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authorNicholas Graumann <nick.graumann@gmail.com>2019-10-15 20:18:21 +0530
committerVinod Koul <vkoul@kernel.org>2019-10-20 19:35:27 +0530
commita575d0b4e663d818803f75de0cf4bc3c4b35b203 (patch)
treec125cdc8787ff7112c08924e508e367671b0dac0 /drivers/dma
parent95f68c62628085abff83a5add8db057fbf532f7f (diff)
downloadlinux-a575d0b4e663d818803f75de0cf4bc3c4b35b203.tar.bz2
dmaengine: xilinx_dma: Introduce xilinx_dma_get_residue
Introduce a function that can calculate residues for IPs that support it: AXI DMA and CDMA. Signed-off-by: Nicholas Graumann <nick.graumann@gmail.com> Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com> Link: https://lore.kernel.org/r/1571150904-3988-5-git-send-email-radhey.shyam.pandey@xilinx.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/dma')
-rw-r--r--drivers/dma/xilinx/xilinx_dma.c71
1 files changed, 54 insertions, 17 deletions
diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c
index 41d536c32957..fe265d942ed2 100644
--- a/drivers/dma/xilinx/xilinx_dma.c
+++ b/drivers/dma/xilinx/xilinx_dma.c
@@ -785,6 +785,44 @@ static void xilinx_dma_free_chan_resources(struct dma_chan *dchan)
}
/**
+ * xilinx_dma_get_residue - Compute residue for a given descriptor
+ * @chan: Driver specific dma channel
+ * @desc: dma transaction descriptor
+ *
+ * Return: The number of residue bytes for the descriptor.
+ */
+static u32 xilinx_dma_get_residue(struct xilinx_dma_chan *chan,
+ struct xilinx_dma_tx_descriptor *desc)
+{
+ struct xilinx_cdma_tx_segment *cdma_seg;
+ struct xilinx_axidma_tx_segment *axidma_seg;
+ struct xilinx_cdma_desc_hw *cdma_hw;
+ struct xilinx_axidma_desc_hw *axidma_hw;
+ struct list_head *entry;
+ u32 residue = 0;
+
+ list_for_each(entry, &desc->segments) {
+ if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
+ cdma_seg = list_entry(entry,
+ struct xilinx_cdma_tx_segment,
+ node);
+ cdma_hw = &cdma_seg->hw;
+ residue += (cdma_hw->control - cdma_hw->status) &
+ chan->xdev->max_buffer_len;
+ } else {
+ axidma_seg = list_entry(entry,
+ struct xilinx_axidma_tx_segment,
+ node);
+ axidma_hw = &axidma_seg->hw;
+ residue += (axidma_hw->control - axidma_hw->status) &
+ chan->xdev->max_buffer_len;
+ }
+ }
+
+ return residue;
+}
+
+/**
* xilinx_dma_chan_handle_cyclic - Cyclic dma callback
* @chan: Driver specific dma channel
* @desc: dma transaction descriptor
@@ -993,8 +1031,6 @@ static enum dma_status xilinx_dma_tx_status(struct dma_chan *dchan,
{
struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
struct xilinx_dma_tx_descriptor *desc;
- struct xilinx_axidma_tx_segment *segment;
- struct xilinx_axidma_desc_hw *hw;
enum dma_status ret;
unsigned long flags;
u32 residue = 0;
@@ -1003,22 +1039,20 @@ static enum dma_status xilinx_dma_tx_status(struct dma_chan *dchan,
if (ret == DMA_COMPLETE || !txstate)
return ret;
- if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
- spin_lock_irqsave(&chan->lock, flags);
+ spin_lock_irqsave(&chan->lock, flags);
- desc = list_last_entry(&chan->active_list,
- struct xilinx_dma_tx_descriptor, node);
- if (chan->has_sg) {
- list_for_each_entry(segment, &desc->segments, node) {
- hw = &segment->hw;
- residue += (hw->control - hw->status) &
- chan->xdev->max_buffer_len;
- }
- }
- spin_unlock_irqrestore(&chan->lock, flags);
+ desc = list_last_entry(&chan->active_list,
+ struct xilinx_dma_tx_descriptor, node);
+ /*
+ * VDMA and simple mode do not support residue reporting, so the
+ * residue field will always be 0.
+ */
+ if (chan->has_sg && chan->xdev->dma_config->dmatype != XDMA_TYPE_VDMA)
+ residue = xilinx_dma_get_residue(chan, desc);
- dma_set_residue(txstate, residue);
- }
+ spin_unlock_irqrestore(&chan->lock, flags);
+
+ dma_set_residue(txstate, residue);
return ret;
}
@@ -2705,12 +2739,15 @@ static int xilinx_dma_probe(struct platform_device *pdev)
xilinx_dma_prep_dma_cyclic;
xdev->common.device_prep_interleaved_dma =
xilinx_dma_prep_interleaved;
- /* Residue calculation is supported by only AXI DMA */
+ /* Residue calculation is supported by only AXI DMA and CDMA */
xdev->common.residue_granularity =
DMA_RESIDUE_GRANULARITY_SEGMENT;
} else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
dma_cap_set(DMA_MEMCPY, xdev->common.cap_mask);
xdev->common.device_prep_dma_memcpy = xilinx_cdma_prep_memcpy;
+ /* Residue calculation is supported by only AXI DMA and CDMA */
+ xdev->common.residue_granularity =
+ DMA_RESIDUE_GRANULARITY_SEGMENT;
} else {
xdev->common.device_prep_interleaved_dma =
xilinx_vdma_dma_prep_interleaved;