Hi Marek, On Fri, 5 Jun 2026 at 01:34, Marek Vasut <[email protected]> wrote: > > On 6/4/26 9:37 AM, Ilias Apalodimas wrote: > > Currently, the bi_dram[] information is stored in the board info > > structure (bd). Because bd is only valid after reserve_board(), > > dram_init_banksize() must be called late in the initialization process. > > This limitation is problematic, as it forces us to rely on a variety of > > bespoke functions to determine board RAM, bank memory sizes, and other > > early setup requirements. > > > > By moving bi_dram[] into the global data (gd), we can run it earlier. > > This is particularly convenient since boards define their own > > dram_init_banksize() routines, which do not always rely on parsing > > Device Tree (DT) memory nodes. > > > > Additionally, U-Boot defaults to relocating to the top of the first memory > > bank. While boards currently use custom functions to override this > > behavior, having the DRAM bank information available earlier in gd makes > > relocating to a different bank trivial and standardizes the process. > Regarding the BD, this is likely really old, but it seems BD might be > passed from U-Boot to Linux somehow ? See [1] and U-Boot > include/asm-generic/u-boot.h : > > 8 * NOTE: This header file defines an interface to U-Boot. Including > 9 * this (unmodified) header file in another file is considered normal > 10 * use of U-Boot, and does *not* fall under the heading of "derived > 11 * work". > > Are we certain we are not breaking ABI here ?
That's a good point and I did look at U-Boot briefly when I changed the location. However, I didn't look at the kernel... Unfortunately, I don't have a platform I can test. Let's see if Tom's CC helps. Thanks /Ilias > > [1] > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/powerpc/boot/ppcboot.h >
