RM0082
HS_USB2.0 host
Doc ID 018672 Rev 1
423/844
22.6.7 HCCPARAMS
register
The HCCPARAMS is a RO register stating the capability parameters of the EHCI host
controller, such as scheduling, addressing, etc. The HCCPARAMS register bit assignments
are given in
[04]
PPC
1’h1
Port power control.
This field indicates whether the EHCI host controller
implementation includes port power control. In
particular, setting this bit a port power switch is
enabled for each port, otherwise (PPC set to 1‘b0)
each port is hard-wired to power.
Note: The value of this field affects the functionality of
the port power field (PP) in each port status control
registers of auxiliary power well.
[03:00]
N_PORTS
4’h2
Number of physical downstream ports.
This field specifies the number of physical
downstream ports implemented on this EHCI host
controller. The value of this field (ranging from 4’h1 to
4’hF, that is 1 to 15) determines how many port
registers are addressable in the auxiliary power well
registers memory-space (ranging from offset 0x40 to
0x7C with respect to USBOPBASE address).
Note: A zero-value in this field is undefined.
Table 352.
HCSPARAMS register bit assignments (continued)
Bit
Name
Reset value Description
Table 353.
HCCPARAMS register bit assignments
Bit
Name
Reset value Description
[31:16]
Reserved
-
Read: undefined.
[15:08]
EECP
8’hA0
EHCI extended capabilities pointer.
This optional field indicates the existence of a
capabilities list. A zero value indicates that no
extended capabilities are implemented, whereas a
non-zero value indicates the offset in PCI
configuration space of the first EHCI extended
capability.
Note: The pointer value in this field must be 8’h40 or
greater in order to maintain the consistency of the
PCI header defined for this class of device.