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by timg236
Wed Sep 02, 2020 11:02 am
Forum: Bare metal, Assembly language
Topic: Circle - C++ bare metal environment (with USB)
Replies: 297
Views: 90849

Re: Circle - C++ bare metal environment (with USB)

Have you had any luck finding a VL805 datasheet ? Or documentation from RPi on how they have used it ? The VL805 is a standard xHCI 1.0 controller. The current revision 1.2 of the xHCI specification is here . i believe it emulates the xHCI standard after it has executed its firmware but any time yo...
by timg236
Wed Sep 02, 2020 6:20 am
Forum: General discussion
Topic: How to update VL805 and bootloader unattended/automatically?
Replies: 12
Views: 758

Re: How to update VL805 and bootloader unattended/automatically?

You don't need to do anything, the bootloader would only update the EEPROM if the image was different. Rather than rolling your own update method, a method commonly used for automated installs is to create your own firmware folder containing the files of interest /lib/firmware/raspberry/bootloader/k...
by timg236
Tue Sep 01, 2020 12:48 pm
Forum: General discussion
Topic: Serious Problem in Bootloader EEPROM
Replies: 23
Views: 1556

Re: Serious Problem in Bootloader EEPROM

The checksum is generated on-the-fly by the script. Which means, should the firmware file be corrupted, the checksum generated will still match and the corrupted file will be flashed. AIUI the checksum is merely to verify that a pieeprom.bin is a Boot Eeprom image and not just some random file plac...
by timg236
Mon Aug 31, 2020 5:52 pm
Forum: General discussion
Topic: Serious Problem in Bootloader EEPROM
Replies: 23
Views: 1556

Re: Serious Problem in Bootloader EEPROM

Simple test case on a stock, unmodified system: 1. With an SD card present but while booted from USB, change BOOT_ORDER to 0xf41. 2. Reboot. 3. When the SD card runs, change the BOOT_ORDER to 0xf14. 4. Reboot. You're in an endless reprogramming loop. Well done you've created a loop - don't do that....
by timg236
Mon Aug 31, 2020 5:23 pm
Forum: General discussion
Topic: Serious Problem in Bootloader EEPROM
Replies: 23
Views: 1556

Re: Serious Problem in Bootloader EEPROM

If you hadn't disabled step (1) then this would not have happened "5. Observe that in /boot, recovery.bin has been renamed to recovery.000, but pieeprom.sig and pieeprom.upd are still present." The files would have been deleted so the problem would not have occurred. So I disagree with your assessme...
by timg236
Mon Aug 31, 2020 8:31 am
Forum: General discussion
Topic: Serious Problem in Bootloader EEPROM
Replies: 23
Views: 1556

Re: Serious Problem in Bootloader EEPROM

The mistake was "1. Disable the rpi-eeprom-update.service (I run this way to prevent automatic EEPROM updates):" This would have deleted the update files when the system booted. There's no need to rename the .upd files and you can't do that via TFTP anyway. If we change anything it would be to disab...
by timg236
Wed Aug 19, 2020 6:38 pm
Forum: Troubleshooting
Topic: Raspberry Pi 4 doesnt boot after apt full-upgrade
Replies: 36
Views: 2125

Re: Raspberry Pi 4 doesnt boot after apt full-upgrade

Would you be able to try this experimental firmware fix? https://drive.google.com/drive/folders/1jq6bdy1j-IB0_bODgID4sNi27tWrIu-5?usp=sharing Testing is looking good so far, RPi survived about 30 reboots. I'll keep an eye on it and see if I can make it fail. LibreELEC:/ # vcgencmd version Aug 19 20...
by timg236
Wed Aug 19, 2020 4:45 pm
Forum: Troubleshooting
Topic: Raspberry Pi 4 doesnt boot after apt full-upgrade
Replies: 36
Views: 2125

Re: Raspberry Pi 4 doesnt boot after apt full-upgrade

Would you be able to try this experimental firmware fix? https://drive.google.com/drive/folders/1jq6bdy1j-IB0_bODgID4sNi27tWrIu-5?usp=sharing What was the issue/fix? If I copy this files to /boot, can I upgrade normally (apt full-upgrade) firmware in future? There's a firmware tweak for a subtle ti...
by timg236
Wed Aug 19, 2020 3:49 pm
Forum: Troubleshooting
Topic: Raspberry Pi 4 doesnt boot after apt full-upgrade
Replies: 36
Views: 2125

Re: Raspberry Pi 4 doesnt boot after apt full-upgrade

melqui wrote:
Wed Aug 19, 2020 2:57 pm
Here Raspberry Pi 4B v1.2 4GB RAM
uSD Kingston Canvas Select 32GB or Sandisk Ultra 16GB
Thanks!
by timg236
Wed Aug 19, 2020 3:32 pm
Forum: Advanced users
Topic: Changing EEPROM configuration
Replies: 9
Views: 732

Re: Changing EEPROM configuration

You could probably create something like 'visudo' to apply an update after editing the config. Alternatively, for automatic changes to EEPROM config there is a hooks mechanism although since the config is migrated after an updated these both tend to be one-off tasks unless you are building custom OS...
by timg236
Wed Aug 19, 2020 2:51 pm
Forum: Troubleshooting
Topic: Raspberry Pi 4 doesnt boot after apt full-upgrade
Replies: 36
Views: 2125

Re: Raspberry Pi 4 doesnt boot after apt full-upgrade

BTW: earliest firmware with intermittent boot issues so far seems to be Jul 31 which failed to boot on second try - haven't noticed anything unusual yet on Jul 17 and before. so long, Hias I was able to reproduce something with similar symptoms but only with one board + SD combination. Which board(...
by timg236
Wed Aug 19, 2020 1:49 pm
Forum: Troubleshooting
Topic: Raspberry Pi 4 doesnt boot after apt full-upgrade
Replies: 36
Views: 2125

Re: Raspberry Pi 4 doesnt boot after apt full-upgrade

Thanks @HiassofT that's very useful
by timg236
Wed Aug 19, 2020 11:27 am
Forum: Troubleshooting
Topic: Raspberry Pi 4 doesnt boot after apt full-upgrade
Replies: 36
Views: 2125

Re: Raspberry Pi 4 doesnt boot after apt full-upgrade

If you see an intermittent issue please can you post 'vcgencmd version' and 'uname -a' here on the occasions where it does boot so that we can more accurately track versions with intermittent issues. Other information which might be relevant is the display(s) resolution and any overclocking settings...
by timg236
Thu Aug 13, 2020 9:03 am
Forum: Troubleshooting
Topic: PI 4 Won't boot, 1 green blink. Good bootloader
Replies: 15
Views: 632

Re: PI 4 Won't boot, 1 green blink. Good bootloader

It's booted and loaded the GPU firmware correctly, the problem is happening later on unless you are really unlucky and the SD-card works sometimes on boot. However, you now have USB boot enabled so you could use a USB boot Try adding "hdmi_safe=1" to config.txt https://www.raspberrypi.org/documentat...
by timg236
Tue Aug 11, 2020 11:00 pm
Forum: General discussion
Topic: RPi-eeprom 31/07/20 has gone stable
Replies: 17
Views: 1334

Re: RPi-eeprom 31/07/20 has gone stable

I think expecting a USB 3.0 device that works on a variety of X86 PCs to also work on the Pi is reasonable. For UASP support I would agree that it's not an unreasonable thing to expect, maybe there will fixes to the SATA adapter firmware for some adapters, others might be fixed via upstream Linux k...
by timg236
Tue Aug 11, 2020 10:09 pm
Forum: General discussion
Topic: RPi-eeprom 31/07/20 has gone stable
Replies: 17
Views: 1334

Re: RPi-eeprom 31/07/20 has gone stable

It just needs a little bit of time to be absolutely confident that there are no bad regressions i.e. we can't break SD boot, low level hardware setup etc. It's extremely unlikely that something would slip past CI -> beta -> stable. However, now there a lot of Pi4s out there now so the bar for a pro...
by timg236
Tue Aug 11, 2020 9:26 pm
Forum: General discussion
Topic: RPi-eeprom 31/07/20 has gone stable
Replies: 17
Views: 1334

Re: RPi-eeprom 31/07/20 has gone stable

Nice to see it promoted from beta yesterday. For those yet to go usb-boot (or trying to remember how to update 'cos a lot of the Youtube and other online stuff is now outdated) - I use: sudo nano /etc/default/rpi-eeprom-update to critical/stable/beta sudo apt update && sudo apt full-upgrade sudo rp...
by timg236
Tue Aug 04, 2020 11:38 am
Forum: General discussion
Topic: upgrade frozen
Replies: 2
Views: 210

Re: upgrade frozen

I think the freeze is likely either be from the vl805 helper tool doing a version check which has been removed and replaced with lspci in newer versions or a vcgencmd getting stuck. I believe the problem is in the old version of the package so once you have the new version it's ok in subsequent upda...
by timg236
Mon Aug 03, 2020 7:02 pm
Forum: General discussion
Topic: Pi4 EEPROM not recoverable / bricked
Replies: 20
Views: 995

Re: Pi4 EEPROM not recoverable / bricked

The card-detect pin is present on Pi4 and connected to GPIO31 which IIRC is shared with WLAN_ON so it isn't really used in Linux. The bootloader doesn't really use it except as a hint on the HDMI diagnostics in-case the user has forgotten to insert the card. If you have an SD-CARD breakpoint board t...
by timg236
Mon Aug 03, 2020 3:47 pm
Forum: General discussion
Topic: Pi4 EEPROM not recoverable / bricked
Replies: 20
Views: 995

Re: Pi4 EEPROM not recoverable / bricked

The very short flash of the ACT LED at power-up is not under software (or ROM) control. It's a side effect of the power initialization. It's very unlikely the EEPROM is damaged and the ROM will always attempt to read recovery.bin from the SD-CARD first. If the EEPROM rescue image created by the Rasp...
by timg236
Mon Aug 03, 2020 3:41 pm
Forum: Troubleshooting
Topic: BUG: ERROR 44 with Freshly Imaged USB Devices and Unsuccessful Initial Boot(s) using Pi 4Bs
Replies: 3
Views: 332

Re: BUG: ERROR 44 with Freshly Imaged USB Devices and Unsuccessful Initial Boot(s) using Pi 4Bs

" why would the 2020-5-27 image on the SD card boot the 8GB Pi 4B... but when that same image is installed onto the USB drive, that it wouldn't boot the 8GB Pi 4B ?? why? (rhetorical)" I can't comment on the accuracy of YouTube videos. However, the GPU firmware which supports USB MSD boot is only a...
by timg236
Mon Aug 03, 2020 10:25 am
Forum: Troubleshooting
Topic: BUG: ERROR 44 with Freshly Imaged USB Devices and Unsuccessful Initial Boot(s) using Pi 4Bs
Replies: 3
Views: 332

Re: BUG: ERROR 44 with Freshly Imaged USB Devices and Unsuccessful Initial Boot(s) using Pi 4Bs

Your description is missing the previous lines from the HDMI diagnostics screen which would give more context including the hash of the firmware being booted. However, it sounds like the start4.elf file is either missing or too old. For test purposes (and USB MSD is still under beta test until the n...
by timg236
Mon Aug 03, 2020 8:59 am
Forum: General discussion
Topic: Cpu Replacement?
Replies: 2
Views: 358

Re: Cpu Replacement?

Simple question - simple answer locked topic and removed meta-discussion
by timg236
Fri Jul 31, 2020 11:14 pm
Forum: General discussion
Topic: Actual memory bandwidth of raspberry pi4?
Replies: 75
Views: 3746

Re: Actual memory bandwidth of raspberry pi4?

The data rate of the LPDDR SDRAM is 3200.

Locking thread because it’s becoming toxic and the hardware is what it is. If you can point to a specific example which you think can br improved via a software change then please spawn a new thread.
by timg236
Fri Jul 31, 2020 10:21 pm
Forum: Troubleshooting
Topic: RPi4 not booting after latest updates
Replies: 24
Views: 784

Re: RPi4 not booting after latest updates

Linux boot and systemd is surprisingly parallel and the is the most likely thing to cause a crash due to low voltage except for benchmarks. Maybe 5.4 kernel has more optimisations. It’s also quite awkward to debug! Happy to hear that your Pi is now booting again :)

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