Hello, I have a question on enabling DMA access to IDE hard disk using VIA vt82c686 chipset. My platform is a single board computer AAEON PCM-6892 (VIA C3 CPU, via vt82c686b chipset). I am working on a IDE-DMA port to RTEMS. I am trying to find which irq number the IDE bus master controller (part of the vt82c686 chipset) uses. I read out PCI_INTERRUPT_PIN and PCI_INTERRUPT_LINE from its PCI configuration space. The PCI_INTERRUPT_PIN is found to be '0', and PCI_INTERRUPT_LINE as 'FF'. Does it mean this controller does not support interrupt? If so, who do I tell if the DMA transfer finishes?? The experiment I did is to send ATA_COMMAND_READ_DMA to IDE0 command register (I/O address 0x1F7) and then write '1' to the last bit of IDE BM controller's command register (first register in the BM IDE I/O space) to start DMA transfer. But the DMA transfer hangs the system. I have installed an interrupt handler for IRQ 14, which seems not triggered. Please advise. Thanks, Yan - : send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
