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Silicon Updates

SPRZ293A—November 2009 TMS320C6457 Fixed-Point Digital Signal Processor Silicon Errata 9

www.ti.com

Submit Documentation Feedback Silicon Revisions 1.0, 1.1, 1.2, 1.3, 1.4 .

Advisory 1 EMAC Boot Issue

Revision(s) Affected: 1.1, 1.0

Details: The EMAC ready announcement frame is not transmitted when the C6457 device is

booted in master and slave modes.

When the DSP is booted in EMAC master/slave boot modes (boot modes 4, 5), the DSP

transmits an Ethernet Ready Announcement (ERA) frame in the form of a BOOTP

request. The BOOTP request is intended to inform the host server that the DSP is ready

to receive boot packets. The ERA frame packet is described in more detail in the TI

User’s Guide TMS320C645x/C647x DSP Bootloader (literature number SPRUEC6).

Texas Instruments will fix the Ethernet Ready Announcement frame transmission in

the next silicon revision for C6457 device.

Workaround 1: Have the host that is responsible for sending the boot packets broadcast a small boot

table with the program that is shown in the example below. This will cause any C6457

device to restart the EMAC boot procedure (without configuring the MAC peripheral

again) and re-transmit the ERA.

Re-send ERA packet code:

BOOT_REENTRY_ADDR .equ 03c000110h

BOOT_EMAC_OPT .equ 01088480Ah

MVKL BOOT_EMAC_OPT, A1

MVKH BOOT_EMAC_OPT, A1

MVKL 0x00000026, A4 ;overwrite option field in EMAC bootparam

MVKH 0x00000026, A4

STH A4, *A1

NOP 4

MVKL BOOT_REENTRY_ADDR, B3

MVKH BOOT_REENTRY_ADDR, B3

BNOP B3, 5

Workaround 2: The host server would need to rely on prior knowledge of the DSP MAC address to

transmit boot packets to the correct DSP. The DSP will be ready to receive EMAC boot

packets within 2 ms following deassertion of reset.

In the scenario where the boot server reads the MAC address of the DSP from the ERA

packet, the procedure would need to be changed. After some customer dependant delay

where the ERA is not received, the host sends the broadcast packet with the payload

described in Workaround 1.

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