[PATCH v11 47/74] drm/vc4: hdmi: Convert to common HDMI 2.0 scrambling infrastructure
From: Cristian Ciocaltea <hidden>
Date: 2026-09-01 18:51:37
Also in:
dri-devel, linux-arm-kernel, linux-rockchip, linux-sunxi, lkml
Subsystem:
drm drivers, drm drivers and misc gpu patches, drm drivers for vc4, the rest · Maintainers:
David Airlie, Simona Vetter, Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, Dave Stevenson, Linus Torvalds
Replace driver local scrambling logic with the newly introduced common
HDMI 2.0 scrambling support:
- Advertise source-side scrambling capability by setting supported HDMI
version based on the variant's max_pixel_clock.
- Provide minimal .scrambler_{enable,disable} connector callbacks that
only toggle the VC5 HDMI_SCRAMBLER_CTL register, while delegating
sink-side SCDC programming and periodic status monitoring to
drm_connector_hdmi_{enable,disable}_scrambling().
- Drop vc4_hdmi_reset_link() and vc4_hdmi_handle_hotplug(), switching
the .detect_ctx() path to drm_atomic_helper_connector_hdmi_hotplug()
which internally calls drm_connector_hdmi_sync_scdc() to trigger a
CRTC reset on reconnection.
- Drop the local scrambling_work delayed workqueue and scdc_enabled
flag, now tracked by the common drm_connector_hdmi layer, as well as
the now unused output_{bpc,color_format} driver data members.
No functional change intended.
Signed-off-by: Cristian Ciocaltea <redacted>
---
drivers/gpu/drm/vc4/vc4_hdmi.c | 230 +++++------------------------------------
drivers/gpu/drm/vc4/vc4_hdmi.h | 21 ----
2 files changed, 28 insertions(+), 223 deletions(-)
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index a03e50e8afcb..2451ff85e759 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c@@ -35,7 +35,6 @@ #include <drm/display/drm_hdmi_cec_helper.h> #include <drm/display/drm_hdmi_helper.h> #include <drm/display/drm_hdmi_state_helper.h> -#include <drm/display/drm_scdc_helper.h> #include <drm/drm_atomic_helper.h> #include <drm/drm_drv.h> #include <drm/drm_edid.h>
@@ -114,22 +113,6 @@ #define HSM_MIN_CLOCK_FREQ 120000000 #define CEC_CLOCK_FREQ 40000 -static bool vc4_hdmi_supports_scrambling(struct vc4_hdmi *vc4_hdmi) -{ - struct drm_display_info *display = &vc4_hdmi->connector.display_info; - - lockdep_assert_held(&vc4_hdmi->mutex); - - if (!display->is_hdmi) - return false; - - if (!display->hdmi.scdc.supported || - !display->hdmi.scdc.scrambling.supported) - return false; - - return true; -} - static int vc4_hdmi_debugfs_regs(struct seq_file *m, void *unused) { struct drm_debugfs_entry *entry = m->private;
@@ -263,115 +246,6 @@ static void vc4_hdmi_cec_update_clk_div(struct vc4_hdmi *vc4_hdmi) static void vc4_hdmi_cec_update_clk_div(struct vc4_hdmi *vc4_hdmi) {} #endif -static int vc4_hdmi_reset_link(struct drm_connector *connector, - struct drm_modeset_acquire_ctx *ctx) -{ - struct drm_device *drm; - struct vc4_hdmi *vc4_hdmi; - struct drm_connector_state *conn_state; - struct drm_crtc_state *crtc_state; - struct drm_crtc *crtc; - bool scrambling_needed; - u8 config; - int ret; - - if (!connector) - return 0; - - drm = connector->dev; - ret = drm_modeset_lock(&drm->mode_config.connection_mutex, ctx); - if (ret) - return ret; - - conn_state = connector->state; - crtc = conn_state->crtc; - if (!crtc) - return 0; - - ret = drm_modeset_lock(&crtc->mutex, ctx); - if (ret) - return ret; - - crtc_state = crtc->state; - if (!crtc_state->active) - return 0; - - vc4_hdmi = connector_to_vc4_hdmi(connector); - mutex_lock(&vc4_hdmi->mutex); - - if (!vc4_hdmi_supports_scrambling(vc4_hdmi)) { - mutex_unlock(&vc4_hdmi->mutex); - return 0; - } - - scrambling_needed = drm_hdmi_mode_needs_scrambling(&vc4_hdmi->saved_adjusted_mode, - vc4_hdmi->output_bpc, - vc4_hdmi->output_format); - if (!scrambling_needed) { - mutex_unlock(&vc4_hdmi->mutex); - return 0; - } - - if (conn_state->commit && - !try_wait_for_completion(&conn_state->commit->hw_done)) { - mutex_unlock(&vc4_hdmi->mutex); - return 0; - } - - ret = drm_scdc_readb(connector->ddc, SCDC_TMDS_CONFIG, &config); - if (ret < 0) { - drm_err(drm, "Failed to read TMDS config: %d\n", ret); - mutex_unlock(&vc4_hdmi->mutex); - return 0; - } - - if (!!(config & SCDC_SCRAMBLING_ENABLE) == scrambling_needed) { - mutex_unlock(&vc4_hdmi->mutex); - return 0; - } - - mutex_unlock(&vc4_hdmi->mutex); - - /* - * HDMI 2.0 says that one should not send scrambled data - * prior to configuring the sink scrambling, and that - * TMDS clock/data transmission should be suspended when - * changing the TMDS clock rate in the sink. So let's - * just do a full modeset here, even though some sinks - * would be perfectly happy if were to just reconfigure - * the SCDC settings on the fly. - */ - return drm_atomic_helper_reset_crtc(crtc, ctx); -} - -static int vc4_hdmi_handle_hotplug(struct vc4_hdmi *vc4_hdmi, - struct drm_modeset_acquire_ctx *ctx, - enum drm_connector_status status) -{ - struct drm_connector *connector = &vc4_hdmi->connector; - - /* - * NOTE: This function should really be called with vc4_hdmi->mutex - * held, but doing so results in reentrancy issues since - * cec_s_phys_addr() might call .adap_enable, which leads to that - * funtion being called with our mutex held. - * - * A similar situation occurs with vc4_hdmi_reset_link() that - * will call into our KMS hooks if the scrambling was enabled. - * - * Concurrency isn't an issue at the moment since we don't share - * any state with any of the other frameworks so we can ignore - * the lock for now. - */ - - drm_atomic_helper_connector_hdmi_hotplug(connector, ctx, status); - - if (status != connector_status_connected) - return 0; - - return vc4_hdmi_reset_link(connector, ctx); -} - static int vc4_hdmi_connector_detect_ctx(struct drm_connector *connector, struct drm_modeset_acquire_ctx *ctx, bool force)
@@ -383,8 +257,8 @@ static int vc4_hdmi_connector_detect_ctx(struct drm_connector *connector, /* * NOTE: This function should really take vc4_hdmi->mutex, but * doing so results in reentrancy issues since - * vc4_hdmi_handle_hotplug() can call into other functions that - * would take the mutex while it's held here. + * drm_atomic_helper_connector_hdmi_hotplug() can call into other + * functions that would take the mutex while it's held here. * * Concurrency isn't an issue at the moment since we don't share * any state with any of the other frameworks so we can ignore
@@ -407,7 +281,8 @@ static int vc4_hdmi_connector_detect_ctx(struct drm_connector *connector, status = connector_status_connected; } - ret = vc4_hdmi_handle_hotplug(vc4_hdmi, ctx, status); + ret = drm_atomic_helper_connector_hdmi_hotplug(connector, ctx, status); + pm_runtime_put(&vc4_hdmi->pdev->dev); return ret == -EDEADLK ? ret : status;
@@ -535,6 +410,14 @@ static int vc4_hdmi_connector_init(struct drm_device *dev, drm_connector_helper_add(connector, &vc4_hdmi_connector_helper_funcs); + /* + * Since we don't know the state of the controller and its + * display (if any), let's assume it's always enabled. + * drm_connector_hdmi_disable_scrambling() will thus run at boot, + * make sure it's disabled, and avoid any inconsistency. + */ + connector->hdmi.scrambler_enabled = drm_connector_hdmi_scrambler_supported(connector); + /* * Some of the properties below require access to state, like bpc. * Allocate some default initial connector state with our reset helper.
@@ -760,32 +643,15 @@ static int vc4_hdmi_write_spd_infoframe(struct drm_connector *connector, buffer, len); } -#define SCRAMBLING_POLLING_DELAY_MS 1000 - -static void vc4_hdmi_enable_scrambling(struct drm_encoder *encoder) +static int vc4_hdmi_scrambler_enable(struct drm_connector *connector) { - struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder); - struct drm_connector *connector = &vc4_hdmi->connector; + struct vc4_hdmi *vc4_hdmi = connector_to_vc4_hdmi(connector); struct drm_device *drm = connector->dev; - const struct drm_display_mode *mode = &vc4_hdmi->saved_adjusted_mode; unsigned long flags; int idx; - lockdep_assert_held(&vc4_hdmi->mutex); - - if (!vc4_hdmi_supports_scrambling(vc4_hdmi)) - return; - - if (!drm_hdmi_mode_needs_scrambling(mode, - vc4_hdmi->output_bpc, - vc4_hdmi->output_format)) - return; - if (!drm_dev_enter(drm, &idx)) - return; - - drm_scdc_set_high_tmds_clock_ratio(connector, true); - drm_scdc_set_scrambling(connector, true); + return 0; spin_lock_irqsave(&vc4_hdmi->hw_lock, flags); HDMI_WRITE(HDMI_SCRAMBLER_CTL, HDMI_READ(HDMI_SCRAMBLER_CTL) |
@@ -794,59 +660,27 @@ static void vc4_hdmi_enable_scrambling(struct drm_encoder *encoder) drm_dev_exit(idx); - vc4_hdmi->scdc_enabled = true; - - queue_delayed_work(system_percpu_wq, &vc4_hdmi->scrambling_work, - msecs_to_jiffies(SCRAMBLING_POLLING_DELAY_MS)); + return 0; } -static void vc4_hdmi_disable_scrambling(struct drm_encoder *encoder) +static int vc4_hdmi_scrambler_disable(struct drm_connector *connector) { - struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder); - struct drm_connector *connector = &vc4_hdmi->connector; + struct vc4_hdmi *vc4_hdmi = connector_to_vc4_hdmi(connector); struct drm_device *drm = connector->dev; unsigned long flags; int idx; - lockdep_assert_held(&vc4_hdmi->mutex); - - if (!vc4_hdmi->scdc_enabled) - return; - - vc4_hdmi->scdc_enabled = false; - - if (delayed_work_pending(&vc4_hdmi->scrambling_work)) - cancel_delayed_work_sync(&vc4_hdmi->scrambling_work); - if (!drm_dev_enter(drm, &idx)) - return; + return 0; spin_lock_irqsave(&vc4_hdmi->hw_lock, flags); HDMI_WRITE(HDMI_SCRAMBLER_CTL, HDMI_READ(HDMI_SCRAMBLER_CTL) & ~VC5_HDMI_SCRAMBLER_CTL_ENABLE); spin_unlock_irqrestore(&vc4_hdmi->hw_lock, flags); - drm_scdc_set_scrambling(connector, false); - drm_scdc_set_high_tmds_clock_ratio(connector, false); - drm_dev_exit(idx); -} -static void vc4_hdmi_scrambling_wq(struct work_struct *work) -{ - struct vc4_hdmi *vc4_hdmi = container_of(to_delayed_work(work), - struct vc4_hdmi, - scrambling_work); - struct drm_connector *connector = &vc4_hdmi->connector; - - if (drm_scdc_get_scrambling_status(connector)) - return; - - drm_scdc_set_high_tmds_clock_ratio(connector, true); - drm_scdc_set_scrambling(connector, true); - - queue_delayed_work(system_percpu_wq, &vc4_hdmi->scrambling_work, - msecs_to_jiffies(SCRAMBLING_POLLING_DELAY_MS)); + return 0; } static void vc4_hdmi_encoder_post_crtc_disable(struct drm_encoder *encoder,
@@ -891,7 +725,7 @@ static void vc4_hdmi_encoder_post_crtc_disable(struct drm_encoder *encoder, spin_unlock_irqrestore(&vc4_hdmi->hw_lock, flags); } - vc4_hdmi_disable_scrambling(encoder); + drm_connector_hdmi_disable_scrambling(&vc4_hdmi->connector); drm_dev_exit(idx);
@@ -1599,6 +1433,7 @@ static void vc4_hdmi_encoder_post_crtc_enable(struct drm_encoder *encoder, struct drm_display_info *display = &vc4_hdmi->connector.display_info; bool hsync_pos = mode->flags & DRM_MODE_FLAG_PHSYNC; bool vsync_pos = mode->flags & DRM_MODE_FLAG_PVSYNC; + struct drm_connector_state *conn_state; unsigned long flags; int ret; int idx;
@@ -1667,7 +1502,9 @@ static void vc4_hdmi_encoder_post_crtc_enable(struct drm_encoder *encoder, } vc4_hdmi_recenter_fifo(vc4_hdmi); - vc4_hdmi_enable_scrambling(encoder); + + conn_state = drm_atomic_get_new_connector_state(state, connector); + drm_connector_hdmi_enable_scrambling(connector, conn_state); drm_dev_exit(idx);
@@ -1684,8 +1521,6 @@ static void vc4_hdmi_encoder_atomic_mode_set(struct drm_encoder *encoder, mutex_lock(&vc4_hdmi->mutex); drm_mode_copy(&vc4_hdmi->saved_adjusted_mode, &crtc_state->adjusted_mode); - vc4_hdmi->output_bpc = conn_state->hdmi.output_bpc; - vc4_hdmi->output_format = conn_state->hdmi.output_format; mutex_unlock(&vc4_hdmi->mutex); }
@@ -1755,8 +1590,9 @@ static const struct drm_connector_hdmi_funcs vc4_hdmi_connector_funcs_hdmi14 = { static const struct drm_connector_hdmi_funcs vc4_hdmi_connector_funcs_hdmi20 = { VC4_HDMI_CONNECTOR_FUNCS_COMMON, .max_bpc = 12, - /* TODO: set HDMI_VERSION_2_0 and convert to common scrambler infra */ - .supported_hdmi_ver = HDMI_VERSION_UNKNOWN, + .supported_hdmi_ver = HDMI_VERSION_2_0, + .scrambler_enable = vc4_hdmi_scrambler_enable, + .scrambler_disable = vc4_hdmi_scrambler_disable, }; #define WIFI_2_4GHz_CH1_MIN_FREQ 2400000000ULL
@@ -3230,7 +3066,6 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data) return ret; spin_lock_init(&vc4_hdmi->hw_lock); - INIT_DELAYED_WORK(&vc4_hdmi->scrambling_work, vc4_hdmi_scrambling_wq); dev_set_drvdata(dev, vc4_hdmi); encoder = &vc4_hdmi->encoder.base;
@@ -3243,15 +3078,6 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data) vc4_hdmi->pdev = pdev; vc4_hdmi->variant = variant; - /* - * Since we don't know the state of the controller and its - * display (if any), let's assume it's always enabled. - * vc4_hdmi_disable_scrambling() will thus run at boot, make - * sure it's disabled, and avoid any inconsistency. - */ - if (variant->max_pixel_clock > HDMI_1_3_TMDS_CHAR_RATE_MAX_HZ) - vc4_hdmi->scdc_enabled = true; - ret = variant->init_resources(drm, vc4_hdmi); if (ret) return ret;
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.h b/drivers/gpu/drm/vc4/vc4_hdmi.h
index d5ffcc17de32..f6159c9e6144 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.h
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.h@@ -118,8 +118,6 @@ struct vc4_hdmi { struct vc4_encoder encoder; struct drm_connector connector; - struct delayed_work scrambling_work; - struct i2c_adapter *ddc; void __iomem *hdmicore_regs; void __iomem *hd_regs;
@@ -193,25 +191,6 @@ struct vc4_hdmi { */ bool packet_ram_enabled; - /** - * @scdc_enabled: Is the HDMI controller currently running with - * the scrambler on? Protected by @mutex. - */ - bool scdc_enabled; - - /** - * @output_bpc: Copy of @drm_connector_state.hdmi.output_bpc for - * use outside of KMS hooks. Protected by @mutex. - */ - unsigned int output_bpc; - - /** - * @output_format: Copy of - * @drm_connector_state.hdmi.output_format for use outside of - * KMS hooks. Protected by @mutex. - */ - enum drm_output_color_format output_format; - /** * @hdmi_jack: Represents the connection state of the HDMI plug, for * ALSA jack detection.
--
2.55.0