Re: [PATCH v12 5/7] media: chips-media: wave5: Add the v4l2 layer

[Ivan Bornyakov]

Hi, Sebastian,

On Fri, Sep 15, 2023 at 23:11:34 +0200, Sebastian Fricke wrote:
> From: Nas Chung <nas.chung@xxxxxxxxxxxxxxx>
> 
> Add the decoder and encoder implementing the v4l2
> API. This patch also adds the Makefile and the VIDEO_WAVE_VPU config
> 
> Signed-off-by: Sebastian Fricke <sebastian.fricke@xxxxxxxxxxxxx>
> Signed-off-by: Nicolas Dufresne <nicolas.dufresne@xxxxxxxxxxxxx>
> Signed-off-by: Robert Beckett <bob.beckett@xxxxxxxxxxxxx>
> Signed-off-by: Dafna Hirschfeld <dafna.hirschfeld@xxxxxxxxxxxxx>
> Signed-off-by: Nas Chung <nas.chung@xxxxxxxxxxxxxxx>

[...]

> diff --git a/drivers/media/platform/chips-media/wave5/wave5-vpu.c b/drivers/media/platform/chips-media/wave5/wave5-vpu.c
> new file mode 100644
> index 000000000000..a13d968f5d04
> --- /dev/null
> +++ b/drivers/media/platform/chips-media/wave5/wave5-vpu.c

[...]

> +static void wave5_vpu_get_interrupt_for_inst(struct vpu_instance *inst, u32 status)
> +{
> +	struct vpu_device *dev = inst->dev;
> +	u32 seq_done;
> +	u32 cmd_done;
> +	int val;
> +
> +	seq_done = wave5_vdi_read_register(dev, W5_RET_SEQ_DONE_INSTANCE_INFO);
> +	cmd_done = wave5_vdi_read_register(dev, W5_RET_QUEUE_CMD_DONE_INST);
> +
> +	if (status & BIT(INT_WAVE5_INIT_SEQ)) {
> +		if (seq_done & BIT(inst->id)) {
> +			seq_done &= ~BIT(inst->id);
> +			wave5_vdi_write_register(dev, W5_RET_SEQ_DONE_INSTANCE_INFO, seq_done);
> +			val = BIT(INT_WAVE5_INIT_SEQ);
> +			kfifo_in(&inst->irq_status, &val, sizeof(int));
> +		}
> +	}
> +	if (status & BIT(INT_WAVE5_ENC_SET_PARAM)) {
> +		if (seq_done & BIT(inst->id)) {
> +			seq_done &= ~BIT(inst->id);
> +			wave5_vdi_write_register(dev, W5_RET_SEQ_DONE_INSTANCE_INFO, seq_done);
> +			val = BIT(INT_WAVE5_ENC_SET_PARAM);
> +			kfifo_in(&inst->irq_status, &val, sizeof(int));
> +		}
> +	}
> +	if (status & BIT(INT_WAVE5_DEC_PIC) ||
> +	    status & BIT(INT_WAVE5_ENC_PIC)) {
> +		if (cmd_done & BIT(inst->id)) {
> +			cmd_done &= ~BIT(inst->id);
> +			wave5_vdi_write_register(dev, W5_RET_QUEUE_CMD_DONE_INST, cmd_done);
> +			val = BIT(INT_WAVE5_DEC_PIC);
> +			kfifo_in(&inst->irq_status, &val, sizeof(int));
> +		}
> +	}
> +}
> +
> +static irqreturn_t wave5_vpu_irq(int irq, void *dev_id)
> +{
> +	struct vpu_device *dev = dev_id;
> +
> +	if (wave5_vdi_read_register(dev, W5_VPU_VPU_INT_STS)) {
> +		struct vpu_instance *inst;
> +		u32 irq_status = wave5_vdi_read_register(dev, W5_VPU_VINT_REASON);
> +
> +		list_for_each_entry(inst, &dev->instances, list) {
> +			wave5_vpu_get_interrupt_for_inst(inst, irq_status);
> +		}
> +
> +		wave5_vdi_write_register(dev, W5_VPU_VINT_REASON_CLR, irq_status);
> +		wave5_vdi_write_register(dev, W5_VPU_VINT_CLEAR, 0x1);
> +
> +		return IRQ_WAKE_THREAD;
> +	}
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t wave5_vpu_irq_thread(int irq, void *dev_id)
> +{
> +	struct vpu_device *dev = dev_id;
> +	struct vpu_instance *inst;
> +	int irq_status, ret;
> +
> +	list_for_each_entry(inst, &dev->instances, list) {
> +		while (kfifo_len(&inst->irq_status)) {
> +			ret = kfifo_out(&inst->irq_status, &irq_status, sizeof(int));
> +			if (!ret)
> +				break;
> +
> +			if (irq_status == BIT(INT_WAVE5_INIT_SEQ) ||
> +			    irq_status == BIT(INT_WAVE5_ENC_SET_PARAM))
> +				complete(&inst->irq_done);
> +			else /* DEC/ENC_PIC */
> +				inst->ops->finish_process(inst);
> +
> +			wave5_vpu_clear_interrupt(inst, irq_status);
> +		}
> +	}
> +
> +	return IRQ_HANDLED;
> +}

I believe, instead of
wave5_vpu_irq() + wave5_vpu_get_interrupt_for_inst() + wave5_vpu_irq_thread()
you can reduce interrupt handling to only threaded part with something like this:

static irqreturn_t wave5_vpu_irq_thread(int irq, void *dev_id)
{
	u32 irq_status, seq_done, cmd_done;
	struct vpu_device *dev = dev_id;
	struct vpu_instance *inst;

	while (wave5_vdi_read_register(dev, W5_VPU_VPU_INT_STS)) {
		irq_status = wave5_vdi_read_register(dev, W5_VPU_VINT_REASON);
		seq_done = wave5_vdi_read_register(dev, W5_RET_SEQ_DONE_INSTANCE_INFO);
		cmd_done = wave5_vdi_read_register(dev, W5_RET_QUEUE_CMD_DONE_INST);

		list_for_each_entry(inst, &dev->instances, list) {
			if (irq_status & BIT(INT_WAVE5_INIT_SEQ) ||
			    irq_status & BIT(INT_WAVE5_ENC_SET_PARAM)) {
				if (seq_done & BIT(inst->id)) {
					seq_done &= ~BIT(inst->id);
					wave5_vdi_write_register(dev,
								 W5_RET_SEQ_DONE_INSTANCE_INFO,
								 seq_done);
					complete(&inst->irq_done);
				}
			}

			if (status & BIT(INT_WAVE5_DEC_PIC) ||
			    status & BIT(INT_WAVE5_ENC_PIC)) {
				if (cmd_done & BIT(inst->id)) {
					cmd_done &= ~BIT(inst->id);
					wave5_vdi_write_register(dev,
								 W5_RET_QUEUE_CMD_DONE_INST,
								 cmd_done);
					inst->ops->finish_process(inst);
				}
			}

			wave5_vpu_clear_interrupt(inst, irq_status);
		}
			
		wave5_vdi_write_register(dev, W5_VPU_VINT_REASON_CLR, irq_status);
		wave5_vdi_write_register(dev, W5_VPU_VINT_CLEAR, 0x1);
	}

	return IRQ_HANDLED;
}

Is it better?

[...]

> +static int wave5_vpu_probe(struct platform_device *pdev)
> +{
> +	int ret;
> +	struct vpu_device *dev;
> +	const struct wave5_match_data *match_data;
> +	u32 fw_revision;
> +
> +	match_data = device_get_match_data(&pdev->dev);
> +	if (!match_data) {
> +		dev_err(&pdev->dev, "missing device match data\n");
> +		return -EINVAL;
> +	}
> +
> +	/* physical addresses limited to 32 bits */
> +	dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));
> +	dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));

dma_set_mask_and_coherent()? Also error check?