Altera Arria V Avalon-ST Manual do Utilizador Página 124

  • Descarregar
  • Adicionar aos meus manuais
  • Imprimir
  • Página
    / 248
  • Índice
  • MARCADORES
  • Avaliado. / 5. Com base em avaliações de clientes
Vista de página 123
Figure 7-7: MSI-X PBA Table
Pending Bits 0 through 63
Pending Bits 64 through 127
Pending Bits ((N - 1) div 64) × 64 through N - 1
QWORD 0
QWORD 1
QWORD (( N - 1) div 64)
Base
AddressPending Bit Array (PBA)
Base + 1 × 8
Base + ((N - 1) div 64) × 8
4. The IRQ Processor reads the entry in the MSI-X table.
a. If the interrupt is masked by the Vector_Control field of the MSI-X table, the interrupt remains in
the pending state.
b. If the interrupt is not masked, IRQ Processor sends Memory Write Request to the TX slave
interface. It uses the address and data from the MSI-X table. If
Message Upper Address
= 0, the
IRQ Processor creates a three-dword header. If the
Message Upper Address
> 0, it creates a 4-
dword header.
5. The host interrupt service routine detects the TLP as an interrupt and services it.
Related Information
Floor and ceiling functions
PCI Local Bus Specification, Rev. 3.0
Legacy Interrupts
Legacy interrupts are signaled on the PCIe link using message TLPs. The Arria V Hard IP for PCI Express
generates the message TLPs. The app_int_sts_vec[7:0] input vector controls interrupt generation. The
assertion of app_int_sts[<n>] causes an Assert_INTA message TLP to be generated and sent upstream.
Deassertion of app_int_sts[<n>] causes a Deassert_INTA message TLP to be generated and sent
upstream. To use legacy interrupts, you must clear the Interrupt Disable bit, which is bit 10 of the
Command register. Then, turn off the MSI Enable bit.
The following figure illustrates interrupt timing for the legacy interface. In this figure the assertion of
app_int_sts instructs the Hard IP for PCI Express to send a Assert_INTA message TLP.
Figure 7-8: Legacy Interrupt Assertion
clk
app_int_sts
The following figure illustrates the timing for deassertion of legacy interrupts. The assertion of
app_int_sts instructs the Hard IP for PCI Express to send a Deassert_INTA message.
Figure 7-9: Legacy Interrupt Deassertion
clk
app_int_sts
7-6
Legacy Interrupts
2014.12.15
Altera Corporation
Interrupts
Send Feedback
Vista de página 123
1 2 ... 119 120 121 122 123 124 125 126 127 128 129 ... 247 248

Comentários a estes Manuais

Sem comentários