On 9/27/20 6:07 PM, Joakim Zhang wrote:
[...]

> +static void flexcan_init_ram(struct net_device *dev)
> +{
> +	struct flexcan_priv *priv = netdev_priv(dev);
> +	struct flexcan_regs __iomem *regs = priv->regs;
> +	u32 reg_ctrl2;
> +	int i;
> +
> +	/* 11.8.3.13 Detection and correction of memory errors:
> +	 * CTRL2[WRMFRZ] grants write access to all memory positions that
> +	 * require initialization, ranging from 0x080 to 0xADF and
> +	 * from 0xF28 to 0xFFF when the CAN FD feature is enabled.
> +	 * The RXMGMASK, RX14MASK, RX15MASK, and RXFGMASK registers need to
> +	 * be initialized as well. MCR[RFEN] must not be set during memory
> +	 * initialization.
> +	 */
> +	reg_ctrl2 = priv->read(&regs->ctrl2);
> +	reg_ctrl2 |= FLEXCAN_CTRL2_WRMFRZ;
> +	priv->write(reg_ctrl2, &regs->ctrl2);
> +
> +	for (i = 0; i < ram_init[0].len; i++)
> +		priv->write(0, (void __iomem *)regs + ram_init[0].offset + sizeof(u32) * i);

As the write function only does endian conversion, and you're writing 0 here.
What about using iowrite32_rep() and get rid of the for loop?

Marc

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