From 228c4f5cfbf1cda411d9aa7204a612a63c89b1e8 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Thu, 19 Nov 2009 17:07:10 -0700 Subject: ioat3: dca and raid operations are incompatible RAID operations cause a system hang on platforms with DCA (Direct-Cache-Access) enabled. So turn off RAID capabilities in this case. Signed-off-by: Dan Williams --- drivers/dma/ioat/dma_v3.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'drivers/dma/ioat/dma_v3.c') diff --git a/drivers/dma/ioat/dma_v3.c b/drivers/dma/ioat/dma_v3.c index 35d1e33afd5..4f305f61f87 100644 --- a/drivers/dma/ioat/dma_v3.c +++ b/drivers/dma/ioat/dma_v3.c @@ -1117,6 +1117,7 @@ static int __devinit ioat3_dma_self_test(struct ioatdma_device *device) int __devinit ioat3_dma_probe(struct ioatdma_device *device, int dca) { struct pci_dev *pdev = device->pdev; + int dca_en = system_has_dca_enabled(pdev); struct dma_device *dma; struct dma_chan *c; struct ioat_chan_common *chan; @@ -1137,6 +1138,11 @@ int __devinit ioat3_dma_probe(struct ioatdma_device *device, int dca) dma->device_prep_dma_interrupt = ioat3_prep_interrupt_lock; cap = readl(device->reg_base + IOAT_DMA_CAP_OFFSET); + + /* dca is incompatible with raid operations */ + if (dca_en && (cap & (IOAT_CAP_XOR|IOAT_CAP_PQ))) + cap &= ~(IOAT_CAP_XOR|IOAT_CAP_PQ); + if (cap & IOAT_CAP_XOR) { is_raid_device = true; dma->max_xor = 8; -- cgit v1.2.3