ADSP-BF535 Blackfin Processor Hardware Reference
13-11
PCI Bus Interface
both masks and both BAPs, it should allow PCI configuration software
running on the host processor to configure the PCI interface from the PCI
bus. This is done by setting the PCI Enable bit in the
PCI_CTL
register.
Any configuration accesses to the PCI module before this bit is set are
retried by the PCI module. It is a stipulation of the PCI protocol that this
bit must be set. That is, the device has up to 2
25
PCI cycles to initialize
itself after
PCI_RST#
is asserted.
When PCI configuration software has configured the PCI interface, it is
configured with a memory and/or I/O address range for which it claims
the current transaction as the target.
There is no incoming transaction FIFO, so only one transaction can occur
at a time. Each of the data FIFOs is 8
32-bit words deep. If a burst
greater than 8 words comes in, then each time the FIFO fills up, the PCI
bus is retried until space is available for the next word.
Two status bits in the
PCI_STAT
register are set whenever the Slave TX
Data FIFO or Slave RX Data FIFO have data written into them. These
bits are sticky and can be configured by the
PCI_ICTL
register to generate
interrupts. They can be used to determine PCI target bandwidth effi-
ciency or for general debugging of PCI target operation.
The PCI interface can also perform fast back-to-back accesses, which
make multiple word accesses (not bursts) more efficient by removing the
usually mandatory single idle cycle between transfers. The PCI interface
can only perform fast back-to-back transfers when configuration software
sets the Fast Back-to-Back Enable bit in the command register of the core
PCI configuration space. This bit is set when all of the slaves on the PCI
bus are fast back-to-back capable. The ADSP-BF535 processor must also
enable its own ability to do fast back-to-back transfers by setting the Fast
Back-to-Back Enable bit in the
PCI_CTL
register. This bit may be set and
cleared at any time during operation to enable and disable fast
back-to-back transfers whenever necessary.
Summary of Contents for ADSP-BF535 Blackfin
Page 80: ...Development Tools 1 26 ADSP BF535 Blackfin Processor Hardware Reference...
Page 312: ...Working With Memory 6 86 ADSP BF535 Blackfin Processor Hardware Reference...
Page 332: ...System Interfaces 7 20 ADSP BF535 Blackfin Processor Hardware Reference...
Page 360: ...Dynamic Power Management Controller 8 28 ADSP BF535 Blackfin Processor Hardware Reference...
Page 446: ...Beginning and Ending an SPI Transfer 10 40 ADSP BF535 Blackfin Processor Hardware Reference...
Page 522: ...Timing Examples 11 76 ADSP BF535 Blackfin Processor Hardware Reference...
Page 562: ...IrDA Support 12 40 ADSP BF535 Blackfin Processor Hardware Reference...
Page 608: ...PCI I O Issues 13 46 ADSP BF535 Blackfin Processor Hardware Reference...
Page 672: ...References 14 64 ADSP BF535 Blackfin Processor Hardware Reference...
Page 810: ...SDRAM Controller SDC 18 86 ADSP BF535 Blackfin Processor Hardware Reference...
Page 811: ...ADSP BF535 Blackfin Processor Hardware Reference 18 87 External Bus Interface Unit...
Page 812: ...SDRAM Controller SDC 18 88 ADSP BF535 Blackfin Processor Hardware Reference...
Page 860: ...DMA Bus Debug Registers 20 30 ADSP BF535 Blackfin Processor Hardware Reference...