Date:   Tue, 11 Jan 2022 09:28:05 -0800 (PST)
Subject:     Re: [PATCH] riscv: mm: fix wrong phys_ram_base value for RV64
In-Reply-To: <20211202153641.1961-1-jszhang@kernel.org>
CC:     Paul Walmsley <paul.walmsley@sifive.com>, aou@eecs.berkeley.edu,
        alex@ghiti.fr, linux-riscv@lists.infradead.org,
        linux-kernel@vger.kernel.org
From:   Palmer Dabbelt <palmer@dabbelt.com>
To:     jszhang@kernel.org
Message-ID: <mhng-662897d8-3b0a-4580-a607-f853c01263b5@palmer-ri-x1c9>
Mime-Version: 1.0 (MHng)
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On Thu, 02 Dec 2021 07:36:41 PST (-0800), jszhang@kernel.org wrote:
> Currently, if 64BIT and !XIP_KERNEL, the phys_ram_base is always 0,
> no matter the real start of dram reported by memblock is. The original
> patch[1] is correct, I believe it's not corrected merged due to lots
> of #ifdef in arch/riscv/mm/init.c, I plan to send a clean up series
> soon.
>
> [1] http://lists.infradead.org/pipermail/linux-riscv/2021-July/007650.html
>
> Fixes: 6d7f91d914bc ("riscv: Get rid of CONFIG_PHYS_RAM_BASE in kernel physical address conversion")
> Signed-off-by: Jisheng Zhang <jszhang@kernel.org>

Thanks, this is on for-next.

> ---
>  arch/riscv/mm/init.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> index 24b2b8044602..3c0649dba4ff 100644
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@ -187,10 +187,10 @@ static void __init setup_bootmem(void)
>
>
>  	phys_ram_end = memblock_end_of_DRAM();
> -#ifndef CONFIG_64BIT
>  #ifndef CONFIG_XIP_KERNEL
>  	phys_ram_base = memblock_start_of_DRAM();
>  #endif
> +#ifndef CONFIG_64BIT
>  	/*
>  	 * memblock allocator is not aware of the fact that last 4K bytes of
>  	 * the addressable memory can not be mapped because of IS_ERR_VALUE