2008-05-14 14:34:13 Memory Protection

Henning Manteuffel (GERMANY)

Message: 55833

I connected an FPGA to the Blackfin address/data bus for accelerating arithmetic computations.

Is there a way to unprotect certain addresses in user space so that the FPGA can be accessed directly without a device driver? Changing entries in the DCPLB address and data registers did not work, an exception is still thrown.

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2008-05-15 10:19:57 Re: Memory Protection

Mike Frysinger (UNITED STATES)

Message: 55862

by default, all the async memory banks are usable from userspace, so there isnt anything for you to change. i just tested by setting a pointer to 0x20000000 and reading data frorm userspace and it worked fine.

please post the crash message you're getting as well as information about your system (kernel/toolchain version/etc...)

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2008-05-22 08:20:14 Re: Memory Protection

Henning Manteuffel (GERMANY)

Message: 56140

I used the wrong toolchain (2007R1.1). Downgrading to 2007R1 eleminated the error. The toolchain seemed to be too new for the kernel.

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2008-05-22 10:13:08 Re: Memory Protection

Robin Getz (UNITED STATES)

Message: 56146

Henning:

Toolchain, kernel and bootloader are three pieces of the same puzzle. You can