I have a tablet with 1Gb of ram (two chips),but not u-boot neither kernel detect it (only 512Mb).

Does i need to change something in arch/arm/mach-sunxi/dram_sun8i_a33.c ?

i posta alettronica found this struct in sunxi_dram_init(void) function:

struct dram_para para = { .cs1 = 0, .bank = 1, .rank = 1, .rows = 15, .bus_width = 16, .page_size = 2048, };

Thanks