u-boot hard fault error after ram initialization

Question

I have ported U-boot on my Waveshare coreH7 stm32h743 board. I have used stm32h743-disco files and device trees as a template for porting. my onboard SDRAM is IS42S16400J that is 8MBytes. I have calculate the parameters of my sdram and I put them in my board device tree file as shown as below:

/*
             * Memory configuration from sdram datasheet IS42S32800G-6BLI
             * firsct bank is bank@0
             * second bank is bank@1
             */
            bank2: bank@1 {
                st,sdram-control = /bits/ 8 <NO_COL_8
                                 NO_ROW_12
                                 MWIDTH_16
                                 BANKS_4
                                 CAS_3
                                 SDCLK_2
                                 RD_BURST_EN
                                 RD_PIPE_DL_0>;
                st,sdram-timing = /bits/ 8 <TMRD_1
                                TXSR_1
                                TRAS_1
                                TRC_6
                                TRP_2
                                TWR_1
                                TRCD_1>;
                st,sdram-refcount = <300>;
            };

also, I have been configured the rcc values to feed the dram with 100MHz.

but when uboot starts initialization, it goes to hard fault interrupt.

this is the log:

lib/fdtdec.c:fdtdec_setup_mem_size_base_fdt() fdtdec_setup_mem_size_base_fdt: Initial DRAM size 2000000
include/initcall.h:initcall_run_list() initcall: 08008a89
common/board_f.c:setup_dest_addr() Monitor len: 00039F80
common/board_f.c:setup_dest_addr() Ram size: 02000000
common/board_f.c:setup_dest_addr() Ram top: D2000000
include/initcall.h:initcall_run_list() initcall: 08008665
include/initcall.h:initcall_run_list() initcall: 0800117d
arch/arm/lib/cache.c:arm_reserve_mmu() TLB table from d1ff0000 to d1ff4000
include/initcall.h:initcall_run_list() initcall: 080088c3
include/initcall.h:initcall_run_list() initcall: 080088c7
include/initcall.h:initcall_run_list() initcall: 080086b1
common/board_f.c:reserve_uboot() Reserving 231k for U-Boot at: d1fb6000
include/initcall.h:initcall_run_list() initcall: 080088ed
common/board_f.c:reserve_malloc() Reserving 1032k for malloc() at: d1eb4000
include/initcall.h:initcall_run_list() initcall: 08008821
Hard fault
pc : 0800087e    lr : 00000000    xPSR : 21000000
r12 : d1eb3ff0   r3 : 00000000    r2 : 00000010
r1 : 00000000    r0 : d1eb3fb0
Resetting CPU ...

what is the problem? is ram initialized unsuccessfully? why? maybe wrong parameters? how Can I know that ram is initialized successfully? this is normal info log of u-boot:

U-Boot 2020.07-00610-g610e1487c8-dirty (Aug 04 2020 - 00:34:13 +0430)

Model: Waveshare STM32H743i-Coreh7 board
DRAM:  Hard fault
pc : 0800087e    lr : 00000000    xPSR : 21000000
r12 : d1eb3ff0   r3 : 00000000    r2 : 00000010
r1 : 00000000    r0 : d1eb3fb0
Resetting CPU ...

Answer 1

your ram size is wrong. as you mentioned, the actual ram size is 8MB that is 0x7A1200 in hexadecimal number. but in U-boot log is "Initial DRAM size 2000000". you should change it in the device tree of your board.

memory {
      device_type = "memory";
      reg = <0xd0000000 0x7A1200>;
};