Registers

Old3DS Name Address Width Used by
Yes CFG11_SHAREDWRAM_32K_CODE<0-7> 0x10140000 1*8 Boot11, Process9, DSP Services
Yes CFG11_SHAREDWRAM_32K_DATA<0-7> 0x10140008 1*8 Boot11, Process9, DSP Services
Yes ? 0x10140100 2
Yes ? 0x10140102 2
Yes CFG11_FIQ_MASK 0x10140104 1 Kernel11.
Yes ? 0x10140105 1 Kernel11.
Yes Related to HID_? 0x10140108 2 TwlBg
Yes CFG_CDMA_CNT 0x1014010C 2 TwlBg
Yes CFG11_GPUPROT 0x10140140 4 Kernel11
Yes CFG11_WIFICNT 0x10140180 1 TwlBg, NWM Services
Yes CFG11_SPI_CNT 0x101401C0 2 SPI Services, TwlBg
Yes ? 0x10140200 4
No CFG11_GPU_N3DS_CNT 0x10140400 1 NewKernel11
No CFG11_CDMA_PERIPHERALS 0x10140410 4 NewKernel11
No CFG11_BOOTROM_OVERLAY_CNT 0x10140420 1 NewKernel11
No CFG11_BOOTROM_OVERLAY_VAL 0x10140424 4 NewKernel11
No ? 0x10140428 4
Yes CFG11_SOCINFO 0x10140FFC 2 Boot11, Kernel11

CFG11_SHAREDWRAM_32K_CODE

Used for mapping 32K chunks of shared WRAM for DSP data.

Bits Description
0-1 Master (0=ARM9?, 1=ARM11?, 2 or 3=DSP/code)
2-4 Offset (0..7) (slot 0..7) (LSB of address in 32Kbyte units)
5-6 Not used (0)
7 Enable (0=Disable, 1=Enable)

CFG11_SHAREDWRAM_32K_DATA

Used for mapping 32K chunks of shared WRAM for DSP data.

Bits Description
0-1 Master (0=ARM9?, 1=ARM11?, 2 or 3=DSP/data)
2-4 Offset (0..7) (slot 0..7) (LSB of address in 32Kbyte units)
5-6 Not used (0)
7 Enable (0=Disable, 1=Enable)

CFG11_FIQ_MASK

Write bit N to mask FIQ interrutps on core N? (judging from what Kernel11 does -- it only ever configures FIQ for core1)

CFG11_CDMA_CNT

Write 1 to enable, to disable.

Bits Description
0 Enable Microphone DMA (CDMA 0x00)
1 Enable NTRCARD DMA on Arm11 side (CDMA 0x01)
2-4 ?
5 WiFi. Enabled during kernel init since 11.4.

CFG11_SPI_CNT

When the corresponding bit is 0, the bus has to be accessed using the DS SPI registers. Otherwise it has to be accessed using the 3DS SPI registers.

Bit Description
0 Enable SPI Registers 0x10160800.
1 Enable SPI Registers 0x10142800.
2 Enable SPI Registers 0x10143800.

CFG11_GPU_N3DS_CNT

Bit Description
0 Enable N3DS mode? (enables access to the extra N3DS FCRAM banks, etc.)
1 Texture related? (observing texture glitches when disabling this bit)

CFG11_CDMA_PERIPHERALS

Bit Description
0-17 CDMA Peripheral 0x00-0x11 data request target (0=Old CDMA, 1=New CDMA)
18-31 Unused

CFG11_BOOTROM_OVERLAY_CNT

Bit0: Enable bootrom overlay functionality.

CFG11_BOOTROM_OVERLAY_VAL

The 32-bit value to overlay data-reads to bootrom with. See PDN_MPCORE_BOOTCNT.

CFG11_SOCINFO

Read-only register.

Bits Description Used by
0 1 on both Old3DS and New3DS. Boot11
1 1 on New3DS. Kernel11
2 N3DS SoC Mode: if set, use a 3x clock multiplier and 4 cores, otherwise 2x and 2 cores Kernel11

CFG11_GPUPROT

Old3DS Bits Description
Yes 3-0 Old FCRAM DMA cutoff size, 0 = no protection.
No 7-4 New FCRAM DMA cutoff size, 0 = no protection.
Yes 8 AXIWRAM protection, 0 = accessible.
No 10-9 QTM DMA cutoff size
Yes 31-11 Zeroes

For the old FCRAM DMA cutoff, it protects starting from 0x28000000-(0x800000*x) until end of FCRAM. There is no way to protect the first 0x800000-bytes.

For the new FCRAM DMA cutoff, it protects starting from 0x30000000-(0x800000*x) until end of FCRAM. When the old FCRAM cutoff is set to non-zero, the first 0x800000-bytes bytes of new FCRAM are protected.

On New3DS the old+new FCRAM cutoff can be used at the same time, however this isn't done officially.

For the QTM DMA cutoff, it protects starting from 0x1F400000-(0x100000*x) until end of QTM mem.

On cold boot this reg is set to 0.

When this register is set to value 0, the GPU can access the entire FCRAM, AXIWRAM, and on New3DS all QTM-mem.

Initialized during kernel boot, and used with SVC 0x59 which was implemented with v11.3.

CFG11_WIFICNT

Old3DS Bits Description
Yes 0 Enable wifi subsystem