ibm3206k0424 ETC-unknow, ibm3206k0424 Datasheet - Page 500

• Manufacturer Part Number: ibm3206k0424
• Description: Ibm Processor For Network Resources
• Manufacturer: ETC-unknow

IBM3206K0424
IBM Processor for Network Resources
Entity 18: PowerPC On-Chip Memory (PPOCM) Entity
The PPOCM entity is comprised of several SRAM arrays that provide a xxxK memory that may be used by
the internal processor or by the IBM3206K0424. Also included in PPOCM is a DMA controller that the proces-
sor may use to do bulk data moves between the SRAM arrays and Control Memory, Packet Memory, or
memory on an external PCI device. The PPOCM arrays will subsequently referred to as on-chip memory and
the three external memories (control, packet, PCI) just mentioned will subsequently be referred to collectively
as off-chip memory.
DMA Controller
The DMA controller moves data in eight byte aligned, eight byte portions. In real addressing mode, up to 64K
bytes may be transferred at once. In virtual addressing mode, there are more restrictions. The DMA must
remain within the virtual 4K page for both the PPOCM array address and the off-chip memory address.
18.1: PPOCM Control Register
This register contains information which controls the functions of the entity. See Note on Set/Clear Type
Registers on page 93 for more details on addressing.
Length
Type
DCR Address
Power on Reset value
Restrictions
PowerPC On-Chip Memory (PPOCM) Entity
Page 500 of 676
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9
Bit(s)
31-4
3-2
1
DMA Blocking Mode
DMA Read Not Write
Reserved
Name
32 bits
Read/Write
100 AND 01
X’00000000’
None
Rserved
These bits control how non-DMA accesses to PPOCM are handled while a DMA is in
progress. They are encoded as follows:
’00’
’01’
’10’
’11’
Setting this bit will indicate the DMA being set up is to transfer data from off-chip mem-
ory into PPOCM. Clearing this bit indicates the DMA should transfer data from PPOCM
to off-chip memory.
Reserved
use an array that will be involved in the DMA.
Non-DMA PPOCM accesses are held off until the DMA is complete.
Non-DMA PPOCM accesses are held off only if the requester is attempting to
Reserved
Reserved
Description
8
7
6
5
4
pnr25.chapt05.01
August 14, 2000
3
Preliminary
2
1
0