Programmer Interface: Control Registers¶
The Subnet Control Module implements the Debug Module Base Register Map. The reset values are listed below.
address | name | description | reset value |
---|---|---|---|
0x0000 | MOD_VENDOR |
module vendor | 0x0001 |
0x0001 | MOD_TYPE |
module type identifier | 0x0001 |
0x0002 | MOD_VERSION |
module version | 0x0000 |
0x0003 | MOD_CS |
module control and status | 0x0000 |
0x0004 | MOD_EVENT_DEST |
destination of debug events | impl.-specific |
Additionally, it implements the following control registers for module-specific functionality.
address | name | description |
---|---|---|
0x0200 | SYSTEM_VENDOR_ID |
Vendor ID |
0x0201 | SYSTEM_DEVICE_ID |
Device ID |
0x0202 | NUM_MOD |
Debug module count |
0x0203 | MAX_PKT_LEN |
Maximum packet length |
0x0204 | SYSRST |
System Reset |
System ID (SYSTEM_VENDOR_ID
)¶
- Address: 0x0200
- Reset Value: implementation specific
- Access: read-only
The vendor ID identifies the entity creating/producing the device (e.g. the chip) that contains the OSD implementation. Vendor IDs are assigned by the Open SoC Debug Project. Unassigned vendor IDs may not be used.
Note
A list of assigned vendor IDs is available online at Vendor Identifier Registry.
Device ID (SYSTEM_DEVICE_ID
)¶
- Address: 0x0201
- Reset Value: implementation specific
- Access: read-only
Number identifying the device (e.g. the chip) that contains the OSD implementation. The device ID must be uniquely describe the device design as it is visible through the debug system.
Device IDs are assigned by the device vendor, identified by SYSTEM_VENDOR_ID
.
Debug module count (NUM_MOD
)¶
- Address: 0x0202
- Reset Value: implementation specific
- Access: read-only
The number of debug modules, including the SCM module itself (which is always assigned address 0 in the subnet).
Since all module addresses must be continguous, this value also describes the highest module address available in the debug system as NUM_MOD
- 1.
Maximum packet length (MAX_PKT_LEN
)¶
- Address: 0x0203
- Reset Value: implementation specific
- Access: read-only
Maximum length of debug packets in 16 bit words, including all headers.
MAX_PKT_LEN
must be at least 12 to enable the transmission of all register access packets within one packet.
System reset (SYSRST
)¶
- Address: 0x0204
- Reset Value: implementation specific
- Access: read-only
Reset the (parts) of the system.
Bit(s) | Field | Access | Reset Value | Description |
---|---|---|---|---|
15:2 | RES |
r/w | 0x0 | Reserved |
1 | CPU_RST |
impl.-spec. | w | CPU Reset Reset all units executing code (e.g. CPUs) in the system.
|
0 | SYS_RST |
impl.-spec. | w | System Reset Put the device, excluding the debug system.
|