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| author | Dan Williams <dan.j.williams@intel.com> | 2009-09-08 12:01:04 -0700 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2009-09-08 17:30:24 -0700 |
| commit | 4fb9b9e8d55880523db550043dfb204696dd0422 (patch) | |
| tree | 733a672aeb819bb8133b16329a6b5088cf9ee693 /drivers/dma/ioat/dma_v2.c | |
| parent | 6df9183a153291a2585a8dfe67597fc18c201147 (diff) | |
| download | linux-4fb9b9e8d55880523db550043dfb204696dd0422.tar.gz linux-4fb9b9e8d55880523db550043dfb204696dd0422.tar.bz2 linux-4fb9b9e8d55880523db550043dfb204696dd0422.zip | |
ioat: cleanup completion status reads
The cleanup path makes an effort to only perform an atomic read of the
64-bit completion address. However in the 32-bit case it does not
matter if we read the upper-32 and lower-32 non-atomically because the
upper-32 will always be zero.
Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/dma/ioat/dma_v2.c')
| -rw-r--r-- | drivers/dma/ioat/dma_v2.c | 25 |
1 files changed, 11 insertions, 14 deletions
diff --git a/drivers/dma/ioat/dma_v2.c b/drivers/dma/ioat/dma_v2.c index 58881860f400..ca1134249341 100644 --- a/drivers/dma/ioat/dma_v2.c +++ b/drivers/dma/ioat/dma_v2.c @@ -200,8 +200,7 @@ static void ioat2_reset_channel(struct ioat2_dma_chan *ioat) return; chanerr = readl(chan->reg_base + IOAT_CHANERR_OFFSET); - chansts = (chan->completion_virt->low - & IOAT_CHANSTS_DMA_TRANSFER_STATUS); + chansts = *chan->completion & IOAT_CHANSTS_DMA_TRANSFER_STATUS; if (chanerr) { dev_err(to_dev(chan), "chan%d, CHANSTS = 0x%08x CHANERR = 0x%04x, clearing\n", @@ -281,7 +280,7 @@ static void ioat2_cleanup(struct ioat2_dma_chan *ioat) int i; struct dma_async_tx_descriptor *tx; - prefetch(chan->completion_virt); + prefetch(chan->completion); spin_lock_bh(&chan->cleanup_lock); phys_complete = ioat_get_current_completion(chan); @@ -470,17 +469,15 @@ static int ioat2_alloc_chan_resources(struct dma_chan *c) /* allocate a completion writeback area */ /* doing 2 32bit writes to mmio since 1 64b write doesn't work */ - chan->completion_virt = pci_pool_alloc(chan->device->completion_pool, - GFP_KERNEL, - &chan->completion_addr); - if (!chan->completion_virt) + chan->completion = pci_pool_alloc(chan->device->completion_pool, + GFP_KERNEL, &chan->completion_dma); + if (!chan->completion) return -ENOMEM; - memset(chan->completion_virt, 0, - sizeof(*chan->completion_virt)); - writel(((u64) chan->completion_addr) & 0x00000000FFFFFFFF, + memset(chan->completion, 0, sizeof(*chan->completion)); + writel(((u64) chan->completion_dma) & 0x00000000FFFFFFFF, chan->reg_base + IOAT_CHANCMP_OFFSET_LOW); - writel(((u64) chan->completion_addr) >> 32, + writel(((u64) chan->completion_dma) >> 32, chan->reg_base + IOAT_CHANCMP_OFFSET_HIGH); ioat->alloc_order = ioat_get_alloc_order(); @@ -655,12 +652,12 @@ static void ioat2_free_chan_resources(struct dma_chan *c) ioat->ring = NULL; ioat->alloc_order = 0; pci_pool_free(ioatdma_device->completion_pool, - chan->completion_virt, - chan->completion_addr); + chan->completion, + chan->completion_dma); spin_unlock_bh(&ioat->ring_lock); chan->last_completion = 0; - chan->completion_addr = 0; + chan->completion_dma = 0; ioat->pending = 0; ioat->dmacount = 0; chan->watchdog_completion = 0; |