zephyr stuck in HAL LTDC initializing process

[Dictor]

I'm working on nucleo-h743zi board and Hope to test some DAC for display which fit with LTDC's interface. However always zephyr is stucked in below code and everything is work normally when disabling LTDC.

reproducing situation

This can be reproduce on zephyr's default hello_world example with adding below two configurations. Every other thing is same with hello_world's

prj.conf

CONFIG_DISPLAY=y
CONFIG_STM32_LTDC=y

app.overay

&ltdc {
    status = "okay";
    // RGB565 interface
    pinctrl-0 = <
        &ltdc_r3_pb0
        &ltdc_r4_pa5
        &ltdc_r5_pc0
        &ltdc_r6_pb1
        &ltdc_r7_pe15
        &ltdc_g2_pa6
        &ltdc_g3_pe11
        &ltdc_g4_pb10
        &ltdc_g5_pb11
        &ltdc_g6_pc7
        &ltdc_g7_pg8
        &ltdc_b3_pd10
        &ltdc_b4_pe12
        &ltdc_b5_pa3
        &ltdc_b6_pb8
        &ltdc_b7_pb9
        &ltdc_de_pf10
        &ltdc_clk_pe14
        &ltdc_hsync_pc6
        &ltdc_vsync_pa4
    >;
    pinctrl-names = "default";
    // from ADV7123(GM7123)'s spec
    hsync-pol = <STM32_LTDC_HSPOL_ACTIVE_LOW>;
    vsync-pol = <STM32_LTDC_VSPOL_ACTIVE_LOW>;
    de-pol = <STM32_LTDC_DEPOL_ACTIVE_LOW>;
    pclk-pol = <STM32_LTDC_PCPOL_ACTIVE_HIGH>;
    // from VGA timing of 320x200,60Hz
    hsync-duration = <32>;
    vsync-duration = <6>;
    hfp-duration = <8>;
     hbp-duration = <40>;
    vfp-duration = <3>;
    vbp-duration = <6>;
    height = <200>;
    width = <320>;
};

build & debug logs

Linker's log says frame buffer successfully placed on SRAM.

[12/12] Linking C executable zephyr\zephyr.elf
Memory region         Used Size  Region Size  %age Used
           FLASH:       17252 B         2 MB      0.82%
            SRAM:      132608 B       512 KB     25.29%
     BACKUP_SRAM:          0 GB         4 KB      0.00%
           SRAM1:          0 GB       128 KB      0.00%
           SRAM2:          0 GB       128 KB      0.00%
           SRAM3:         16 KB        32 KB     50.00%
           SRAM4:          0 GB        64 KB      0.00%
            DTCM:          0 GB       128 KB      0.00%
        IDT_LIST:          0 GB         2 KB      0.00%

However, there is no hello world message shown in UART console. Debugger says like below.

(gdb) bt
#0  HAL_LTDC_Init (hltdc=0x24000024 <stm32_ltdc_data_0>)
    at C:/Jeonghyun/zephyrproject/modules/hal/stm32/stm32cube/stm32h7xx/drivers/src/stm32h7xx_hal_ltdc.c:271
#1  0x080033b6 in stm32_ltdc_init (dev=0x800a3b8 <__device_dts_ord_66>)
    at C:/Jeonghyun/zephyrproject/zephyr/drivers/display/display_stm32_ltdc.c:288
#2  0x080046a2 in z_sys_init_run_level (level=2) at C:/Jeonghyun/zephyrproject/zephyr/kernel/device.c:71
#3  0x080047e0 in bg_thread_main (unused1=0x0, unused2=0x0, unused3=0x0)
    at C:/Jeonghyun/zephyrproject/zephyr/kernel/init.c:212
#4  0x08006784 in z_thread_entry (entry=0x80047c9 <bg_thread_main>, p1=0x0, p2=0x0, p3=0x0)
    at C:/Jeonghyun/zephyrproject/zephyr/lib/os/thread_entry.c:36
#5  0x08001afe in arch_switch_to_main_thread (main_thread=0x8006563 <sys_clock_announce+354>,
    stack_ptr=0x24001150 <z_interrupt_stacks+1936> "", _main=0x257f)
    at C:/Jeonghyun/zephyrproject/zephyr/arch/arm/core/aarch32/thread.c:576
#6  0x00000000 in ?? ()
(gdb) b
Note: breakpoint 1 also set at pc 0x8003fc4.
Breakpoint 3 at 0x8003fc4: file C:/Jeonghyun/zephyrproject/modules/hal/stm32/stm32cube/stm32h7xx/drivers/src/stm32h7xx_hal_ltdc.c, line 271.
(gdb) b 272
Note: breakpoint 2 also set at pc 0x8003fd4.
Breakpoint 4 at 0x8003fd4: file C:/Jeonghyun/zephyrproject/modules/hal/stm32/stm32cube/stm32h7xx/drivers/src/stm32h7xx_hal_ltdc.c, line 272.
(gdb) l
266
267       /* Change LTDC peripheral state */
268       hltdc->State = HAL_LTDC_STATE_BUSY;
269
270       /* Configure the HS, VS, DE and PC polarity */
271       hltdc->Instance->GCR &= ~(LTDC_GCR_HSPOL | LTDC_GCR_VSPOL | LTDC_GCR_DEPOL | LTDC_GCR_PCPOL);
272       hltdc->Instance->GCR |= (uint32_t)(hltdc->Init.HSPolarity | hltdc->Init.VSPolarity | \
273                                          hltdc->Init.DEPolarity | hltdc->Init.PCPolarity);
274
275       /* Set Synchronization size */
(gdb) c
Continuing.
Info : halted: PC: 0x08003fc6
halted: PC: 0x08003fc6

UPDATE : bss section or frame_buffer isn't causes. However I am still investigating and Currently stucked because debug session strangly stopped on /modules/hal/stm32/stm32cube/stm32h7xx/drivers/src/stm32h7xx_hal_ltdc.c, line 272 with above log.

[Dictor]

I solved this problem through enabling PLL3. (it was disabled defaultly)