AMD Geode LX 800@0.9W - Manual (Page 187)

AMD Geode™ LX Processors Data Book 187
CPU Core Register Descriptions 33234H
5.5.2.95 L2 Cache Configuration MSR (L2_CONFIG_MSR)
L2_CONFIG_MSR controls the behavior of the L2 cache.
MSR Address 00001920h
Type R/W
Reset Value 00000000_0000000Eh
L2_CONFIG_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
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
RSVD L2_IM_LOCK L2_DM_LOCK RSVD
L2_T
A
G
_CL
K
GT
_E
N
L2
_P
A
SS_IOMSR
L2
_DMEVCT_D
IR
T
Y
L2_W
AIT_
DM_WR
L2_INV
A
L
ID
L
2_IM_ALLOC_EN
L2_DM_ALL
O
C_
E
N
L2_ALLOC_EN
L2_EN
L2_CONFIG_MSR Bit Descriptions
Bit Name Description
63:24 RSVD Reserved.
23:20 L2_IM_LOCK L2 Instruction Memory Subsystem Lock. On allocations from the IM, avoid using the
ways that have the corresponding bits set to 1. (Default = 0)
19:16 L2_DM_LOCK L2 Cache Data Memory Subsystem Lock. On allocations from the DM, avoid using the
ways that have the corresponding bits set to 1. (Default = 0)
15:9 RSVD Reserved.
8 L2_TAG_
CLKGT_EN L2 Cache Tag Clock Gating Enable. If set, the L2 tags would be clocked only when
accessed. Otherwise, the tags would be clocked whenever the bus controller clocks are
active. (Default = 0)
7 L2_PASS_
IOMSR L2 Cache (always) Pass I/Os and MSRs. Reserved for Debug only. Pass I/Os and
MSRs through regardless of the state of the L2. (Default = 0)
6 L2_DMEVCT_
DIRTY L2 Cache Data Memory Subsystem Evictions (always) Dirty. Reserved for Debug
only. Treats all DM evictions as dirty. (Default = 0)
5 L2_WAIT_DM_
WR L2 Cache Wait for Data Memory Subsystem Writes. Reserved for debug only. Waits
for all data beats from DM before proceeding. (Default = 0)
4 L2_INVALID L2 Cache Invalidate. Invalidate the entire contents of the L2 cache. This bit always
reads back as 0. (Default = 0)
3 L2_IM_ALLOC_
EN L2 Cache Instruction Memory Subsystem Allocation Enable. A new IM access is
allocated into the L2 cache only if this bit is on. (Default = 1)
2 L2_DM_ALLOC
_EN L2 Cache Data Memory Subsystem Allocation Enable. A new DM access is allocated
into the L2 cache only if this bit is on. (Default = 1)
1 L2_ALLOC_EN L2 Cache Allocation Enable. A new line is allocated into the L2 cache only if this bit is
on (Default = 1)
0 L2_EN L2 Cache Enable. If this bit is on, the arbiter redirects memory accesses to the L2 block.
(Default = 0)