2010-06-18 14:54:56     EBIU AMC problem on BF537

2010-06-18 14:54:56     EBIU AMC problem on BF537

Steven Vacca (UNITED STATES)

Message: 90428   

I am having a problem on my BF537 regarding the EBIU Asynchronous Memory Controller.

I am using the AWE, ARE, and ASM0 outputs on the 537 to communicate with a PLD.

I am using Bank 0 only.  I want to write a 16-bit word to several addrs in the range, 0x2000.0004 - 0x2000.0008.

Immediately after bootup, I set the EBIU regs (these are the default values) , well before any writes to addr 0x2000.0008, for example, as follows:

        bfin_write_EBIU_AMBCTL0(0xffc2ffc2);

        bfin_write_EBIU_AMBCTL1(0xffc2ffc2);

        bfin_write_EBIU_AMGCTL(0x00f2);

      

Within seconds after my app starts running, I can write to addr 0x2000.0008 several

times for a few seconds, and with a scope can see that the AWE and AMS0 outputs are

active, but after that, they remain inactive no matter how many times I write to

0x2000.0008. Even if I constantly write to addr 0x2000.0008 at bootup, after a fews

secs the AWE and AMS) outputs still stop outputting anything.  What am I missing here?

A typical write to addr 0x2000.0008 is:

        *((UINT_16*) 0x20000008) = 0x0001;

Thanks.

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2010-06-18 15:15:16     Re: EBIU AMC problem on BF537

Robin Getz (UNITED STATES)

Message: 90430   

Steven:

Is this in U-Boot or the kernel? or userspace?

-Robin

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2010-06-21 09:25:18     Re: EBIU AMC problem on BF537

Steven Vacca (UNITED STATES)

Message: 90505   

After U-Boot executes, then the kernel comes up and loads my app.  My app executes calls to my kernel driver which does the writes to the addr 0x2000.0008. Sometimes I see output signals for less than a second, other times I see none.

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2010-06-21 11:33:57     Re: EBIU AMC problem on BF537

Mike Frysinger (UNITED STATES)

Message: 90512   

why are you reprogramming the async settings that way ?  the kernel kconfig has a field where you may specify the default async states under the Blackfin options.

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2010-06-21 11:50:21     Re: EBIU AMC problem on BF537

Steven Vacca (UNITED STATES)

Message: 90514   

I may have found an anomaly with my scope. I'll reply again if I am still having a problem. Thanks.