HIPC

Marshall Portion

This is an array of u32's.

Word	Bits	Description
0	15-0	IPC version? Always 4.
0	19-16	Number of marshalls type X (each: 2 words). Type mask: 8
0	23-20	Number of buf descriptors (each: 3 words). Type mask: 5
0	27-24	Number of buf2 descriptors (each: 3 words). Type mask: 6
0	31-28	Number of marshalls type W (each: 3 words)
1	9-0	Size of data portion in u32's.
1	13-10	Marshal type T something.
1	17-14	Marshal type T something.
1	31	Enable special descriptor.
...		Special descriptor, if enabled.
...		Type X descriptors, each one 2 words.
...		Buf descriptors, each one 3 words.
...		Buf2 descriptors, each one 3 words.
...		Type W descriptors, each one 3 words.

Special descriptor

There can only be one of this descriptor type. It is enabled by bit31 of the second word.

Word	Bits	Description
0	0	?
0	4-1	Number of A-words for this special descriptor (=x).
0	8-5	Number of B-words for this special descriptor (=y).
1		A-words, purpose unknown.
1+x		B-words, purpose unknown.

Buf descriptor

They fucked up this one, big time.

Word	Bits	Description
0		Lower 32-bits of size.
1		Lower 32-bits of address.
2	0	Always set to 1 or 3. R/RW.
2	4-2	Bit 38-36 of address.
2	27-24	Bit 35-32 of size.
2	31-28	Bit 35-32 of address.

Descriptor type B

Word	Description
0	Lower 32-bits of addr?
1	Upper 16bits: Size, Lower 16bits: Rest of addr?

Descriptor type C

Word	Description
0	Upper 16bits: Size, Lower 16: ?
1	?

Data Portion

This is an array of u64's placed after the marshall header. But it's always aligned to 16 so sometimes there is padding words inserted inbetween.

Word	Description
0	Magic ("SFCI")
1	Cmd id
...	Non-marshalled data is placed here

Cmd header

Cmd header 1	Cmd header 2	Description
4	9	Data portion size 20.
4	10	Data portion size 24.
4	12	Data portion size 32.
4	14	Data portion size 40.
4	0x8000000C	Marshall words: (u32) 1. Data portion size 32.