Safe Mode

[dom]

Are you talking about putting something into the mainstream firmware release? (imho fwiw, I'd say remove the current 'pretend' hack from the firmware and just release a fix-it app.)
Anyway... Do you have "bad" samples to test against (it IS a OneTP), or are you looking for a volunteer?

Yes. It will be done from an updated start.elf.
The code for programming the board rev is already in place (and well tested). Currently you can program your board rev with:
program_board_rev=<board_rev>
in config.txt. But it only lets you if you currently have a zero board rev.

I'll change it so you can also program the board_rev if it currently differs from the reported board rev. I should push that out tonight.

[dom]

@plugh
Latest "next" tree firmware can update your board revision. Update with:

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sudo rpi-update c6b0066396723a86f390f8330a679bbce8e99b9b

(you may need to "sudo rpi-update" first).

Then add:
program_board_rev=15
to config.txt and reboot. After that, safe mode should work as expected, and:

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vcgencmd otp_dump |grep 30:

should now be 15.

The deed is done; OTP rev is now 0xF.

And vanilla 10-28 raspbian kit now boots kernel_emergency.img with GPIO3 (rev2 P1-5) pulled down.

Thanks!

The instruction to "Short Jumpers 5&6" in the wiki needs to be expanded to make sense to folks who have no clue what that means. It leaves me guessing that it means to connect the pins?

http://elinux.org/RPI_safe_mode

Also, does this apply to Arch as well, or to the Next firmware that Pepedog made available to Raspberry Pi Arch Linux users?

The instruction to "Short Jumpers 5&6" in the wiki needs to be expanded to make sense to folks who have no clue what that means. It leaves me guessing that it means to connect the pins?

http://elinux.org/RPI_safe_mode

Also, does this apply to Arch as well, or to the Next firmware that Pepedog made available to Raspberry Pi Arch Linux users?

I edited that wiki page and added a photo. I think it clarifies what to do a fair amount.

I just wanted to add that I got into trouble and needed the emergency kernel as described. I also have the incorrect OTP as described.

With a set of sharp tweezers and good eyesight, you can, with care, pull s5 pin 13 to ground by using tweezers to short it to pin 10. A third hand is useful to power on the board, but not essential if you are steady.

Strictly speaking, hitting adjacent pins cam_clk or cam_gpio is probably not a great idea if they are set up as push-pull outputs early in the boot sequence, but is unlikely to be catastrophic. But don't hold me to it. You don't have to dwell there long, as the alternate kernel should come up immediately.

Best to have your second cup of coffee after doing this maneuver. But then, you're here because you're in the soup, right? If it weren't dicey it wouldn't be fun .

...aaaand a guy should read to the end of the thread before posting. However, if you're like me and get stuck before you have updated to the latest and greatest, you still have to pull a move on S5. Or, if you're like me and tack-soldered some wires onto P1 pin 6 for an IR receiver, no jumper for you.

I will add that it's simpler just to short S5 pin 13 to the HDMI shield.

In my case, once I was in, I had to mount -t ext4 my root partition because I blew an fstab entry.

hello
I configured a daemon that starts at runlevel 2. i messed up and ended up with a hung boot process.
i got to safe mode on my raspi but im struggling when mounting the mmc so i can fix this.

i tried

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mkdir /mnt
mount /dev/mmcblk0p2 /mnt


and i get

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mount: mounting /dev/mmcblk0p2 on /mnt failed: No such file or directory


can you kindly provide any ideas on how to fix this?
thanks

hello
I configured a daemon that starts at runlevel 2. i messed up and ended up with a hung boot process.
i got to safe mode on my raspi but im struggling when mounting the mmc so i can fix this.

i tried

Code: Select all

mkdir /mnt
mount /dev/mmcblk0p2 /mnt


and i get

Code: Select all

mount: mounting /dev/mmcblk0p2 on /mnt failed: No such file or directory


can you kindly provide any ideas on how to fix this?
thanks

update: this worked for me better
http://raspberrypi.org/phpBB3//viewtopi ... 06#p163706