Re: [PATCH 4/6] MIPS: Loongson64: Add 2K1000 early_printk_port

From: Jiaxun Yang
Date: Wed Feb 10 2021 - 06:29:43 EST




On Tue, Feb 9, 2021, at 5:32 PM, Qing Zhang wrote:
> Distinguish between 3A series CPU and 2K1000 CPU UART0.
>
> Signed-off-by: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>
> Signed-off-by: Qing Zhang <zhangqing@xxxxxxxxxxx>
> Signed-off-by: Xingxing Su <suxingxing@xxxxxxxxxxx>

Personally I don't like this kind of quirk.
Probably we should use earlycon as Arm later.

- Jiaxun

> ---
> arch/mips/loongson64/init.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/arch/mips/loongson64/init.c b/arch/mips/loongson64/init.c
> index 8bef1ebab72d..a8ad02d8d088 100644
> --- a/arch/mips/loongson64/init.c
> +++ b/arch/mips/loongson64/init.c
> @@ -120,7 +120,10 @@ void __init prom_init(void)
> #endif
>
> /* Hardcode to CPU UART 0 */
> - setup_8250_early_printk_port(TO_UNCAC(LOONGSON_REG_BASE + 0x1e0), 0, 1024);
> + if ((read_c0_prid() & PRID_IMP_MASK) == PRID_IMP_LOONGSON_64R)
> + setup_8250_early_printk_port(TO_UNCAC(LOONGSON_REG_BASE), 0, 1024);
> + else
> + setup_8250_early_printk_port(TO_UNCAC(LOONGSON_REG_BASE + 0x1e0), 0, 1024);
>
> register_smp_ops(&loongson3_smp_ops);
> board_nmi_handler_setup = mips_nmi_setup;
> --
> 2.20.1
>
>

--
- Jiaxun