Commit 851daf0c authored by Sean Anderson's avatar Sean Anderson Committed by Tomi Valkeinen
Browse files

drm: zynqmp_dp: Don't retrain the link in our IRQ 



Retraining the link can take a while, and might involve waiting for
DPCD reads/writes to complete. In preparation for unthreading the IRQ
handler, move this into its own work function.

Signed-off-by: default avatarSean Anderson <sean.anderson@linux.dev>
Signed-off-by: default avatarTomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240809193600.3360015-4-sean.anderson@linux.dev
parent a7d5eeaa

drivers/gpu/drm/xlnx/zynqmp_dp.c

+29 −16
Original line number Diff line number Diff line
@@ -289,6 +289,7 @@ struct zynqmp_dp_config { 
 * @phy: PHY handles for DP lanes

 * @num_lanes: number of enabled phy lanes

 * @hpd_work: hot plug detection worker

 * @hpd_irq_work: hot plug detection IRQ worker

 * @status: connection status

 * @enabled: flag to indicate if the device is enabled

 * @dpcd: DP configuration data from currently connected sink device
@@ -304,6 +305,7 @@ struct zynqmp_dp { 
	struct drm_dp_aux aux;

	struct drm_bridge bridge;

	struct work_struct hpd_work;

	struct work_struct hpd_irq_work;

	struct mutex lock;



	struct drm_bridge *next_bridge;
@@ -1671,6 +1673,29 @@ static void zynqmp_dp_hpd_work_func(struct work_struct *work) 
	drm_bridge_hpd_notify(&dp->bridge, status);

}



static void zynqmp_dp_hpd_irq_work_func(struct work_struct *work)

{

	struct zynqmp_dp *dp = container_of(work, struct zynqmp_dp,

					    hpd_irq_work);

	u8 status[DP_LINK_STATUS_SIZE + 2];

	int err;



	mutex_lock(&dp->lock);

	err = drm_dp_dpcd_read(&dp->aux, DP_SINK_COUNT, status,

			       DP_LINK_STATUS_SIZE + 2);

	if (err < 0) {

		dev_dbg_ratelimited(dp->dev,

				    "could not read sink status: %d\n", err);

	} else {

		if (status[4] & DP_LINK_STATUS_UPDATED ||

		    !drm_dp_clock_recovery_ok(&status[2], dp->mode.lane_cnt) ||

		    !drm_dp_channel_eq_ok(&status[2], dp->mode.lane_cnt)) {

			zynqmp_dp_train_loop(dp);

		}

	}

	mutex_unlock(&dp->lock);

}



static irqreturn_t zynqmp_dp_irq_handler(int irq, void *data)

{

	struct zynqmp_dp *dp = (struct zynqmp_dp *)data;
@@ -1702,23 +1727,9 @@ static irqreturn_t zynqmp_dp_irq_handler(int irq, void *data) 
	if (status & ZYNQMP_DP_INT_HPD_EVENT)

		schedule_work(&dp->hpd_work);



	if (status & ZYNQMP_DP_INT_HPD_IRQ) {

		int ret;

		u8 status[DP_LINK_STATUS_SIZE + 2];



		ret = drm_dp_dpcd_read(&dp->aux, DP_SINK_COUNT, status,

				       DP_LINK_STATUS_SIZE + 2);

		if (ret < 0)

			goto handled;



		if (status[4] & DP_LINK_STATUS_UPDATED ||

		    !drm_dp_clock_recovery_ok(&status[2], dp->mode.lane_cnt) ||

		    !drm_dp_channel_eq_ok(&status[2], dp->mode.lane_cnt)) {

			zynqmp_dp_train_loop(dp);

		}

	}

	if (status & ZYNQMP_DP_INT_HPD_IRQ)

		schedule_work(&dp->hpd_irq_work);



handled:

	return IRQ_HANDLED;

}
@@ -1744,6 +1755,7 @@ int zynqmp_dp_probe(struct zynqmp_dpsub *dpsub) 
	mutex_init(&dp->lock);



	INIT_WORK(&dp->hpd_work, zynqmp_dp_hpd_work_func);

	INIT_WORK(&dp->hpd_irq_work, zynqmp_dp_hpd_irq_work_func);



	/* Acquire all resources (IOMEM, IRQ and PHYs). */

	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dp");
@@ -1848,6 +1860,7 @@ void zynqmp_dp_remove(struct zynqmp_dpsub *dpsub) 
	zynqmp_dp_write(dp, ZYNQMP_DP_INT_DS, ZYNQMP_DP_INT_ALL);

	disable_irq(dp->irq);



	cancel_work_sync(&dp->hpd_irq_work);

	cancel_work_sync(&dp->hpd_work);



	zynqmp_dp_write(dp, ZYNQMP_DP_TRANSMITTER_ENABLE, 0);