MSC8113 Reference Manual, Rev. 0
12-10
Freescale Semiconductor
Memory Controller
12.1.7 Atomic Bus Operation
The MSC8113 device supports the following kinds of atomic bus operations BRx[ATOM]:
Read-after-write (RAWA). When a write access hits a memory bank in which
BRx[ATOM] = 01, the MSC8113 locks the bus for the exclusive use of the accessing
master (internal or external). During the lock period, no other device is granted the bus
mastership. The lock is released when the master that created the lock accesses the same
bank with a read transaction. If the master fails to release the lock within 256 bus clock
cycles, the lock is released, and a special interrupt is generated. This feature is for CAM
operations.
Write-after-read (WARA). When a read access hits a memory bank in which
BRx[ATOM] = 10, the MSC8113 locks the bus for the exclusive use of the accessing
master (internal or external). During the lock period, no other device is granted the bus
mastership. The lock is released when the master that created the lock accesses the same
bank with a write transaction. If the master fails to release the lock within 256 bus clock
cycles, the lock is released, and a special interrupt is generated.
Note:
This mechanism does not replace the 60x-compatible reservation mechanism.
12.1.8 Partial Data Valid Indication (PSDVAL)
The system bus and the local bus have an internal 64-bit data bus. According to the 60x bus
specification,
TA
is asserted when up to 64 bits (8 bytes) of data is transferred. Because the
MSC8113 device memories can have port sizes smaller than 64 bits, there is a need for a partial
data valid indication. The memory controller uses
PSDVAL
to indicate that data is latched by the
memory on write accesses or that valid data is present on read accesses. The quantity of the data
depends on the memory port size and the transfer size. The memory controller accumulates
PSDVAL
assertions, and when 64 bits (or the transfer size) are transferred, the memory controller
asserts
TA
to indicate that a 60x data beat was transferred. Table 12-1 shows the number of
PSDVAL
assertions needed for one
TA
assertion under various circumstances. Figure 12-8 shows a
64-bit transfer on 32-bit port size memory.
Table 12-1. Number of PSDVAL Assertions Needed for TA Assertion
Port Size
Transfer Size
PSDVAL Assertions
TA Assertions
64
Any
1
1
32
64 bits (8 bytes)
2
1
32
32 bits (4 bytes) 32-bit aligned
1
1
16
64 bits (8 bytes)
4
1
16
32 bits (4 bytes)
2
1
16
16/8 bits (2 bytes or 1 byte)
1
1
8
64 bits (8 bytes)
8
1
8
32 bits (4 bytes)
4
1
8
16 bits (2 bytes)
2
1
8
8 bits (1 bytes)
1
1
Summary of Contents for MSC8113
Page 1: ...MSC8113 Reference Manual Tri Core 16 Bit Digital Signal Processor MSC8113RM Rev 0 May 2008 ...
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Page 56: ...MSC8113 Reference Manual Rev 0 1 28 Freescale Semiconductor MSC8113 Overview ...
Page 76: ...MSC8113 Reference Manual Rev 0 2 20 Freescale Semiconductor SC140 Core Overview ...
Page 134: ...MSC8113 Reference Manual Rev 0 4 30 Freescale Semiconductor System Interface Unit SIU ...
Page 168: ...MSC8113 Reference Manual Rev 0 6 18 Freescale Semiconductor Boot Program ...
Page 180: ...MSC8113 Reference Manual Rev 0 7 12 Freescale Semiconductor Clocks ...
Page 260: ...MSC8113 Reference Manual Rev 0 8 80 Freescale Semiconductor Memory Map ...
Page 300: ...MSC8113 Reference Manual Rev 0 9 40 Freescale Semiconductor Extended Core ...
Page 304: ...MSC8113 Reference Manual Rev 0 10 4 Freescale Semiconductor MQBus and M2 Memory ...
Page 308: ...MSC8113 Reference Manual Rev 0 11 4 Freescale Semiconductor SQBus ...
Page 590: ...MSC8113 Reference Manual Rev 0 17 46 Freescale Semiconductor Interrupt Processing ...
Page 614: ...MSC8113 Reference Manual Rev 0 18 24 Freescale Semiconductor Debugging ...
Page 622: ...MSC8113 Reference Manual Rev 0 19 8 Freescale Semiconductor Internal Peripheral Bus IPBus ...
Page 724: ...MSC8113 Reference Manual Rev 0 21 32 Freescale Semiconductor UART ...
Page 920: ...MSC8113 Reference Manual Rev 0 25 150 Freescale Semiconductor Ethernet Controller ...
Page 1171: ...MSC8113 Reference Manual Rev 0 Freescale Semiconductor C 61 EF wait_rts P 01077FFC 9F rts 71 ...
Page 1172: ...MSC8113 Reference Manual Rev 0 C 62 Freescale Semiconductor MSC8113 Boot Code ...
Page 1202: ...MSC8113 Reference Manual Rev 0 Index 30 Freescale Semiconductor Index ...