[U-Boot] [PATCH 1/3] riscv: Add asm/dma-mapping.h for DMA mappings

[Bin Meng <bmeng.cn@gmail.com>]

On Mon, Dec 17, 2018 at 7:52 PM Anup Patel <anup@brainfault.org> wrote:
>
> From: Anup Patel <anup.patel@wdc.com>
>
> This patch adds asm/dma-mapping.h for Linux-like DMA mappings
> APIs required by some of the drivers (such as, Cadance MACB
> Ethernet driver).
>
> Signed-off-by: Anup Patel <anup.patel@wdc.com>
> ---
>  arch/riscv/include/asm/dma-mapping.h | 37 ++++++++++++++++++++++++++++
>  1 file changed, 37 insertions(+)
>  create mode 100644 arch/riscv/include/asm/dma-mapping.h
>

Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

But please see nits below:

> diff --git a/arch/riscv/include/asm/dma-mapping.h b/arch/riscv/include/asm/dma-mapping.h
> new file mode 100644
> index 0000000000..9782b6f168
> --- /dev/null
> +++ b/arch/riscv/include/asm/dma-mapping.h
> @@ -0,0 +1,37 @@
> +/* SPDX-License-Identifier: GPL-2.0+ */
> +/*
> + * Copyright (c) 2018 Western Digital Corporation or its affiliates.
> + *
> + * Authors:
> + *   Anup Patel <anup.patel@wdc.com>
> + */

nits: should have one blank line here

> +#ifndef __ASM_RISCV_DMA_MAPPING_H
> +#define __ASM_RISCV_DMA_MAPPING_H
> +
> +#include <linux/dma-direction.h>
> +
> +#define        dma_mapping_error(x, y) 0

nits: no <tab> between #define and dma_

> +
> +static inline void *dma_alloc_coherent(size_t len, unsigned long *handle)
> +{
> +       *handle = (unsigned long)memalign(ARCH_DMA_MINALIGN, len);
> +       return (void *)*handle;
> +}
> +
> +static inline void dma_free_coherent(void *addr)
> +{
> +       free(addr);
> +}
> +
> +static inline unsigned long dma_map_single(volatile void *vaddr, size_t len,
> +                                          enum dma_data_direction dir)
> +{
> +       return (unsigned long)vaddr;
> +}
> +
> +static inline void dma_unmap_single(volatile void *vaddr, size_t len,
> +                                   unsigned long paddr)
> +{
> +}
> +
> +#endif /* __ASM_RISCV_DMA_MAPPING_H */
> --

Regards,
Bin