XO4 Bringup

This page lists goals and plans for initial bringup of the XO 4 A1 motherboard, the first prototype of the XO-4 Laptop.

Status

Note that a check in any one of the two columns is generally sufficient to prove that the hardware works.

Bringup status

Subsystem	OFW	Linux	Notes/Reference
CPU Boot	X	X
Serial port	X	X
Host/EC communications	X		XO_1.75_HOST_to_EC_Protocol
Host/EC programming	X
PS/2 KB & Touchpad	X
USB	X
SD (Int/Ext)	X	X
eMMC	X	X
DCON/Display	X
Audio playback (Int/Ext)	X
Audio recording (Int/Ext)
SDIO WLAN	X	X
Battery charging	X
Touchscreen
OFW SPI Flash Prog.	X
Camera	X

Goals

The goal of a A-phase board bring-up is get a small number of boards to an acceptable state of functionality. At this point, a larger number of boards are modified to match and distributed for both extended testing of basic functionality (esp. memory stability) and development of software to access further functionality.

The following are the goals of this bringup:

• EC code booting and controlling the power sequencing properly
• CPU booting OFW
• Reliable memory and internal SD operation from OFW
• Reliable use of USB ports from OFW
• Support for the display and keyboard from OFW and Linux
• Support for reprogramming the EC SPI Flash from CPU

Non-goals

We can go home even if these aren't working

• Proper operation of audio interface
• Proper operation of the wireless LAN
• Camera
• Linux

Personnel

• Wad (EE), Gary Chiang (EE), Richard (EC/OFW), Mitch (OFW), Paul (EC/Linux), from OLPC
• Mars (PM), Eddie (PM), Beckham Chen (EE), from Quanta R&D