Am Samstag, 19. Januar 2013 schrieb Stan Hoeppner: > > PS: do you know if, as for 16 bits to 32 bits, there is a the need to > > switch processor's "mode"? > > Yes. x86-64 adds 'long' mode which comprises two sub-modes. See the > Wikipedia page or the x86-64 Architectural Programmer's Reference Manual > for details.
You can see whether the CPU has this longmode in Linux: martin@merkaba:~> egrep --colour=always "(model|lm)" /proc/cpuinfo | head -3 model : 42 model name : Intel(R) Core(TM) i5-2520M CPU @ 2.50GHz flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp >>> lm <<< constant_tsc arch_perfmon pebs bts nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic popcnt tsc_deadline_timer aes xsave avx lahf_lm ida arat epb xsaveopt pln pts dtherm tpr_shadow vnmi flexpriority ept vpid This is a good way to see whether a CPU is capable of 64-bit stuff. lspcu also shows the supported modes: martin@merkaba:~> lscpu Architecture: x86_64 CPU op-mode(s): 32-bit, 64-bit Byte Order: Little Endian CPU(s): 4 On-line CPU(s) list: 0-3 Thread(s) per core: 2 Core(s) per socket: 2 Socket(s): 1 NUMA node(s): 1 Vendor ID: GenuineIntel CPU family: 6 Model: 42 Stepping: 7 CPU MHz: 800.000 BogoMIPS: 4983.77 Virtualization: VT-x L1d cache: 32K L1i cache: 32K L2 cache: 256K L3 cache: 3072K NUMA node0 CPU(s): 0-3 Ciao, -- Martin 'Helios' Steigerwald - http://www.Lichtvoll.de GPG: 03B0 0D6C 0040 0710 4AFA B82F 991B EAAC A599 84C7 -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/201301191604.46998.mar...@lichtvoll.de
