[PATCH v7 0/7] Relocate U-Boot in the last bank

[Jonas Karlman]

Hi,

On 6/25/2026 5:18 PM, Tom Rini wrote:
> On Wed, 17 Jun 2026 10:48:18 +0300, Ilias Apalodimas wrote:
> 
>> There was a discussion recently on the mailing lists regarding our
>> management of memory above ram_top [0]. The tl;dr is that we have two problems.
>>
>> The first one is that U-Boot always relocates to the top of the first available
>> bank unless there's special board code to sidestep that. The second is we don't
>> successfully deal with devices that can only do 32-bit DMA.
>>
>> [...]
> 
> Applied to u-boot/next, thanks!
> 
> [1/7] treewide: move bi_dram[] from bd to gd
>       commit: 1174c99ab421168221be372bd83a4143bf5f167d
> [2/7] common: move ram_base calculation to independent INITCALL()
>       commit: 15b35e4289e11f1ab201701dfb6dc0232b30be48
> [3/7] common: Clean up setup_dest_addr()
>       commit: 0943f107ce4adb47d4b01c06e046dce130a1de50
> [4/7] rpi: Add a local get_effective_memsize()
>       commit: d19d9e1c064b6c782959d1da7bddf1e9da1c55d4
> [5/7] common: Add an option to relocate on ram top
>       commit: 55a34217698491cc0bb8d53d630644dc8756629c

Ilias pointed out on IRC that Rockchip boards may have been affected by
this series now being merged, and where correct.

The move of dram_init_banksize() before setup_ram_config() currently
breaks Rockchip boards in next, due to gd->ram_top now being 0 when
Rockchip variant of dram_init_banksize() is called.

DRAM banks on a RK3568 8 GiB board (RK ATAGS not used) using next:

  DRAM bank   = 0x0000000000000000
  -> start    = 0x0000000000200000
  -> size     = 0xffffffffffe00000
  DRAM bank   = 0x0000000000000001
  -> start    = 0x0000000100000000
  -> size     = 0x0000000100000000

expected banks prior to this merge:

  DRAM bank   = 0x0000000000000000
  -> start    = 0x0000000000200000
  -> size     = 0x00000000efe00000
  DRAM bank   = 0x0000000000000001
  -> start    = 0x0000000100000000
  -> size     = 0x0000000100000000

'out of memory' errors are also reported because of the bad bank size:

  Core:  632 devices, 33 uclasses, devicetree: separate
  out of memory
  ERROR: Out of memory
  MMC:   mmc at fe2b0000: 1, mmc at fe310000: 0

I am also seeing following, not sure it is related or a different issue:

  ERROR: reserving fdt memory region failed (addr=10f000 size=100 flags=2): -22

Current logic in dram_init_banksize() require the final gd->ram_top to
fully function, hopefully we can find a workaround or try to rework the
affected code instead of having to do a partial revert.

Regards,
Jonas

> [6/7] configs: Enable RELOC_ADDR_TOP on arm64 QEMU
>       commit: aefd4a769bb6727978c408ff24b93ba9047d535d
> [7/7] doc: Add a warning about using RELOC_ADDR_TOP
>       commit: fb537c85bca0e3d29a62fe119181bf1744b8c91a