From: Dave Stevenson <[email protected]> Audio can be triggered by the HPD handler and start up before video has been restored, calling vc4_hdmi_write_infoframe() for the audio infoframe. vc4_hdmi_write_infoframe() needs Packet RAM to be on to store the infoframe, however, if the video hasn't been enabled, vc4_hdmi_encoder_post_crtc_enable() hasn't been called and therefore, the Packet RAM can be disabled by the time vc4_hdmi_write_infoframe() executes, causing the following splat:
[ 201.570266] ------------[ cut here ]------------ [ 201.570293] Packet RAM has to be on to store the packet. [ 201.570367] WARNING: drivers/gpu/drm/vc4/vc4_hdmi.c:683 at vc4_hdmi_write_infoframe+0x404/0x494 [vc4], CPU#0: wireplumber/1606 [...] [ 201.658650] Hardware name: Raspberry Pi 4 Model B Rev 1.5 (DT) [...] [ 201.758499] Call trace: [ 201.760967] vc4_hdmi_write_infoframe+0x404/0x494 [vc4] (P) [ 201.766607] vc4_hdmi_write_audio_infoframe+0x1c/0x28 [vc4] [ 201.772247] write_infoframe+0xbc/0x140 [drm_display_helper] [ 201.777975] drm_atomic_helper_connector_hdmi_update_audio_infoframe+0x80/0xdc [drm_display_helper] [ 201.787140] vc4_hdmi_audio_prepare+0x4ac/0x570 [vc4] [ 201.792252] drm_connector_hdmi_audio_prepare+0x24/0x30 [drm_display_helper] [ 201.799390] hdmi_codec_prepare+0x100/0x160 [snd_soc_hdmi_codec] [ 201.805471] snd_soc_pcm_dai_prepare+0xd4/0x100 [snd_soc_core] [ 201.811375] __soc_pcm_prepare+0x60/0x12c [snd_soc_core] [ 201.816752] soc_pcm_prepare+0x34/0x58 [snd_soc_core] [ 201.821863] snd_pcm_do_prepare+0x70/0x8c [snd_pcm] [ 201.826798] snd_pcm_action_nonatomic+0xe4/0x174 [snd_pcm] [ 201.832350] snd_pcm_prepare+0xc8/0xd8 [snd_pcm] [ 201.837021] snd_pcm_common_ioctl+0x458/0x614 [snd_pcm] [ 201.842308] snd_pcm_ioctl+0x30/0x48 [snd_pcm] [ 201.846802] __arm64_sys_ioctl+0x88/0xd8 [ 201.850769] invoke_syscall+0x48/0xf4 [ 201.854470] el0_svc_common+0x80/0xd8 [ 201.858171] do_el0_svc+0x1c/0x28 [ 201.861520] el0_svc+0x3c/0xb0 [ 201.864605] el0t_64_sync_handler+0x68/0xdc [ 201.868834] el0t_64_sync+0x198/0x19c [ 201.872536] ---[ end trace 0000000000000000 ]--- Considering that Packet RAM enable is essentially a power management configuration, move its enabling/disabling to the Runtime PM hooks. Note that post_crtc_disable() still stops all infoframes, but keeps Packet RAM enabled, leaving it to be disabled by runtime suspend. Link: https://github.com/raspberrypi/linux/issues/7069 Fixes: b47a72f30768 ("drm/vc4: hdmi: Switch to HDMI connector") Signed-off-by: Dave Stevenson <[email protected]> Signed-off-by: Maíra Canal <[email protected]> --- drivers/gpu/drm/vc4/vc4_hdmi.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c index 17c8635c5afa..d4672aa81d85 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi.c +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c @@ -894,7 +894,7 @@ static void vc4_hdmi_encoder_post_crtc_disable(struct drm_encoder *encoder, spin_lock_irqsave(&vc4_hdmi->hw_lock, flags); - HDMI_WRITE(HDMI_RAM_PACKET_CONFIG, 0); + HDMI_WRITE(HDMI_RAM_PACKET_CONFIG, VC4_HDMI_RAM_PACKET_ENABLE); HDMI_WRITE(HDMI_VID_CTL, HDMI_READ(HDMI_VID_CTL) | VC4_HD_VID_CTL_CLRRGB); @@ -1663,9 +1663,6 @@ static void vc4_hdmi_encoder_post_crtc_enable(struct drm_encoder *encoder, WARN_ONCE(ret, "Timeout waiting for " "VC4_HDMI_SCHEDULER_CONTROL_HDMI_ACTIVE\n"); } else { - HDMI_WRITE(HDMI_RAM_PACKET_CONFIG, - HDMI_READ(HDMI_RAM_PACKET_CONFIG) & - ~(VC4_HDMI_RAM_PACKET_ENABLE)); HDMI_WRITE(HDMI_SCHEDULER_CONTROL, HDMI_READ(HDMI_SCHEDULER_CONTROL) & ~VC4_HDMI_SCHEDULER_CONTROL_MODE_HDMI); @@ -1684,9 +1681,6 @@ static void vc4_hdmi_encoder_post_crtc_enable(struct drm_encoder *encoder, WARN_ON(!(HDMI_READ(HDMI_SCHEDULER_CONTROL) & VC4_HDMI_SCHEDULER_CONTROL_HDMI_ACTIVE)); - HDMI_WRITE(HDMI_RAM_PACKET_CONFIG, - VC4_HDMI_RAM_PACKET_ENABLE); - spin_unlock_irqrestore(&vc4_hdmi->hw_lock, flags); vc4_hdmi->packet_ram_enabled = true; @@ -3143,6 +3137,11 @@ static int vc5_hdmi_init_resources(struct drm_device *drm, static int vc4_hdmi_runtime_suspend(struct device *dev) { struct vc4_hdmi *vc4_hdmi = dev_get_drvdata(dev); + unsigned long flags; + + spin_lock_irqsave(&vc4_hdmi->hw_lock, flags); + HDMI_WRITE(HDMI_RAM_PACKET_CONFIG, 0); + spin_unlock_irqrestore(&vc4_hdmi->hw_lock, flags); clk_disable_unprepare(vc4_hdmi->audio_clock); clk_disable_unprepare(vc4_hdmi->hsm_clock); @@ -3153,9 +3152,8 @@ static int vc4_hdmi_runtime_suspend(struct device *dev) static int vc4_hdmi_runtime_resume(struct device *dev) { struct vc4_hdmi *vc4_hdmi = dev_get_drvdata(dev); - unsigned long __maybe_unused flags; + unsigned long rate, flags; u32 __maybe_unused value; - unsigned long rate; int ret; ret = clk_prepare_enable(vc4_hdmi->hsm_clock); @@ -3201,6 +3199,10 @@ static int vc4_hdmi_runtime_resume(struct device *dev) } #endif + spin_lock_irqsave(&vc4_hdmi->hw_lock, flags); + HDMI_WRITE(HDMI_RAM_PACKET_CONFIG, VC4_HDMI_RAM_PACKET_ENABLE); + spin_unlock_irqrestore(&vc4_hdmi->hw_lock, flags); + return 0; err_disable_clk: -- 2.55.0
