AMD Geode LX 600@0.7W Data Book page 525

Security Block Register Descriptions
6.12.3.9 SB Length B (SB_LENGTH_B)
SB Memory Offset 028h
Type R/W
Reset Value 00000000h
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10
Bit Name
31:4 LENGTH_B
3:0 RSVD
6.12.3.10 SB Writable Key 0 (SB_WKEY_0)
SB Memory Offset 030h
Type WO
Reset Value 00000000h
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10
Bit Name
31:0 WKEY_ 0
AMD Geode™ LX Processors Data Book
SB_LENGTH_B Register Map
LENGTH_B
SB_LENGTH_B Register Bit Descriptions
Description
Length B. The Length field is a 32-bit value that describes the number of bytes to be
encrypted or decrypted in the next operation using pointer set B. The lower four bits
must be written as zero and always read zero. This forces the data length to be an inte-
ger number of 16-byte blocks. This register should not be changed during an AES
encryption or decryption operation using the A pointer set (i.e., while STA is asserted,
SB Memory Offset 000h[0] = 1). This register can be modified during an operation using
the B pointer set (while STB is asserted, SB Memory Offset 004h[0] = 1).
Reserved. Set to 0.
SB_W_KEY0
W_EY_0[31:0]
Bit Descriptions
SB_WKEY_0
Description
Writable Key 0. Bits [31:0] of the Writable Key for the Security Block. This register
should not be changed during an AES encryption or decryption operation. To prevent
one process from reading the key written by another process, this register is not read-
able.
9
Register Map
9
33234H
8 7 6 5 4 3 2 1
RSVD
8 7 6 5 4 3 2 1
0
0
525