtc_state(crtc->base.state);
+ int stream_bw = intel_dp_config_required_rate(crtc_state);
+
+ tunnel_bw += stream_bw;
+
+ drm_dbg_kms(&i915->drm,
+ "[DPTUN %s][ENCODER:%d:%s][CRTC:%d:%s] Initial BW for stream %d: %d/%d Mb/s\n",
+ drm_dp_tunnel_name(intel_dp->tunnel),
+ encoder->base.base.id, encoder->base.name,
+ crtc->base.base.id, crtc->base.name,
+ crtc->pipe,
+ kbytes_to_mbits(stream_bw), kbytes_to_mbits(tunnel_bw));
+ }
+
+ err = drm_dp_tunnel_alloc_bw(intel_dp->tunnel, tunnel_bw);
+ if (err) {
+ drm_dbg_kms(&i915->drm,
+ "[DPTUN %s][ENCODER:%d:%s] Initial BW allocation failed (err %pe)\n",
+ drm_dp_tunnel_name(intel_dp->tunnel),
+ encoder->base.base.id, encoder->base.name,
+ ERR_PTR(err));
+
+ return err;
+ }
+
+ return update_tunnel_state(intel_dp);
+}
+
+static int allocate_initial_tunnel_bw(struct intel_dp *intel_dp,
+ struct drm_modeset_acquire_ctx *ctx)
+{
+ struct drm_i915_private *i915 = dp_to_i915(intel_dp);
+ u8 pipe_mask;
+ int err;
+
+ err = intel_dp_get_active_pipes(intel_dp, ctx, &pipe_mask);
+ if (err)
+ return err;
+
+ intel_crtc_sync_pipes(i915, pipe_mask);
+
+ return allocate_initial_tunnel_bw_for_pipes(intel_dp, pipe_mask);
+}
+
+static int detect_new_tunnel(struct intel_dp *intel_dp, struct drm_modeset_acquire_ctx *ctx)
+{
+ struct drm_i915_private *i915 = dp_to_i915(intel_dp);
+ struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
+ struct drm_dp_tunnel *tunnel;
+ int ret;
+
+ tunnel = drm_dp_tunnel_detect(i915->display.dp_tunnel_mgr,
+ &intel_dp->aux);
+ if (IS_ERR(tunnel))
+ return PTR_ERR(tunnel);
+
+ intel_dp->tunnel = tunnel;
+
+ ret = drm_dp_tunnel_enable_bw_alloc(intel_dp->tunnel);
+ if (ret) {
+ if (ret == -EOPNOTSUPP)
+ return 0;
+
+ drm_dbg_kms(&i915->drm,
+ "[DPTUN %s][ENCODER:%d:%s] Failed to enable BW allocation mode (ret %pe)\n",
+ drm_dp_tunnel_name(intel_dp->tunnel),
+ encoder->base.base.id, encoder->base.name,
+ ERR_PTR(ret));
+
+ /* Keep the tunnel with BWA disabled */
+ return 0;
+ }
+
+ ret = allocate_initial_tunnel_bw(intel_dp, ctx);
+ if (ret < 0)
+ intel_dp_tunnel_destroy(intel_dp);
+
+ return ret;
+}
+
+/**
+ * intel_dp_tunnel_detect - Detect a DP tunnel on a port
+ * @intel_dp: DP port object
+ * @ctx: lock context acquired by the connector detection handler
+ *
+ * Detect a DP tunnel on the @intel_dp port, enabling the BW allocation mode
+ * on it if supported and allocating the BW required on an already active port.
+ * The BW allocated this way must be freed by the next atomic modeset calling
+ * intel_dp_tunnel_atomic_free_bw().
+ *
+ * If @intel_dp has already a tunnel detected on it, update the tunnel's state
+ * wrt. its support for BW allocation mode and the available BW via the
+ * tunnel. If the tunnel's state change requires this - for instance the
+ * tunnel's group ID has changed - the tunnel will be dropped and recreated.
+ *
+ * Return 0 in case of success - after any tunnel detected and added to
+ * @intel_dp - 1 in case the BW on an already existing tunnel has changed in a
+ * way that requires notifying user space.
+ */
+int intel_dp_tunnel_detect(struct intel_dp *intel_dp, struct drm_modeset_acquire_ctx *ctx)
+{
+ int ret;
+
+ if (intel_dp_is_edp(intel_dp))
+ return 0;
+
+ if (intel_dp->tunnel) {
+ ret = update_tunnel_state(intel_dp);
+ if (ret >= 0)
+ return ret;
+
+ /* Try to recreate the tunnel after an update error. */
+ intel_dp_tunnel_destroy(intel_dp);
+ }
+
+ return detect_new_tunnel(intel_dp, ctx);
+}
+
+/**
+ * intel_dp_tunnel_bw_alloc_is_enabled - Query the BW allocation support on a tunnel
+ * @intel_dp: DP port object
+ *
+ * Query whether a DP tunnel is connected on @intel_dp and the tunnel supports
+ * the BW allocation mode.
+ *
+ * Returns %true if the BW allocation mode is supported on @intel_dp.
+ */
+bool intel_dp_tunnel_bw_alloc_is_enabled(struct intel_dp *intel_dp)
+{
+ return drm_dp_tunnel_bw_alloc_is_enabled(intel_dp->tunnel);
+}
+
+/**
+ * intel_dp_tunnel_suspend - Suspend a DP tunnel connected on a port
+ * @intel_dp: DP port object
+ *
+ * Suspend a DP tunnel on @intel_dp with BW allocation mode enabled on it.
+ */
+void intel_dp_tunnel_suspend(struct intel_dp *intel_dp)
+{
+ struct drm_i915_private *i915 = dp_to_i915(intel_dp);
+ struct intel_connector *connector = intel_dp->attached_connector;
+ struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
+
+ if (!intel_dp_tunnel_bw_alloc_is_enabled(intel_dp))
+ return;
+
+ drm_dbg_kms(&i915->drm, "[DPTUN %s][CONNECTOR:%d:%s][ENCODER:%d:%s] Suspend\n",
+ drm_dp_tunnel_name(intel_dp->tunnel),
+ connector->base.base.id, connector->base.name,
+ encoder->base.base.id, encoder->base.name);
+
+ drm_dp_tunnel_disable_bw_alloc(intel_dp->tunnel);
+
+ intel_dp->tunnel_suspended = true;
+}
+
+/**
+ * intel_dp_tunnel_resume - Resume a DP tunnel connected on a port
+ * @intel_dp: DP port object
+ * @crtc_state: CRTC state
+ * @dpcd_updated: the DPCD DPRX capabilities got updated during resume
+ *
+ * Resume a DP tunnel on @intel_dp with BW allocation mode enabled on it.
+ */
+void intel_dp_tunnel_resume(struct intel_dp *intel_dp,
+ const struct intel_crtc_state *crtc_state,
+ bool dpcd_updated)
+{
+ struct drm_i915_private *i915 = dp_to_i915(intel_dp);
+ struct intel_connector *connector = intel_dp->attached_connector;
+ struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
+ u8 dpcd[DP_RECEIVER_CAP_SIZE];
+ u8 pipe_mask;
+ int err = 0;
+
+ if (!intel_dp->tunnel_suspended)
+ return;
+
+ intel_dp->tunnel_suspended = false;
+
+ drm_dbg_kms(&i915->drm, "[DPTUN %s][CONNECTOR:%d:%s][ENCODER:%d:%s] Resume\n",
+ drm_dp_tunnel_name(intel_dp->tunnel),
+ connector->base.base.id, connector->base.name,
+ encoder->base.base.id, encoder->base.name);
+
+ /*
+ * The TBT Connection Manager requires the GFX driver to read out
+ * the sink's DPRX caps to be able to service any BW requests later.
+ * During resume overriding the caps in @intel_dp cached before
+ * suspend must be avoided, so do here only a dummy read, unless the
+ * capabilities were updated already during resume.
+ */
+ if (!dpcd_updated) {
+ err = intel_dp_read_dprx_caps(intel_dp, dpcd);
+
+ if (err) {
+ drm_dp_tunnel_set_io_error(intel_dp->tunnel);
+ goto out_err;
+ }
+ }
+
+ err = drm_dp_tunnel_enable_bw_alloc(intel_dp->tunnel);
+ if (err)
+ goto out_err;
+
+ pipe_mask = 0;
+ if (crtc_state) {
+ struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
+
+ /* TODO: Add support for MST */
+ pipe_mask |= BIT(crtc->pipe);
+ }
+
+ err = allocate_initial_tunnel_bw_for_pipes(intel_dp, pipe_mask);
+ if (err)
+ goto out_err;
+
+ return;
+
+out_err:
+ drm_dbg_kms(&i915->drm,
+ "[DPTUN %s][CONNECTOR:%d:%s][ENCODER:%d:%s] Tunnel can't be resumed, will drop and redect it (err %pe)\n",
+ drm_dp_tunnel_name(intel_dp->tunnel),
+ connector->base.base.id, connector->base.name,
+ encoder->base.base.id, encoder->base.name,
+ ERR_PTR(err));
+}
+
+static struct drm_dp_tunnel *
+get_inherited_tunnel(struct intel_atomic_state *state, struct intel_crtc *crtc)
+{
+ if (!state->inherited_dp_tunnels)
+ return NULL;
+
+ return state->inherited_dp_tunnels->ref[crtc->pipe].tunnel;
+}
+
+static int
+add_inherited_tunnel(struct intel_atomic_state *state,
+ struct drm_dp_tunnel *tunnel,
+ struct intel_crtc *crtc)
+{
+ struct drm_i915_private *i915 = to_i915(state->base.dev);
+ struct drm_dp_tunnel *old_tunnel;
+
+ old_tunnel = get_inherited_tunnel(state, crtc);
+ if (old_tunnel) {
+ drm_WARN_ON(&i915->drm, old_tunnel != tunnel);
+ return 0;
+ }
+
+ if (!state->inherited_dp_tunnels) {
+ state->inherited_dp_tunnels = kzalloc(sizeof(*state->inherited_dp_tunnels),
+ GFP_KERNEL);
+ if (!state->inherited_dp_tunnels)
+ return -ENOMEM;
+ }
+
+ drm_dp_tunnel_ref_get(tunnel, &state->inherited_dp_tunnels->ref[crtc->pipe]);
+
+ return 0;
+}
+
+static int check_inherited_tunnel_state(struct intel_atomic_state *state,
+ struct intel_dp *intel_dp,
+ const struct intel_digital_connector_state *old_conn_state)
+{
+ struct drm_i915_private *i915 = dp_to_i915(intel_dp);
+ struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
+ struct intel_connector *connector =
+ to_intel_connector(old_conn_state->base.connector);
+ struct intel_crtc *old_crtc;
+ const struct intel_crtc_state *old_crtc_state;
+
+ /*
+ * If a BWA tunnel gets detected only after the corresponding
+ * connector got enabled already without a BWA tunnel, or a different
+ * BWA tunnel (which was removed meanwhile) the old CRTC state won't
+ * contain the state of the current tunnel. This tunnel still has a
+ * reserved BW, which needs to be released, add the state for such
+ * inherited tunnels separately only to this atomic state.
+ */
+ if (!intel_dp_tunnel_bw_alloc_is_enabled(intel_dp))
+ return 0;
+
+ if (!old_conn_state->base.crtc)
+ return 0;
+
+ old_crtc = to_intel_crtc(old_conn_state->base.crtc);
+ old_crtc_state = intel_atomic_get_old_crtc_state(state, old_crtc);
+
+ if (!old_crtc_state->hw.active ||
+ old_crtc_state->dp_tunnel_ref.tunnel == intel_dp->tunnel)
+ return 0;
+
+ drm_dbg_kms(&i915->drm,
+ "[DPTUN %s][CONNECTOR:%d:%s][ENCODER:%d:%s][CRTC:%d:%s] Adding state for inherited tunnel %p\n",
+ drm_dp_tunnel_name(intel_dp->tunnel),
+ connector->base.base.id, connector->base.name,
+ encoder->base.base.id, encoder->base.name,
+ old_crtc->base.base.id, old_crtc->base.name,
+ intel_dp->tunnel);
+
+ return add_inherited_tunnel(state, intel_dp->tunnel, old_crtc);
+}
+
+/**
+ * intel_dp_tunnel_atomic_cleanup_inherited_state - Free any inherited DP tunnel state
+ * @state: Atomic state
+ *
+ * Free the inherited DP tunnel state in @state.
+ */
+void intel_dp_tunnel_atomic_cleanup_inherited_state(struct intel_atomic_state *state)
+{
+ enum pipe pipe;
+
+ if (!state->inherited_dp_tunnels)
+ return;
+
+ for_each_pipe(to_i915(state->base.dev), pipe)
+ if (state->inherited_dp_tunnels->ref[pipe].tunnel)
+ drm_dp_tunnel_ref_put(&state->inherited_dp_tunnels->ref[pipe]);
+
+ kfree(state->inherited_dp_tunnels);
+ state->inherited_dp_tunnels = NULL;
+}
+
+static int intel_dp_tunnel_atomic_add_group_state(struct intel_atomic_state *state,
+ struct drm_dp_tunnel *tunnel)
+{
+ struct drm_i915_private *i915 = to_i915(state->base.dev);
+ u32 pipe_mask;
+ int err;
+
+ err = drm_dp_tunnel_atomic_get_group_streams_in_state(&state->base,
+ tunnel, &pipe_mask);
+ if (err)
+ return err;
+
+ drm_WARN_ON(&i915->drm, pipe_mask & ~((1 << I915_MAX_PIPES) - 1));
+
+ return intel_modeset_pipes_in_mask_early(state, "DPTUN", pipe_mask);
+}
+
+/**
+ * intel_dp_tunnel_atomic_add_state_for_crtc - Add CRTC specific DP tunnel state
+ * @state: Atomic state
+ * @crtc: CRTC to add the tunnel state for
+ *
+ * Add the DP tunnel state for @crtc if the CRTC (aka DP tunnel stream) is enabled
+ * via a DP tunnel.
+ *
+ * Return 0 in case of success, a negative error code otherwise.
+ */
+int intel_dp_tunnel_atomic_add_state_for_crtc(struct intel_atomic_state *state,
+ struct intel_crtc *crtc)
+{
+ const struct intel_crtc_state *new_crtc_state =
+ intel_atomic_get_new_crtc_state(state, crtc);
+ const struct drm_dp_tunnel_state *tunnel_state;
+ struct drm_dp_tunnel *tunnel = new_crtc_state->dp_tunnel_ref.tunnel;
+
+ if (!tunnel)
+ return 0;
+
+ tunnel_state = drm_dp_tunnel_atomic_get_state(&state->base, tunnel);
+ if (IS_ERR(tunnel_state))
+ return PTR_ERR(tunnel_state);
+
+ return 0;
+}
+
+static int check_group_state(struct intel_atomic_state *state,
+ struct intel_dp *intel_dp,
+ struct intel_connector *connector,
+ struct intel_crtc *crtc)
+{
+ struct drm_i915_private *i915 = to_i915(state->base.dev);
+ struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
+ const struct intel_crtc_state *crtc_state =
+ intel_atomic_get_new_crtc_state(state, crtc);
+
+ if (!crtc_state->dp_tunnel_ref.tunnel)
+ return 0;
+
+ drm_dbg_kms(&i915->drm,
+ "[DPTUN %s][CONNECTOR:%d:%s][ENCODER:%d:%s][CRTC:%d:%s] Adding group state for tunnel %p\n",
+ drm_dp_tunnel_name(intel_dp->tunnel),
+ connector->base.base.id, connector->base.name,
+ encoder->base.base.id, encoder->base.name,
+ crtc->base.base.id, crtc->base.name,
+ crtc_state->dp_tunnel_ref.tunnel);
+
+ return intel_dp_tunnel_atomic_add_group_state(state, crtc_state->dp_tunnel_ref.tunnel);
+}
+
+/**
+ * intel_dp_tunnel_atomic_check_state - Check a connector's DP tunnel specific state
+ * @state: Atomic state
+ * @intel_dp: DP port object
+ * @connector: connector using @intel_dp
+ *
+ * Check and add the DP tunnel atomic state for @intel_dp/@connector to
+ * @state, if there is a DP tunnel detected on @intel_dp with BW allocation
+ * mode enabled on it, or if @intel_dp/@connector was previously enabled via a
+ * DP tunnel.
+ *
+ * Returns 0 in case of success, or a negative error code otherwise.
+ */
+int intel_dp_tunnel_atomic_check_state(struct intel_atomic_state *state,
+ struct intel_dp *intel_dp,
+ struct intel_connector *connector)
+{
+ const struct intel_digital_connector_state *old_conn_state =
+ intel_atomic_get_old_connector_state(state, connector);
+ const struct intel_digital_connector_state *new_conn_state =
+ intel_atomic_get_new_connector_state(state, connector);
+ int err;
+
+ if (old_conn_state->base.crtc) {
+ err = check_group_state(state, intel_dp, connector,
+ to_intel_crtc(old_conn_state->base.crtc));
+ if (err)
+ return err;
+ }
+
+ if (new_conn_state->base.crtc &&
+ new_conn_state->base.crtc != old_conn_state->base.crtc) {
+ err = check_group_state(state, intel_dp, connector,
+ to_intel_crtc(new_conn_state->base.crtc));
+ if (err)
+ return err;
+ }
+
+ return check_inherited_tunnel_state(state, intel_dp, old_conn_state);
+}
+
+/**
+ * intel_dp_tunnel_atomic_compute_stream_bw - Compute the BW required by a DP tunnel stream
+ * @state: Atomic state
+ * @intel_dp: DP object
+ * @connector: connector using @intel_dp
+ * @crtc_state: state of CRTC of the given DP tunnel stream
+ *
+ * Compute the required BW of CRTC (aka DP tunnel stream), storing this BW to
+ * the DP tunnel state containing the stream in @state. Before re-calculating a
+ * BW requirement in the crtc_state state the old BW requirement computed by this
+ * function must be cleared by calling intel_dp_tunnel_atomic_clear_stream_bw().
+ *
+ * Returns 0 in case of success, a negative error code otherwise.
+ */
+int intel_dp_tunnel_atomic_compute_stream_bw(struct intel_atomic_state *state,
+ struct intel_dp *intel_dp,
+ const struct intel_connector *connector,
+ struct intel_crtc_state *crtc_state)
+{
+ struct drm_i915_private *i915 = to_i915(state->base.dev);
+ struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
+ struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
+ int required_rate = intel_dp_config_required_rate(crtc_state);
+ int ret;
+
+ if (!intel_dp_tunnel_bw_alloc_is_enabled(intel_dp))
+ return 0;
+
+ drm_dbg_kms(&i915->drm,
+ "[DPTUN %s][CONNECTOR:%d:%s][ENCODER:%d:%s][CRTC:%d:%s] Stream %d required BW %d Mb/s\n",
+ drm_dp_tunnel_name(intel_dp->tunnel),
+ connector->base.base.id, connector->base.name,
+ encoder->base.base.id, encoder->base.name,
+ crtc->base.base.id, crtc->base.name,
+ crtc->pipe,
+ kbytes_to_mbits(required_rate));
+
+ ret = drm_dp_tunnel_atomic_set_stream_bw(&state->base, intel_dp->tunnel,
+ crtc->pipe, required_rate);
+ if (ret < 0)
+ return ret;
+
+ drm_dp_tunnel_ref_get(intel_dp->tunnel,
+ &crtc_state->dp_tunnel_ref);
+
+ return 0;
+}
+
+/**
+ * intel_dp_tunnel_atomic_clear_stream_bw - Clear any DP tunnel stream BW requirement
+ * @state: Atomic state
+ * @crtc_state: state of CRTC of the given DP tunnel stream
+ *
+ * Clear any DP tunnel stream BW requirement set by
+ * intel_dp_tunnel_atomic_compute_stream_bw().
+ */
+void intel_dp_tunnel_atomic_clear_stream_bw(struct intel_atomic_state *state,
+ struct intel_crtc_state *crtc_state)
+{
+ struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
+
+ if (!crtc_state->dp_tunnel_ref.tunnel)
+ return;
+
+ drm_dp_tunnel_atomic_set_stream_bw(&state->base,
+ crtc_state->dp_tunnel_ref.tunnel,
+ crtc->pipe, 0);
+ drm_dp_tunnel_ref_put(&crtc_state->dp_tunnel_ref);
+}
+
+/**
+ * intel_dp_tunnel_atomic_check_link - Check the DP tunnel atomic state
+ * @state: intel atomic state
+ * @limits: link BW limits
+ *
+ * Check the link configuration for all DP tunnels in @state. If the
+ * configuration is invalid @limits will be updated if possible to
+ * reduce the total BW, after which the configuration for all CRTCs in
+ * @state must be recomputed with the updated @limits.
+ *
+ * Returns:
+ * - 0 if the confugration is valid
+ * - %-EAGAIN, if the configuration is invalid and @limits got updated
+ * with fallback values with which the configuration of all CRTCs in
+ * @state must be recomputed
+ * - Other negative error, if the configuration is invalid without a
+ * fallback possibility, or the check failed for another reason
+ */
+int intel_dp_tunnel_atomic_check_link(struct intel_atomic_state *state,
+ struct intel_link_bw_limits *limits)
+{
+ u32 failed_stream_mask;
+ int err;
+
+ err = drm_dp_tunnel_atomic_check_stream_bws(&state->base,
+ &failed_stream_mask);
+ if (err != -ENOSPC)
+ return err;
+
+ err = intel_link_bw_reduce_bpp(state, limits,
+ failed_stream_mask, "DP tunnel link BW");
+
+ return err ? : -EAGAIN;
+}
+
+static void atomic_decrease_bw(struct intel_atomic_state *state)
+{
+ struct intel_crtc *crtc;
+ const struct intel_crtc_state *old_crtc_state;
+ const struct intel_crtc_state *new_crtc_state;
+ int i;
+
+ for_each_oldnew_intel_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) {
+ const struct drm_dp_tunnel_state *new_tunnel_state;
+ struct drm_dp_tunnel *tunnel;
+ int old_bw;
+ int new_bw;
+
+ if (!intel_crtc_needs_modeset(new_crtc_state))
+ continue;
+
+ tunnel = get_inherited_tunnel(state, crtc);
+ if (!tunnel)
+ tunnel = old_crtc_state->dp_tunnel_ref.tunnel;
+
+ if (!tunnel)
+ continue;
+
+ old_bw = drm_dp_tunnel_get_allocated_bw(tunnel);
+
+ new_tunnel_state = drm_dp_tunnel_atomic_get_new_state(&state->base, tunnel);
+ new_bw = drm_dp_tunnel_atomic_get_required_bw(new_tunnel_state);
+
+ if (new_bw >= old_bw)
+ continue;
+
+ drm_dp_tunnel_alloc_bw(tunnel, new_bw);
+ }
+}
+
+static void queue_retry_work(struct intel_atomic_state *state,
+ struct drm_dp_tunnel *tunnel,
+ const struct intel_crtc_state *crtc_state)
+{
+ struct drm_i915_private *i915 = to_i915(state->base.dev);
+ struct intel_encoder *encoder;
+
+ encoder = intel_get_crtc_new_encoder(state, crtc_state);
+
+ if (!intel_digital_port_connected(encoder))
+ return;
+
+ drm_dbg_kms(&i915->drm,
+ "[DPTUN %s][ENCODER:%d:%s] BW allocation failed on a connected sink\n",
+ drm_dp_tunnel_name(tunnel),
+ encoder->base.base.id,
+ encoder->base.name);
+
+ intel_dp_queue_modeset_retry_for_link(state, encoder, crtc_state);
+}
+
+static void atomic_increase_bw(struct intel_atomic_state *state)
+{
+ struct intel_crtc *crtc;
+ const struct intel_crtc_state *crtc_state;
+ int i;
+
+ for_each_new_intel_crtc_in_state(state, crtc, crtc_state, i) {
+ struct drm_dp_tunnel_state *tunnel_state;
+ struct drm_dp_tunnel *tunnel = crtc_state->dp_tunnel_ref.tunnel;
+ int bw;
+
+ if (!intel_crtc_needs_modeset(crtc_state))
+ continue;
+
+ if (!tunnel)
+ continue;
+
+ tunnel_state = drm_dp_tunnel_atomic_get_new_state(&state->base, tunnel);
+
+ bw = drm_dp_tunnel_atomic_get_required_bw(tunnel_state);
+
+ if (drm_dp_tunnel_alloc_bw(tunnel, bw) != 0)
+ queue_retry_work(state, tunnel, crtc_state);
+ }
+}
+
+/**
+ * intel_dp_tunnel_atomic_alloc_bw - Allocate the BW for all modeset tunnels
+ * @state: Atomic state
+ *
+ * Allocate the required BW for all tunnels in @state.
+ */
+void intel_dp_tunnel_atomic_alloc_bw(struct intel_atomic_state *state)
+{
+ atomic_decrease_bw(state);
+ atomic_increase_bw(state);
+}
+
+/**
+ * intel_dp_tunnel_mgr_init - Initialize the DP tunnel manager
+ * @i915: i915 device object
+ *
+ * Initialize the DP tunnel manager. The tunnel manager will support the
+ * detection/management of DP tunnels on all DP connectors, so the function
+ * must be called after all these connectors have been registered already.
+ *
+ * Return 0 in case of success, a negative error code otherwise.
+ */
+int intel_dp_tunnel_mgr_init(struct drm_i915_private *i915)
+{
+ struct drm_dp_tunnel_mgr *tunnel_mgr;
+ struct drm_connector_list_iter connector_list_iter;
+ struct intel_connector *connector;
+ int dp_connectors = 0;
+
+ drm_connector_list_iter_begin(&i915->drm, &connector_list_iter);
+ for_each_intel_connector_iter(connector, &connector_list_iter) {
+ if (connector->base.connector_type != DRM_MODE_CONNECTOR_DisplayPort)
+ continue;
+
+ dp_connectors++;
+ }
+ drm_connector_list_iter_end(&connector_list_iter);
+
+ tunnel_mgr = drm_dp_tunnel_mgr_create(&i915->drm, dp_connectors);
+ if (IS_ERR(tunnel_mgr))
+ return PTR_ERR(tunnel_mgr);
+
+ i915->display.dp_tunnel_mgr = tunnel_mgr;
+
+ return 0;
+}
+
+/**
+ * intel_dp_tunnel_mgr_cleanup - Clean up the DP tunnel manager state
+ * @i915: i915 device object
+ *
+ * Clean up the DP tunnel manager state.
+ */
+void intel_dp_tunnel_mgr_cleanup(struct drm_i915_private *i915)
+{
+ drm_dp_tunnel_mgr_destroy(i915->display.dp_tunnel_mgr);
+ i915->display.dp_tunnel_mgr = NULL;
+}
diff --git a/drivers/gpu/drm/i915/display/intel_dp_tunnel.h b/drivers/gpu/drm/i915/display/intel_dp_tunnel.h
new file mode 100644
index 0000000000000..08b2cba84af2b
--- /dev/null
+++ b/drivers/gpu/drm/i915/display/intel_dp_tunnel.h
@@ -0,0 +1,133 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2023 Intel Corporation
+ */
+
+#ifndef __INTEL_DP_TUNNEL_H__
+#define __INTEL_DP_TUNNEL_H__
+
+#include <linux/errno.h>
+#include <linux/types.h>
+
+struct drm_i915_private;
+struct drm_connector_state;
+struct drm_modeset_acquire_ctx;
+
+struct intel_atomic_state;
+struct intel_connector;
+struct intel_crtc;
+struct intel_crtc_state;
+struct intel_dp;
+struct intel_encoder;
+struct intel_link_bw_limits;
+
+#if defined(CONFIG_DRM_I915_DP_TUNNEL) && defined(I915)
+
+int intel_dp_tunnel_detect(struct intel_dp *intel_dp, struct drm_modeset_acquire_ctx *ctx);
+void intel_dp_tunnel_disconnect(struct intel_dp *intel_dp);
+void intel_dp_tunnel_destroy(struct intel_dp *intel_dp);
+void intel_dp_tunnel_resume(struct intel_dp *intel_dp,
+ const struct intel_crtc_state *crtc_state,
+ bool dpcd_updated);
+void intel_dp_tunnel_suspend(struct intel_dp *intel_dp);
+
+bool intel_dp_tunnel_bw_alloc_is_enabled(struct intel_dp *intel_dp);
+
+void
+intel_dp_tunnel_atomic_cleanup_inherited_state(struct intel_atomic_state *state);
+
+int intel_dp_tunnel_atomic_compute_stream_bw(struct intel_atomic_state *state,
+ struct intel_dp *intel_dp,
+ const struct intel_connector *connector,
+ struct intel_crtc_state *crtc_state);
+void intel_dp_tunnel_atomic_clear_stream_bw(struct intel_atomic_state *state,
+ struct intel_crtc_state *crtc_state);
+
+int intel_dp_tunnel_atomic_add_state_for_crtc(struct intel_atomic_state *state,
+ struct intel_crtc *crtc);
+int intel_dp_tunnel_atomic_check_link(struct intel_atomic_state *state,
+ struct intel_link_bw_limits *limits);
+int intel_dp_tunnel_atomic_check_state(struct intel_atomic_state *state,
+ struct intel_dp *intel_dp,
+ struct intel_connector *connector);
+
+void intel_dp_tunnel_atomic_alloc_bw(struct intel_atomic_state *state);
+
+int intel_dp_tunnel_mgr_init(struct drm_i915_private *i915);
+void intel_dp_tunnel_mgr_cleanup(struct drm_i915_private *i915);
+
+#else
+
+static inline int
+intel_dp_tunnel_detect(struct intel_dp *intel_dp, struct drm_modeset_acquire_ctx *ctx)
+{
+ return -EOPNOTSUPP;
+}
+
+static inline void intel_dp_tunnel_disconnect(struct intel_dp *intel_dp) {}
+static inline void intel_dp_tunnel_destroy(struct intel_dp *intel_dp) {}
+static inline void intel_dp_tunnel_resume(struct intel_dp *intel_dp,
+ const struct intel_crtc_state *crtc_state,
+ bool dpcd_updated) {}
+static inline void intel_dp_tunnel_suspend(struct intel_dp *intel_dp) {}
+
+static inline bool intel_dp_tunnel_bw_alloc_is_enabled(struct intel_dp *intel_dp)
+{
+ return false;
+}
+
+static inline void
+intel_dp_tunnel_atomic_cleanup_inherited_state(struct intel_atomic_state *state) {}
+
+static inline int
+intel_dp_tunnel_atomic_compute_stream_bw(struct intel_atomic_state *state,
+ struct intel_dp *intel_dp,
+ const struct intel_connector *connector,
+ struct intel_crtc_state *crtc_state)
+{
+ return 0;
+}
+
+static inline void
+intel_dp_tunnel_atomic_clear_stream_bw(struct intel_atomic_state *state,
+ struct intel_crtc_state *crtc_state) {}
+
+static inline int
+intel_dp_tunnel_atomic_add_state_for_crtc(struct intel_atomic_state *state,
+ struct intel_crtc *crtc)
+{
+ return 0;
+}
+
+static inline int
+intel_dp_tunnel_atomic_check_link(struct intel_atomic_state *state,
+ struct intel_link_bw_limits *limits)
+{
+ return 0;
+}
+
+static inline int
+intel_dp_tunnel_atomic_check_state(struct intel_atomic_state *state,
+ struct intel_dp *intel_dp,
+ struct intel_connector *connector)
+{
+ return 0;
+}
+
+static inline int
+intel_dp_tunnel_atomic_alloc_bw(struct intel_atomic_state *state)
+{
+ return 0;
+}
+
+static inline int
+intel_dp_tunnel_mgr_init(struct drm_i915_private *i915)
+{
+ return 0;
+}
+
+static inline void intel_dp_tunnel_mgr_cleanup(struct drm_i915_private *i915) {}
+
+#endif /* CONFIG_DRM_I915_DP_TUNNEL */
+
+#endif /* __INTEL_DP_TUNNEL_H__ */
--
2.39.2
