Hardware Reference Manual 119
Intel® IXP2800 Network Processor
Intel XScale® Core

3.9.4.9 Coprocessor Instructions

3.9.4.10 Miscellaneous Instruction Timing

3.9.4.11 Thumb Instructions

The timing of Thumb instructions are the same as their equivalent ARM* instructions. This
mapping can be found in the ARM* Architecture Reference Manual. The only exception is the
Thumb BL instruction when H = 0; the timing in this case would be the same as an ARM* data
processing instruction.
3.10 Test Features
This section gives a brief overview of the Intel XScale® core JTAG features. The Intel XScale®
core provides test features compatible with the IEEE Standard Test Access Port and Boundary Scan
Architecture (IEEE Std. 1149.1). These features include a TAP controller, a 5-bit instruction
register, and test data registers to support software debug. The Intel XScale® core also provides
support for a boundary-scan register, device ID register, and other data test registers.
A full description of these features can be found in the Intel® IXP2400 and IXP2800 Network
Processor Programmer’s Reference Manual.
Table 39. CP15 Register Access Instruction Timings
Mnemonic Minimum Issue Latency Minimum Result Latency
MRC 4 4
MCR 2 N/A
Table 40. CP14 Register Access Instruction Timings
Mnemonic Minimum Issue Latency Minimum Result Latency
MRC 7 7
MCR 7 N/A
LDC 10 N/A
STC 7 N/A
Table 41. SWI Instruction Timings
Mnemonic Minimum latency to first instruction of SWI exception handler
SWI 6
Table 42. Count Leading Zeros Instruction Timings
Mnemonic Minimum Issue Latency Minimum Result Latency
CLZ 1 1