The VideoCore mailbox GET_ARM_MEMORY only reports the size of the first accessible memory region (~947 MiB on RPi4 with 8GB), not the total RAM. This causes U-Boot to display "DRAM: 947 MiB (total 7.9 GiB)" instead of "DRAM: 7.9 GiB".
On Raspberry Pi 4 with 8GB RAM, the memory is split across multiple non-contiguous banks. The dram_init() function only sets gd->ram_size to the first bank size reported by the VideoCore firmware, while fdtdec_setup_memory_banksize() correctly populates all memory banks from the device tree. Fix this by updating gd->ram_size after dram_init_banksize() has populated all memory banks, so it reflects the actual total RAM across all banks. Signed-off-by: Anders Roxell <[email protected]> --- board/raspberrypi/rpi/rpi.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/board/raspberrypi/rpi/rpi.c b/board/raspberrypi/rpi/rpi.c index 1b0b664fa2b7..0cd45104b3bc 100644 --- a/board/raspberrypi/rpi/rpi.c +++ b/board/raspberrypi/rpi/rpi.c @@ -332,13 +332,27 @@ int dram_init(void) #ifdef CONFIG_OF_BOARD int dram_init_banksize(void) { + phys_addr_t total_size = 0; + int i; int ret; ret = fdtdec_setup_memory_banksize(); if (ret) return ret; - return fdtdec_setup_mem_size_base(); + ret = fdtdec_setup_mem_size_base(); + if (ret) + return ret; + + /* Update gd->ram_size to reflect total RAM across all banks */ + for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) { + if (gd->bd->bi_dram[i].size == 0) + break; + total_size += gd->bd->bi_dram[i].size; + } + gd->ram_size = total_size; + + return 0; } #endif -- 2.51.0
