Intel 6 SERIES CHIPSET - DATASHEET 01-2011 - Memory-Mapped Registers

Datasheet 799
High Precision Event Timer Registers
20 High Precision Event Timer
Registers
The timer registers are memory-mapped in a non-indexed scheme. This allows the
processor to directly access each register without having to use an index register. The
timer register space is 1024 bytes. The registers are generally aligned on 64-bit
boundaries to simplify implementation with IA64 processors. There are four possible
memory address ranges beginning at 1) FED0_0000h, 2) FED0_1000h, 3)
FED0_2000h, 4) FED0_3000h. The choice of address range will be selected by
configuration bits in the High Precision Timer Configuration Register (Chipset Config
Registers:Offset 3404h).
Behavioral Rules:
1. Software must not attempt to read or write across register boundaries. For
example, a 32-bit access should be to offset x0h, x4h, x8h, or xCh. 32-bit accesses
should not be to 01h, 02h, 03h, 05h, 06h, 07h, 09h, 0Ah, 0Bh, 0Dh, 0Eh, or 0Fh.
Any accesses to these offsets will result in an unexpected behavior, and may result
in a master abort. However, these accesses should not result in system hangs. 64-
bit accesses can only be to x0h and must not cross 64-bit boundaries.
2. Software should not write to Read Only registers.
3. Software should not expect any particular or consistent value when reading
reserved registers or bits.
20.1 Memory Mapped Registers
Table 20-1. Memory-Mapped Registers (Sheet 1 of 2)
Offset Mnemonic Register Default Type
000–007h GCAP_ID General Capabilities and Identification
0429B17F8
086A201h
RO
008–00Fh — Reserved — —
010–017h GEN_CONF General Configuration
00000000
00000000h
R/W
018–01Fh — Reserved — —
020–027h GINTR_STA General Interrupt Status
00000000
00000000h
R/WC,
R/W
028–0EFh — Reserved — —
0F0–0F7h MAIN_CNT Main Counter Value N/A R/W
0F8–0FFh — Reserved — —
100–107h TIM0_CONF Timer 0 Configuration and Capabilities N/A R/W, RO
108–10Fh TIM0_COMP Timer 0 Comparator Value N/A R/W
110–11Fh — Reserved — —
120–127h TIM1_CONF Timer 1 Configuration and Capabilities N/A R/W, RO
128–12Fh TIM1_COMP Timer 1 Comparator Value N/A R/W