ioat3: dca and raid operations are incompatible

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / dma / ioat / dma_v3.c

diff --git a/drivers/dma/ioat/dma_v3.c b/drivers/dma/ioat/dma_v3.c
index 35d1e33afd5b9c3bf7a185d3f9df5b37747dacf6..4f305f61f8784fe5c23494fecc542e5dccbc43a2 100644 (file)
--- 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;