[PATCH v2 9/9] misc: xilinx-ai-engine: Add support for servicing error interrupts

[Hillf Danton]

On Wed, 18 Nov 2020 15:48:09 -0800 Wendy Liang wrote:
> +/**
> + * aie_interrupt() - interrupt handler for AIE.
> + * @irq: Interrupt number.
> + * @data: AI engine device structure.
> + * @return: IRQ_HANDLED.
> + *
> + * This thread function disables level 2 interrupt controllers and schedules a
> + * task in workqueue to backtrack the source of error interrupt. Disabled
> + * interrupts are re-enabled after successful completion of bottom half.
> + */
> +irqreturn_t aie_interrupt(int irq, void *data)
> +{
> +	struct aie_device *adev = data;
> +	struct aie_partition *apart;
> +	int ret;
> +	bool sched_work = false;
> +
> +	ret = mutex_lock_interruptible(&adev->mlock);
> +	if (ret) {
> +		dev_err(&adev->dev,
> +			"Failed to acquire lock. Process was interrupted by fatal signals\n");
> +		return IRQ_NONE;
> +	}
> +
> +	list_for_each_entry(apart, &adev->partitions, node) {
> +		struct aie_location loc;
> +		u32 ttype, l2_mask, l2_status, l2_bitmap_offset  = 0;
> +
> +		ret = mutex_lock_interruptible(&apart->mlock);
> +		if (ret) {
> +			dev_err(&apart->dev,
> +				"Failed to acquire lock. Process was interrupted by fatal signals\n");
> +			return IRQ_NONE;

Though quite unlikely, you need to release adev->mlock before
going home.

> +		}
> +
> +		for (loc.col = apart->range.start.col, loc.row = 0;
> +		     loc.col < apart->range.start.col + apart->range.size.col;
> +		     loc.col++) {
> +			ttype = apart->adev->ops->get_tile_type(&loc);
> +			if (ttype != AIE_TILE_TYPE_SHIMNOC)
> +				continue;
> +
> +			l2_mask = aie_get_l2_mask(apart, &loc);
> +			if (l2_mask) {
> +				aie_resource_cpy_from_arr32(&apart->l2_mask,
> +							    l2_bitmap_offset  *
> +							    32, &l2_mask, 32);
> +				aie_disable_l2_ctrl(apart, &loc, l2_mask);
> +			}
> +			l2_bitmap_offset++;
> +
> +			l2_status = aie_get_l2_status(apart, &loc);
> +			if (l2_status) {
> +				aie_clear_l2_intr(apart, &loc, l2_status);
> +				sched_work = true;
> +			} else {
> +				aie_enable_l2_ctrl(apart, &loc, l2_mask);
> +			}
> +		}
> +		mutex_unlock(&apart->mlock);
> +	}
> +
> +	/* For ES1 silicon, interrupts are latched in NPI */
> +	if (adev->version == VERSAL_ES1_REV_ID) {
> +		ret = zynqmp_pm_clear_aie_npi_isr(adev->pm_node_id,
> +						  AIE_NPI_ERROR_ID);
> +		if (ret < 0)
> +			dev_err(&adev->dev, "Failed to clear NPI ISR\n");
> +	}
> +
> +	mutex_unlock(&adev->mlock);
> +
> +	if (sched_work)
> +		schedule_work(&adev->backtrack);
> +
> +	return IRQ_HANDLED;
> +}