[PATCH] airoha: rework RAM size handling to support multiple RAM size

[Mikhail Kshevetskiy]

On 22.07.2025 21:44, Christian Marangi wrote:
> There are multiple version of the same reference board with different
> RAM size and it's not enough to base the RAM size entirely from DT. To
> better support it use the get_ram_size way to scan for the actual RAM
> size of Airoha SoC and increase the size of the memory map.
>
> Signed-off-by: Christian Marangi <ansuelsmth at gmail.com>
> ---
>  arch/arm/mach-airoha/an7581/init.c | 23 +++++++++++++++++++----
>  1 file changed, 19 insertions(+), 4 deletions(-)
>
> diff --git a/arch/arm/mach-airoha/an7581/init.c b/arch/arm/mach-airoha/an7581/init.c
> index d149e0ee3c8..0f72365c4ab 100644
> --- a/arch/arm/mach-airoha/an7581/init.c
> +++ b/arch/arm/mach-airoha/an7581/init.c
> @@ -2,10 +2,14 @@
>  
>  #include <fdtdec.h>
>  #include <init.h>
> +#include <linux/sizes.h>
>  #include <sysreset.h>
>  #include <asm/armv8/mmu.h>
> +#include <asm/global_data.h>
>  #include <asm/system.h>
>  
> +DECLARE_GLOBAL_DATA_PTR;
> +
>  int print_cpuinfo(void)
>  {
>  	printf("CPU:   Airoha AN7581\n");
> @@ -14,12 +18,23 @@ int print_cpuinfo(void)
>  
>  int dram_init(void)
>  {
> -	return fdtdec_setup_mem_size_base();
> +	int ret;
> +
> +	ret = fdtdec_setup_mem_size_base();
> +	if (ret)
> +		return ret;
> +
> +	gd->ram_size = get_ram_size((void *)gd->ram_base, SZ_8G);

Can we use a memory size passed by airoha trusted firmware instead of
playing with  get_ram_size()?

> +
> +	return 0;
>  }
>  
>  int dram_init_banksize(void)
>  {
> -	return fdtdec_setup_memory_banksize();
> +	gd->bd->bi_dram[0].start = gd->ram_base;
> +	gd->bd->bi_dram[0].size = gd->ram_size;
as I know u-boot can safely use only 2Gb of memory, thus it's better

        #define CFG_MAX_MEM_MAPPED  SZ_2G

and replace above line with

        gd->bd->bi_dram[0].size = get_effective_memsize();

> +
> +	return 0;
>  }
>  
>  void reset_cpu(void)
> @@ -32,12 +47,12 @@ static struct mm_region an7581_mem_map[] = {
>  		/* DDR */
>  		.virt = 0x80000000UL,
>  		.phys = 0x80000000UL,
> -		.size = 0x80000000UL,
> +		.size = 0x200000000ULL,
>  		.attrs = PTE_BLOCK_MEMTYPE(MT_NORMAL) | PTE_BLOCK_OUTER_SHARE,
>  	}, {
>  		.virt = 0x00000000UL,
>  		.phys = 0x00000000UL,
> -		.size = 0x20000000UL,
> +		.size = 0x40000000UL,
>  		.attrs = PTE_BLOCK_MEMTYPE(MT_DEVICE_NGNRNE) |
>  			 PTE_BLOCK_NON_SHARE |
>  			 PTE_BLOCK_PXN | PTE_BLOCK_UXN