Re: [PATCH] MIPS: ath79: reduce ARCH_DMA_MINALIGN

[Thomas Bogendoerfer]

On Wed, May 27, 2026 at 03:25:04PM -0700, Rosen Penev wrote:
> Currently, ath79 SoCs use the default ARCH_DMA_MINALIGN value of 128
> bytes defined in mach-generic. This is excessive for these platforms
> and leads to significant memory waste in kmalloc.
> 
> Override ARCH_DMA_MINALIGN to use L1_CACHE_BYTES, which is 32 bytes for
> ath79 SoCs.
> 
> Signed-off-by: Rosen Penev <rosenp@xxxxxxxxx>
> ---
>  arch/mips/include/asm/mach-ath79/kmalloc.h | 7 +++++++
>  1 file changed, 7 insertions(+)
>  create mode 100644 arch/mips/include/asm/mach-ath79/kmalloc.h
> 
> diff --git a/arch/mips/include/asm/mach-ath79/kmalloc.h b/arch/mips/include/asm/mach-ath79/kmalloc.h
> new file mode 100644
> index 000000000000..954f5d6e0dd0
> --- /dev/null
> +++ b/arch/mips/include/asm/mach-ath79/kmalloc.h
> @@ -0,0 +1,7 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#ifndef __ASM_MACH_ATH79_KMALLOC_H
> +#define __ASM_MACH_ATH79_KMALLOC_H
> +
> +#define ARCH_DMA_MINALIGN	L1_CACHE_BYTES
> +
> +#endif /* __ASM_MACH_ATH79_KMALLOC_H */
> -- 
> 2.54.0

applied to mips-next

Thomas.

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