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raspberrypi / firmware

This repository contains pre-compiled binaries of the current Raspberry Pi kernel and modules, userspace libraries, and bootloader/GPU firmware.
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Default core voltage on Pi zero is 1.80V with recent firmware #1667

Open IanSB opened 2 years ago

IanSB commented 2 years ago

I'm working on this bare metal project for the Pi zero: https://github.com/IanSB/RGBtoHDMI/wiki

I recently started using newer firmware (bootcode.bin, fixup_cd.dat, start_cd.elf) but the default core voltage has increased from 1.35V to 1.80V on the Pi zero or zeroW on all firmware from the 14-jul-2021 commit. The most recent one that works for me is the commit on 21-apr-2021

Other pi models (pi1, 2 ,3 zero2) have sensible voltages between 1.20 and 1.35 volts with recent firmware

My software doesn't attempt to change the voltage either via the mailbox or using config.txt

21-apr-2021 commit: capture14

14-jul-2021 commit and all later versions: capture15

pelwell commented 2 years ago

A voltage scaling bug that only affected Pi Zeros was introduced in May 2021 and fixed on 14th November. Although it reports a voltage of 1.8V, the hardware actually caps this to just under 1.4V - not ideal, but not catastrophic.

Firmwares built since 14th November, include the current stable and oldstable branches includes this patch.

IanSB commented 2 years ago

Firmwares built since 14th November, include the current stable and oldstable branches includes this patch.

Thanks, I'd been using the files from the most recent raspberry Pi OS image I had which were dated 29/10/21 and I'd been getting some reports of lockups with my latest beta releases which is why I started looking at it. I thought I'd also tested the most recent firmware build but I guess not.

the hardware actually caps this to just under 1.4V - not ideal, but not catastrophic.

I noticed that vcgencmd returned 1.4V

hoglet67 commented 2 years ago

@pelwell Is there a Github issue for the voltage scaling bug?

pelwell commented 2 years ago

I think you are reading it.

IanSB commented 2 years ago

@pelwell

the hardware actually caps this to just under 1.4V - not ideal, but not catastrophic.

Has this set the over voltage warranty bit? (The project uses force_turbo=1 but doesn't use overvoltage settings)

popcornmix commented 2 years ago

Has this set the over voltage warranty bit? (The project uses force_turbo=1 but doesn't use overvoltage settings)

No, you need an explicit over_voltage settings (plus force_turbo=1) to set the warranty bit.