Functional Description
14.3.1.2.1 Modes of Operation
The device has two modes of operation concerning the reset of the 3PSW Ethernet switch.
The mode is controlled by the ISO_CONTROL bit in RESET_ISO register of the device control
module.This bit should default to '0'. Writes to the ISO_CONTROL bit must be supervisor mode writes.
Mode 1: ISO_CONTROL=0 (reset isolation disabled)
•
This mode is selected when ISO_CONTROL bit of control module is = 0. This should be the default
state of the bit after control module reset.
•
Upon any device level resets, the entire CPSW_3GSS_R IP, L3/L4, control module (including all pin
mux control and the ISO_CONTROL bit) is immediately reset.
Mode 2: ISO_CONTROL=1 (reset isolation enabled)
•
This mode is selected when ISO_CONTROL bit of control module is = 1.
•
Upon any device reset source other than POR pin or ICEPICK cold (so this includes SW global cold,
any watchdog reset, warm RESETn pin, ICEPICK warm, SW global warm), the following should be
true:
–
The CPSW_3GSS_R is put into ‘isolate’ mode and non-switch related portions of the IP are reset.
–
The 50-MHz and 125-MHz reference clocks to the 3PSW Ethernet Subsystem remains active
throughout the entire reset condition.
–
The control for pin multiplexing for all of the signals should maintain their current configuration
throughout the entire reset condition.
–
The reset isolated logic inside 3PSW Ethernet Subsystem IP which maintains the switch
functionality
–
•
Upon any cold reset sources, the entire 3PSW Ethernet Subsystem, control module (including all pin
mux control and the ISO_CONTROL bit itself) is reset.
1177
SPRUH73H – October 2011 – Revised April 2013
Ethernet Subsystem
Copyright © 2011–2013, Texas Instruments Incorporated