DM6467t and 512M DDr

beyond.cheng

We use DM6467T and 512M DDR memory,DSP(not ARM) can access DDR memory from 257M to 512M,but the speed is very slow,it is about 1/20 speed accessing DDR from 0M to 256M.We think it's probable that the cache is not mapping for the upper DDR range.If it’s true,how to map the upper DDR range? Can some help me ?

Thanks a lot.

Note:the paltform: linux2. 6.32 dvsdk_3_10_00_16

over 14 years ago

0 Ian Cassias over 11 years ago

Prodigy 100 points

Hello,

I am seeing a similar issue on a custom board with 512MB of DDR memory. If I set the DSP to operate out of the lower 256 MB, everything seems to operate at normal speed. However, when operating out of the upper memory range the performance is severely degraded.

Is there a setting somewhere that is needed to get the additional memory to function at full speed?

Thanks,

Ian

0 Ian Cassias over 11 years ago in reply to Ian Cassias

Prodigy 100 points

The solution for me was to set the following:

prog.module("GBL").C64PLUSMAR128to159 = 0xFFFFFFFF;

in the file:

dvsdk_3_10_00_19/cs2dm6467_1_00_00_10/packages/ti/sdo/server/cs/server.tcf

This apparently makes the additional 256 MB of DDR cacheable by the DSP. The solution was gleaned from one of the posts in the following thread:

http://e2e.ti.com/support/dsp/davinci_digital_media_processors/f/99/t/161015.aspx

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DM6467t and 512M DDr