Visible to Intel only — GUID: iga1401399661140
Ixiasoft
Visible to Intel only — GUID: iga1401399661140
Ixiasoft
38.3. Register Maps
Each register has a 32-bit interface that is not byte-enabled. You must access these registers with a host that is at least 32 bits wide.
Offset | Register Name | Access | Reset Value | Description |
---|---|---|---|---|
0 – 31 | INT_CONFIG<n> | R/W | 0 | There are 32 interrupt configuration registers (INT_CONFIG0 – INT_CONFIG31). Each register contains fields to configure the behavior of its corresponding interrupt. If an interrupt input does not exist, reading the corresponding register always returns zero, and writing is ignored. Refer to the INT_CONFIG Register Map table for the INT_CONFIG register map. |
32 | INT_ENABLE | R/W | 0 | The interrupt enable register. INT_ENABLE holds the enabled status of each interrupt input. The 32 bits of the register map to the 32 interrupts available in the VIC core. For example, bit 5 corresponds to IRQ5. 45 Interrupts that are not enabled are never considered by the priority processing block, even when the interrupt input is asserted. This applies to both maskable and non-maskable interrupts. |
33 | INT_ENABLE_SET | W | 0 | The interrupt enable set register. Writing a 1 to a bit in INT_ENABLE_SET sets the corresponding bit in INT_ENABLE. Writing a 0 to a bit has no effect. Reading from this register always returns 0. 45 |
34 | INT_ENABLE_CLR | W | 0 | The interrupt enable clear register. Writing a 1 to a bit in INT_ENABLE_CLR clears corresponding bit in INT_ENABLE. Writing a 0 to a bit has no effect. Reading from this register always returns 0. 45 |
35 | INT_PENDING | R | 0 | The interrupt pending register. INT_PENDING shows the pending interrupts. Each bit corresponds to one interrupt input. If an interrupt does not exist, reading its corresponding INT_PENDING bit always returns 0, and writing is ignored. Bits in INT_PENDING are set in the following ways: An external interrupt is asserted at the VIC interface and the corresponding INT_ENABLE bit is set. An SW_INTERRUPT bit is set and the corresponding INT_ENABLE bit is set. INT_PENDING bits remain set as long as either condition applies. Refer to the Interrupt Request Block for details. 45 |
36 | INT_RAW_STATUS | R | 0 | The interrupt raw status register. INT_RAW_STATUS shows the unmasked state of the interrupt inputs. If an interrupt does not exist, reading the corresponding INT_RAW_STATUS bit always returns 0, and writing is ignored. A set bit indicates an interrupt is asserted at the interface of the VIC. The interrupt is asserted to the processor only when the corresponding bit in the interrupt enable register is set. 45 |
37 | SW_INTERRUPT | R/W | 0 | The software interrupt register. SW_INTERRUPT drives the software interrupts. Each interrupt is ORed with its external hardware interrupt and then enabled with INT_ENABLE. Refer to the Interrupt Request Block for details. 45 |
38 | SW_INTERRUPT_SET | W | 0 | The software interrupt set register. Writing a 1 to a bit in SW_INTERRUPT_SET sets the corresponding bit in SW_INTERRUPT. Writing a 0 to a bit has no effect. Reading from this register always returns 0. 45 |
39 | SW_INTERRUPT_CLR | W | 0 | The software interrupt clear register. Writing a 1 to a bit in SW_INTERRUPT_CLR clears the corresponding bit in SW_INTERRUPT. Writing a 0 to a bit has no effect. Reading from this register always returns 0. |
40 | VIC_CONFIG | R/W | 0 | The VIC configuration register. VIC_CONFIG allows software to configure settings that apply to the entire VIC. Refer to the VIC_CONFIG Register Map table for the VIC_CONFIG register map. |
41 | VIC_STATUS | R | 0 | The VIC status register. VIC_STATUS shows the current status of the VIC. Refer to the VIC_STATUS Register Map table for the VIC_STATUS register map. |
42 | VEC_TBL_BASE | R/W | 0 | The vector table base register. VEC_TBL_BASE holds the base address of the vector table in the processor’s memory space. Because the table must be aligned on a 4-byte boundary, bits 1:0 must always be 0. |
43 | VEC_TBL_ADDR | R | 0 | The vector table address register. VEC_TBL_ADDR provides the RHA for the IRQ value with the highest priority pending interrupt. If no interrupt is active, the value in this register is 0. If daisy chain input is enabled and is the highest priority interrupt, the vector table address register contains the RHA value from the daisy chain input interface. |
Bits | Field Name | Access | Reset Value | Description |
---|---|---|---|---|
0:5 | RIL | R/W | 0 | The requested interrupt level field. RIL contains the interrupt level of the interrupt requesting service. The processor can use the value in this field to determine if the interrupt is of higher priority than what the processor is currently doing. |
6 | RNMI | R/W | 0 | The requested non-maskable interrupt field. RNMI contains the non-maskable interrupt mode of the interrupt requesting service. When 0, the interrupt is maskable. When 1, the interrupt is non-maskable. |
7:12 | RRS | R/W | 0 | The requested register set field. RRS contains the number of the processor register set that the processor should use for processing the interrupt. Software must ensure that only register values supported by the processor are used. |
13:31 | Reserved |
For expanded definitions of the terms in the INT_CONFIG Register Map table, refer to the Exception Handling chapter of the Nios® II Software Developer’s Handbook.
Bits | Field Name | Access | Reset Value | Description |
---|---|---|---|---|
0:2 | VEC_SIZE | R/W | 0 | The vector size field. VEC_SIZE specifies the number of bytes in each vector table entry. VEC_SIZE is encoded as log2 (number of words) - 2. Namely: 0—4 bytes per vector table entry 1—8 bytes per vector table entry 2—16 bytes per vector table entry 3—32 bytes per vector table entry 4—64 bytes per vector table entry 5—128 bytes per vector table entry 6—256 bytes per vector table entry 7—512 bytes per vector table entry |
3 | DC | R/W | 0 | The daisy chain field. DC serves the following purposes: Enables and disables the daisy chain input interface, if present. Write a 1 to enable the daisy chain interface; write a 0 to disable it. Detects the presence of the daisy chain input interface. To detect, write a 1 to DC and then read DC. A return value of 1 means the daisy chain interface is present; 0 means the daisy chain interface is not present. |
4:31 | Reserved |
Bits | Field Name | Access | Reset Value | Description |
---|---|---|---|---|
0:5 | HI_PRI_IRQ | R | 0 | The highest priority interrupt field. HI_PRI_IRQ contains the IRQ number of the active interrupt with the highest RIL. When there is no active interrupt (IP is 0), reading from this field returns 0. When the daisy chain input is enabled and it is the highest priority interrupt, then the value read from this field is 32. Bit 5 always reads back 0 when the daisy chain input is not present. |
6:30 | Reserved | |||
31 | IP | R | 0 | The interrupt pending field. IP indicates when there is an interrupt ready to be serviced. A 1 indicates an interrupt is pending; a 0 indicates no interrupt is pending. |