Re: [PATCH 5/6] tty: Add SBI debug console support to HVC SBI driver

Greg Kroah-Hartman
2023-10-10T17:12:57Z

On Tue, Oct 10, 2023 at 10:35:02PM +0530, Anup Patel wrote:
> --- a/drivers/tty/hvc/hvc_riscv_sbi.c
> +++ b/drivers/tty/hvc/hvc_riscv_sbi.c
> @@ -15,6 +15,7 @@
>
> #include "hvc_console.h"
>
> +#ifdef CONFIG_RISCV_SBI_V01

Please no #ifdef in a .c file, that's not a good style for Linux code at
all.

And what if you want to build the driver for both options here? What
will happen?

> +static int hvc_sbi_dbcn_tty_put(uint32_t vtermno, const char *buf, int count)
> {
> - return PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_ops, 16));
> + phys_addr_t pa;
> + struct sbiret ret;
> +
> + if (is_vmalloc_addr(buf))
> + pa = page_to_phys(vmalloc_to_page(buf)) + offset_in_page(buf);
> + else
> + pa = __pa(buf);
> +
> + ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_WRITE,
> +#ifdef CONFIG_32BIT
> + count, pa, (u64)pa >> 32,
> +#else
> + count, pa, 0,
> +#endif

This is not how to do an api, sorry, again, please no #ifdef if you want
to support this code for the next 20+ years.

thanks,

gre gk-h