- * In the context of SPL, board_init_f must ensure that any clocks/etc for
- * DDR are enabled, ensure that the stack pointer is valid, clear the BSS
- * and call board_init_f. We provide this version by default but mark it
- * as __weak to allow for platforms to do this in their own way if needed.
+ * In the context of SPL, board_init_f() prepares the hardware for execution
+ * from system RAM (DRAM, DDR...). As system RAM may not be available yet,
+ * board_init_f() must use the current GD to store any data which must be
+ * passed on to later stages. These data include the relocation destination,
+ * the future stack, and the future GD location. BSS is cleared after this
+ * function (and therefore must be accessible).
+ *
+ * We provide this version by default but mark it as __weak to allow for
+ * platforms to do this in their own way if needed. Please see the top
+ * level U-Boot README "Board Initialization Flow" section for info on what
+ * to put in this function.