PA-RISC Processors processor
PA-8800 (Mako)
Overview
The dual-core PA-8800 Mako processor, introduced in 2004, is a PA-RISC 2.0 64-bit processor from HP that integrated two seperate PA-8700 cores on a single die with very large off-die L2 caches. The clock speed was only increased slightly, while the processor bus interface was redesigned to use the Itanium 2 bus. Mako was supposed to breathe fresh life in the PA-RISC line, though it had strong internal competition from the Itanium line, a VLIW development from HP and Intel, and was not marketed much. Most systems supporting PA-8800s use the HP zx1 chipset and could be hardware-upgraded to use Itanium 2 IA64 processors.
Details
- PA-RISC version 2.0, 64-bit architecture, multi-processor capable, 4-way superscalar
- Two cores and ten functional units per core: 2 integer ALUs, 2 shift/merge units, 2 complete load/store pipelines, 2 Floating Point multiply/accumulate units, 2 Floating Point divide/square root units
- IRB: 56-entry instruction queue/reorder buffer
- TLB: 240-entry fully-associative dual-ported per core
- BTAC: 32-entry Branch Target Address Cache; BHT: 2048-entry Branch History Table per core
- Cache 0.75 MB instruction and 0.75 MB data L1 per core on-chip, 4-way set associative
- Cache 32 MB L2 off-chip, four 8 MB DDR-ESRAM chips, 300 MHz clock, each 2.7 GB/s bandwidth
- Cache L2 is shared between the cores, L2 controller is on-chip
- Memory up to 16 TB supported with 44-bit physical addresses
- Memory and I/O controllers are external
- Bi-endian support
- MAX-2 multimedia extensions subword arithmetic for multimedia applications
- Itanium 2 processor bus, 200 MHz clock, 128-bit, 6.4 GB/s bandwidth
- Up to 1 GHz clock speed with 1.5 V core voltage
- 23.6×15.5 mm2 die, 300,000,000 FETs, 0.13µ, 8-layer Silicon-on-Insulator CMOS fabbed by IBM
Used in
- HP C8000 workstations
- HP 9000 L1500-9X (rp5430), L2000-9X (rp5450) servers
- HP 9000 N4000-9X (rp7405, rp7410) servers
- HP 9000 rp3410, rp3440 servers
- HP 9000 rp4410, rp4440 servers
- HP 9000 rp7420 servers
- HP 9000 rp8400, rp8410, rp8420 servers
- HP 9000 Superdome mainframes (SD16A, SD32A, SD64A)
References
- HP’s Mako Processor (PDF, 1.4 MB)
- David J. C. Johnson (2001: Microprocessor Forum).