From a575d0b4e663d818803f75de0cf4bc3c4b35b203 Mon Sep 17 00:00:00 2001 From: Nicholas Graumann Date: Tue, 15 Oct 2019 20:18:21 +0530 Subject: 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 Signed-off-by: Radhey Shyam Pandey Link: https://lore.kernel.org/r/1571150904-3988-5-git-send-email-radhey.shyam.pandey@xilinx.com Signed-off-by: Vinod Koul --- drivers/dma/xilinx/xilinx_dma.c | 71 +++++++++++++++++++++++++++++++---------- 1 file changed, 54 insertions(+), 17 deletions(-) (limited to 'drivers/dma') 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 @@ -784,6 +784,44 @@ 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 @@ -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; -- cgit v1.2.3