On Tue, 5 Dec 2017 17:47:14 +0900
Masahiro Yamada <yamada.masah...@socionext.com> wrote:
> This driver is the last/only user of NAND_OWN_BUFFERS. Boris suggested
> to remove this flag.
>
> Taking a closer look at this driver, it calls dma_alloc_coherent() for
> the concatenated area for the DMA bounce buffer + struct nand_buffers,
> but the latter does not need to be DMA-coherent; cafe_{write,read}_buf
> simply do memcpy() between buffers when usedma==1.
>
> Let's do dma_alloc_coherent() for the DMA bounce buffer in the front,
> and leave the nand_buffers allocation to nand_scan_tail(), then rip off
> NAND_OWN_BUFFERS.
>
> The magic number, 2112, is still mysterious (hard-coded writesize +
> oobsize ?), but this is not our main interest. I am keeping it.
>
> Suggested-by: Boris Brezillon <boris.brezil...@free-electrons.com>
> Signed-off-by: Masahiro Yamada <yamada.masah...@socionext.com>
Applied the whole series.
Thanks,
Boris
> ---
>
> Changes in v2:
> - Newly added
>
> drivers/mtd/nand/cafe_nand.c | 24 ++++--------------------
> 1 file changed, 4 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/mtd/nand/cafe_nand.c b/drivers/mtd/nand/cafe_nand.c
> index bc558c4..add4613 100644
> --- a/drivers/mtd/nand/cafe_nand.c
> +++ b/drivers/mtd/nand/cafe_nand.c
> @@ -613,7 +613,6 @@ static int cafe_nand_probe(struct pci_dev *pdev,
> uint32_t ctrl;
> int err = 0;
> int old_dma;
> - struct nand_buffers *nbuf;
>
> /* Very old versions shared the same PCI ident for all three
> functions on the chip. Verify the class too... */
> @@ -661,7 +660,6 @@ static int cafe_nand_probe(struct pci_dev *pdev,
>
> /* Enable the following for a flash based bad block table */
> cafe->nand.bbt_options = NAND_BBT_USE_FLASH;
> - cafe->nand.options = NAND_OWN_BUFFERS;
>
> if (skipbbt) {
> cafe->nand.options |= NAND_SKIP_BBTSCAN;
> @@ -731,15 +729,12 @@ static int cafe_nand_probe(struct pci_dev *pdev,
> if (err)
> goto out_irq;
>
> - cafe->dmabuf = dma_alloc_coherent(&cafe->pdev->dev,
> - 2112 + sizeof(struct nand_buffers) +
> - mtd->writesize + mtd->oobsize,
> - &cafe->dmaaddr, GFP_KERNEL);
> + cafe->dmabuf = dma_alloc_coherent(&cafe->pdev->dev, 2112,
> + &cafe->dmaaddr, GFP_KERNEL);
> if (!cafe->dmabuf) {
> err = -ENOMEM;
> goto out_irq;
> }
> - cafe->nand.buffers = nbuf = (void *)cafe->dmabuf + 2112;
>
> /* Set up DMA address */
> cafe_writel(cafe, cafe->dmaaddr & 0xffffffff, NAND_DMA_ADDR0);
> @@ -752,11 +747,6 @@ static int cafe_nand_probe(struct pci_dev *pdev,
> cafe_dev_dbg(&cafe->pdev->dev, "Set DMA address to %x (virt %p)\n",
> cafe_readl(cafe, NAND_DMA_ADDR0), cafe->dmabuf);
>
> - /* this driver does not need the @ecccalc and @ecccode */
> - nbuf->ecccalc = NULL;
> - nbuf->ecccode = NULL;
> - nbuf->databuf = (uint8_t *)(nbuf + 1);
> -
> /* Restore the DMA flag */
> usedma = old_dma;
>
> @@ -801,10 +791,7 @@ static int cafe_nand_probe(struct pci_dev *pdev,
> goto out;
>
> out_free_dma:
> - dma_free_coherent(&cafe->pdev->dev,
> - 2112 + sizeof(struct nand_buffers) +
> - mtd->writesize + mtd->oobsize,
> - cafe->dmabuf, cafe->dmaaddr);
> + dma_free_coherent(&cafe->pdev->dev, 2112, cafe->dmabuf, cafe->dmaaddr);
> out_irq:
> /* Disable NAND IRQ in global IRQ mask register */
> cafe_writel(cafe, ~1 & cafe_readl(cafe, GLOBAL_IRQ_MASK),
> GLOBAL_IRQ_MASK);
> @@ -829,10 +816,7 @@ static void cafe_nand_remove(struct pci_dev *pdev)
> nand_release(mtd);
> free_rs(cafe->rs);
> pci_iounmap(pdev, cafe->mmio);
> - dma_free_coherent(&cafe->pdev->dev,
> - 2112 + sizeof(struct nand_buffers) +
> - mtd->writesize + mtd->oobsize,
> - cafe->dmabuf, cafe->dmaaddr);
> + dma_free_coherent(&cafe->pdev->dev, 2112, cafe->dmabuf, cafe->dmaaddr);
> kfree(cafe);
> }
>
