AMD SB600 - Manual (Page 93)

©2008 Advanced Micro Devices, Inc. OCHI USB 1.1 and EHCI USB 2.0 Controllers
AMD SB600 Register Reference Manual Proprietary Page 93
Control register (EHCI_PCI_CFG xE4[28:16], default = 0E0h), regardless of the value in register (MEM_Reg:
00h).
Registers Name Offset Address
Control / Status DBase + 00h
USB PIDs DBase + 04h
Data Buffer DBase + (08h~0Ch)
Device Address DBase + 10h
Control / Status – RW - 32 bits - [DBUG_Reg : DBase + 00h]
Field Name Bits Default Description
Data Length 3:0 0h For write operations, this field is set by software to indicate to the
hardware how many bytes of data in Data Buffer are to be transferred
to the console when Write/Read# is set when software sets Go. A
value of 0h indicates that a zero-length
packet should be sent. A value
of 1-8 indicates 1-8 bytes are to be transferred. Values 9-Fh are illegal
and how hardware behaves if used is undefined.
For read operations, this field is set by hardware to indicate to software
how many bytes in Data Buffer are valid in response to software setting
Go
when Write/Read# is cleared. A value of 0h indicates that a zero
length packet was returned. (The state of Data Buffer is not defined.)
A value of 1-8 indicates 1-8 bytes were received. Hardware is not
allowed to return values 9-Fh. The transferring of data always starts
with byte 0 in the data area and moves toward byte 7 until the transfer
size is reached.
Write/Read# 4 0b Software sets this bit to indicate that the current request is a write and
clears it to indicate a read.
Go 5 0b Software sets this bit to cause the hardware to perform a request.
Writing this bit to a 1 when the bit is already set may result in undefined
behavior. Writing a 0 to this bit has no effect. When set, the hardware
clears this bit when the hardware sets the Done bit. (Completion of a
request is indicated by the Done bit.)
Error/Good# 6 0b Read Only
Updated by hardware at the same time it sets the Done bit. When set it
indicates that an error occurred. Details of the error are provided in the
Exception
field. When cleared, it indicates that the request terminated
successfully.
Exception 9:7 000b Read Only
This field indicates the exception when Error/Good# is set. This field
cannot be cleared by software. Reset default = 000b.
Value Meaning
000b None
001b Transaction error: indicates the USB2 transaction
had an error (CRC, bad PID, timeout, etc.)
010b HW error. Request was attempted (or in progress)
when the port was suspended or reset.
011b-111b Reserved
In Use 10 0b Set by software to indicate that the port is in use. Cleared by software
to indicate that the port is free and may be used by other software.
(This bit has no affect on hardware.)
Reserved 15:11 Reserved
Done 16 0b RWC
This bit is set by HW to indicate that the request is complete. Writing a
1 to this bit will clear it. Writing a 0 to this bit has no effect.
Reserved 27:17 Reserved