[PATCH 4/4] dma: ti: k3-udma: Move DMA channel[0] allocation to probe and add udma_remove()

[Kumar, Udit]

On 10/4/2024 6:50 PM, Prasanth Babu Mantena wrote:
> From: Santhosh Kumar K <s-k6 at ti.com>
>
> Currently, the allocation of DMA channel[0] for memcpy is happening
> in udma_transfer() for every transfer, which leads to a huge overhead
> for each transfer, especially in case of nand page reads. So, move this

> [..]
>   
> @@ -2590,6 +2565,7 @@ static int udma_probe(struct udevice *dev)
>   	struct udevice *tmp;
>   	struct udevice *tisci_dev = NULL;
>   	struct udma_tisci_rm *tisci_rm = &ud->tisci_rm;
> +	struct udma_chan *uc;
>   	ofnode navss_ofnode = ofnode_get_parent(dev_ofnode(dev));
>   
>   	ud->match_data = (void *)dev_get_driver_data(dev);
> @@ -2714,6 +2690,42 @@ static int udma_probe(struct udevice *dev)
>   
>   	uc_priv->supported = DMA_SUPPORTS_MEM_TO_MEM | DMA_SUPPORTS_MEM_TO_DEV;
>   
> +	uc = &ud->channels[0];
> +	switch (ud->match_data->type) {
> +	case DMA_TYPE_UDMA:
> +		ret = udma_alloc_chan_resources(uc);
> +		break;
> +	case DMA_TYPE_BCDMA:
> +		ret = bcdma_alloc_chan_resources(uc);
> +		break;
> +	default:
> +		return -EINVAL;

shouldn't we treat this default case as error and do some dev_err prints ?


> +	};
> +
> +	if (ret) {
> +		dev_err(dev, " Channel 0 allocation failure %d\n", ret);
> +		return ret;

No need of this ret


> +	}
> +
> +	return 0;


do 'return ret' here


> +}
> +
> +static int udma_remove(struct udevice *dev)
> +{
> +	struct udma_dev *ud = dev_get_priv(dev);
> +	struct udma_chan *uc = &ud->channels[0];
> +
> +	switch (ud->match_data->type) {
> +	case DMA_TYPE_UDMA:
> +		udma_free_chan_resources(uc);
> +		break;
> +	case DMA_TYPE_BCDMA:
> +		bcdma_free_bchan_resources(uc);
> +		break;
> +	default:
> +		return -EINVAL;

shouldn't we treat this default case as error and do some dev_err prints ?


> +	};
> +
>   	return 0;
>   }
>   
> @@ -2855,5 +2867,7 @@ U_BOOT_DRIVER(ti_edma3) = {
>   	.of_match = udma_ids,
>   	.ops	= &udma_ops,
>   	.probe	= udma_probe,
> +	.remove = udma_remove,
>   	.priv_auto	= sizeof(struct udma_dev),
> +	.flags  = DM_FLAG_OS_PREPARE,
>   };