Messages in this thread | | | Subject | Re: Can I/OAT DMA engineer access PCI MMIO space | From | "Koul, Vinod" <> | Date | Tue, 03 May 2011 09:42:06 +0530 |
| |
On Tue, 2011-05-03 at 10:21 +0800, 康剑斌 wrote: > >> I try to use ioatdam to copy data from system memory to pci MMIO space: > >> If dst points to a memory space, the operation would pass. > >> But if dst points to a pci MMIO space, it failed with kernel oops. > >> It seems the code: > >> BUG_ON(is_ioat_bug(chanerr)); > >> in drivers/dma/ioat/dma_v3.c, line 365 cause the oops. > >> Is there anyway to access pci MMIO space using ioat? > >> The datasheet says that ioat supports MMIO access. > > Did you map the IO memory in kernel using ioremap and friends first? > > > yes, I had used 'ioremap_nocache' to map the IO memory and I can use > memcpy to copy data to this region. The async_tx should have been > correctly configured as > I can use aync_memcpy to copy data between different system memory address. Then you should be using memcpy_toio() and friends
~Vinod
-- ~Vinod
-- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |