Mediatek Jargon

Mediatek Jargon

SoC Components

SLBC

• Only on MT8196?
• System Level Buffer and Cache. Part of the EMI. DRAM cache that appears to be for I/O. Improves system performance and is not required.
• https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/6074016

EMI

• External memory interconnect?
• Also referred to as the interconnect (ICC) or DRAM scheduler or DRAM controller.

DVFSRC

• Dynamic Voltage and Frequency Scaling Resource Controller. Collects requests from software and hardware to decide on minimum operating voltage and DRAM frequency. Talks to the EMI to set DRAM stuff and talks to regulators to set voltage.
• https://lore.kernel.org/all/20240610085735.147134-1-angelogioacchino.delregno@collabora.com/

MMSYS

• Multimedia subsystem
• Includes display, camera, video encode/decode, image processing, vpu.

Display Hardware

• OVL: Overlay(?), source of image data.
• DSI: In Chromebooks, the output that goes to the internal display.
• DPI: In Chromebooks, the output that goes to the external display.

SCPSYS

• System Control Processor subsystem.
• spm (system power manager)

PMIC WRAP

• Wrapper hardware to interface to PMICs.

SPMI

• Standard interface for power management.
• MTK has its own version of this (PMIF).

CMDQ

• Mediatek Command Queue.
• Used for time sensitive register access (such as configuring display hardware).

GCE

• Global Command Engine
• The mailbox used by cmdq to configure the display pipeline.

SCP

• System Companion Processor
• Offloads certain tasks TODO: add what scp controls here

SMI

• Smart Multimedia Interface
• Enables/disables iommus
• Controls power domains and clocks
• Used only for display hardware? (i think only the display controller is behind an iommu, at least on older SoCs)

LARBs

• Local arbiters