Recent answers to How much proprietary software, if any, is contained in Firefox OS phones?https://support.mozilla.org/en-US/questions/9763762013-11-04T07:34:11-08:00Everything from Gecko up to Gaia is open source.
The lower level layers underneath are mostly open, 2013-11-04T07:34:11-08:00hub_https://support.mozilla.org/en-US/questions/976376#answer-497501<p>Everything from Gecko up to Gaia is open source.
</p><p>The lower level layers underneath are mostly open, as the kernel, bionic and several other components from Android are released under an open source license.
</p><p>Notable exceptions are GPU drivers (the vendor most of the time doesn't release the source code) that live in user land, some hardware binary drivers and in general the radio chipsets (wifi, cellular). This depends on the device, the vendors policy, etc.
Also the RIL might be closed. We have an open source one, but the vendor might chose to not use it.
</p><p>None of this is under the control of Mozilla.
</p>What bits are proprietary is typically upto the phone manufacturer/carrier.
Sometimes some portions 2013-11-04T07:06:05-08:00dhylandshttps://support.mozilla.org/en-US/questions/976376#answer-497494<p>What bits are proprietary is typically upto the phone manufacturer/carrier.
</p><p>Sometimes some portions of the bootloader is open, sometimes it is closed. Sometimes the bootloader is locked (i.e. requires a signed bootloader) and sometimes it isn't. It may also depend on which bootloader is being referred to (as there are typically several stages of bootloading).
</p><p>I'm not aware of any phone manufacturer which makes the modem firmware source code available.
</p><p>Mozilla delivers source code to the phone manufacturer and/or carrier for the gecko/gaia bits and they build the rest of the system. So the exact makeup of what goes into the phone is upto the phone manufacturer/carrier.
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