On Sun, 7 Jun 2026 at 21:20, Simon Glass <[email protected]> wrote: > > Hi Ilias, > > On 2026-06-04T07:37:05, Ilias Apalodimas <[email protected]> wrote: > > doc: Add a warning about using RELOC_ADDR_TOP > > > > Since devices that can't DMA above 4GiB will misbehave with this option > > enabled add a warning on the documentation. > > > > Signed-off-by: Ilias Apalodimas <[email protected]> > > > > doc/develop/memory.rst | 6 ++++++ > > 1 file changed, 6 insertions(+) > > Reviewed-by: Simon Glass <[email protected]> > > nits/suggestions below > > > diff --git a/doc/develop/memory.rst b/doc/develop/memory.rst > > @@ -110,6 +110,12 @@ U-Boot Proper Flow > > > > This follows the same as in SPL flow. In board_init_f(), a part of > > memory > > is reserved at the end of RAM (see reserve_* functions in > > init_sequence_f) > > + #. Relocation address > > + By default U-Boot will try to relocate below the 4GiB boundary. If > > + RELOC_ADDR_TOP is enabled U-Boot will look into the dram bank config > > of > > + gd->dram[] and try to relocate to the highest available bank. Use > > this > > + with caution as devices that can only DMA below 4GiB will misbehave > > + since their buffers may be allocated above the 32-bit boundary. > > Can you check the rendering here? It seems that the title will run on > to the text? > > Also text only covers the default and RELOC_ADDR_TOP, but does not > mention that boards can still override via board_get_usable_ram_top(). > Worth a sentence, since that is the other half of the new behaviour > from patch 5.
Sure I'll update it on v6 Thanks /Ilias > > Regards, > Simon
