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Altera_Forum
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16 years ago

How to finish the altpciechdma.c driver?

I've downloaded the altpciechdma.c driver for the Altera Arria GX dev kit. The char part of it is not yet finished (due to the comments). And a module is missign "mapper_user_to_sg.h". Smb has...
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Altera_Forum
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13 years ago

Hi Haulisson.

After checking the document, I think the DMA core you're using is not the one the kernel module is designed to use.

The 'altpciechdma.c' is oriented for the chaining DMA core, which I don't exactly know where it is described, but you can find references to it in the chapter 15 of 'IP Compile for PCI Express User Guide' Altera document.

But I believe the document you showed me uses the standard DMA core. When instantiating the DMA core in the Qsys, click in the button 'Documentation' to get its datasheet. I believe you'll find that the registers configured by the kernel module do not match those of the datasheet.

If that's the case, you might have to alter the module's 'dma_test' function yourself, to configure the DMA core registers.

Best regards,

Pedro