Quick Comparison - laysim-GR740 vs Simics LEON4
I got a chance to use Simics LEON4 from WindRiver. I expected that Simics LEON4 would show high performance, but the actual performance was very slow compared to laysim-gr740-dbt . And the GRLIB models of GR740 which are implemented in Simics LEON4 are very limited. (No IRQAMP extension, IOMMU, and MMU-TLB, and no power-down mode support) I could not run RCC-1.3 examples, RTEMS 5.1 SMP examples, and XtratuM hypervisor in Simics LEON4 because of the lack of GRLIB modeling. When Simics LEON4 accesses the unimplemented registers of GRLIB, it halts with reporting "Address not mapped". To overcome this problem temporarily, I added the unimplemented registers of GRLIB into outside_memory_whitelist[], but it could run only a few examples of RTEMS 5.1 SMP. Also XtratuM hypervisor was not executed correctly in Simics LEON4 either. However, VxWorks 6.9 and 7 for GR740 could run without any problem in Simics LEON4. More detailed information can be found in " Quick Comparison with ...