Re: [PATCH v2 4/5] spi: spi-mtk-nor: support 36bit dma addressing to mediatek

[Yingjoe Chen <yingjoe.chen@mediatek.com>]

On Fri, 2020-09-18 at 16:31 +0800, Ikjoon Jang wrote:
> This patch enables 36bit dma address support to spi-mtk-nor.
> Currently 36bit dma addressing is enabled only for mt8192-nor.
> 
> Signed-off-by: Ikjoon Jang <ikjn@chromium.org>
> ---
> 
> (no changes since v1)
> 
>  drivers/spi/spi-mtk-nor.c | 19 ++++++++++++++++++-
>  1 file changed, 18 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/spi/spi-mtk-nor.c b/drivers/spi/spi-mtk-nor.c
> index e14798a6e7d0..99dd5dca744e 100644
> --- a/drivers/spi/spi-mtk-nor.c
> +++ b/drivers/spi/spi-mtk-nor.c
> @@ -78,6 +78,8 @@
>  #define MTK_NOR_REG_DMA_FADR		0x71c
>  #define MTK_NOR_REG_DMA_DADR		0x720
>  #define MTK_NOR_REG_DMA_END_DADR	0x724
> +#define MTK_NOR_REG_DMA_DADR_HB		0x738
> +#define MTK_NOR_REG_DMA_END_DADR_HB	0x73c
>  
>  #define MTK_NOR_PRG_MAX_SIZE		6
>  // Reading DMA src/dst addresses have to be 16-byte aligned
> @@ -102,6 +104,7 @@ struct mtk_nor {
>  	unsigned int spi_freq;
>  	bool wbuf_en;
>  	bool has_irq;
> +	bool high_dma;
>  	struct completion op_done;
>  };
>  
> @@ -291,6 +294,11 @@ static int read_dma(struct mtk_nor *sp, u32 from, unsigned int length,
>  	writel(dma_addr, sp->base + MTK_NOR_REG_DMA_DADR);
>  	writel(dma_addr + length, sp->base + MTK_NOR_REG_DMA_END_DADR);
>  
> +	if (sp->high_dma) {
> +		writel(dma_addr >> 32, sp->base + MTK_NOR_REG_DMA_DADR_HB);
> +		writel((dma_addr + length) >> 32, sp->base + MTK_NOR_REG_DMA_END_DADR_HB);
> +	}
> +
>  	if (sp->has_irq) {
>  		reinit_completion(&sp->op_done);
>  		mtk_nor_rmw(sp, MTK_NOR_REG_IRQ_EN, MTK_NOR_IRQ_DMA, 0);
> @@ -594,7 +602,8 @@ static const struct spi_controller_mem_ops mtk_nor_mem_ops = {
>  };
>  
>  static const struct of_device_id mtk_nor_match[] = {
> -	{ .compatible = "mediatek,mt8173-nor" },
> +	{ .compatible = "mediatek,mt8192-nor", .data = (void *)36 },
> +	{ .compatible = "mediatek,mt8173-nor", .data = (void *)32 },
>  	{ /* sentinel */ }
>  };
>  MODULE_DEVICE_TABLE(of, mtk_nor_match);
> @@ -607,6 +616,7 @@ static int mtk_nor_probe(struct platform_device *pdev)
>  	u8 *buffer;
>  	struct clk *spi_clk, *ctlr_clk;
>  	int ret, irq;
> +	unsigned long dma_bits;
>  
>  	base = devm_platform_ioremap_resource(pdev, 0);
>  	if (IS_ERR(base))
> @@ -623,6 +633,13 @@ static int mtk_nor_probe(struct platform_device *pdev)
>  	buffer = devm_kmalloc(&pdev->dev,
>  			      MTK_NOR_BOUNCE_BUF_SIZE + MTK_NOR_DMA_ALIGN,
>  			      GFP_KERNEL);
> +
> +	dma_bits = (unsigned long)of_device_get_match_data(&pdev->dev);
> +	if (dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(dma_bits))) {
> +		dev_err(&pdev->dev, "failed to set dma mask(%lu)\n", dma_bits);
> +		return -EINVAL;
> +	}
> +

Do we need to set sp->high_dma when we have >32bits DMA?

Joe.C