Subject: [PATCH v4 6/7] arm64: mm: Implement 4 levels of translation tables

From: [email-masked] (Catalin Marinas)
Date: Tue, 29 Apr 2014 18:04:04 +0100

On Tue, Apr 29, 2014 at 05:59:33AM +0100, Jungseok Lee wrote:
> diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
> index 0fd5650..03ec424 100644
> --- a/arch/arm64/kernel/head.S
> +++ b/arch/arm64/kernel/head.S
> @@ -37,8 +37,9 @@
> 
>  /*
>   * swapper_pg_dir is the virtual address of the initial page table. We place
> - * the page tables 3 * PAGE_SIZE below KERNEL_RAM_VADDR. The idmap_pg_dir has
> - * 2 pages and is placed below swapper_pg_dir.
> + * the page tables 3 * PAGE_SIZE (2 or 3 levels) or 4 * PAGE_SIZE (4 levels)
> + * below KERNEL_RAM_VADDR. The idmap_pg_dir has 2 pages (2 or 3 levels) or
> + * 3 pages (4 levels) and is placed below swapper_pg_dir.
>   */
>  #define KERNEL_RAM_VADDR       (PAGE_OFFSET + TEXT_OFFSET)
> 
> @@ -46,8 +47,13 @@
>  #error KERNEL_RAM_VADDR must start at 0xXXX80000
>  #endif
> 
> +#ifdef CONFIG_ARM64_4_LEVELS
> +#define SWAPPER_DIR_SIZE       (4 * PAGE_SIZE)
> +#define IDMAP_DIR_SIZE         (3 * PAGE_SIZE)
> +#else
>  #define SWAPPER_DIR_SIZE       (3 * PAGE_SIZE)
>  #define IDMAP_DIR_SIZE         (2 * PAGE_SIZE)
> +#endif

Mark Rutland was doing some clean-up of this code to no longer place
swapper_pg_dir and idmap_pg_dir below the kernel image. I'm not sure
whether the patches ended up on the list yet (not a problem for now,
just a slight change for your patches).

-- 
Catalin