[PATCH v7] mtd: rawnand: sunxi: Add MDMA support

[Boris Brezillon]

On Mon, 12 Oct 2020 17:41:22 +0200 (CEST)
Manuel Dipolt <mdipolt at robart.cc> wrote:

> @@ -363,24 +364,34 @@ static int sunxi_nfc_dma_op_prepare(struct sunxi_nfc *nfc, const void *buf,
>  	if (!ret)
>  		return -ENOMEM;
>  
> -	dmad = dmaengine_prep_slave_sg(nfc->dmac, sg, 1, tdir, DMA_CTRL_ACK);
> -	if (!dmad) {
> -		ret = -EINVAL;
> -		goto err_unmap_buf;
> +	if (!nfc->caps->has_mdma) {
> +		dmad = dmaengine_prep_slave_sg(nfc->dmac, sg, 1, tdir, DMA_CTRL_ACK);
> +		if (!dmad) {
> +			ret = -EINVAL;
> +			goto err_unmap_buf;
> +		}
>  	}
>  
>  	writel(readl(nfc->regs + NFC_REG_CTL) | NFC_RAM_METHOD,
>  	       nfc->regs + NFC_REG_CTL);
>  	writel(nchunks, nfc->regs + NFC_REG_SECTOR_NUM);
>  	writel(chunksize, nfc->regs + NFC_REG_CNT);
> -	if (nfc->caps->extra_mbus_conf)
> +
> +	if (nfc->caps->has_mdma) {
> +		writel(readl(nfc->regs + NFC_REG_CTL) & ~NFC_DMA_TYPE_NORMAL,
> +		       nfc->regs + NFC_REG_CTL);
>  		writel(chunksize * nchunks, nfc->regs + NFC_REG_MDMA_CNT);
> +		writel(sg_dma_address(sg), nfc->regs + NFC_REG_MDMA_ADDR);
> +	} else {
> +		writel(readl(nfc->regs + NFC_REG_CTL) | NFC_DMA_TYPE_NORMAL,
> +		       nfc->regs + NFC_REG_CTL);

You might want to try dropping this writel (looks like it was only done
when extra_mbus_conf was set).

>  
> -	dmat = dmaengine_submit(dmad);
> +		dmat = dmaengine_submit(dmad);
>  
> -	ret = dma_submit_error(dmat);
> -	if (ret)
> -		goto err_clr_dma_flag;
> +		ret = dma_submit_error(dmat);
> +		if (ret)
> +			goto err_clr_dma_flag;
> +	}
>  
>  	return 0;
>