diff options
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/xilinx/xilinx_dma.c | 60 |
1 files changed, 22 insertions, 38 deletions
diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c index 5eef13380ca8..c2465632f3f0 100644 --- a/drivers/dma/xilinx/xilinx_dma.c +++ b/drivers/dma/xilinx/xilinx_dma.c @@ -321,6 +321,7 @@ struct xilinx_dma_tx_descriptor { * @cyclic: Check for cyclic transfers. * @genlock: Support genlock mode * @err: Channel has errors + * @idle: Check for channel idle * @tasklet: Cleanup work after irq * @config: Device configuration info * @flush_on_fsync: Flush on Frame sync @@ -352,6 +353,7 @@ struct xilinx_dma_chan { bool cyclic; bool genlock; bool err; + bool idle; struct tasklet_struct tasklet; struct xilinx_vdma_config config; bool flush_on_fsync; @@ -936,32 +938,6 @@ static enum dma_status xilinx_dma_tx_status(struct dma_chan *dchan, } /** - * xilinx_dma_is_running - Check if DMA channel is running - * @chan: Driver specific DMA channel - * - * Return: '1' if running, '0' if not. - */ -static bool xilinx_dma_is_running(struct xilinx_dma_chan *chan) -{ - return !(dma_ctrl_read(chan, XILINX_DMA_REG_DMASR) & - XILINX_DMA_DMASR_HALTED) && - (dma_ctrl_read(chan, XILINX_DMA_REG_DMACR) & - XILINX_DMA_DMACR_RUNSTOP); -} - -/** - * xilinx_dma_is_idle - Check if DMA channel is idle - * @chan: Driver specific DMA channel - * - * Return: '1' if idle, '0' if not. - */ -static bool xilinx_dma_is_idle(struct xilinx_dma_chan *chan) -{ - return dma_ctrl_read(chan, XILINX_DMA_REG_DMASR) & - XILINX_DMA_DMASR_IDLE; -} - -/** * xilinx_dma_stop_transfer - Halt DMA channel * @chan: Driver specific DMA channel */ @@ -1029,6 +1005,9 @@ static void xilinx_vdma_start_transfer(struct xilinx_dma_chan *chan) if (chan->err) return; + if (!chan->idle) + return; + if (list_empty(&chan->pending_list)) return; @@ -1040,13 +1019,6 @@ static void xilinx_vdma_start_transfer(struct xilinx_dma_chan *chan) tail_segment = list_last_entry(&tail_desc->segments, struct xilinx_vdma_tx_segment, node); - /* If it is SG mode and hardware is busy, cannot submit */ - if (chan->has_sg && xilinx_dma_is_running(chan) && - !xilinx_dma_is_idle(chan)) { - dev_dbg(chan->dev, "DMA controller still busy\n"); - return; - } - /* * If hardware is idle, then all descriptors on the running lists are * done, start new transfers @@ -1143,6 +1115,8 @@ static void xilinx_vdma_start_transfer(struct xilinx_dma_chan *chan) list_splice_tail_init(&chan->pending_list, &chan->active_list); chan->desc_pendingcount = 0; } + + chan->idle = false; } /** @@ -1158,6 +1132,9 @@ static void xilinx_cdma_start_transfer(struct xilinx_dma_chan *chan) if (chan->err) return; + if (!chan->idle) + return; + if (list_empty(&chan->pending_list)) return; @@ -1203,6 +1180,7 @@ static void xilinx_cdma_start_transfer(struct xilinx_dma_chan *chan) list_splice_tail_init(&chan->pending_list, &chan->active_list); chan->desc_pendingcount = 0; + chan->idle = false; } /** @@ -1221,12 +1199,8 @@ static void xilinx_dma_start_transfer(struct xilinx_dma_chan *chan) if (list_empty(&chan->pending_list)) return; - /* If it is SG mode and hardware is busy, cannot submit */ - if (chan->has_sg && xilinx_dma_is_running(chan) && - !xilinx_dma_is_idle(chan)) { - dev_dbg(chan->dev, "DMA controller still busy\n"); + if (!chan->idle) return; - } head_desc = list_first_entry(&chan->pending_list, struct xilinx_dma_tx_descriptor, node); @@ -1324,6 +1298,7 @@ static void xilinx_dma_start_transfer(struct xilinx_dma_chan *chan) list_splice_tail_init(&chan->pending_list, &chan->active_list); chan->desc_pendingcount = 0; + chan->idle = false; } /** @@ -1388,6 +1363,7 @@ static int xilinx_dma_reset(struct xilinx_dma_chan *chan) } chan->err = false; + chan->idle = true; return err; } @@ -1469,6 +1445,7 @@ static irqreturn_t xilinx_dma_irq_handler(int irq, void *data) if (status & XILINX_DMA_DMASR_FRM_CNT_IRQ) { spin_lock(&chan->lock); xilinx_dma_complete_descriptor(chan); + chan->idle = true; chan->start_transfer(chan); spin_unlock(&chan->lock); } @@ -2029,6 +2006,7 @@ static int xilinx_dma_terminate_all(struct dma_chan *dchan) /* Remove and free all of the descriptors in the lists */ xilinx_dma_free_descriptors(chan); + chan->idle = true; if (chan->cyclic) { reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR); @@ -2344,6 +2322,12 @@ static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev, chan->has_sg = xdev->has_sg; chan->desc_pendingcount = 0x0; chan->ext_addr = xdev->ext_addr; + /* This variable enusres that descripotrs are not + * Submited when dma engine is in progress. This variable is + * Added to avoid pollling for a bit in the status register to + * Know dma state in the driver hot path. + */ + chan->idle = true; spin_lock_init(&chan->lock); INIT_LIST_HEAD(&chan->pending_list); |