[Samsung Galaxy S 5 Unified Development] curiousrom:
S5 Odin Flashable Modem & Bootloader

For which Galaxy S5 model exactly as they have different specific modems & bootloaders. For example the LineageOS 16.0 klte is a unified firmware that supports all these different models: SM-G900AZ, SM-G900F, SM-G900M, SM-G900R4, SM-G900R7, SM-G900T, SM-G900V, SM-G900W8, SM-S902L.

You can check in haggertk's (maintainer of LineageOS S5 klte + variants & one of the 9 LineageOS Project directors) Bootloader_Modem_Firmware lineage-17.1 - lineage-18.1 download folders. These are flashable bootloader/modem combos & can be flashed on the Galaxy S5 regardless of the OS you are running @ the present (Samsung stock or custom ROM) using the Odin method on a Windows PC as described below or the little bit more complicated Heimdall method on Linux or Mac OS.

Special case: SM-G900V This package contains only G900V DQL1 modem.bin (2g & 3G), NON_HLOS.bin (LTE modem), rpm.mbn, sbl1.mbn, sdi.mbn & tz.mbn only. It does not include aboot (the S5's bootloader) so not to lock the bootloader if it was unlocked. How to check G900V bootloader status & how-to unlock link if necessary here.

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XDA posts, Odin flashable:

S5 SM-G900I Modem CQK1 & Bootloader CQJ2 (The most recent for the G900I region Australia @ the present). Or flash the most recent stock Samsung firmware for your S5 SM-G900I from here or here to get the 2019-04-04 G900IDDS1CQA1 modem for India.

The higher the last 4 alphanumeric characters, the more recent it is.

SM-S902L - Sadly it's a MVNO branded S5 & they did not bother making any Samsung OS updates for it. The only modems available for that model are the old KitKat 4.4.2 era S902LUDUAOD3 & S902LUDU3AOG2 that will not support the fingerprint sensor in LineageOS 16.0. A search for firmware for SM-S902L on sammobile and on updato returns only Samsung 4.4.2.

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Using Samsung Firmware to Update Modem & Bootloader

Or you can do it the hard way & flash the most recent stock Samsung firmware for your S5 with Odin3 & it will update your bootloader (named aboot in the S5) & modem. Afterwards you need to flash TWRP via Odin3, make the important EFS partition backup in TWRP while running the Samsung firmware and either restore a System + Data + Boot (kernel) LineageOS TWRP backup or do a S5 LineageOS Super Clean Install.

If you currently have a working custom ROM setup like LineageOS and want to update your modem & aboot bootloader using the stock Samsung firmware you can backup your current setup & restore it afterwards:

Do a full backup in TWRP (except the caches) to the external Micro SD card which BTW does not include the internal sdcard. (screenshot)

Backup the internal sdcard to computer.

Flash Samsung stock using Odin3.

Test mobile data, screenshot or write down working APN settings.

Flash TWRP using Odin3. (See Flashing TWRP on Stock Samsung Firmware in the Super Clean post.)

Backup the EFS partition only to external Micro SD card.

Restore TWRP backup made in step 1 but ONLY the System, Data & Boot (kernel) partitions & nothing else! That means not the modem, EFS & caches. (screenshot)

WARNING: If you flash stock Samsung OS on the special case S5 SM-G900V it will re-lock the bootloader and you will have to unlock it again as described in [GUIDE] Root, Bootloader Unlocks, and More!.

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How I Updated Bootloader & Modem of My S5 on a Windows PC

Got the most recent Odin (@ the present) Odin3 v3.14.1 https://dl2018.sammobile.com/Odin3-v3.14.1.zip. Extract it to a Odin3-v3.14.1 folder which I like to put in the root of my C drive to keep the paths simple..

Downloaded the .tar file for my S5 SM-G900M his G900MUBS1CQD5_G900MUBS1CQA3_Baseband_Firmware.tar.md5. Copied it to the Odin3-v3.14.1 folder. Note: some files have the integrated .md5 hash function, some don't.

With the S5 off, turned on the S5 directly in Download mode (press and hold Home + Power + Volume Down buttons and confirm with Volume up to Continue).

Connected to the computer running Odin3, used the AP button to add the file, kept the default Options Auto Reboot & F. Reset Time selected & nothing else then clicked Start.

Disconnected the S5 while it was rebooting. Done!

As you can see in the Log window of the Odin3 screenshot, all the files that haggertk listed in his post are included in his packages & were successfully flashed.

The second screenshot is of DevCheck > System where you can see Bootloader & Radio which is the same as modem or baseband.

You can also see your current bootloader & modem using adb:

adb shell getprop > getprop_Properties.txt

And search the file with bootloader & modem. Or to see it on your screen:

adb shell getprop gsm.version.baseband

adb shell getprop ro.bootloader

Linux users: @fitittome made a post about using Heimdall on Linux here: Heimdall Baseband Install but Odin3 is much easier to use IMO.

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