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

From: Yingjoe Chen
Date: Sat Sep 19 2020 - 11:32:02 EST


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@xxxxxxxxxxxx>
> ---
>
> (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