DE2 Register Guide

DE2 register guide

Overview

Although DE2 is listed as a single block in the datasheet, it in fact contains several sub-blocks.

Notes

On A64 the BIT(24) at 0x01c00004 should be cleared to make DE2 to work.

Documentation

File:Allwinner DE2.0 Spec V1.0.pdf - 147 pages, 2.9MB, 18-01-2018

Sections

Most SoCs position DE2 at 0x01000000 (A64/H3/H5), but it may also be on a different address.

Section	Subsection	Offset	Description
CCU	CCU	0x00000000	DE2 Clock Controller
WB	WB	0x00010000	Write Back Controller
Transform	Transform	0x00020000	Rotate arbitrary framebuffers
Mixer	Mixer0	0x00100000	Display Mixer 0
	Mixer1	0x00200000	Display Mixer 1

CCU

Register Name	Offset	Size	Description
DE2_CCU_GATE	0x00	4 B	Module clock gate register
DE2_CCU_BUS_GATE	0x04	4 B	Bus clock gate register
DE2_CCU_RST	0x08	4 B	Bus reset register
DE2_CCU_DIV	0x0c	4 B	Module clock division register
DE2_CCU_SEL	0x10	4 B	Mixer/TCON relation register

DE2_CCU_GATE

Bit	Read/Write	Default	description
31:4	/	/	Reserved
3	Read/Write	0	Module clock gate for Transform
2	Read/Write	0	Module clock gate for WB
1	Read/Write	0	Module clock gate for Mixer 1
0	Read/Write	0	Module clock gate for Mixer 0

DE2_CCU_BUS_GATE

Bit	Read/Write	Default	description
31:4	/	/	Reserved
3	Read/Write	0	Bus gate for Transform
2	Read/Write	0	Bus gate for WB
1	Read/Write	0	Bus gate for Mixer 1
0	Read/Write	0	Bus gate for Mixer 0

DE2_CCU_RST

Bit	Read/Write	Default	description
31:4	/	/	Reserved
3	Read/Write	0	Bus reset for Transform
2	Read/Write	0	Bus reset for WB (and on A83T, H3, R40 and unknown sun8iw{9,10} SoCs, it's also the bus reset for Mixer 1)
1	Read/Write	0	Bus reset for Mixer 1 (on SoCs not mentioned above)
0	Read/Write	0	Bus reset for Mixer 0

DE2_CCU_DIV

The real division value is the value in the register part + 1.

Bit	Read/Write	Default	description
31:16	/	/	Reserved
12:15	Read/Write	0	Module clock division for Transform
8:11	Read/Write	0	Module clock division for WB
4:7	Read/Write	0	Module clock division for Mixer 1
0:3	Read/Write	0	Module clock division for Mixer 0

DE2_CCU_SEL

Bit	Read/Write	Default	description
31:1	/	/	Reserved
0	Read/Write	0	Switch Mixer and TCON relation (0 -> Mixer0 - TCON0, Mixer1 - TCON1; 1 -> Mixer0 - TCON1, Mixer1 - TCON0)

Mixer

Main mixer property is the number of supported video and UI channels. If the SoC has multiple mixers, they usually support different number of channels and first supports more channels than the second. Video channels support YUV planes and UI channels support RGB planes. Another important mixer property is maximum plane size. The exact number of supported channels of either kind and max. plane size can be found in BSP code in de_feat.[c|h] files.

vi - number of video channels
ui - number of UI channels

Subunit	Offset	Size	Count
Global Configuration	0x00000	0x01000	1
Blender	0x01000	0x01000	1
Video Channels	0x02000	0x01000	vi
UI Channels	(vi + 2) * 0x01000	0x01000	ui
Video Scaler	0x20000	0x20000	vi
UI Scaler	(vi + 1) * 0x20000	0x10000	ui
CSC	0xb0000	0x10000 (?)	1

Global Configuration

Register Name	Offset	Size	Description
GLB_CTL_REG	0x00	4 B	Global control register
GLB_STATUS_REG	0x04	4 B	Global status register
GLB_DBUFF_REG	0x08	4 B	Global double buffer register
GLB_SIZE_REG	0x0c	4 B	Global size register

GLB_CTL_REG

Note: Only mixer enable and writeback port bits are used in BSP code.

Bit	Read/Write	Default	description
31:14	/	/	Reserved
12:13	Read/Write	0	Writeback port (?)
10:11	/	/	Reserved
9	Read/Write	0	flied_rev (?)
8	Read/Write	0	sync_rev (?)
6:7	/	/	Reserved
5	Read/Write	0	Enable error IRQ
4	Read/Write	0	Enable finish IRQ
1:3	/	/	Reserved
0	Read/Write	0	Enable mixer

GLB_STATUS_REG

Note: This register is not used in BSP code.

Bit	Read/Write	Default	description
31:9	/	/	Reserved
8	Read (?)	0	Even/odd flag (?)
6:7	/	/	Reserved
5	Read (?)	0	Error status
4	Read (?)	0	Busy status
2:3	/	/	Reserved
1	Read/Write(?)	0	Error IRQ
0	Read/Write(?)	0	Finish IRQ

GLB_DBUFF_REG

Bit	Read/Write	Default	description
31:1	/	/	Reserved
0	Write (?)	0	1 -> Apply mixer settings (transfer them to DE2)

GLB_SIZE_REG

Sets mixer output size, should match width and height set in TCON and HDMI (if used).

Bit	Read/Write	Default	description
31:29	/	/	Reserved
28:16	Read/Write	0	Height - 1
15:13	/	/	Reserved
0:12	Read/Write	0	Width - 1

Blender

First enabled channel correlates to first enabled pipe and so on. To simplify things, it can be always tought as 1:1 mapping, even if channels are not used in order. Most notably, video channel is often unused, so it is ok to enable first UI channel and second pipe (when SoC have only one video channel, which is very common).

Register Name	Offset	Size	Count	Description
BLD_PIPE_CTL	0x00	4 B	1	Enable "pipes" and their fill colors
BLD_PIPE_ATTR	0x04	16 B	5	Pipe attributes
BLD_ROUTE_CTL	0x80	4 B	1	Z order of pipes
BLD_PREMULTIPLY_CTL	0x84	4 B	1	?
BLD_BKCOLOR	0x88	4 B	1	Background color
BLD_OUTPUT_SIZE	0x8c	4 B	1	Output size
BLD_MODE	0x90	4 B	4	Blending mode for each channel
BLD_CK_CTL	0xb0	4 B	1	Color key control register
BLD_CK_CFG	0xb4	4 B	1	Color key configuration
BLD_CK_MAX	0xc0	4 B	4	Max. color for color keying
BLD_CK_MIN	0xe0	4 B	4	Min. color for color keying
BLD_OUT_CTL	0xfc	4 B	4	Output control register

BLD_PIPE_CTL

Note: Enabling pipe's fill color does nothing if pipe is not enabled.

Bit	Read/Write	Default	description
31:13	/	/	Reserved
12	Read/Write	0	Enable pipe 4
11	Read/Write	0	Enable pipe 3
10	Read/Write	0	Enable pipe 2
9	Read/Write	0	Enable pipe 1
8	Read/Write	0	Enable pipe 0
7:5	/	/	Reserved
4	Read/Write	0	Enable fill color on pipe 4
3	Read/Write	0	Enable fill color on pipe 3
2	Read/Write	0	Enable fill color on pipe 2
1	Read/Write	0	Enable fill color on pipe 1
0	Read/Write	0	Enable fill color on pipe 0