
during PORESET_B, such as RCW_SRC in DUTCFG0. Changes to DUTCFG registers only take effect on the next reset or
reconfiguration event. The following figure shows the configuration hardware arrangement.
Figure 24. Configuration sampling
Note that switches cause a short to ground when closed. To make it easier to set and read switches, values are inverted in the
CPLD, so that when a switch is on, the value used is 1.
All switches can be read from software to easily determine the system configuration for reporting purposes (see the "Core
Management Space Registers" section of the "CPLD Programming Model" chapter).
The table below describes the LS1028A configuration signals.
Table 25. Processor configuration settings
Configuration signal
LS1028A primary
signal
DIP switch
CPLD register
Description
CFG_RCW_SRC0
UART2_SOUT
SW1[1:4]
DUTCFG0[3:0]
Specifies RCW fetch location
CFG_RCW_SRC1
UART1_SOUT
CFG_RCW_SRC2
ASLEEP
CFG_RCW_SRC3
CLK_OUT
TEST_SEL_B
TEST_SEL
SW3[1]
DUTCFG2[0]
Silicon variations
CFG_SVR[0:1]
XSPI_CS0_B
XSPI0_CS1_B
-
DUTCFG2[2:1]
-
CFG_ENG_USE0
XSPI_SCK
-
DUTCFG11[7]
Configures processor to use
differential SYSCLK.
1. TEST_SEL_B is a static signal (constantly driven), unlike most other processor configuration signals.
All other configuration signals are static and unrelated to the processor. The following table summarizes these configuration
signals.
Table 26. Non-processor configuration settings
Configuration signal
DIP switch
CPLD register
Description
CFG_XSPI_MAP
SW1[8]
BRDCFG0[6]
Controls how XSPI_A chip-select 0 is connected
to devices/peripherals.
CFG_MEM_WP
SW3[4]
CTL[3]
Allows/prevents write to SYSTEM ID, UEFI flash,
and DDR4 SPD.
Table continues on the next page...
System controller
QorIQ LS1028A Reference Design Board Reference Manual, Rev. b, 11/2018
NXP Semiconductors
COMPANY CONFIDENTIAL
47
Содержание QorIQ LS1028A
Страница 111: ......