Display driver bus fault in non secure configuration

[SnaiderBG]

Hello

I have been able to run the lvgl sample in the nrf9160dk, however this only works when built in a secure board, when build in non secure a bus fault occurs. Using the addr2line the fault appears in the

ssd16xx_init function, while waiting for the 

!spi_is_ready(&config->bus)

I need this to work in a non secure configuration since I willl be using the modem libraries. Are there any configurations that I need to change to use the display driver in non secure build configurations?

[Håkon Alseth]

Hi,

 

Could you share the full bus fault message?

ssd16xx_init function, while waiting for the 

!spi_is_ready(&config->bus)

If this is the function that faulted, it could indicate that your device is "NULL". How have you described the device in DTS?

 

Kind regards,

Håkon

[SnaiderBG]

I use this overlay to describe the device

&spi3 {
	status = "okay";
	mosi-pin = <11>;
	miso-pin = <12>;
	sck-pin = <13>;
	cs-gpios = <&gpio0 10 GPIO_ACTIVE_LOW>;
	ssd16xxfb@0 {
		//compatible = "solomon,ssd16xxfb", "gooddisplay,gdeh0154a07";
        compatible = "solomon,ssd16xxfb";
		label = "SSD16XX";
		spi-max-frequency = <4000000>;
		reg = <0>;
		height = <200>;
		width = <200>;
		pp-width-bits = <8>;
		pp-height-bits = <16>;
		dc-gpios = <&gpio0 9 GPIO_ACTIVE_LOW>;    /* D9 */
		reset-gpios = <&gpio0 8 GPIO_ACTIVE_LOW>;    /* D8 */
		busy-gpios = <&gpio0 7 GPIO_ACTIVE_HIGH>;    /* D7 */
		gdv = [ 00  ];
		sdv = [ 41 a8 32  ];
		vcom = <0x00>;
		border-waveform = <0x05>;
		tssv = <0x80>;
	};

	st7789v@0 {
		compatible = "sitronix,st7789v";
		label = "ST7789V";
		spi-max-frequency = <20000000>;
		reg = <0>;
		cmd-data-gpios = <&gpio0 9 GPIO_ACTIVE_LOW>; /* D9 */
		reset-gpios = <&gpio0 8 GPIO_ACTIVE_LOW>; /* D8 */
		width = <240>;
		height = <240>;
		x-offset = <0>;
		y-offset = <0>;
		vcom = <0x19>;
		gctrl = <0x35>;
		vrhs = <0x12>;
		vdvs = <0x20>;
		mdac = <0x00>;
		gamma = <0x01>;
		colmod = <0x05>;
		lcm = <0x2c>;
		porch-param = [ 0c 0c 00 33 33  ];
		cmd2en-param = [ 5a 69 02 01  ];
		pwctrl1-param = [ a4 a1  ];
		pvgam-param = [ D0 04 0D 11 13 2B 3F 54 4C 18 0D 0B 1F 23  ];
		nvgam-param = [ D0 04 0C 11 13 2C 3F 44 51 2F 1F 1F 20 23  ];
		ram-param = [ 00 F0  ];
		rgb-param = [ CD 08 14  ];
	};
};

I managed to control the device correctly using the nef9160dk_nrf9160 board in the build configuration

This is the configuration

#Display
CONFIG_DISPLAY=y
CONFIG_DISPLAY_LOG_LEVEL_ERR=y

CONFIG_SPI=y 
CONFIG_SSD16XX=y

#LVGL
CONFIG_LVGL_DISPLAY_DEV_NAME="SSD16XX"
CONFIG_LVGL_HOR_RES_MAX=200
CONFIG_LVGL_VER_RES_MAX=200
CONFIG_LVGL_VDB_SIZE=100
CONFIG_LVGL_DPI=180
CONFIG_LVGL_BITS_PER_PIXEL=1
CONFIG_LVGL_COLOR_DEPTH_1=y

CONFIG_LVGL=y
CONFIG_LVGL_USE_LABEL=y
CONFIG_LVGL_USE_CONT=y
CONFIG_LVGL_USE_THEME_MATERIAL=y
CONFIG_LVGL_USE_IMG=y
CONFIG_LVGL_USE_DEBUG=y

CONFIG_LVGL_TXT_ENC_UTF8=y

CONFIG_LVGL_FONT_MONTSERRAT_18=y

CONFIG_LVGL_THEME_DEFAULT_FONT_NORMAL_MONTSERRAT_18=y

This is the error in the sample "out of the box"

 

When I tried it in the complete program

Thanks

[Håkon Alseth]

Hi,

 

Could this be the root of the issue?

https://github.com/zephyrproject-rtos/zephyr/commit/5e722c436842068c3ac1d75b440ea505035dfaf6

Could you try to add this workaround (switch the two lines) and see if this helps?

 

Kind regards,

Håkon

[SnaiderBG]

Thanks, seems to have solved the problem