Re: [PATCH V2 13/19] csky: Library functions

[Arnd Bergmann]

On Sun, Jul 1, 2018 at 7:30 PM, Guo Ren <ren_guo@xxxxxxxxx> wrote:
>
> diff --git a/arch/csky/kernel/cskyksyms.c b/arch/csky/kernel/cskyksyms.c
> new file mode 100644
> index 0000000..3f13594
> --- /dev/null
> +++ b/arch/csky/kernel/cskyksyms.c
> @@ -0,0 +1,31 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
> +#include <linux/module.h>
> +#include <linux/uaccess.h>
> +#include <asm/cacheflush.h>
> +
> +/*
> + * Defined in libgcc
> + *
> + * See arch/csky/Makefile:
> + *     -print-libgcc-file-name
> + */
> +extern void __ashldi3 (void);
> +extern void __ashrdi3 (void);
> +extern void __lshrdi3 (void);
> +extern void __muldi3 (void);
> +extern void __ucmpdi2 (void);
> +EXPORT_SYMBOL(__ashldi3);
> +EXPORT_SYMBOL(__ashrdi3);
> +EXPORT_SYMBOL(__lshrdi3);
> +EXPORT_SYMBOL(__muldi3);
> +EXPORT_SYMBOL(__ucmpdi2);

It's better to avoid relying on libgcc here. Please use the
CONFIG_GENERIC_LIB_ASHLDI3/ASHRDI3/LSHRDI3/etc
helpers that we already have in the kernel.

       Arnd