[U-Boot] [PATCH v2 1/6] x86: Support machines with >4GB of RAM

[Lukasz Majewski]

Hi Simon,

> Some systems have more than 4GB of RAM. U-Boot can only place things
> below 4GB so any memory above that should not be used. Ignore any
> such memory so that the memory size will not exceed the maximum.
> 
> This prevents gd->ram_size exceeding 4GB which causes problems for PCI
> devices which use DMA.
> 
> Signed-off-by: Simon Glass <sjg at chromium.org>
> Reviewed-by: Bin Meng <bmeng.cn at gmail.com>
> ---
> 
> Changes in v2: None
> 
>  arch/x86/cpu/coreboot/sdram.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/x86/cpu/coreboot/sdram.c
> b/arch/x86/cpu/coreboot/sdram.c index e98a230..9c3ab81 100644
> --- a/arch/x86/cpu/coreboot/sdram.c
> +++ b/arch/x86/cpu/coreboot/sdram.c
> @@ -90,7 +90,8 @@ int dram_init(void)
>  		struct memrange *memrange = &lib_sysinfo.memrange[i];
>  		unsigned long long end = memrange->base +
> memrange->size; 
> -		if (memrange->type == CB_MEM_RAM && end > ram_size)
> +		if (memrange->type == CB_MEM_RAM && end > ram_size &&
> +		    memrange->base < (1ULL << 32))
>  			ram_size = end;
>  	}
>  	gd->ram_size = ram_size;
> @@ -108,7 +109,8 @@ void dram_init_banksize(void)
>  		for (i = 0, j = 0; i < lib_sysinfo.n_memranges; i++)
> { struct memrange *memrange = &lib_sysinfo.memrange[i];
>  
> -			if (memrange->type == CB_MEM_RAM) {
> +			if (memrange->type == CB_MEM_RAM &&
> +			    memrange->base < (1ULL << 32)) {
>  				gd->bd->bi_dram[j].start =
> memrange->base; gd->bd->bi_dram[j].size = memrange->size;
>  				j++;

Reviewed-by: Lukasz Majewski <l.majewski at samsung.com>

-- 
Best regards,

Lukasz Majewski

Samsung R&D Institute Poland (SRPOL) | Linux Platform Group