AMD SB600 - Manual (Page 262)

©2008 Advanced Micro Devices, Inc. LPC ISA Bridge (Device 20, Function 3)
AMD SB600 Register Reference Manual Proprietary Page 262
SPI_RestrictedCmd2 Register- RW - 32 bits - [Mem_Reg 08h]
Field Name Bits Default Description
RestrictedCmdWoAddr
1 23:16 00h Same as RestrictedCmd0 except this command does not have
address
RestrictedCmdWoAddr
2 31:24 00h Same as RestrictedCmd0 except this command does not have
address
Note: For these registers either the SpiAccessMacRomEn and/or the SpiHostAccessRomEn bit is cleared;
RestrictedCmdWoAddr1 and RestrictedCmdWoAddr2, become read only and cannot be changed.
SPI_Cntrl1 Register- RW - 32 bits - [Mem_Reg 0Ch]
Field Name Bits Default Description
SPIParameters 7:0 00h This is the TX/RX FIFO port which can take up to 8 bytes. To
send data to SPI ROM, software writes data into this port. To
retrieve data that are received from the SPI ROM, software
reads from this port.
FifoPtr 10:8 000b This three bits show the internal pointer location
TrackMacLockEn 11 0b When set, the controller will lock the SPI for the MAC when it
has detected a command (from the MAC) matching the value
defined in offset 10h or 11h. Conversely, it will unlock the bus
when it has detected a command (from the MAC) matching the
value defined in offset 12h or 13h
NormSpeed 13:12 11b This defines the clock speed for the non-fast read command
00 – Reserved
01 – 33Mhz
10 – 22 Mhz
11 – 16.5Mhz
FastSpeed[1:0] 15:14 01b This defines the clock speed for the fast speed read.
00 – Reserved
01 – 33Mhz
10 – 22 Mhz
11 – 16.5Mhz
WaitClkInterval 21:16 22h Timing parameters used for SPI sharing protocol
SetLockCmd 22 0b Lock the SPI bus on the next transaction
SetUnlockCmd 23 0b Unlock the SPI bus on the next transaction
ByteProgramCmd 31:24 00h This is used to compare against the opcode sent out by the
MAC. This is a predefined value to decode for the BYTE
PROGRAM command.
SPI_CmdValue0 Register- RW - 32 bits - [Mem_Reg 10h]
Field Name Bits Default Description
MacLockCmd0 7:0 06h This is used to compare against the opcode sent out by the
MAC. If SPI_Cntrl1[11] is set, the controller will lock the SPI
bus for the MAC. In other words, the MAC has the exclusive
access to the ROM; access by the CPU will be delayed until
this is unlocked. This is to allow the MAC to do certain
sequence of operations without interruption.
MacLockCmd1 15:8 20h Same as MacLockCmd0
MacUnlockCmd0 23:16 04h This is used to compare against the opcode sent out by the
MAC. If SPI_Cntrl1[11] is set, the controller will unlock the SPI
bus for the MAC. In other words, access by the CPU will be
allowed again.
MacUnlockCmd1 31:24 04h Same as MacUnlockCmd0
Note Either the SpiAccessMacRomEn and/or the SpiHostAccessRomEn bit is cleared. All of these registers
become read only and cannot be changed.