Re: [PATCH 3/7] MIPS: fw: Record prom memory

[Serge Semin <fancer.lancer@gmail.com>]

On Thu, Aug 08, 2019 at 03:50:09PM +0800, Jiaxun Yang wrote:
> boot_mem_map is nolonger exist so we need to maintain a list
> of prom memory by ourselves.
> 
> Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
> ---
>  arch/mips/fw/arc/memory.c | 20 ++++++++++++++------
>  1 file changed, 14 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/mips/fw/arc/memory.c b/arch/mips/fw/arc/memory.c
> index 429b7f8d2aeb..02e954b3700e 100644
> --- a/arch/mips/fw/arc/memory.c
> +++ b/arch/mips/fw/arc/memory.c
> @@ -27,6 +27,11 @@
>  
>  #undef DEBUG
>  
> +#define MAX_PROM_MEM 5
> +static phys_addr_t prom_mem_base[MAX_PROM_MEM] __initdata;
> +static phys_addr_t prom_mem_size[MAX_PROM_MEM] __initdata;
> +static unsigned int nr_prom_mem __initdata;
> +
>  /*
>   * For ARC firmware memory functions the unit of meassuring memory is always
>   * a 4k page of memory
> @@ -129,6 +134,7 @@ void __init prom_meminit(void)
>  	}
>  #endif
>  
> +	nr_prom_mem = 0;
>  	p = PROM_NULL_MDESC;
>  	while ((p = ArcGetMemoryDescriptor(p))) {
>  		unsigned long base, size;
> @@ -139,6 +145,12 @@ void __init prom_meminit(void)
>  		type = prom_memtype_classify(p->type);
>  
>  		add_memory_region(base, size, type);
> +
> +		if (type == BOOT_MEM_ROM_DATA) {
> +			prom_mem_base[nr_prom_mem] = base;
> +			prom_mem_size[nr_prom_mem] = size;
> +			nr_prom_mem++;

Are you sure, that five prom-mem regions is enough? What about adding
a sanity check here so no to exceed the array size?

-Sergey

> +		}
>  	}
>  }
>  
> @@ -150,12 +162,8 @@ void __init prom_free_prom_memory(void)
>  	if (prom_flags & PROM_FLAG_DONT_FREE_TEMP)
>  		return;
>  
> -	for (i = 0; i < boot_mem_map.nr_map; i++) {
> -		if (boot_mem_map.map[i].type != BOOT_MEM_ROM_DATA)
> -			continue;
> -
> -		addr = boot_mem_map.map[i].addr;
> +	for (i = 0; i < nr_prom_mem; i++) {
>  		free_init_pages("prom memory",
> -				addr, addr + boot_mem_map.map[i].size);
> +			prom_mem_base[i], prom_mem_base[i] + prom_mem_size[i]);
>  	}
>  }
> -- 
> 2.22.0
>