Samsung Galaxy S4 stuck at loading screen

@calasso wrote in !1668 (comment 94170252):

I am having problems with my device, after flashing postmarketOS, I can only access the ssh through the data cable, and when I connect the device quickly appears the boot screen and then turns black. Does this occur because of having multiple variants for [Samsung Galaxy S4]?

Thank you for reporting this issue. Some follow up questions:

• Which model of the S4 do you have?
• Did you flash the kernel and rootfs?
• How did you flash the rootfs (with pmbootstrap flasher flash_rootfs, recovery zip, ...?)
• Which UI have you selected?
• What's the output of logread after logging in with SSH?

mentioned in merge request !1668 (merged)

By Oliver Smith on 2018-08-16T16:49:32

Which S4 model do you have?

• Samsung i9505

Did you flash the kernel and rootfs?

• Yes

How did you flash the rootfs (with pmbootstrap flash_rootfs, recovery zip, ...?)

• Pmbootstrap flash_rootfs

Which user interface did you select?

• Plasma-mobile

What is the output of logread after login with SSH?

Dec 31 23:59:59 raiocelular auth.info sshd [5672]: Password accepted for calasso of 172.16.42.2 port 49988 ssh2

I've attached the log so I can check it out.

logread_i9505

By Luiz Carlos Calasso on 2018-08-19T16:36:53

Thank you for answering these questions and for attaching the log. Plasma Mobile is known to have problems with Android framebuffer drivers (other interfaces should work with it though, see the photos in the device's wiki page). This is the important part of your log file:

Dec 31 23:59:59 raiocelular user.notice calasso:plasma-mobile: kwin_core: Could not take device /dev/fb3 , cause:  "Failed to get file descriptor for device"                                                     
Dec 31 23:59:59 raiocelular user.notice calasso:plasma-mobile: kwin_wayland_framebuffer: Using frame buffer device: "/dev/fb3"                                                                                    
Dec 31 23:59:59 raiocelular user.notice calasso:plasma-mobile: kwin_wayland_framebuffer: Failed to open frame buffer device: "/dev/fb3" through logind, trying without                                            
Dec 31 23:59:59 raiocelular user.notice calasso:plasma-mobile: kwin_wayland_framebuffer: Bits Per Pixel:  32                                                                                                      
Dec 31 23:59:59 raiocelular user.notice calasso:plasma-mobile: kwin_wayland_framebuffer: Buffer Length:  0                                                                                                        
Dec 31 23:59:59 raiocelular user.notice calasso:plasma-mobile: kwin_wayland_framebuffer: Bytes Per Line:  0                                                                                                       
Dec 31 23:59:59 raiocelular user.notice calasso:plasma-mobile: kwin_wayland_framebuffer: Alpha Length:  8                                                                                                         
Dec 31 23:59:59 raiocelular user.notice calasso:plasma-mobile: kwin_wayland_framebuffer: Red Length:  8                                                                                                           
Dec 31 23:59:59 raiocelular user.notice calasso:plasma-mobile: kwin_wayland_framebuffer: Green Length:  8                                                                                                         
Dec 31 23:59:59 raiocelular user.notice calasso:plasma-mobile: kwin_wayland_framebuffer: Blue Length:  8                                                                                                          
Dec 31 23:59:59 raiocelular user.notice calasso:plasma-mobile: kwin_wayland_framebuffer: Blue Offset:  16                                                                                                         
Dec 31 23:59:59 raiocelular user.notice calasso:plasma-mobile: kwin_wayland_framebuffer: Green Offset:  8                                                                                                         
Dec 31 23:59:59 raiocelular user.notice calasso:plasma-mobile: kwin_wayland_framebuffer: Red Offset:  0                                                                                                           
Dec 31 23:59:59 raiocelular user.notice calasso:plasma-mobile: kwin_wayland_framebuffer: Alpha Offset:  24                                                                                                        
Dec 31 23:59:59 raiocelular user.notice calasso:plasma-mobile: kwin_wayland_framebuffer: Framebuffer format is RGBA8888                                                                                           
Dec 31 23:59:59 raiocelular user.notice calasso:plasma-mobile: kwin_core: Compositing forced to QPainter mode by environment variable                                                                             
Dec 31 23:59:59 raiocelular user.notice calasso:plasma-mobile: kwin_core: Forcing EGL native interface as Qt uses OpenGL ES                                                                                       
Dec 31 23:59:59 raiocelular user.notice calasso:plasma-mobile: kwin_wayland_framebuffer: Failed to mmap frame buffer                                                                                              
Dec 31 23:59:59 raiocelular daemon.warn console-kit-daemon[1308]: WARNING: ck_device_set_active: Device type not supported                                                                                        
Dec 31 23:59:59 raiocelular daemon.warn console-kit-daemon[1308]: WARNING: failed to unmute FD with KDSKBMUTE 

The first 3 lines are expected, because we don't use logind (from systemd) in postmarketOS, so it can't open the framebuffer that way. The last three lines are the fatal ones, it seems that consolekit2 (ck) "does not support the device type" (whatever that means, maybe we need to add a mapping for the framebuffer type or something).

@calasso: to get this working, the next step would be digging into the consolekit2 source code and finding where the "Device type not supported" message originates from (e.g. with grep). Would you like to investigate that?

The best fix would be mainlining your device, but that is a whole lot more effort.

@PureTryOut, @bshah: in the back of my head I had that Plasma Mobile won't work on armhf on postmarketOS in general, except with mainline devices. But I can't find an issue that says so, there's only #878 (closed) (where we implemented a workaround, so the qt5-qtdeclarative aport gets compiled for armv7).

• So if consolekit2 and kwin played along with the Android framebuffer drivers nicely, then it should work in theory, right? Or am I missing something?
• I know that it will be slow, but it would be nice if it could at least be started. Is there anything we can do to improve speed on devices without hardware acceleration, like disabling animations and effects?

By Oliver Smith on 2018-08-19T20:23:14

mentioned in commit wiki@a2c0db2c

By postmarketOS Wiki bot on 2018-08-19T20:42:35

I remember Plasma Mobile on armhf only working if the device in question has hardware acceleration (it's in the $pkgdesc of postmarketos-ui-plasma-mobile as well). I'm not entirely sure how I/we got to that conclusion, but basically it means that right now it'll only run on (at least partially) mainlined devices, as those are the only ones we have hardware acceleration working for.

By Bart Ribbers on 2018-08-19T22:41:28

@ollieparanoid I'm going to do the tests you asked for, it may take a while because I do not have much time because of the work and the college that I do at night, when I get results, I'll keep you informed. I was able to use another interface, Xfce4 and also picked up the black screen, when initializing the logo appears quickly and then it disappears. I did this test first to find out if it was interface problem.

By Luiz Carlos Calasso on 2018-08-20T13:48:52

moved to pmaports#34 (closed)

By Bart Ribbers on 2018-09-17T21:42:40