PECI

The WPCM450 has a PECI controller, that allows it to interface with Intel chipsets directly, in order to read sensor values.

device	MMIO	IRQ	description
PECI	0xb8000200	6	PECI controller

Registers

The register interface is very similar to the one in NPCM7xx SoCs.

offset	type	name	description
0x00	u8	CTL_STS	control and status register
0x04	u8	RD_LENGTH	number of bytes to read
0x08	u8	ADDR	PECI client (target) address
0x0C	u8	CMD	PECI command code
0x1C	u8	WR_LENGTH	number of bytes to write
0x40	u8	DAT_INOUT0	input/output buffer, byte 0
0x44	u8	DAT_INOUT1	input/output buffer, byte 1
...	...	...
0x7C	u8	DAT_INOUTF	input/output buffer, byte 15

References

• Dell driver (header)
• OpenBMC driver for NPCM7xx