Hardware/GX2

GX2
Access
Espresso	Full
Starbuck	Full
Registers
Base	0x0c200000
Length	0x80000
Access size	32 bits
Byte order	Big Endian
IRQs
Espresso	2

The GX2 is the Wii U's main graphics processor, semantically a part of the Latte despite being used directly by the Espresso. The chip is a member of the Radeon R7xx family ^[1] (used in the Radeon HD 4330) clocked at 549.999775MHz.^[2]. While documentation perfectly matching the card is yet to be found, several documents can be brought together to form a reasonable picture of the register layout.

Reverse-engineering has revealed that the GX2's MMIO registers (referred to as GpuF0MMReg in AMD's docs) are at 0x0c200000; mapped at 0xfc200000 in Cafe OS userspace. The other MMIO locations (GpuF0Pcie, VGA_IO) are not known at this point.

• RV630 Register Reference Guide

Register guide for a similar, but not identical, card. Covers 2D graphics, CRTCs, the memory controller, etc. Does not cover 3D. Addresses for registers starting with D1 are known to match the GX2 - this reference has been successfully used to set up a framebuffer without Cafe OS running. There's evidence of another display not mentioned in this document - see the Cafe OS section below.

• Radeon R6xx/R7xx 3D Register Reference Guide

3D register guide. Applies to the whole R7xx family, so there should be no differences for the GX2.^[check] Has not been tried on hardware at time of writing.

• Radeon R6xx/R7xx Acceleration

Conceptual document explaining how to actually use the 3D engine, shader pipelines, caches, etc. Names registers, but does not give addresses (readers should cross-reference the 3D Register Reference Guide)

Not to be confused with gx2.rpl, the API for interacting with the card. Also see GX2 Registers.

References

• ¹  fail0verflow:: Console Hacking 2013: Omake - Latte
• ²  marcan tweets Wii U clock speeds