RapidIO Interface Basics
MSC8144E Reference Manual, Rev. 3
Freescale Semiconductor
16-13
16.2.5.1 RapidIO Outbound ATMU
All outbound windows have the capability to have 2 or 4 segments, all of which are equal in size,
numbered 0–1, or 0–3, respectively. Each segment assigns attributes and the target deviceID for
an outbound transaction. All segments of a window translate to the same translation address in
the target. Additionally, each segment can be set up with 2, 4, or 8 subsegments, all of which are
equal in size. These subsegments allow a single segment to target a number of numerically
adjacent target device IDs, and, again, they all translate to the same translation address in the
targets. For example, a segment with 8 subsegments can be configured to generate a transaction
with the same set of attributes to target deviceIDs 0, 1, 2, 3, 4, 5, 6, or 7, depending on which
subsegment is addressed.
Note:
Subsegments are only supported when multiple segments are chosen.
This allows a window to be configured so that aliases can be created to the same offset within the
target device so that a single window can be used to generate different transaction types. Without
segmented windows, achieving the equivalent behavior would require multiple windows. Figure
16-2 shows an example of this capability. A window is defined to be 4 Kbyte in size, and is
defined to have 4 segments and no subsegments. Each segment is assigned to target deviceID
0x05, and each segment is given a different write transaction type attribute - segment 0 is
assigned NWRITE, segment 1 is assigned SWRITE, segment 2 is assigned NWRITE_R, and
segment 3 is assigned FLUSH. Since all of the segments are assigned to target the same device,
by writing to the same offset in each segment, a different write transaction can be generated to the
target to the same offset in the target.
So, writing to offset 0x0 in segment 0 is translated (as defined in the translation address registers)
and generates a NWRITE transaction to offset 0x0 in a 1KB window in the target with deviceID
= 0x05. A write to offset 0x0 in segment 2 is also translated, to the same offset in the target
device as the write to segment 0, but this time a NWRITE_R transaction is generated.
Figure 16-2. Single Target Example
1 Kbyte
1 Kbyte
1 Kbyte
1 Kbyte
1 Kbyte
4 Kby
te
target deviceID = 0x00000101
write ftype = NWRITE
target deviceID = 0x00000101
write ftype = FLUSH
target deviceID = 0x00000101
write ftype = SWRITE
target deviceID = 0x00000101
write ftype = NWRITE_R
4 Kbyte window with 4 segments
target deviceID = 0x00000101
Summary of Contents for MSC8144E
Page 1: ...MSC8144E Reference Manual Quad Core Media Signal Processor MSC8144ERM Rev 3 July 2009 ...
Page 48: ...MSC8144E Reference Manual Rev 3 xlviii Freescale Semiconductor ...
Page 86: ...MSC8144E Reference Manual Rev 3 1 38 Freescale Semiconductor Overview ...
Page 168: ...MSC8144E Reference Manual Rev 3 3 60 Freescale Semiconductor External Signals ...
Page 242: ...MSC8144E Reference Manual Rev 3 5 26 Freescale Semiconductor Reset ...
Page 314: ...MSC8144E Reference Manual Rev 3 8 24 Freescale Semiconductor General Configuration Registers ...
Page 414: ...MSC8144E Reference Manual Rev 3 10 14 Freescale Semiconductor MSC8144E SC3400 DSP Subsystem ...
Page 452: ...MSC8144E Reference Manual Rev 3 11 38 Freescale Semiconductor Internal Memory Subsystem ...
Page 520: ...MSC8144E Reference Manual Rev 3 12 68 Freescale Semiconductor DDR SDRAM Memory Controller ...
Page 1070: ...MSC8144E Reference Manual Rev 3 21 28 Freescale Semiconductor Timers ...