Re: [Minios-devel] [PATCH v3 32/43] arm64: add the virtual address layout description

[Julien Grall <julien.grall@xxxxxxx>]

Hi,

On 16/04/18 07:32, Huang Shijie wrote:
> This patch describes the virtual address layout for 48bit arm64:
>    memory area (0xffff000000000000 ~ VIRT_KERNEL_AREA)   : used for linear 
> physical memory mapping
>    kernel area (VIRT_KERNEL_AREA   ~ VIRT_DEMAND_AREA)   : used for 
> map_frame_virt
>    demand area (VIRT_DEMAND_AREA   ~ VIRT_HEAP_AREA)     : used for ioremap
>    heap area   (VIRT_HEAP_AREA     ~ 0xffffffffffffffff) : used for heap
It would be better if the documentation is added where the macro where 
first defined. This would improve the understanding of the values.
Cheers,

> Signed-off-by: Huang Shijie <shijie.huang@xxxxxxx>
> ---
>   include/arm/arch_mm.h | 19 +++++++++++++++++++
>   1 file changed, 19 insertions(+)
>
> diff --git a/include/arm/arch_mm.h b/include/arm/arch_mm.h
> index 09a19c0..150259a 100644
> --- a/include/arm/arch_mm.h
> +++ b/include/arm/arch_mm.h
> @@ -9,6 +9,25 @@ typedef uint64_t paddr_t;
>   #define VIRT_DEMAND_AREA        (VIRT_KERNEL_AREA + MAX_MEM_SIZE)
>   #define VIRT_HEAP_AREA          (VIRT_DEMAND_AREA + MAX_MEM_SIZE)
>   
> +/*
> + * The virtual address layout for arm64(48bit):
> + *
> + *      
> --------------------------------------------------------------------------
> + *     |                                                                       
>    |
> + *      
> --------------------------------------------------------------------------
> + *     ^                   ^                   ^                 ^             
>    ^
> + *     |<-- memory area -->|<-- kernel area -->|<- demand area ->|<- heap area 
> -> |
> + *     ^
> + *     ^
> + *     |
> + * (0xffff000000000000, when TCR.T0SZ == 16)
> + *
> + * memory area (0xffff000000000000 ~ VIRT_KERNEL_AREA)   : used for linear 
> physical memory mapping
> + * kernel area (VIRT_KERNEL_AREA   ~ VIRT_DEMAND_AREA)   : used for 
> map_frame_virt
> + * demand area (VIRT_DEMAND_AREA   ~ VIRT_HEAP_AREA)     : used for ioremap
> + * heap area   (VIRT_HEAP_AREA     ~ 0xffffffffffffffff) : used for heap
> + */
> +
>   typedef uint64_t lpae_t;
>   
>   extern char _text, _etext, _erodata, _edata, _end, __bss_start;
--
Julien Grall

_______________________________________________
Minios-devel mailing list
Minios-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/minios-devel