[PATCH v4 2/3] net: can: rockchip: add can for RK3576 Soc

Marc Kleine-Budde mkl at pengutronix.de
Thu May 22 02:21:54 PDT 2025


On 22.05.2025 15:46:15, Elaine Zhang wrote:
> Is new controller:
> Support CAN and CANFD protocol.
> Support Dma.
> 
> Signed-off-by: Elaine Zhang <zhangqing at rock-chips.com>
> ---

Looking at the rkcanfd_probe() only for now.

>  static int rkcanfd_probe(struct platform_device *pdev)
>  {
>  	struct rkcanfd_priv *priv;
>  	struct net_device *ndev;
> +	struct resource *res;
>  	const void *match;
> -	int err;
> +	int err, val;
>  
>  	ndev = alloc_candev(sizeof(struct rkcanfd_priv), RKCANFD_TXFIFO_DEPTH);
>  	if (!ndev)
> @@ -883,6 +1396,7 @@ static int rkcanfd_probe(struct platform_device *pdev)
>  		goto out_free_candev;
>  	}
>  
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>  	priv->regs = devm_platform_ioremap_resource(pdev, 0);
>  	if (IS_ERR(priv->regs)) {
>  		err = PTR_ERR(priv->regs);
> @@ -912,13 +1426,46 @@ static int rkcanfd_probe(struct platform_device *pdev)
>  	priv->can.do_set_mode = rkcanfd_set_mode;
>  	priv->can.do_get_berr_counter = rkcanfd_get_berr_counter;
>  	priv->ndev = ndev;
> +	priv->dev = &pdev->dev;
>  
>  	match = device_get_match_data(&pdev->dev);
>  	if (match)
>  		priv->devtype_data = *(struct rkcanfd_devtype_data *)match;
>  
> +	if (device_property_read_u32(&pdev->dev, "rockchip,auto-retx-cnt", &val))
> +		priv->auto_retx_cnt = 0;
> +	else
> +		priv->auto_retx_cnt = val;

What does "rockchip,auto-retx-cnt" do?

> +	if (priv->auto_retx_cnt > RK3576CANFD_RETX_TIME_LIMIT_CNT_MAX)
> +		priv->auto_retx_cnt = RK3576CANFD_RETX_TIME_LIMIT_CNT_MAX;
> +
> +	/* rx-max-data only 4 Words or 18 words are supported */
> +	if (device_property_read_u32_array(&pdev->dev, "rockchip,rx-max-data", &val, 1))
> +		priv->rx_max_data = 18;
> +	else
> +		priv->rx_max_data = val;

What does "rockchip,rx-max-data" do?

> +	if (priv->rx_max_data != 4 && priv->rx_max_data != 18) {
> +		priv->rx_max_data = 18;
> +		dev_warn(&pdev->dev, "rx_max_data is invalid, set to 18 words!\n");
> +	}
> +	priv->rx_fifo_depth = RK3576CANFD_SRAM_MAX_DEPTH / priv->rx_max_data;
> +
> +	priv->rxchan = dma_request_chan(&pdev->dev, "rx");
> +	if (IS_ERR(priv->rxchan)) {
> +		dev_warn(&pdev->dev, "Failed to request rxchan\n");
> +		priv->rxchan = NULL;
> +		priv->use_dma = 0;
> +	} else {
> +		priv->rx_dma_src_addr = res->start + RK3576CANFD_REG_RXFRD;
> +		priv->dma_size = priv->rx_max_data * 4;
> +		priv->use_dma = 1;
> +	}
> +	if (priv->use_dma)
> +		rk3576_canfd_dma_init(priv);
> +
>  	err = can_rx_offload_add_manual(ndev, &priv->offload,
> -					RKCANFD_NAPI_WEIGHT);
> +					MAX(RKCANFD_NAPI_WEIGHT, priv->rx_fifo_depth));
>  	if (err)
>  		goto out_free_candev;

regards,
Marc

-- 
Pengutronix e.K.                 | Marc Kleine-Budde          |
Embedded Linux                   | https://www.pengutronix.de |
Vertretung Nürnberg              | Phone: +49-5121-206917-129 |
Amtsgericht Hildesheim, HRA 2686 | Fax:   +49-5121-206917-9   |
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