Replicant

h1. PinePhone

The PinePhone is an AllWinner A64 based smartphone designed and produced by PINE64 that strives to be compatible with fully free software. It is documented in detail at "PINE64's wiki":https://wiki.pine64.org/index.php/PinePhone

h2. Components overview

|_. Feature |_. Hardware |_. Comments |_. TODO |

| System on a chip | Allwinner A64 Quad Core[9] | * The bootloader should be fully free software[7] including ARM Trusted Firmware[8].

* The code should be upstream already[7]. | TODO:

* Look at the code. |

| GPU | Mali 400 MP2 GPU[1] | * A "pipe" driver is in Linux since 5.2

* Has support in Mesa. | |

| Modem |/2. Quectel EG-25G[1] with[2] worldwide bands[4] | * The EG-25G is an international version of the EC25.

* Runs GNU/Linux[18].

* USB connection for data and I2S connection for audio[18].

* Audio connected to both PCM interfaces on the A64[14].

* PCM audio still experimental: sending to the modem works fine, receiving produces mangled samples[14]. 

* AT support commands look unusable[20], so we need to use QMI which is way more robust anyway. | TODO:

* What's the similarity with the EC-25? |

| GNSS[1]: GPS, GPS-A, GLONASS[4] | * It's part of the modem

                                    * Its NMEA protocol variant is already supported by GNU/Linux's gpsd[21]

                                    * The range is too poor to be usable due to the antenna design[22] |

| WiFi |/2. RTL8723cs[3] | * Requires a nonfree loadable firmware[3].

* Connected via SDIO[18]. | |

| Bluetooth: 4.0, A2DP[1] | * Requires a nonfree firmware[3].

* Connected via UART[18]. | TODO:

* Check if it really requires that firmware or if it has some ROM code that could be used? |

| USB – C[1] (Power, Data and Video Out) | |* USB 2.0[9]

* Serial console is only available in the headphone connector (activated by the 6th contact on the dipswitch[10])| |

| RAM | 2 or 3 GB of LPDDR3 RAM | * Initialized by u-boot SPL[18]. | |

| Main Camera | Single OmniVision OV6540, 5MP, 1/4″, LED Flash[1] | * Mainline driver[5]

* No firmware required[5]

* There's an optional non-free firmware for the auto-focus[18]. | |

| Selfie Camera | Single GC2035[1], 2MP, f/2.8, 1/5″ | | |

| Storage | Bootable microSD slot[1]

 16GB eMMC[1] | * Boot order: microSD -> eMMC[6]| |

| Sensors accelerator, gyro, proximity, compass, barometer, ambient light[1] | | | TODO:

* Which chips are used? |

| LCD panel and touchscreen | 5.95″ LCD 1440×720

18:9 aspect ratio (hardened glass) | Probably works with free software[11]. | |

| Power Management IC (PMIC) | AXP803[13] | | |

| Power Management coprocessor | AR100[15] | * The proprietary firmware can be replaced with Crust[16].

* Allows deep power-saving modes and later wake-up.

* Use case: receive signal from modem to wake-up device[17]. | |

h2. Downstream reference code

*Downstream arm-trusted-firmware*: https://gitlab.com/pine64-org/arm-trusted-firmware

*Downstream Linux*: https://gitlab.com/pine64-org/linux

*Downstream u-boot*: https://gitlab.com/pine64-org/u-boot

*Downstream utguard*: https://gitlab.com/pine64-org/mali-utgard-driver

Other projects:

* They is a fork of Linux's sunxi-next through MoeIcenowy, downstream projects such as UBports and postmarketOs gather efforts there for future upstreaming.

h2. Upstream status

h3. Linux

Current Linux upstreaming path looks like this: pine64 -> sunxi-next -> linux-next -> torvalds

Patches relevant to all A64 devices should be directly sent to sunxi-next.

Patches only relevant to PinePhone should be sent to pine64.

Status:

* "The DTS":https://gitlab.com/pine64-org/linux/-/raw/pine64-kernel-5.4.y/arch/arm64/boot/dts/allwinner/sun50i-a64-pinephone.dts needs to be cleaned up, the reference to non-upstream drivers (like the LCD panel) removed, and sent upstream. The patch adding the DTS has a signed-off-by. Sending it upstream could enable to fully upstream the u-boot port.

* The panel driver is not upstream

* The Modem PCM audio is not upstream

* The SOC (and devices?) power management is not upstream

* The "fix for the A64 timer":https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c950ca8c35eeb32224a63adc47e12f9e226da241 "is in Linux 5.1":https://linux-sunxi.org/Linux_mainlining_effort#Merged_into_5.1 and seem to be good enough to make it reliable including for userspace. The result is just a timer that is a bit less precise and slower.

h3. U-boot

The "u-boot patch that adds the pinephone":https://gitlab.com/pine64-org/u-boot/-/commit/f405aa95e7717b4772e6a9cc75e859be075dda54 consist of just a DTS and a defconfig file. 

* The dts probably needs to be upstreamed in Linux first.

* The patch has no signed-off-by but the configuration can be re-done

* The dts comes from Linux which patch has proper signed-off-by and attribution

h2. Hardware kill switches

The PinePhone has 6 hardware switches[19] that allow turning on/off different hardware components: modem, WiFi/Bluetooth, microphone, rear camera, front camera and headphones. Unfortunately these are located under the back cover, which needs to be taken out to operate them.

h2. Schematics

"PinePhone Brave Heart Schematic":http://files.pine64.org/doc/PinePhone/PinePhone_Schematic_v1.1_20191031.pdf

"PinePhone Brave Heart Changes (vs prototype units)":http://files.pine64.org/doc/PinePhone/PinePhone_BraveHeart_edition_version_1.1_change_list.pdf

"PinePhone Exploded Diagram of Brave Heart edition PinePhones":http://files.pine64.org/doc/PinePhone/PinePhone_Exploded_Diagram_ver_1.0.pdf

h2. References

fn1. Some specifications are available at the "device page":https://www.pine64.org/pinephone/ and "wiki page":https://wiki.pine64.org/index.php/PinePhone.

fn2. PinePhone discussion in Replicant's mailing list: https://lists.osuosl.org/pipermail/replicant/2019-July/001997.html

fn3. From #replicant channel on Freenode: <pre><MoeIcenowy> The Wi-Fi changed to RTL8723CS (this chip also does BT), which needs non-free firmware to be feed</pre>

fn4. From #replicant channel on Freenode: <pre><MoeIcenowy> The GNSS should be also done by EG25-G</pre>

fn5. From #replicant channel on Freenode: <pre><MoeIcenowy> The OV5640 camera doesn't need firmware and its driver is mainlined</pre>

fn6. From #replicant channel on Freenode: <pre><MoeIcenowy> The boot order is strictly MicroSD->eMMC, which is set in the A64's boot ROM</pre>

fn7. From #replicant channel on Freenode: <pre><MoeIcenowy> The bootloader (U-Boot SPL + ATF + U-Boot) is free software, all mainlined now (and the downstream dirty U-Boot cannot boot upstream Linux kernel)</pre>

need

fn8. From #replicant channel on Freenode: <pre><MoeIcenowy> https://github.com/ARM-software/arm-trusted-firmware</pre>

fn9. Allwinner A64 Datasheet: http://files.pine64.org/doc/datasheet/pine64/A64_Datasheet_V1.1.pdf

fn10. PostmarketOS Pinephone page: https://wiki.postmarketos.org/wiki/PINE64_PinePhone_(pine64-pinephone)#Serial_console

fn11. From #replicant channel on Freenode: <pre>

01:48 <adjtm> GNUtoo, lukasz confirmed me that the lcd doesn't require proprietary firmware to be uploaded

01:49 <adjtm> the conversation between pine64 staff about the lcd that someone posted on irc was probably before deciding in

               the last lcd</pre>

fn13. From Xalius on "PINE64 IRC":https://forum.pine64.org/showthread.php?tid=892. Details at: https://linux-sunxi.org/AXP803

fn14. From Xalius.

fn15. https://linux-sunxi.org/AR100

fn16. https://github.com/crust-firmware/crust

fn17. From Xalius.

fn18. PinePhone Misconceptions: https://www.pine64.org/2020/01/24/setting-the-record-straight-pinephone-misconceptions/

fn19. PinePhone at PINE64 wiki: https://wiki.pine64.org/index.php/PinePhone#Killswitch_configuration

fn20. According to Pavel Machek, "there is no RING indication on the AT side":https://pavelmachek.livejournal.com/143504.html ("archive":https://web.archive.org/web/20210913155020/https://pavelmachek.livejournal.com/143504.html) so we might be required to use QMI. QMI is probably a better long term solution anyway.

fn21. I tested it myself with gpsd + some configuration on top of a mobian image

fn22. Once a complete fix is acquired, just going under some trees in a town makes you loose the signal. Beside that a fix requires obtimal conditions, like to have good visibility of the sky. And as usual it takes a long time to acquire the first time. In general to make GPS work fine with free software we typically need the best GPS chips available as even if we manage to make AGPS work, we don't have free software supl services to make the first fix faster. The Openmoko Freerunner had working AGPS and it only used it to save and inject back the GPS data for faster fixes, but that data is only valid for a limited time period.