Peripheral Booting
Initialize peripheral and
ping the host
Does the host
respond?
No
Yes
Boot Failed. Return to
framework to try next
device in the device list.
Transfer control to
0x402F0400 (GP)
Start image transfer from
host to OCMC RAM
Transfer
completed
successfully?
Yes
No
Functional Description
Table 26-31. Blocks and Sectors Searched on Non-XIP Memories
Memory
Maximum Number of Blocks Checked
Number of Sectors Searched
NAND
first 4
Number of sectors in one block
(1)
SPI, eMMC/eSD and MMC/SD cards (raw
first 4
1
mode)
(1)
Depends on NAND geometry
Regarding MMC/SD card booting in FAT mode, the file system area is searched for one file.
26.1.8 Peripheral Booting
26.1.8.1 Overview
The ROM Code can boot from three different peripheral interfaces:
•
EMAC: 1000/100/10 Mbps Ethernet, using standard TCP/IP network boot protocols BOOTP and TFTP
•
USB: Full speed, client mode
•
UART: 115.2Kbps, 8 bits, no parity, 1 stop bit, no flow control
The purpose of booting from a peripheral interface is to download a boot image from an external host
(typically a PC). This booting method is mostly used for programming flash memories connected to the
device (e.g. in the case of initial flashing, firmware update or servicing).
26.1.8.2 Boot Image Location and Size
The boot image is downloaded directly into internal RAM at the location 0x402F0000 on GP devices. The
maximum size of downloaded image is 109 KB.
26.1.8.3 Peripheral Boot Procedure Overview
Figure 26-23. Peripheral Booting Procedure
4143
SPRUH73H – October 2011 – Revised April 2013
Initialization
Copyright © 2011–2013, Texas Instruments Incorporated