A number of memory-mapped registers are available to control Ibex-related functionality that's specific to OpenTitan.
Alert Test Register
- Offset:
0x0
- Reset default:
0x0
- Reset mask:
0xf
{"reg": [{"name": "fatal_sw_err", "bits": 1, "attr": ["wo"], "rotate": -90}, {"name": "recov_sw_err", "bits": 1, "attr": ["wo"], "rotate": -90}, {"name": "fatal_hw_err", "bits": 1, "attr": ["wo"], "rotate": -90}, {"name": "recov_hw_err", "bits": 1, "attr": ["wo"], "rotate": -90}, {"bits": 28}], "config": {"lanes": 1, "fontsize": 10, "vspace": 140}}
Bits |
Type |
Reset |
Name |
Description |
31:4 |
|
|
|
Reserved |
3 |
wo |
0x0 |
recov_hw_err |
Write 1 to trigger one alert event of this kind. |
2 |
wo |
0x0 |
fatal_hw_err |
Write 1 to trigger one alert event of this kind. |
1 |
wo |
0x0 |
recov_sw_err |
Write 1 to trigger one alert event of this kind. |
0 |
wo |
0x0 |
fatal_sw_err |
Write 1 to trigger one alert event of this kind. |
Software recoverable error
- Offset:
0x4
- Reset default:
0x9
- Reset mask:
0xf
{"reg": [{"name": "VAL", "bits": 4, "attr": ["rw"], "rotate": 0}, {"bits": 28}], "config": {"lanes": 1, "fontsize": 10, "vspace": 80}}
Bits |
Type |
Reset |
Name |
Description |
31:4 |
|
|
|
Reserved |
3:0 |
rw |
0x9 |
VAL |
Software recoverable alert. When set to any value other than kMultiBitBool4False, a recoverable alert is sent. Once the alert is sent, the field is then reset to kMultiBitBool4False. |
Software fatal error
- Offset:
0x8
- Reset default:
0x9
- Reset mask:
0xf
{"reg": [{"name": "VAL", "bits": 4, "attr": ["rw1s"], "rotate": 0}, {"bits": 28}], "config": {"lanes": 1, "fontsize": 10, "vspace": 80}}
Bits |
Type |
Reset |
Name |
Description |
31:4 |
|
|
|
Reserved |
3:0 |
rw1s |
0x9 |
VAL |
Software fatal alert. When set to any value other than kMultiBitBool4False, a fatal alert is sent. Note, this field once cleared cannot be set and will continuously cause alert events. |
Ibus address control regwen.
- Reset default:
0x1
- Reset mask:
0x1
Name |
Offset |
IBUS_REGWEN_0 |
0xc |
IBUS_REGWEN_1 |
0x10 |
{"reg": [{"name": "EN", "bits": 1, "attr": ["rw0c"], "rotate": -90}, {"bits": 31}], "config": {"lanes": 1, "fontsize": 10, "vspace": 80}}
Bits |
Type |
Reset |
Name |
31:1 |
|
|
Reserved |
0 |
rw0c |
0x1 |
EN |
Ibus address controls write enable. Once set to 0, it can longer be configured to 1
Value |
Name |
Description |
0x0 |
locked |
Address controls can no longer be configured until next reset. |
0x1 |
enabled |
Address controls can still be configured. |
Enable Ibus address matching
- Reset default:
0x0
- Reset mask:
0x1
Name |
Offset |
IBUS_ADDR_EN_0 |
0x14 |
IBUS_ADDR_EN_1 |
0x18 |
{"reg": [{"name": "EN", "bits": 1, "attr": ["rw"], "rotate": -90}, {"bits": 31}], "config": {"lanes": 1, "fontsize": 10, "vspace": 80}}
Bits |
Type |
Reset |
Name |
Description |
31:1 |
|
|
|
Reserved |
0 |
rw |
0x0 |
EN |
Enable ibus address matching. |
Matching region programming for ibus.
The value programmed is done at power-of-2 alignment.
For example, if the intended matching region is 0x8000_0000 to 0x8000_FFFF, the value programmed is 0x8000_7FFF.
The value programmed can be determined from the translation granule.
Assume the user wishes to translate a specific 64KB block to a different address:
64KB has a hex value of 0x10000.
Subtract 1 from this value and then right shift by one to obtain 0x7FFF.
This value is then logically OR'd with the upper address bits that would select which 64KB to translate.
In this example, the user wishes to translate the 0x8000-th 64KB block.
The value programmed is then 0x8000_7FFF.
If the user were to translate the 0x8001-th 64KB block, the value programmed would be 0x8001_7FFF.
- Reset default:
0x0
- Reset mask:
0xffffffff
Name |
Offset |
IBUS_ADDR_MATCHING_0 |
0x1c |
IBUS_ADDR_MATCHING_1 |
0x20 |
{"reg": [{"name": "VAL", "bits": 32, "attr": ["rw"], "rotate": 0}], "config": {"lanes": 1, "fontsize": 10, "vspace": 80}}
Bits |
Type |
Reset |
Name |
Description |
31:0 |
rw |
0x0 |
VAL |
Matching region value |
The remap address after a match has been made.
The remap bits apply only to top portion of address bits not covered by the matching region.
For example, if the translation region is 64KB, the remapped address applies only to the upper
address bits that select which 64KB to be translated.
- Reset default:
0x0
- Reset mask:
0xffffffff
Name |
Offset |
IBUS_REMAP_ADDR_0 |
0x24 |
IBUS_REMAP_ADDR_1 |
0x28 |
{"reg": [{"name": "VAL", "bits": 32, "attr": ["rw"], "rotate": 0}], "config": {"lanes": 1, "fontsize": 10, "vspace": 80}}
Bits |
Type |
Reset |
Name |
Description |
31:0 |
rw |
0x0 |
VAL |
Remap addr value |
Dbus address control regwen.
- Reset default:
0x1
- Reset mask:
0x1
Name |
Offset |
DBUS_REGWEN_0 |
0x2c |
DBUS_REGWEN_1 |
0x30 |
{"reg": [{"name": "EN", "bits": 1, "attr": ["rw0c"], "rotate": -90}, {"bits": 31}], "config": {"lanes": 1, "fontsize": 10, "vspace": 80}}
Bits |
Type |
Reset |
Name |
31:1 |
|
|
Reserved |
0 |
rw0c |
0x1 |
EN |
Ibus address controls write enable. Once set to 0, it can longer be configured to 1
Value |
Name |
Description |
0x0 |
locked |
Address controls can no longer be configured until next reset. |
0x1 |
enabled |
Address controls can still be configured. |
Enable dbus address matching
- Reset default:
0x0
- Reset mask:
0x1
Name |
Offset |
DBUS_ADDR_EN_0 |
0x34 |
DBUS_ADDR_EN_1 |
0x38 |
{"reg": [{"name": "EN", "bits": 1, "attr": ["rw"], "rotate": -90}, {"bits": 31}], "config": {"lanes": 1, "fontsize": 10, "vspace": 80}}
Bits |
Type |
Reset |
Name |
Description |
31:1 |
|
|
|
Reserved |
0 |
rw |
0x0 |
EN |
Enable dbus address matching. |
See IBUS_ADDR_MATCHING_0
for detailed description.
- Reset default:
0x0
- Reset mask:
0xffffffff
Name |
Offset |
DBUS_ADDR_MATCHING_0 |
0x3c |
DBUS_ADDR_MATCHING_1 |
0x40 |
{"reg": [{"name": "VAL", "bits": 32, "attr": ["rw"], "rotate": 0}], "config": {"lanes": 1, "fontsize": 10, "vspace": 80}}
Bits |
Type |
Reset |
Name |
Description |
31:0 |
rw |
0x0 |
VAL |
Matching region value |
See IBUS_REMAP_ADDR_0
for a detailed description.
- Reset default:
0x0
- Reset mask:
0xffffffff
Name |
Offset |
DBUS_REMAP_ADDR_0 |
0x44 |
DBUS_REMAP_ADDR_1 |
0x48 |
{"reg": [{"name": "VAL", "bits": 32, "attr": ["rw"], "rotate": 0}], "config": {"lanes": 1, "fontsize": 10, "vspace": 80}}
Bits |
Type |
Reset |
Name |
Description |
31:0 |
rw |
0x0 |
VAL |
Remap addr value |
Enable mask for NMI.
Once an enable mask is set, it cannot be disabled.
- Offset:
0x4c
- Reset default:
0x0
- Reset mask:
0x3
{"reg": [{"name": "ALERT_EN", "bits": 1, "attr": ["rw1s"], "rotate": -90}, {"name": "WDOG_EN", "bits": 1, "attr": ["rw1s"], "rotate": -90}, {"bits": 30}], "config": {"lanes": 1, "fontsize": 10, "vspace": 100}}
Bits |
Type |
Reset |
Name |
Description |
31:2 |
|
|
|
Reserved |
1 |
rw1s |
0x0 |
WDOG_EN |
Enable mask for watchdog NMI |
0 |
rw1s |
0x0 |
ALERT_EN |
Enable mask for alert NMI |
Current NMI state
- Offset:
0x50
- Reset default:
0x0
- Reset mask:
0x3
{"reg": [{"name": "ALERT", "bits": 1, "attr": ["rw1c"], "rotate": -90}, {"name": "WDOG", "bits": 1, "attr": ["rw1c"], "rotate": -90}, {"bits": 30}], "config": {"lanes": 1, "fontsize": 10, "vspace": 80}}
Bits |
Type |
Reset |
Name |
Description |
31:2 |
|
|
|
Reserved |
1 |
rw1c |
0x0 |
WDOG |
Current state for watchdog NMI |
0 |
rw1c |
0x0 |
ALERT |
Current state for alert NMI |
error status
- Offset:
0x54
- Reset default:
0x0
- Reset mask:
0x701
{"reg": [{"name": "REG_INTG_ERR", "bits": 1, "attr": ["rw1c"], "rotate": -90}, {"bits": 7}, {"name": "FATAL_INTG_ERR", "bits": 1, "attr": ["rw1c"], "rotate": -90}, {"name": "FATAL_CORE_ERR", "bits": 1, "attr": ["rw1c"], "rotate": -90}, {"name": "RECOV_CORE_ERR", "bits": 1, "attr": ["rw1c"], "rotate": -90}, {"bits": 21}], "config": {"lanes": 1, "fontsize": 10, "vspace": 160}}
Bits |
Type |
Reset |
Name |
Description |
31:11 |
|
|
|
Reserved |
10 |
rw1c |
0x0 |
RECOV_CORE_ERR |
rv_core_ibex detected a recoverable internal error (alert_minor from Ibex seen) |
9 |
rw1c |
0x0 |
FATAL_CORE_ERR |
rv_core_ibex detected a fatal internal error (alert_major_internal_o from Ibex seen) |
8 |
rw1c |
0x0 |
FATAL_INTG_ERR |
rv_core_ibex detected a response integrity error |
7:1 |
|
|
|
Reserved |
0 |
rw1c |
0x0 |
REG_INTG_ERR |
rv_core_ibex_peri detected a register transmission integrity error |
Random data from EDN
- Offset:
0x58
- Reset default:
0x0
- Reset mask:
0xffffffff
{"reg": [{"name": "DATA", "bits": 32, "attr": ["ro"], "rotate": 0}], "config": {"lanes": 1, "fontsize": 10, "vspace": 80}}
Bits |
Type |
Reset |
Name |
31:0 |
ro |
0x0 |
DATA |
Random bits taken from the EDN. RND_STATUS.RND_DATA_VALID
indicates if this data is valid. When valid, reading from this
register invalidates the data and requests new data from the EDN.
The register becomes valid again when the EDN provides new data.
When invalid the register value will read as 0x0 with an EDN
request for new data pending. Upon reset the data will be invalid
with a new EDN request pending.
Status of random data in RND_DATA
- Offset:
0x5c
- Reset default:
0x0
- Reset mask:
0x3
{"reg": [{"name": "RND_DATA_VALID", "bits": 1, "attr": ["ro"], "rotate": -90}, {"name": "RND_DATA_FIPS", "bits": 1, "attr": ["ro"], "rotate": -90}, {"bits": 30}], "config": {"lanes": 1, "fontsize": 10, "vspace": 160}}
FPGA build timestamp info.
This register only contains valid data for fpga, for all other variants it is simply 0.
- Offset:
0x60
- Reset default:
0x0
- Reset mask:
0xffffffff
{"reg": [{"name": "VAL", "bits": 32, "attr": ["ro"], "rotate": 0}], "config": {"lanes": 1, "fontsize": 10, "vspace": 80}}
Bits |
Type |
Reset |
Name |
Description |
31:0 |
ro |
0x0 |
VAL |
FPGA build timestamp information. |
Exposed tlul window for DV only purposes.
- Word Aligned Offset Range:
0x80
to0x9c
- Size (words):
8
- Access:
rw
- Byte writes are supported.