AMD Geode LX 800@0.9W - Manual (Page 554)

554 AMD Geode™ LX Processors Data Book
GeodeLink™ Control Processor Register Descriptions 33234H
6.14.2.13 GLCP System Reset and PLL Control (GLCP_SYS_RSTPLL)
This register is initialized during POR, but otherwise is not itself reset by any “soft-reset” features. Note that writing this reg-
ister always has immediate effect, so read-modify-writes must be done to avoid corrupting the PLL timing settings. When
using this register functionally to change PLL frequencies, the CHIP_RESET bit (bit 0) should be set. Writing this register
with the CHIP_RESET bit set will never send a write-response over the GLIU (this allows halting bus traffic before the reset
occurs).
MSR Address 4C000014h
Type R/W
Reset Value Bootstrap specific
GLCP_SYS_RSTPLL 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 GLIUMULT
MBDIV
COREMULT
COR
E
DIV
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
SWFLAGS
GLIULOCK CORELOCK
HOLD_COUNT
RSVD
GLIUPD
COREPD
GLIUBYP
A
S
S
COREBYP
A
S
S
LPF
E
N
V
A
_
S
EM
I_
SY
N
C
_
M
O
D
E
PCI_SEMI_SYNC_MODE
BOOTSTRAPS
CHIP_RESET
GLCP_SYS_RSTPLL Bit Descriptions
Bit Name Description
63:44 RSVD Reserved.
43:39 GLIUMULT GLIU Multiplier (Bootstrap Dependent, see Table 6-87).
00000: Multiply by 1,....
11111: Multiply by 32.
38 GLIUDIV GLIU Divide. When set, predivide the GLIU PLL input frequency by 2.
0: Do not predivide input. (Default)
1: Divide by 2.
37:33 COREMULT CPU Core Multiplier (bootstrap dependent, see Table 6-87 on page 556).
00000: Multiply by 1,....
11111: Multiply by 32.
32 COREDIV CPU Core Divide. When set, predivide the GLIU PLL input frequency by 2.
0: Do not predivide input. (Default)
1: Divide by 2.
31:26 SWFLAGS Flags. Flags that are reset only by the POR# signal, not the CHIP_RESET (bit 0). They
are reset to 0 and can be used as flags in the boot code that survive CHIP_RESET.
25 GLIULOCK (RO) Lock (Read Only). Lock signal from the system PLL. The worst-case lock time for a
AMD Geode™ LX processor PLL is 100 µs.
24 CORELOCK
(RO) Lock (Read Only). Lock signal from the system PLL. The worst-case lock time for a
AMD Geode LX processor PLL is 100 µs.