Freescale Semiconductor MPC5553 - Functional Description

MPC5553/MPC5554 Microcontroller Reference Manual, Rev. 5
Freescale Semiconductor 16-3
16.3 Functional Description
16.3.1 BAM Program Resources
The BAM program uses/initializes following MCU resources:
• The BOOTCFG field in the reset status register (SIU_RSR) to determine the boot option.
• The location and value of the reset configuration halfword (RCHW) to determine the location of
boot code and the boot configuration options. Refer to Chapter 4, “Reset” for information about
the RCHW.
• The DISNEX bit in the SIU_CCR to determine if the Nexus port is enabled.
• The MMU to allow core access to the MCU internal resources and external bus.
• The EBI registers and external bus pads, when performing external boot modes.
• The CAN_A, eSCI_A and their pads, when performing serial boot mode.
• The eDMA during serial boot mode.
16.3.2 BAM Program Operation
BAM is accessed by the MCU core after the negation of RSTOUT, before user code starts.
First, the BAM program configures e200z6 core MMU to allow access to all MCU internal resources and
external memory space, according the Table 16-2. This MMU setup remains the same for internal flash
Boot mode.
0xFFFF_D000–
0xFFFF_DFFF
BAM Program Mirrored
0xFFFF_E000–
0xFFFF_EFFF
BAM Program Mirrored
0xFFFF_F000–
0xFFFF_FFFF
BAM Program
Table 16-2. MMU Configuration for Internal Flash Boot
TLB
Entry
Region
Logical Base
Address
Physical Base
Address
Size Attributes
0 Peripheral Bridge B and
BAM
0xFFF0_0000 0xFFF0_0000 1 MB Cache inhibited
Guarded
Big Endian
Global PID
1 Internal flash 0x0000_0000 0x0000_0000 16 MB Cache enabled
Not guarded
Big Endian
Global PID
2 EBI 0x2000_0000 0x2000_0000 16 MB Cache enabled
Not guarded
Big Endian
Global PID
Table 16-1. BAM Memory Map (Continued)