The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From c40a09e56fa3d17a3d06cec9a24b04364bb18c8f Mon Sep 17 00:00:00 2001 From: Nicholas Kazlauskas nicholas.kazlauskas@amd.com Date: Thu, 4 Nov 2021 16:52:07 -0400 Subject: [PATCH] drm/amd/display: Add callbacks for DMUB HPD IRQ notifications
[Why] We need HPD IRQ notifications (RX, short pulse) to properly handle DP MST for DPIA connections.
[How] A null pointer exception currently occurs when these are received so add a check to validate that we have a handler installed for the notification.
Extend the HPD handler to also handle HPD IRQ (RX) since the logic is the same.
Fixes: e27c41d5b068 ("drm/amd/display: Support for DMUB HPD interrupt handling")
Reviewed-by: Wayne Lin Wayne.Lin@amd.com Reviewed-by: Jude Shih shenshih@amd.com Acked-by: Anson Jacob Anson.Jacob@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Nicholas Kazlauskas nicholas.kazlauskas@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c index 6aafcc14b479..a7cf7df4d2f2 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -217,6 +217,7 @@ static const struct drm_format_info * amd_get_format_info(const struct drm_mode_fb_cmd2 *cmd);
static void handle_hpd_irq_helper(struct amdgpu_dm_connector *aconnector); +static void handle_hpd_rx_irq(void *param);
static bool is_timing_unchanged_for_freesync(struct drm_crtc_state *old_crtc_state, @@ -683,8 +684,12 @@ void dmub_hpd_callback(struct amdgpu_device *adev, struct dmub_notification *not } drm_connector_list_iter_end(&iter);
- if (hpd_aconnector) - handle_hpd_irq_helper(hpd_aconnector); + if (hpd_aconnector) { + if (notify->type == DMUB_NOTIFICATION_HPD) + handle_hpd_irq_helper(hpd_aconnector); + else if (notify->type == DMUB_NOTIFICATION_HPD_IRQ) + handle_hpd_rx_irq(hpd_aconnector); + } }
/** @@ -760,6 +765,10 @@ static void dm_dmub_outbox1_low_irq(void *interrupt_params) DRM_ERROR("DM: notify type %d invalid!", notify.type); continue; } + if (!dm->dmub_callback[notify.type]) { + DRM_DEBUG_DRIVER("DMUB notification skipped, no handler: type=%d\n", notify.type); + continue; + } if (dm->dmub_thread_offload[notify.type] == true) { dmub_hpd_wrk = kzalloc(sizeof(*dmub_hpd_wrk), GFP_ATOMIC); if (!dmub_hpd_wrk) { @@ -1560,6 +1569,10 @@ static int amdgpu_dm_init(struct amdgpu_device *adev) DRM_ERROR("amdgpu: fail to register dmub hpd callback"); goto error; } + if (!register_dmub_notify_callback(adev, DMUB_NOTIFICATION_HPD_IRQ, dmub_hpd_callback, true)) { + DRM_ERROR("amdgpu: fail to register dmub hpd callback"); + goto error; + } #endif /* CONFIG_DRM_AMD_DC_DCN */ }