AMD Geode LX 800@0.9W - Manual (Page 110)

110 AMD Geode™ LX Processors Data Book
CPU Core Register Descriptions 33234H
5.5.2 CPU Core Specific MSRs
5.5.2.1 Time Stamp Counter MSR (TSC_MSR)
5.5.2.2 Performance Event Counter 0 MSR (PERF_CNT0_MSR)
MSR Address 00000010h
Type R/W
Reset Value 00000000_00000000h
TSC_MSR Register Map
63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32
TSC (High DWORD)
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
TSC (Low DWORD)
TSC_MSR Bit Descriptions
Bit Name Description
63:0 TSC Time Stamp Counter. This register is the 64-bit time stamp counter, also readable via
the RDTSC instruction.
Bus Controller Configuration 0 Register (MSR 00001900h) contains configuration bits
that determine if TSC counts during SMM, DMM, or Suspend modes.
Writes to this register clears the upper DWORD to 0. The lower DWORD is written nor-
mally.
MSR Address 000000C1h
Type R/W
Reset Value 00000000_00000000h
PERF_CNT0_MSR Register Map
63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32
RSVD PERF_CNT0 (High Byte)
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
PERF_CNT0 (Low DWORD)
PERF_CNT0_MSR Bit Descriptions
Bit Name Description
63:40 RSVD Reserved. Write as read.
39:0 PERF_CNT0 Performance Event Counter 0. This register is a 40-bit event counter used to count
events or conditions inside of the CPU Core. This counter is controlled by Performance
Event Counter 0 Select MSR (MSR 00000186h).