[PATCH] arm64: versal2: Populate DRAM banks before page table size calculation

[Michal Simek]

On 12/9/25 15:43, Tom Rini wrote:
> On Tue, Dec 09, 2025 at 03:17:45PM +0100, Michal Simek wrote:
> 
>> From: Pranav Sanwal <pranav.sanwal at amd.com>
>>
>> Move DRAM bank detection from fdtdec to custom implementation to
>> ensure memory banks are populated before get_page_table_size() is
>> called during MMU initialization.
>>
>> The current fdtdec-based approach populates gd->bd->bi_dram[] too
>> late in the boot sequence, causing get_page_table_size() to be
>> called with unpopulated DRAM information. This prevents dynamic
>> page table sizing based on actual memory configuration.
>>
>> Parse /memory nodes in dram_init() to fill versal2_mem_map[]
>> early enough for MMU setup. Supports up to
>> CONFIG_NR_DRAM_BANKS (36) non-contiguous banks with high memory
>> regions (>4GB) and use __weak get_page_table_size implementation
>> to estimate page table size based on the populated DRAM banks.
>>
>> Signed-off-by: Pranav Sanwal <pranav.sanwal at amd.com>
>> Signed-off-by: Michal Simek <michal.simek at amd.com>
> [snip]
>> diff --git a/include/dm/ofnode.h b/include/dm/ofnode.h
>> index 120393426dbf..5be9513f5238 100644
>> --- a/include/dm/ofnode.h
>> +++ b/include/dm/ofnode.h
>> @@ -1886,4 +1886,6 @@ int ofnode_copy_node(ofnode dst_parent, const char *name, ofnode src,
>>    */
>>   int ofnode_delete(ofnode *nodep);
>>   
>> +ofnode get_next_memory_node(ofnode mem);
> 
> This function is in lib/fdtdec.c and so we should have the declaration
> in include/fdtdec.h and while it doesn't have a kernel-doc comment
> today, it should. If you want to in v2 make 1/2 add the prototype and
> comment and 2/2 use it in mach-versal that might be a good split.

We will do. And do you have any issue with logic in this patch?
Pretty much we don't want u-boot to be relocated inside the memory bank where it 
was initially loaded and we didn't find a better way to do it.

Thanks,
Michal