Imx7d lcdif not working with BSP 5.0

Technical Support
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1

Hello

I have probem to get working LCD interface with Winstar Display(1280x800) using BSP 5.0(dunfell Yocto).
System image which was created using BSP 3.0(thud Yocto) worked without issues, but I needed newer kernel with microchip DSA ethernet switch driver so I moved to BSP 5.0.
Now I have blank screen in Linux(also in u-boot(it didn’t worked under BSP 3.0)).

My devicetree-node looks like below:

&lcdif {
	display = <&display0>;
	lcd-supply = <&reg_3v3>;
	status = "okay";

	display0: lcd-display {
		bits-per-pixel = <16>;
		bus-width = <18>;

		display-timings {
			native-mode = <&timing_wxga>;

			/* Standard WXGA timing */
			timing_wxga: 1280x800 {
				clock-frequency = <71100000>;
				hactive = <1280>;
				vactive = <800>;
				hfront-porch = <70>;
				hback-porch = <70>;
				hsync-len = <20>;
				vback-porch = <10>;
				vfront-porch = <10>;
				vsync-len = <3>;

				de-active = <1>;
				hsync-active = <0>;
				vsync-active = <0>;
				pixelclk-active = <0>;
			};
		};
	};
};

To get cleanest comparison environment I’ve downloaded 2 reference images from:

Then I used prebulid kernel images in my image

1| BSP 3.0 Linux LXDE Image 2.8b6 :

Linux version 4.14.159-3.0.3+gfff496c2a1bd

[ 0.205171] mxsfb 30730000.lcdif: initialized

lcdif works as desired

2| BSP 5.0 Linux Reference Multimedia Downstream SoC vendor based kernel Wayland/XWayland graphics back-end included 5.0.0

Linux version 5.4.47-5.0.0+git.9e7307657fc1

[ 0.206173] mxsfb 30730000.lcdif: initialized

blank screen, no image

Also no luck with msxfb_drm driver(CONFIG_FB_MXS is disabled then) with this device-tree setup kernel won’t fully boot, also no image:

/{
	panel: panel {
		compatible = "innolux,g101ice-l01";
		label = "display-panel";
		backlight = <&bl>;
		power-supply = <&reg_3v3>;

		port {
			panel_in: endpoint {
				remote-endpoint = <&lcdif_out>;
			};
		};
	};
};

&lcdif {
        lcd-supply = <&reg_3v3>;
        status = "okay";

	
	port {
		lcdif_out: endpoint {
			remote-endpoint = <&panel_in>;
		};
	};
};
2

Hi @qba

Can you check what modes the interface has configured? Run the following command:

for test in $(ls /sys/class/drm/); do echo CARD: $test; cat /sys/class/drm/$test/modes; cat  /sys/class/drm/$test/enabled; done

Regards,
Stefan

3

Hello @stefan_e.tx I was away from work because of Christmas

Can you check what modes the interface has configured?

Result:

cat: /sys/class/drm/version/modes: Not a directory
cat: /sys/class/drm/version/enabled: Not a directory

And it is nothing suprising because by default framebuffer driver is used(and DRM subsystem is not enabled):
I am using colibri_imx7_defconfig

https://git.toradex.com/cgit/linux-toradex.git/tree/arch/arm/configs/colibri_imx7_defconfig?h=toradex_5.4-2.1.x-imx

CONFIG_FB_MXS=y

I have device /dev/fb0
as well as
/sys/class/graphics/fb0/

Content of interesting files inside:

/sys/devices/soc0/soc/30400000.aips-bus/30730000.lcdif/graphics/fb0/blank

turns off LCD backlight when 1  and turns on LCD backlight when 0. No image

/sys/devices/soc0/soc/30400000.aips-bus/30730000.lcdif/graphics/fb0/bits_per_pixel

16
No effect when changing to 8, 16 or 32  No image

/sys/devices/soc0/soc/30400000.aips-bus/30730000.lcdif/graphics/fb0/modes

U:1280x800p-59
U:1280x800p-59
U:1024x768p-60
U:800x600p-60
U:800x480p-53
U:640x480p-59

/sys/devices/soc0/soc/30400000.aips-bus/30730000.lcdif/graphics/fb0/mode

empty. 

Default fbset result:

mode "1280x800-60"
        # D: 71.104 MHz, H: 49.377 kHz, V: 59.997 Hz
        geometry 1280 800 1280 1600 16
        timings 14064 70 70 10 10 20 3
        accel false
        rgba 5/11,6/5,5/0,0/0
endmode

Setting modes from list, for example:
echo U:1280x800p-59 > mode 
No effect - only mode file content is changed to U:1280x800p-59
4

Hi @qba

The timings look fine. What kind of parallel RGB to LVDS converter do you use? Could it be that there is some enable signal missing? Can you maybe share the schematic, the full device tree which is working and the one that doesn’t work and the full dmesg log?
Also can you measure the clock signal before the parallel RGB to LVDS converter and after it? Is the signal there or is it missing?

Regards,
Stefan

5

@stefan_e.tx
The hardware is fine, it works with kernel 4.14.159 from Yocto thud release(BSP 3.0), I also have Colibri imx6s and it works with system image based on BSP 5.0 but lcd peripherals + driver are different than in imx7d.

What kind of parallel RGB to LVDS converter do you use?

DS90C385

Could it be that there is some enable signal missing?

According to my investigations: no

Can you maybe share the schematic, the full device tree which is working and the one that doesn’t work and the full dmesg log?

Unfortunatelly I can’t share the schematic or full devicetree without Product Manager permission. Device0tree lcdif fragment is like posted at the beginning
Here is full dmesg log:

[    0.000000] Booting Linux on physical CPU 0x0
[    0.000000] Linux version 5.4.77-0+git.8fc7bd5da76f (oe-user@oe-host) (gcc version 9.3.0 (GCC)) #1 SMP Mon Nov 30 08:44:04 UTC 2020
[    0.000000] CPU: ARMv7 Processor [410fc075] revision 5 (ARMv7), cr=10c5387d
[    0.000000] CPU: div instructions available: patching division code
[    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache
[    0.000000] OF: fdt: Machine model: Toradex Colibri iMX7D 1GB (eMMC) on PSM02_MB_02 Board
[    0.000000] Memory policy: Data cache writealloc
[    0.000000] cma: Reserved 256 MiB at 0xb0000000
[    0.000000] On node 0 totalpages: 262144
[    0.000000]   Normal zone: 2048 pages used for memmap
[    0.000000]   Normal zone: 0 pages reserved
[    0.000000]   Normal zone: 262144 pages, LIFO batch:63
[    0.000000] percpu: Embedded 15 pages/cpu s31948 r8192 d21300 u61440
[    0.000000] pcpu-alloc: s31948 r8192 d21300 u61440 alloc=15*4096
[    0.000000] pcpu-alloc: [0] 0 [0] 1
[    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 260096
[    0.000000] Kernel command line: root=/dev/mmcblk0p1 rw rootwait console=tty1 console=ttymxc0,115200n8 consoleblank=0
[    0.000000] Dentry cache hash table entries: 131072 (order: 7, 524288 bytes, linear)
[    0.000000] Inode-cache hash table entries: 65536 (order: 6, 262144 bytes, linear)
[    0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off
[    0.000000] Memory: 761216K/1048576K available (9216K kernel code, 668K rwdata, 2972K rodata, 1024K init, 392K bss, 25216K reserved, 262144K cma-reserved)
[    0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=2, Nodes=1
[    0.000000] rcu: Hierarchical RCU implementation.
[    0.000000] rcu:     RCU event tracing is enabled.
[    0.000000] rcu:     RCU restricting CPUs from NR_CPUS=4 to nr_cpu_ids=2.
[    0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 10 jiffies.
[    0.000000] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=2
[    0.000000] NR_IRQS: 16, nr_irqs: 16, preallocated irqs: 16
[    0.000000] arch_timer: cp15 timer(s) running at 8.00MHz (phys).
[    0.000000] clocksource: arch_sys_counter: mask: 0xffffffffffffff max_cycles: 0x1d854df40, max_idle_ns: 440795202120 ns
[    0.000008] sched_clock: 56 bits at 8MHz, resolution 125ns, wraps every 2199023255500ns
[    0.000021] Switching to timer-based delay loop, resolution 125ns
[    0.000318] Ignoring duplicate/late registration of read_current_timer delay
[    0.000342] clocksource: mxc_timer1: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 637086815595 ns
[    0.001567] arch_timer: multiple nodes in dt, skipping
[    0.001881] Console: colour dummy device 80x30
[    0.002249] printk: console [tty1] enabled
[    0.002285] Calibrating delay loop (skipped), value calculated using timer frequency.. 16.00 BogoMIPS (lpj=80000)
[    0.002317] pid_max: default: 32768 minimum: 301
[    0.002469] Mount-cache hash table entries: 2048 (order: 1, 8192 bytes, linear)
[    0.002503] Mountpoint-cache hash table entries: 2048 (order: 1, 8192 bytes, linear)
[    0.003309] CPU: Testing write buffer coherency: ok
[    0.004162] Setting up static identity map for 0x80100000 - 0x80100060
[    0.004299] rcu: Hierarchical SRCU implementation.
[    0.004639] smp: Bringing up secondary CPUs ...
[    0.005444] smp: Brought up 1 node, 2 CPUs
[    0.005468] SMP: Total of 2 processors activated (32.00 BogoMIPS).
[    0.005485] CPU: All CPU(s) started in SVC mode.
[    0.005916] devtmpfs: initialized
[    0.016619] random: get_random_u32 called from bucket_table_alloc+0x58/0x14c with crng_init=0
[    0.017056] VFP support v0.3: implementor 41 architecture 2 part 30 variant 7 rev 5
[    0.017383] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 19112604462750000 ns
[    0.017428] futex hash table entries: 512 (order: 3, 32768 bytes, linear)
[    0.027305] pinctrl core: initialized pinctrl subsystem
[    0.028443] NET: Registered protocol family 16
[    0.034634] DMA: preallocated 256 KiB pool for atomic coherent allocations
[    0.035872] cpuidle: using governor menu
[    0.043039] vdd1p0d: Bringing 0uV into 800000-800000uV
[    0.043301] vdd1p0d: supplied by regulator-dummy
[    0.043787] vdd1p2: supplied by regulator-dummy
[    0.046244] DDR type is DDR3!
[    0.054382] imx7d_enet_clk_sel: fec-18: failed to get enet_out clock, assuming ext. clock source
[    0.054440] imx7d_enet_clk_sel: fec-18: found enet_out clock, assuming internal clock source
[    0.054596] hw-breakpoint: found 5 (+1 reserved) breakpoint and 4 watchpoint registers.
[    0.054622] hw-breakpoint: maximum watchpoint size is 8 bytes.
[    0.055049] imx7d-pinctrl 302c0000.iomuxc-lpsr: initialized IMX pinctrl driver
[    0.055742] imx7d-pinctrl 30330000.iomuxc: initialized IMX pinctrl driver
[    0.056874] imx mu driver is registered.
[    0.057367] imx rpmsg driver is registered.
[    0.058665] MU is ready for cross core communication!
[    0.089250] SCSI subsystem initialized
[    0.089537] usbcore: registered new interface driver usbfs
[    0.089608] usbcore: registered new interface driver hub
[    0.089725] usbcore: registered new device driver usb
[    0.089883] usb_phy_generic usbphynop1: usbphynop1 supply vcc not found, using dummy regulator
[    0.090183] usb_phy_generic usbphynop3: usbphynop3 supply vcc not found, using dummy regulator
[    0.090529] usb_phy_generic usbphynop2: usbphynop2 supply vcc not found, using dummy regulator
[    0.091230] i2c-gpio i2c@5: using lines 119 (SDA) and 38 (SCL)
[    0.092309] i2c i2c-0: IMX I2C adapter registered
[    0.093296] i2c i2c-3: IMX I2C adapter registered
[    0.093525] videodev: Linux video capture interface: v2.00
[    0.093601] pps_core: LinuxPPS API ver. 1 registered
[    0.093619] pps_core: Software ver. 5.3.6 - Copyright 2005-2007 Rodolfo Giometti <giometti@linux.it>
[    0.093660] PTP clock support registered
[    0.095040] clocksource: Switched to clocksource arch_sys_counter
[    0.095214] VFS: Disk quotas dquot_6.6.0
[    0.095301] VFS: Dquot-cache hash table entries: 1024 (order 0, 4096 bytes)
[    0.104113] thermal_sys: Registered thermal governor 'step_wise'
[    0.104507] NET: Registered protocol family 2
[    0.105171] tcp_listen_portaddr_hash hash table entries: 512 (order: 0, 6144 bytes, linear)
[    0.105225] TCP established hash table entries: 8192 (order: 3, 32768 bytes, linear)
[    0.105329] TCP bind hash table entries: 8192 (order: 4, 65536 bytes, linear)
[    0.105486] TCP: Hash tables configured (established 8192 bind 8192)
[    0.105603] UDP hash table entries: 512 (order: 2, 16384 bytes, linear)
[    0.105671] UDP-Lite hash table entries: 512 (order: 2, 16384 bytes, linear)
[    0.105882] NET: Registered protocol family 1
[    0.106434] RPC: Registered named UNIX socket transport module.
[    0.106460] RPC: Registered udp transport module.
[    0.106476] RPC: Registered tcp transport module.
[    0.106490] RPC: Registered tcp NFSv4.1 backchannel transport module.
[    0.107211] hw perfevents: enabled with armv7_cortex_a7 PMU driver, 5 counters available
[    0.108362] Bus freq driver module loaded
[    0.109360] Initialise system trusted keyrings
[    0.109566] workingset: timestamp_bits=30 max_order=18 bucket_order=0
[    0.115996] NFS: Registering the id_resolver key type
[    0.116047] Key type id_resolver registered
[    0.116063] Key type id_legacy registered
[    0.116088] nfs4filelayout_init: NFSv4 File Layout Driver Registering...
[    0.116841] Key type cifs.idmap registered
[    0.116870] ntfs: driver 2.1.32 [Flags: R/W].
[    0.117325] fuse: init (API version 7.31)
[    0.163877] Key type asymmetric registered
[    0.163906] Asymmetric key parser 'x509' registered
[    0.163936] io scheduler mq-deadline registered
[    0.163953] io scheduler kyber registered
[    0.169482] mxs-dma 33000000.dma-apbh: initialized
[    0.171477] 30860000.serial: ttymxc0 at MMIO 0x30860000 (irq = 52, base_baud = 1500000) is a IMX
[    0.854025] printk: console [ttymxc0] enabled
[    0.859030] 30890000.serial: ttymxc1 at MMIO 0x30890000 (irq = 53, base_baud = 1500000) is a IMX
[    0.868399] 30880000.serial: ttymxc2 at MMIO 0x30880000 (irq = 54, base_baud = 1500000) is a IMX
[    0.890919] loop: module loaded
[    0.895243] at24 3-0052: 256 byte 24c02 EEPROM, writable, 1 bytes/write
[    0.902875] at24 3-0053: 256 byte 24c02 EEPROM, writable, 1 bytes/write
[    0.925723] spi_imx 30840000.spi: dma setup error -19, use pio
[    0.932199] spi_imx 30840000.spi: probed
[    0.937063] libphy: Fixed MDIO Bus: probed
[    0.941561] CAN device driver interface
[    0.950119] pps pps0: new PPS source ptp0
[    0.955843] libphy: fec_enet_mii_bus: probed
[    0.961765] fec 30be0000.ethernet eth0: registered PHC device 0
[    0.968034] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
[    0.974579] ehci-mxc: Freescale On-Chip EHCI Host driver
[    0.980278] ehci-fsl: Freescale EHCI Host controller driver
[    1.075597] input: AD7879 Touchscreen as /devices/soc0/soc/30800000.aips-bus/30a20000.i2c/i2c-0/0-002c/input/input0
[    1.094576] rtc-ds1307 3-006f: registered as rtc0
[    1.100152] snvs_rtc 30370000.snvs:snvs-rtc-lp: registered as rtc1
[    1.106546] i2c /dev entries driver
[    1.111175] pps_ldisc: PPS line discipline registered
[    1.117981] imx2-wdt 30280000.wdog: timeout 60 sec (nowayout=0)
[    1.124615] sdhci: Secure Digital Host Controller Interface driver
[    1.130837] sdhci: Copyright(c) Pierre Ossman
[    1.135218] sdhci-pltfm: SDHCI platform and OF driver helper
[    1.141941] sdhci-esdhc-imx 30b40000.usdhc: Got CD GPIO
[    1.179222] mmc1: SDHCI controller on 30b40000.usdhc [30b40000.usdhc] using ADMA
[    1.214405] mmc0: SDHCI controller on 30b60000.usdhc [30b60000.usdhc] using ADMA
[    1.223927] caam 30900000.caam: device ID = 0x0a16030000000000 (Era 8)
[    1.230528] caam 30900000.caam: job rings = 3, qi = 0
[    1.245280] caam algorithms registered in /proc/crypto
[    1.251883] caam 30900000.caam: caam pkc algorithms registered in /proc/crypto
[    1.261367] caam_jr 30901000.jr0: registering rng-caam
[    1.268372] hidraw: raw HID events driver (C) Jiri Kosina
[    1.274012] usbcore: registered new interface driver usbhid
[    1.279650] usbhid: USB HID core driver
[    1.285776] mmc1: new high speed SDHC card at address 1234
[    1.292013] mmcblk1: mmc1:1234 SA16G 14.5 GiB
[    1.296847] coresight etm0: ETM 3.5 initialized
[    1.301992] coresight etm1: ETM 3.5 initialized
[    1.305232]  mmcblk1: p1
[    1.310380] NET: Registered protocol family 10
[    1.315922] Segment Routing with IPv6
[    1.319816] NET: Registered protocol family 17
[    1.324336] Bridge firewalling registered
[    1.328615] can: controller area network core (rev 20170425 abi 9)
[    1.334891] NET: Registered protocol family 29
[    1.339449] 8021q: 802.1Q VLAN Support v1.8
[    1.342261] mmc0: new HS200 MMC card at address 0001
[    1.343888] tsn generic netlink module v1 init...
[    1.349458] mmcblk0: mmc0:0001 Q2J54A 3.64 GiB
[    1.353520] Key type dns_resolver registered
[    1.358272] mmcblk0boot0: mmc0:0001 Q2J54A partition 1 2.00 MiB
[    1.368555] mmcblk0boot1: mmc0:0001 Q2J54A partition 2 2.00 MiB
[    1.368787] Registering SWP/SWPB emulation handler
[    1.374764] mmcblk0rpmb: mmc0:0001 Q2J54A partition 3 512 KiB, chardev (248:0)
[    1.386729] registered taskstats version 1
[    1.388429]  mmcblk0: p1 p2
[    1.390852] Loading compiled-in X.509 certificates
[    1.437339] random: fast init done
[    1.440798] rtc-ds1307 3-006f: setting system clock to 2020-12-30T14:19:19 UTC (1609337959)
[    1.489378] EXT4-fs (mmcblk0p1): recovery complete
[    1.494700] EXT4-fs (mmcblk0p1): mounted filesystem with ordered data mode. Opts: (null)
[    1.502885] ext4 filesystem being mounted at /root supports timestamps until 2038 (0x7fffffff)
[    1.511577] VFS: Mounted root (ext4 filesystem) on device 179:9.
[    1.518317] devtmpfs: mounted
[    1.522922] Freeing unused kernel memory: 1024K
[    1.535372] Run /sbin/init as init process
[    1.864810] udevd[183]: starting version 3.2.9
[    1.877722] random: udevd: uninitialized urandom read (16 bytes read)
[    1.885194] random: udevd: uninitialized urandom read (16 bytes read)
[    1.891758] random: udevd: uninitialized urandom read (16 bytes read)
[    1.920543] udevd[184]: starting eudev-3.2.9
[    2.054545] caam-snvs 30370000.caam-snvs: can't get snvs clock
[    2.065493] caam-snvs 30370000.caam-snvs: violation handlers armed - non-secure state
[    2.081663] mxsfb_kmod: loading out-of-tree module taints kernel.
[    2.096079] mxsfb 30730000.lcdif: 30730000.lcdif supply lcd not found, using dummy regulator
[    2.107827] mxsfb 30730000.lcdif: Using timings from devicetree
[    2.199455] Console: switching to colour frame buffer device 160x50
[    2.218590] mxsfb 30730000.lcdif: initialized
[    2.251706] imx-sdma 30bd0000.sdma: Direct firmware load for imx/sdma/sdma-imx7d.bin failed with error -2
[    2.266143] imx-sdma 30bd0000.sdma: Direct firmware load for imx/sdma/sdma-imx7d.bin failed with error -2
[    2.277114] imx-sdma 30bd0000.sdma: external firmware not found, using ROM firmware
[    2.556524] ext4 filesystem being mounted at /media/mmc-mmcblk0p1 supports timestamps until 2038 (0x7fffffff)
[    2.589617] EXT4-fs (mmcblk0p2): Unrecognized mount option "gid=100" or missing value
[    3.342373] urandom_read: 2 callbacks suppressed
[    3.342382] random: udevd: uninitialized urandom read (16 bytes read)
[    3.355291] random: udevd: uninitialized urandom read (16 bytes read)
[    3.397973] EXT4-fs (mmcblk0p1): re-mounted. Opts: (null)
[    3.403524] ext4 filesystem being remounted at / supports timestamps until 2038 (0x7fffffff)
[    4.044776] random: dd: uninitialized urandom read (512 bytes read)
[    4.191633] Micrel KSZ8041 30be0000.ethernet-1:00: attached PHY driver [Micrel KSZ8041] (mii_bus:phy_addr=30be0000.ethernet-1:00, irq=POLL)
[    4.353356] urandom_read: 1 callbacks suppressed
[    4.353366] random: dbus-daemon: uninitialized urandom read (12 bytes read)
[    4.570415] cfg80211: Loading compiled-in X.509 certificates for regulatory database
[    4.580650] cfg80211: Loaded X.509 cert 'sforshee: 00b28ddf47aef9cea7'
[   31.835148] 5V: disabling
[   31.837793] reg_usb_otg2_vbus: disabling
[   31.841719] reg-disp: disabling
[   31.844865] reg_can_vbus: disabling

Also can you measure the clock signal before the parallel RGB to LVDS converter and after it? Is the signal there or is it missing?

Yup, there is a problem with CLK signal:
on pin LCD_RGB_CLK(Colibri pin 56) signal frequency is about 24.1 MHz despite that fbset says that it should be around 71 MHz

mode "1280x800-60"
        # D: 71.104 MHz, H: 49.377 kHz, V: 59.997 Hz
        geometry 1280 800 1280 800 16
        timings 14064 70 70 10 10 20 3
        accel false
        rgba 5/11,6/5,5/0,0/0
endmode

Also checked kernel version 4.14.159-3.0.3+gfff496c2a1bd - LCD works OK here.
Measured LCD_RGB_CLK signal frequency is 71 MHz.
Please don’t care about many warnings - I’ve just taken raw kernel image from BSP-3.0 reference image and put it into my system image rootfs. Here is bootlog

[    0.000000] Booting Linux on physical CPU 0x0
[    0.000000] Linux version 4.14.159-3.0.3+gfff496c2a1bd (oe-user@oe-host) (gcc version 8.2.0 (GCC)) #1 SMP Wed Jan 1 02:55:16 UTC 2020
[    0.000000] CPU: ARMv7 Processor [410fc075] revision 5 (ARMv7), cr=10c5387d
[    0.000000] CPU: div instructions available: patching division code
[    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache
[    0.000000] OF: fdt: Machine model: Toradex Colibri iMX7D 1GB (eMMC) on PSM02_MB_02 Board
[    0.000000] Memory policy: Data cache writealloc
[    0.000000] cma: Reserved 256 MiB at 0xb0000000
[    0.000000] percpu: Embedded 15 pages/cpu s30924 r8192 d22324 u61440
[    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 260096
[    0.000000] Kernel command line: root=/dev/mmcblk0p1 rw rootwait console=tty1 console=ttymxc0,115200n8 consoleblank=0
[    0.000000] PID hash table entries: 4096 (order: 2, 16384 bytes)
[    0.000000] Dentry cache hash table entries: 131072 (order: 7, 524288 bytes)
[    0.000000] Inode-cache hash table entries: 65536 (order: 6, 262144 bytes)
[    0.000000] Memory: 763528K/1048576K available (8192K kernel code, 352K rwdata, 2372K rodata, 1024K init, 393K bss, 22904K reserved, 262144K cma-reserved)
[    0.000000] Virtual kernel memory layout:
[    0.000000]     vector  : 0xffff0000 - 0xffff1000   (   4 kB)
[    0.000000]     fixmap  : 0xffc00000 - 0xfff00000   (3072 kB)
[    0.000000]     vmalloc : 0xc0800000 - 0xff800000   (1008 MB)
[    0.000000]     lowmem  : 0x80000000 - 0xc0000000   (1024 MB)
[    0.000000]     modules : 0x7f000000 - 0x80000000   (  16 MB)
[    0.000000]       .text : 0x80008000 - 0x80900000   (9184 kB)
[    0.000000]       .init : 0x80c00000 - 0x80d00000   (1024 kB)
[    0.000000]       .data : 0x80d00000 - 0x80d581e0   ( 353 kB)
[    0.000000]        .bss : 0x80d5a000 - 0x80dbc4d0   ( 394 kB)
[    0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=2, Nodes=1
[    0.000000] Hierarchical RCU implementation.
[    0.000000]  RCU event tracing is enabled.
[    0.000000]  RCU restricting CPUs from NR_CPUS=4 to nr_cpu_ids=2.
[    0.000000] RCU: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=2
[    0.000000] NR_IRQS: 16, nr_irqs: 16, preallocated irqs: 16
[    0.000000] arch_timer: cp15 timer(s) running at 8.00MHz (phys).
[    0.000000] clocksource: arch_sys_counter: mask: 0xffffffffffffff max_cycles: 0x1d854df40, max_idle_ns: 440795202120 ns
[    0.000007] sched_clock: 56 bits at 8MHz, resolution 125ns, wraps every 2199023255500ns
[    0.000020] Switching to timer-based delay loop, resolution 125ns
[    0.000339] Ignoring duplicate/late registration of read_current_timer delay
[    0.000358] clocksource: mxc_timer1: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 637086815595 ns
[    0.001809] arch_timer: multiple nodes in dt, skipping
[    0.002168] Console: colour dummy device 80x30
[    0.002601] console [tty1] enabled
[    0.002629] Calibrating delay loop (skipped), value calculated using timer frequency.. 16.00 BogoMIPS (lpj=80000)
[    0.002660] pid_max: default: 32768 minimum: 301
[    0.002802] Mount-cache hash table entries: 2048 (order: 1, 8192 bytes)
[    0.002829] Mountpoint-cache hash table entries: 2048 (order: 1, 8192 bytes)
[    0.003454] CPU: Testing write buffer coherency: ok
[    0.004105] Setting up static identity map for 0x80100000 - 0x80100060
[    0.004239] Hierarchical SRCU implementation.
[    0.004807] smp: Bringing up secondary CPUs ...
[    0.005589] smp: Brought up 1 node, 2 CPUs
[    0.005614] SMP: Total of 2 processors activated (32.00 BogoMIPS).
[    0.005631] CPU: All CPU(s) started in SVC mode.
[    0.006413] devtmpfs: initialized
[    0.016780] random: get_random_u32 called from bucket_table_alloc+0x100/0x230 with crng_init=0
[    0.017199] VFP support v0.3: implementor 41 architecture 2 part 30 variant 7 rev 5
[    0.017459] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 19112604462750000 ns
[    0.017498] futex hash table entries: 512 (order: 3, 32768 bytes)
[    0.026701] pinctrl core: initialized pinctrl subsystem
[    0.027670] NET: Registered protocol family 16
[    0.033321] DMA: preallocated 256 KiB pool for atomic coherent allocations
[    0.034346] cpuidle: using governor menu
[    0.041357] vdd1p0d: supplied by regulator-dummy
[    0.041834] vdd1p2: supplied by regulator-dummy
[    0.044239] DDR type is DDR3!
[    0.051991] imx7d_enet_clk_sel: fec-18: failed to get enet_out clock, assuming ext. clock source
[    0.052078] imx7d_enet_clk_sel: fec-18: found enet_out clock, assuming internal clock source
[    0.052238] hw-breakpoint: found 5 (+1 reserved) breakpoint and 4 watchpoint registers.
[    0.052264] hw-breakpoint: maximum watchpoint size is 8 bytes.
[    0.052545] imx7d-pinctrl 302c0000.iomuxc-lpsr: initialized IMX pinctrl driver
[    0.053191] imx7d-pinctrl 30330000.iomuxc: initialized IMX pinctrl driver
[    0.054303] imx rpmsg driver is registered.
[    0.055165] MU is ready for cross core communication!
[    0.062551] gpio gpiochip0: names 16 do not match number of GPIOs 32
[    0.065231] gpio gpiochip2: names 29 do not match number of GPIOs 32
[    0.066567] gpio gpiochip3: names 24 do not match number of GPIOs 32
[    0.067890] gpio gpiochip4: names 18 do not match number of GPIOs 32
[    0.069210] gpio gpiochip5: names 23 do not match number of GPIOs 32
[    0.070591] gpio gpiochip6: names 15 do not match number of GPIOs 32
[    0.074763] SCSI subsystem initialized
[    0.074988] usbcore: registered new interface driver usbfs
[    0.075051] usbcore: registered new interface driver hub
[    0.075156] usbcore: registered new device driver usb
[    0.075289] usb_phy_generic usbphynop1: usbphynop1 supply vcc not found, using dummy regulator
[    0.075452] usb_phy_generic usbphynop3: usbphynop3 supply vcc not found, using dummy regulator
[    0.075735] usb_phy_generic usbphynop2: usbphynop2 supply vcc not found, using dummy regulator
[    0.076749] i2c i2c-0: IMX I2C adapter registered
[    0.076781] i2c i2c-0: can't use DMA, using PIO instead.
[    0.077548] i2c i2c-3: IMX I2C adapter registered
[    0.077576] i2c i2c-3: can't use DMA, using PIO instead.
[    0.077771] Linux video capture interface: v2.00
[    0.077846] pps_core: LinuxPPS API ver. 1 registered
[    0.077865] pps_core: Software ver. 5.3.6 - Copyright 2005-2007 Rodolfo Giometti <giometti@linux.it>
[    0.077902] PTP clock support registered
[    0.078154] Advanced Linux Sound Architecture Driver Initialized.
[    0.079360] clocksource: Switched to clocksource arch_sys_counter
[    0.079514] VFS: Disk quotas dquot_6.6.0
[    0.079586] VFS: Dquot-cache hash table entries: 1024 (order 0, 4096 bytes)
[    0.087522] NET: Registered protocol family 2
[    0.088130] TCP established hash table entries: 8192 (order: 3, 32768 bytes)
[    0.088234] TCP bind hash table entries: 8192 (order: 4, 65536 bytes)
[    0.088388] TCP: Hash tables configured (established 8192 bind 8192)
[    0.088499] UDP hash table entries: 512 (order: 2, 16384 bytes)
[    0.088563] UDP-Lite hash table entries: 512 (order: 2, 16384 bytes)
[    0.088750] NET: Registered protocol family 1
[    0.089136] RPC: Registered named UNIX socket transport module.
[    0.089161] RPC: Registered udp transport module.
[    0.089177] RPC: Registered tcp transport module.
[    0.089192] RPC: Registered tcp NFSv4.1 backchannel transport module.
[    0.089960] hw perfevents: enabled with armv7_cortex_a7 PMU driver, 5 counters available
[    0.091427] Bus freq driver module loaded
[    0.092545] workingset: timestamp_bits=30 max_order=18 bucket_order=0
[    0.097270] NFS: Registering the id_resolver key type
[    0.097328] Key type id_resolver registered
[    0.097345] Key type id_legacy registered
[    0.097369] nfs4filelayout_init: NFSv4 File Layout Driver Registering...
[    0.097866] ntfs: driver 2.1.32 [Flags: R/W].
[    0.098140] fuse init (API version 7.26)
[    0.104307] io scheduler noop registered
[    0.104341] io scheduler deadline registered
[    0.104508] io scheduler cfq registered (default)
[    0.104530] io scheduler mq-deadline registered
[    0.104546] io scheduler kyber registered
[    0.108242] mxsfb 30730000.lcdif: 30730000.lcdif supply lcd not found, using dummy regulator
[    0.108377] mxsfb 30730000.lcdif: Using timings from devicetree
[    0.189213] Console: switching to colour frame buffer device 160x50
[    0.204896] mxsfb 30730000.lcdif: initialized
[    0.207286] mxs-dma 33000000.dma-apbh: initialized
[    0.208307] imx-gpcv2 303a0000.gpc: 303a0000.gpc supply mipi-phy not found, using dummy regulator
[    0.208542] imx-gpcv2 303a0000.gpc: 303a0000.gpc supply pcie-phy not found, using dummy regulator
[    0.208742] imx-gpcv2 303a0000.gpc: 303a0000.gpc supply vcc not found, using dummy regulator
[    0.210897] 30860000.serial: ttymxc0 at MMIO 0x30860000 (irq = 52, base_baud = 1500000) is a IMX
[    1.004412] console [ttymxc0] enabled
[    1.008762] 30890000.serial: ttymxc1 at MMIO 0x30890000 (irq = 53, base_baud = 1500000) is a IMX
[    1.018312] 30880000.serial: ttymxc2 at MMIO 0x30880000 (irq = 54, base_baud = 1500000) is a IMX
[    1.034885] loop: module loaded
[    1.039067] at24 3-0052: 256 byte 24c02 EEPROM, writable, 1 bytes/write
[    1.046756] at24 3-0053: 256 byte 24c02 EEPROM, writable, 1 bytes/write
[    1.069052] spi_imx 30840000.spi: dma setup error -19, use pio
[    1.075612] spi_imx 30840000.spi: probed
[    1.080214] libphy: Fixed MDIO Bus: probed
[    1.090744] pps pps0: new PPS source ptp0
[    1.100770] libphy: fec_enet_mii_bus: probed
[    1.109785] fec 30be0000.ethernet eth0: registered PHC device 0
[    1.119245] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
[    1.129072] ehci-mxc: Freescale On-Chip EHCI Host driver
[    1.137868] usbcore: registered new interface driver usb-storage
[    1.147269] usbcore: registered new interface driver usbserial
[    1.156393] usbcore: registered new interface driver usbserial_generic
[    1.166177] usbserial: USB Serial support registered for generic
[    1.175491] usbcore: registered new interface driver ftdi_sio
[    1.184552] usbserial: USB Serial support registered for FTDI USB Serial Device
[    1.195212] usbcore: registered new interface driver pl2303
[    1.204083] usbserial: USB Serial support registered for pl2303
[    1.214422] usbmisc_imx 30b10200.usbmisc: 30b10200.usbmisc supply vbus-wakeup not found, using dummy regulator
[    1.228073] usbmisc_imx 30b30200.usbmisc: 30b30200.usbmisc supply vbus-wakeup not found, using dummy regulator
[    1.241644] usbmisc_imx 30b20200.usbmisc: 30b20200.usbmisc supply vbus-wakeup not found, using dummy regulator
[    1.255778] imx_usb 30b10000.usb: 30b10000.usb supply vbus not found, using dummy regulator
[    1.272381] imx7d-pinctrl 30330000.iomuxc: pin MX7D_PAD_UART3_CTS_B already requested by regulators-pm:regulator-usbh-vbus; cannot claim for 30b20000.usb
[    1.289736] imx7d-pinctrl 30330000.iomuxc: pin-81 (30b20000.usb) status -22
[    1.300216] imx7d-pinctrl 30330000.iomuxc: could not request pin 81 (MX7D_PAD_UART3_CTS_B) from group usbotg2_grp  on device 30330000.iomuxc
[    1.316502] imx_usb 30b20000.usb: Error applying setting, reverse things back
[    1.327365] imx_usb: probe of 30b20000.usb failed with error -22
[    1.340512] input: AD7879 Touchscreen as /devices/soc0/soc/30800000.aips-bus/30a20000.i2c/i2c-0/0-002c/input/input0
[    1.364112] rtc-ds1307 3-006f: registered as rtc0
[    1.373407] snvs_rtc 30370000.snvs:snvs-rtc-lp: registered as rtc1
[    1.383787] i2c /dev entries driver
[    1.391621] IR NEC protocol handler initialized
[    1.400081] IR RC5(x/sz) protocol handler initialized
[    1.409009] IR RC6 protocol handler initialized
[    1.417395] IR JVC protocol handler initialized
[    1.425712] IR Sony protocol handler initialized
[    1.434154] IR SANYO protocol handler initialized
[    1.442594] IR Sharp protocol handler initialized
[    1.451033] IR MCE Keyboard/mouse protocol handler initialized
[    1.460631] IR XMP protocol handler initialized
[    1.469808] imx_thermal tempmon: failed to get sensor regmap: -19
[    1.479603] imx_thermal tempmon: failed to get sensor data
[    1.489776] imx2-wdt 30280000.wdog: timeout 60 sec (nowayout=0)
[    1.500470] cpu cpu1: cpufreq_init: failed to get clk: -2
[    1.509893] sdhci: Secure Digital Host Controller Interface driver
[    1.519688] sdhci: Copyright(c) Pierre Ossman
[    1.527657] sdhci-pltfm: SDHCI platform and OF driver helper
[    1.537919] sdhci-esdhc-imx 30b40000.usdhc: Got CD GPIO
[    1.609591] mmc1: SDHCI controller on 30b40000.usdhc [30b40000.usdhc] using ADMA
[    1.679410] mmc0: SDHCI controller on 30b60000.usdhc [30b60000.usdhc] using ADMA
[    1.697114] caam 30900000.caam: can't identify CAAM mem clk: -2
[    1.706921] caam: probe of 30900000.caam failed with error -2
[    1.717513] hidraw: raw HID events driver (C) Jiri Kosina
[    1.726848] usbcore: registered new interface driver usbhid
[    1.736182] usbhid: USB HID core driver
[    1.744552] OF: graph: no port node found in /soc/etf@30084000
[    1.759744] OF: graph: no port node found in /soc/etr@30086000
[    1.762509] mmc1: new high speed SDHC card at address 1234
[    1.769772] OF: graph: no port node found in /soc/tpiu@30087000
[    1.782481] mmcblk1: mmc1:1234 SA16G 14.5 GiB
[    1.788702] OF: graph: no port node found in /soc/funnel@30041000
[    1.806500] OF: graph: no port node found in /soc/funnel@30083000
[    1.809589]  mmcblk1: p1
[    1.816916] OF: graph: no port node found in /soc/etm@3007c000
[    1.832191] coresight-etm3x 3007c000.etm: ETM 3.5 initialized
[    1.841833] OF: graph: no port node found in /soc/etm@3007d000
[    1.851559] coresight-etm3x 3007d000.etm: ETM 3.5 initialized
[    1.863219] sgtl5000 0-000a: sgtl5000 revision 0x11
[    1.873018] random: fast init done
[    1.882209] mmc0: new HS200 MMC card at address 0001
[    1.891263] mmcblk0: mmc0:0001 Q2J54A 3.64 GiB
[    1.899675] mmcblk0boot0: mmc0:0001 Q2J54A partition 1 2.00 MiB
[    1.909470] mmcblk0boot1: mmc0:0001 Q2J54A partition 2 2.00 MiB
[    1.919743]  mmcblk0: p1 p2
[    1.946516] fsl-sai 308a0000.sai: failed to get mclk0 clock: -2
[    1.956540] Netfilter messages via NETLINK v0.30.
[    1.964377] nfnl_acct: registering with nfnetlink.
[    1.972462] nf_conntrack version 0.5.0 (16384 buckets, 65536 max)
[    1.981902] nf_tables: (c) 2007-2009 Patrick McHardy <kaber@trash.net>
[    1.991950] ip_tables: (C) 2000-2006 Netfilter Core Team
[    2.001092] NET: Registered protocol family 10
[    2.009789] Segment Routing with IPv6
[    2.016734] ip6_tables: (C) 2000-2006 Netfilter Core Team
[    2.025468] NET: Registered protocol family 17
[    2.033174] Bridge firewalling registered
[    2.040410] 8021q: 802.1Q VLAN Support v1.8
[    2.047804] Key type dns_resolver registered
[    2.061614] Registering SWP/SWPB emulation handler
[    2.070125] registered taskstats version 1

Could you please check if clock frequency is changing when you take imx7d colibri module, burn on it BSP-5.0 reference image, and try to set display clock to another value using command like:

fbset -t 14065 70 70 10 10 20 3

6

I would advice to use BSP 5.1 which we are just about to release now. There, I do know that parallel RGB does work on any and all BSP flavours and Colibri iMX7 module SKUs.

7

I would advice to use BSP 5.1 which we are just about to release now

OK, I am going to try, thank You

8

@marcel.tx
LCDif also doesn’t work with BSP 5.1

Tried images from:

Commands that I’ve used to set desired screen resolution:

fbset -t 14065 70 70 10 10 20 3

fbset -g 1280 800 1280 800 16

1| BSP 3.0 Linux LXDE Image 2.8b6 :
Linux version 4.14.159-3.0.3+gfff496c2a1bd

OK - lcdif works, measured LCD clock frequency ~71 MHz

2| BSP 5.0 Linux Reference Multimedia Downstream SoC vendor based kernel Wayland/XWayland graphics back-end included 5.0.0

Linux version 5.4.47-5.0.0+git.9e7307657fc1

NOT OK - screen is black, only backlight works, measured LCD clock frequency ~24,1 MHz

3| Linux Reference Multimedia Downstream SoC vendor based kernel
Wayland/XWayland graphics back-end included 5.1.0-devel-202012

Linux version 5.4.77-5.1.0-devel+git.8fc7bd5da76f

NOT OK - screen is black, only backlight works, measured LCD clock frequency ~24,1 MHz

mxsfb driver is broken on kernel 5.4

9

fbset -t 14065 70 70 10 10 20 3
fbset -g 1280 800 1280 800 16

I don’t know how/why you would think that one could do it that way.

Anyway, please have a look at the following article on our developer website. Plus please try the just now released BSP 5.1 aka Colibri-iMX7-eMMC_Reference-Multimedia-Image-Tezi_5.1.0+build.4.tar.

10

I don’t know how/why you would think that one could do it that way.
This is the easiest way to change LCD timings/resolutioin when system runs and it works on older kernel, but not on 5.4.
It even works in Toradex easy installer, but need to restart tezi after setting proper resolution

Anyway, please have a look at the following article on our developer website.
I’ve read this article several times.
Setting display timings from u-boot using commands:

setenv vidargs video=‘mxsfb:1280x800M-16@60’

saveenv

Gives no effect on the display, only fbset outout changes from default:

mode "640x480-60"
        # D: 25.176 MHz, H: 31.469 kHz, V: 59.942 Hz
        geometry 640 480 640 480 16
        timings 39721 40 24 32 11 96 2
        accel false
        rgba 5/11,6/5,5/0,0/0
endmode

to

mode "1280x800-60"
        # D: 83.500 MHz, H: 49.703 kHz, V: 59.811 Hz
        geometry 1280 800 1280 800 16
        timings 11976 200 72 22 3 128 6
        accel false
        rgba 5/11,6/5,5/0,0/0
endmode

Please try the just now released BSP 5.1 aka: Colibri-iMX7-eMMC_Reference-Multimedia-Image-Tezi_5.1.0+build.4.tar

I am not sure where to download exacly that file. I’have downloaded image tezi image from:

https://artifacts.toradex.com/artifactory/tdxref-oe-prerelease-frankfurt/dunfell-5.x.y/monthly/5/colibri-imx7-emmc/tdx-xwayland/tdx-reference-multimedia-image/teziimage/

But it still does not work. Clock signal: ~24MHz
Imgur

Here is a photo when running BSP 3.0 reference image:
Imgur

clock signal: ~83MHz

11

@marcel.tx @stefan_e.tx

Ok, I moved to mxsfb_drm driver(it will be used in the future).

It is need to reconfigure clocks in device-tree otherwise kernel won’t boot

&lcdif: {
	clocks = <&clks IMX7D_LCDIF_PIXEL_ROOT_CLK>,
	              <&clks IMX7D_LCDIF_PIXEL_ROOT_CLK>;
	clock-names = "pix", "axi";
};

Display still doesn’t works but it is possible to get detailed debug log with bootarg parameter:

drm.debug=0x1ff

[    0.000000] Kernel command line: root=/dev/mmcblk0p1 rw rootwait console=ttymxc0,115200n8 drm.debug=0x1ff
[    0.872502] [drm:drm_core_init] Initialized
[    2.064909] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[    2.071561] [drm] No driver support for vblank timestamp query.
[    2.089586] [drm:drm_irq_install] irq=50
[    2.089687] [drm:drm_minor_register]
[    2.089709] [drm:drm_minor_register]
[    2.091014] [drm:drm_minor_register] new minor registered 0
[    2.091162] [drm:drm_sysfs_connector_add] adding "DPI-1" to sysfs
[    2.091193] [drm:drm_sysfs_hotplug_event] generating hotplug event
[    2.091233] [drm] Initialized mxsfb-drm 1.0.0 20160824 for 30730000.lcdif on minor 0
[    2.100405] [drm:drm_client_modeset_probe]
[    2.100423] [drm:drm_mode_object_get] OBJ ID: 31 (2)
[    2.100439] [drm:drm_helper_probe_single_connector_modes] [CONNECTOR:31:DPI-1]
[    2.100454] [drm:drm_helper_probe_single_connector_modes] [CONNECTOR:31:DPI-1] status updated from unknown to connected
[    2.100496] [drm:drm_sysfs_hotplug_event] generating hotplug event
[    2.106317] [drm:drm_helper_probe_single_connector_modes] [CONNECTOR:31:DPI-1] probed modes :
[    2.106340] [drm:drm_mode_debug_printmodeline] Modeline "1280x800": 60 71000 1280 1350 1360 1380 800 870 880 883 0x48 0xa
[    2.106352] [drm:drm_client_modeset_probe] connector 31 enabled? yes
[    2.106365] [drm:drm_client_modeset_probe] Not using firmware configuration
[    2.106377] [drm:drm_client_modeset_probe] looking for cmdline mode on connector 31
[    2.106386] [drm:drm_client_modeset_probe] looking for preferred mode on connector 31 0
[    2.106393] [drm:drm_client_modeset_probe] found mode 1280x800
[    2.106401] [drm:drm_client_modeset_probe] picking CRTCs for 65535x65535 config
[    2.106417] [drm:drm_client_modeset_probe] desired mode 1280x800 set on crtc 33 (0,0)
[    2.106428] [drm:drm_mode_object_get] OBJ ID: 31 (2)
[    2.106437] [drm:drm_mode_object_put.part.0] OBJ ID: 31 (3)
[    2.106450] [drm:__drm_fb_helper_initial_config_and_unlock] test CRTC 0 primary plane
[    2.106464] [drm:drm_fb_helper_generic_probe] surface width(1280), height(800) and bpp(32)
[    2.110524] [drm:drm_mode_addfb2] [FB:35]
[    2.110539] [drm:drm_mode_object_put.part.0] OBJ ID: 35 (2)
[    2.116911] [drm:drm_atomic_state_init] Allocated atomic state (ptrval)
[    2.116930] [drm:drm_atomic_get_plane_state] Added [PLANE:32:plane-0] (ptrval) state to (ptrval)
[    2.116945] [drm:drm_atomic_get_crtc_state] Added [CRTC:33:crtc-0] (ptrval) state to (ptrval)
[    2.116967] [drm:drm_atomic_set_mode_for_crtc] Set [MODE:1280x800] for [CRTC:33:crtc-0] state (ptrval)
[    2.116978] [drm:drm_atomic_set_crtc_for_plane] Link [PLANE:32:plane-0] state (ptrval) to [CRTC:33:crtc-0]
[    2.116989] [drm:drm_atomic_set_fb_for_plane] Set [FB:35] for [PLANE:32:plane-0] state (ptrval)
[    2.116998] [drm:drm_mode_object_get] OBJ ID: 35 (1)
[    2.117010] [drm:drm_atomic_add_affected_connectors] Adding all current connectors for [CRTC:33:crtc-0] to (ptrval)
[    2.117024] [drm:drm_mode_object_get] OBJ ID: 31 (2)
[    2.117033] [drm:drm_atomic_get_connector_state] Added [CONNECTOR:31:DPI-1] (ptrval) state to (ptrval)
[    2.117041] [drm:drm_mode_object_get] OBJ ID: 31 (3)
[    2.117050] [drm:drm_atomic_set_crtc_for_connector] Link [CONNECTOR:31:DPI-1] state (ptrval) to [CRTC:33:crtc-0]
[    2.117057] [drm:drm_atomic_check_only] checking (ptrval)
[    2.117075] [drm:drm_atomic_helper_check_modeset] [CRTC:33:crtc-0] mode changed
[    2.117083] [drm:drm_atomic_helper_check_modeset] [CRTC:33:crtc-0] enable changed
[    2.117092] [drm:drm_atomic_helper_check_modeset] [CRTC:33:crtc-0] active changed
[    2.117106] [drm:drm_atomic_helper_check_modeset] Updating routing for [CONNECTOR:31:DPI-1]
[    2.117121] [drm:drm_atomic_helper_check_modeset] [CONNECTOR:31:DPI-1] using [ENCODER:34:None-34] on [CRTC:33:crtc-0]
[    2.117132] [drm:drm_atomic_helper_check_modeset] [CRTC:33:crtc-0] needs all connectors, enable: y, active: y
[    2.117141] [drm:drm_atomic_add_affected_connectors] Adding all current connectors for [CRTC:33:crtc-0] to (ptrval)
[    2.117151] [drm:drm_atomic_add_affected_planes] Adding all current planes for [CRTC:33:crtc-0] to (ptrval)
[    2.117175] [drm:drm_atomic_add_affected_planes] Adding all current planes for [CRTC:33:crtc-0] to (ptrval)
[    2.117183] [drm:drm_atomic_commit] committing (ptrval)
[    2.117216] [drm:drm_atomic_helper_commit_modeset_disables] modeset on [ENCODER:34:None-34]
[    2.117226] [drm:drm_atomic_helper_commit_modeset_enables] enabling [CRTC:33:crtc-0]
[    2.117297] mxsfb 30730000.lcdif: [drm:mxsfb_set_pixel_fmt [mxsfb]] Setting up XR24 little-endian (0x34325258) mode
[    2.117415] mxsfb 30730000.lcdif: [drm:mxsfb_crtc_enable [mxsfb]] Pixel clock: 71000kHz (actual: 24000kHz)
[    2.117433] mxsfb 30730000.lcdif: [drm:mxsfb_crtc_enable [mxsfb]] Connector bus_flags: 0x00000006
[    2.117450] mxsfb 30730000.lcdif: [drm:mxsfb_crtc_enable [mxsfb]] Mode flags: 0x0000000A
[    2.117469] mxsfb 30730000.lcdif: [drm:mxsfb_crtc_enable [mxsfb]] Using bus_format: 0x0000100A
[    2.117491] [drm:drm_atomic_helper_commit_modeset_enables] enabling [ENCODER:34:None-34]
[    2.117515] [drm:drm_atomic_state_default_clear] Clearing atomic state (ptrval)
[    2.117526] [drm:drm_mode_object_put.part.0] OBJ ID: 31 (4)
[    2.117536] [drm:__drm_atomic_state_free] Freeing atomic state (ptrval)
[    2.117614] [drm:drm_atomic_state_init] Allocated atomic state (ptrval)
[    2.117624] [drm:drm_mode_object_get] OBJ ID: 35 (2)
[    2.117633] [drm:drm_atomic_get_plane_state] Added [PLANE:32:plane-0] (ptrval) state to (ptrval)
[    2.117642] [drm:drm_mode_object_get] OBJ ID: 36 (1)
[    2.117650] [drm:drm_atomic_get_crtc_state] Added [CRTC:33:crtc-0] (ptrval) state to (ptrval)
[    2.117665] [drm:drm_atomic_set_fb_for_plane] Set [FB:35] for [PLANE:32:plane-0] state (ptrval)
[    2.117672] [drm:drm_mode_object_get] OBJ ID: 35 (3)
[    2.117680] [drm:drm_mode_object_put.part.0] OBJ ID: 35 (4)
[    2.117689] [drm:drm_atomic_add_affected_connectors] Adding all current connectors for [CRTC:33:crtc-0] to (ptrval)
[    2.117700] [drm:drm_mode_object_get] OBJ ID: 31 (4)
[    2.117707] [drm:drm_mode_object_get] OBJ ID: 31 (5)
[    2.117714] [drm:drm_atomic_get_connector_state] Added [CONNECTOR:31:DPI-1] (ptrval) state to (ptrval)
[    2.117723] [drm:drm_mode_object_put.part.0] OBJ ID: 31 (5)
[    2.117732] [drm:drm_atomic_set_crtc_for_connector] Link [CONNECTOR:31:DPI-1] state (ptrval) to [NOCRTC]
[    2.117740] [drm:drm_mode_object_get] OBJ ID: 31 (4)
[    2.117750] [drm:drm_atomic_set_crtc_for_connector] Link [CONNECTOR:31:DPI-1] state (ptrval) to [CRTC:33:crtc-0]
[    2.117756] [drm:drm_atomic_check_only] checking (ptrval)
[    2.117773] [drm:drm_atomic_helper_check_modeset] Updating routing for [CONNECTOR:31:DPI-1]
[    2.117786] [drm:drm_atomic_helper_check_modeset] [CONNECTOR:31:DPI-1] keeps [ENCODER:34:None-34], now on [CRTC:33:crtc-0]
[    2.117800] [drm:drm_atomic_add_affected_planes] Adding all current planes for [CRTC:33:crtc-0] to (ptrval)
[    2.117807] [drm:drm_atomic_commit] committing (ptrval)
[    2.117841] [drm:drm_atomic_state_default_clear] Clearing atomic state (ptrval)
[    2.117850] [drm:drm_mode_object_put.part.0] OBJ ID: 31 (5)
[    2.117857] [drm:drm_mode_object_put.part.0] OBJ ID: 31 (4)
[    2.117865] [drm:drm_mode_object_put.part.0] OBJ ID: 36 (2)
[    2.117874] [drm:drm_mode_object_put.part.0] OBJ ID: 35 (3)
[    2.117880] [drm:__drm_atomic_state_free] Freeing atomic state (ptrval)
[    2.139711] [drm:drm_atomic_state_init] Allocated atomic state (ptrval)
[    2.139727] [drm:drm_mode_object_get] OBJ ID: 35 (2)
[    2.139738] [drm:drm_atomic_get_plane_state] Added [PLANE:32:plane-0] (ptrval) state to (ptrval)
[    2.139749] [drm:drm_mode_object_get] OBJ ID: 36 (1)
[    2.139758] [drm:drm_atomic_get_crtc_state] Added [CRTC:33:crtc-0] (ptrval) state to (ptrval)
[    2.139778] [drm:drm_atomic_set_fb_for_plane] Set [FB:35] for [PLANE:32:plane-0] state (ptrval)
[    2.139785] [drm:drm_mode_object_get] OBJ ID: 35 (3)
[    2.139792] [drm:drm_mode_object_put.part.0] OBJ ID: 35 (4)
[    2.139804] [drm:drm_atomic_add_affected_connectors] Adding all current connectors for [CRTC:33:crtc-0] to (ptrval)
[    2.139817] [drm:drm_mode_object_get] OBJ ID: 31 (4)
[    2.139825] [drm:drm_mode_object_get] OBJ ID: 31 (5)
[    2.139833] [drm:drm_atomic_get_connector_state] Added [CONNECTOR:31:DPI-1] (ptrval) state to (ptrval)
[    2.139842] [drm:drm_mode_object_put.part.0] OBJ ID: 31 (5)
[    2.139852] [drm:drm_atomic_set_crtc_for_connector] Link [CONNECTOR:31:DPI-1] state (ptrval) to [NOCRTC]
[    2.139861] [drm:drm_mode_object_get] OBJ ID: 31 (4)
[    2.139871] [drm:drm_atomic_set_crtc_for_connector] Link [CONNECTOR:31:DPI-1] state (ptrval) to [CRTC:33:crtc-0]
[    2.139878] [drm:drm_atomic_check_only] checking (ptrval)
[    2.139903] [drm:drm_atomic_helper_check_modeset] Updating routing for [CONNECTOR:31:DPI-1]
[    2.139918] [drm:drm_atomic_helper_check_modeset] [CONNECTOR:31:DPI-1] keeps [ENCODER:34:None-34], now on [CRTC:33:crtc-0]
[    2.139941] [drm:drm_atomic_add_affected_planes] Adding all current planes for [CRTC:33:crtc-0] to (ptrval)
[    2.139950] [drm:drm_atomic_commit] committing (ptrval)
[    2.140009] [drm:drm_atomic_state_default_clear] Clearing atomic state (ptrval)
[    2.140019] [drm:drm_mode_object_put.part.0] OBJ ID: 31 (5)
[    2.140028] [drm:drm_mode_object_put.part.0] OBJ ID: 31 (4)
[    2.140036] [drm:drm_mode_object_put.part.0] OBJ ID: 36 (2)
[    2.140047] [drm:drm_mode_object_put.part.0] OBJ ID: 35 (3)
[    2.140054] [drm:__drm_atomic_state_free] Freeing atomic state (ptrval)
[    2.164867] mxsfb 30730000.lcdif: fb0: mxsfb-drmdrmfb frame buffer device
[    7.807987] [drm:drm_atomic_state_init] Allocated atomic state (ptrval)
[    7.808008] [drm:drm_mode_object_get] OBJ ID: 35 (2)
[    7.808019] [drm:drm_atomic_get_plane_state] Added [PLANE:32:plane-0] (ptrval) state to (ptrval)
[    7.808031] [drm:drm_mode_object_get] OBJ ID: 36 (1)
[    7.808040] [drm:drm_atomic_get_crtc_state] Added [CRTC:33:crtc-0] (ptrval) state to (ptrval)
[    7.808060] [drm:drm_atomic_set_fb_for_plane] Set [FB:35] for [PLANE:32:plane-0] state (ptrval)
[    7.808067] [drm:drm_mode_object_get] OBJ ID: 35 (3)
[    7.808075] [drm:drm_mode_object_put.part.0] OBJ ID: 35 (4)
[    7.808087] [drm:drm_atomic_add_affected_connectors] Adding all current connectors for [CRTC:33:crtc-0] to (ptrval)
[    7.808101] [drm:drm_mode_object_get] OBJ ID: 31 (4)
[    7.808108] [drm:drm_mode_object_get] OBJ ID: 31 (5)
[    7.808117] [drm:drm_atomic_get_connector_state] Added [CONNECTOR:31:DPI-1] (ptrval) state to (ptrval)
[    7.808126] [drm:drm_mode_object_put.part.0] OBJ ID: 31 (5)
[    7.808135] [drm:drm_atomic_set_crtc_for_connector] Link [CONNECTOR:31:DPI-1] state (ptrval) to [NOCRTC]
[    7.808144] [drm:drm_mode_object_get] OBJ ID: 31 (4)
[    7.808153] [drm:drm_atomic_set_crtc_for_connector] Link [CONNECTOR:31:DPI-1] state (ptrval) to [CRTC:33:crtc-0]
[    7.808160] [drm:drm_atomic_check_only] checking (ptrval)
[    7.808184] [drm:drm_atomic_helper_check_modeset] Updating routing for [CONNECTOR:31:DPI-1]
[    7.808199] [drm:drm_atomic_helper_check_modeset] [CONNECTOR:31:DPI-1] keeps [ENCODER:34:None-34], now on [CRTC:33:crtc-0]
[    7.808221] [drm:drm_atomic_add_affected_planes] Adding all current planes for [CRTC:33:crtc-0] to (ptrval)
[    7.808230] [drm:drm_atomic_commit] committing (ptrval)
[    7.808289] [drm:drm_atomic_state_default_clear] Clearing atomic state (ptrval)
[    7.808299] [drm:drm_mode_object_put.part.0] OBJ ID: 31 (5)
[    7.808308] [drm:drm_mode_object_put.part.0] OBJ ID: 31 (4)
[    7.808317] [drm:drm_mode_object_put.part.0] OBJ ID: 36 (2)
[    7.808327] [drm:drm_mode_object_put.part.0] OBJ ID: 35 (3)
[    7.808334] [drm:__drm_atomic_state_free] Freeing atomic state (ptrval)

The most interesting line is:

[    2.117415] mxsfb 30730000.lcdif: [drm:mxsfb_crtc_enable [mxsfb]] Pixel clock: 71000kHz (actual: 24000kHz)

Inside driver code pixel clock is set here

clk_set_rate(mxsfb->clk, m->crtc_clock * 1000);

https://git.toradex.com/cgit/linux-toradex.git/tree/drivers/gpu/drm/mxsfb/mxsfb_crtc.c?h=toradex_5.4-2.1.x-imx#n356

And the new frequency is never set for unknown reason. It always is 24Mhz

cat /sys/kernel/debug/clk/clk_summary

                                 enable  prepare  protect                                duty
   clock                          count    count    count        rate   accuracy phase  cycle
---------------------------------------------------------------------------------------------

    lcdif_pixel_src                   1        1        0    24000000          0     0  50000
       lcdif_pixel_cg                 1        1        0    24000000          0     0  50000
          lcdif_pixel_pre_div         1        1        0    24000000          0     0  50000
             lcdif_pixel_post_div       1        1        0    24000000          0     0  50000
                lcdif_pixel_root_clk       2        2        0    24000000          0     0  50000

When using old driver(mxsfb.c) it is the same - pixel clock is never set.
It is probably bug in clk subsystem

12

I can confirm that this bug is connected with clocks setup. That is the main reason why both old mxsfb.c and the new mxsfb_drm.c drivers didn’t work on imx7d:

LCD clocks hierarchy in 4.14 kernel:

    pll_video_main_src                    1            1    24000000          0 0
       pll_video_main                     1            1   853176000          0 0
          pll_video_main_bypass           1            1   853176000          0 0
             pll_video_test_div           1            1   213294000          0 0
                pll_video_main_clk           1            1   213294000          0 0
                   pll_video_post_div           1            1   213294000          0 0
                      lcdif_pixel_src           1            1   213294000          0 0
                         lcdif_pixel_cg           1            1   213294000          0 0
                            lcdif_pixel_pre_div           1            1    71098000          0 0
                               lcdif_pixel_post_div           1            1    71098000          0 0
                                  lcdif_pixel_root_clk           1            1    71098000          0 0

LCD clocks hierarchy in 5.4 kernel is divided into two groups:

    pll_video_main                    0        0        0   656600000          0     0  50000
       pll_video_main_bypass          0        0        0   656600000          0     0  50000
          pll_video_main_clk          0        0        0   656600000          0     0  50000
             pll_video_test_div       0        0        0   164150000          0     0  50000
                pll_video_post_div       0        0        0   164150000          0     0  50000

    lcdif_pixel_src                   1        1        0    24000000          0     0  50000
       lcdif_pixel_cg                 1        1        0    24000000          0     0  50000
          lcdif_pixel_pre_div         1        1        0    24000000          0     0  50000
             lcdif_pixel_post_div       1        1        0    24000000          0     0  50000
                lcdif_pixel_root_clk       2        2        0    24000000          0     0  50000

Inside kernel 4.14 IMX7D_PLL_VIDEO_POST_DIV was parent of IMX7D_LCDIF_PIXEL_ROOT_SRC

	/* set lcdif pixel root clock source to get the required 33Mhz clock */
	imx_clk_set_parent(clks[IMX7D_LCDIF_PIXEL_ROOT_SRC], clks[IMX7D_PLL_VIDEO_POST_DIV]);

https://git.toradex.com/cgit/linux-toradex.git/tree/drivers/clk/imx/clk-imx7d.c?h=toradex_4.14-2.3.x-imx

In kernel 5.4 IMX7D_LCDIF_PIXEL_ROOT_SRC has no parent

https://git.toradex.com/cgit/linux-toradex.git/tree/drivers/clk/imx/clk-imx7d.c?h=toradex_5.4-2.1.x-imx

I have created a patch with line:

clk_set_parent(hws[IMX7D_LCDIF_PIXEL_ROOT_SRC]->clk, hws[IMX7D_PLL_VIDEO_POST_DIV]->clk);

but kernel won’t boot after applying it.

It boots up, and LCD is almost working(bad colors, pixel clock is around 68MHz) if I use IMX7D_PLL_SYS_PFD5_CLK timer as a parent

@marcel.tx @stefan_e.tx
Could you contact with more expirienced Linux developer and point out this issue?

13

Hi @qba

Can you try to modify your devicetree as follows:

 &lcdif {
         lcd-supply = <&reg_3v3>;
         status = "okay";
         assigned-clocks = <&clks IMX7D_LCDIF_PIXEL_ROOT_SRC>;
         assigned-clock-parents = <&clks IMX7D_PLL_VIDEO_POST_DIV>;

     
     port {
         lcdif_out: endpoint {
             remote-endpoint = <&panel_in>;
         };
     };
 };

I would expect this should change the clock parent of the pixel src to the pll video post clock again. And then hopefully this frequency would be possible.

Regards,
Stefan

14

Hi @stefan_e.tx
Unfortunnatelly kernel won’t boot with these changes only.
But I modified clocks node, now kernel boots and LCDIF finally works!, also my kernel patch is unnecessary

Here is my devicetree node(Currently I am using mxs_drm driver):

&lcdif {
	pinctrl-names = "default";
	pinctrl-0 = <&pinctrl_lcdif_dat &pinctrl_lcdif_ctrl>;

	clocks = <&clks IMX7D_LCDIF_PIXEL_ROOT_CLK>,
		      <&clks IMX7D_LCDIF_PIXEL_ROOT_CLK>;
	clock-names = "pix", "axi"; 

	assigned-clocks = <&clks IMX7D_LCDIF_PIXEL_ROOT_SRC>;
	assigned-clock-parents = <&clks IMX7D_PLL_VIDEO_POST_DIV>;
	status = "okay";

	port {
		lcdif_out: endpoint {
			remote-endpoint = <&panel_in>;
		};
	};
};

The clock still is not correct (~54MHz) but image quality is OK

[    1.778687] mxsfb 30730000.lcdif: [drm:mxsfb_crtc_enable] Pixel clock: 71000kHz (actual: 54716kHz)

Current clock hierarchy looks like this:

pll_video_main                    1        1        1   656600000          0     0  50000
       pll_video_main_bypass          1        1        1   656600000          0     0  50000
          pll_video_main_clk          1        1        1   656600000          0     0  50000
             pll_video_test_div       1        1        2   164150000          0     0  50000
                pll_video_post_div       1        1        1   164150000          0     0  50000
                   lcdif_pixel_src       1        1        0   164150000          0     0  50000
                      lcdif_pixel_cg       1        1        0   164150000          0     0  50000
                         lcdif_pixel_pre_div       1        1        0    54716667          0     0  50000
                            lcdif_pixel_post_div       1        1        0    54716667          0     0  50000
                               lcdif_pixel_root_clk       2        2        0    54716667          0     0  50000

For me It is OK, but I am not sure if it is the final solution. Please fix this issue in Toradex BSP.
Thank You very much for your help

15

Thanks for the feedback. Strange that the axi clock is required… I thought that is not necessary for iMX7.

I don’t know where this clock parent change comes from (maybe U-Boot?) and it isn’t a bug per se. It’s just that higher pixel clocks are not possible with this parent clock. I don’t know why they decided to do that. I will leave that decision to @marcel.tx to decide if they want to change it in the BSP.

Regards,
Stefan