diff options
Diffstat (limited to 'drivers/dma/xilinx')
-rw-r--r-- | drivers/dma/xilinx/xilinx_vdma.c | 206 |
1 files changed, 110 insertions, 96 deletions
diff --git a/drivers/dma/xilinx/xilinx_vdma.c b/drivers/dma/xilinx/xilinx_vdma.c index 6f4b5017c..ef67f278e 100644 --- a/drivers/dma/xilinx/xilinx_vdma.c +++ b/drivers/dma/xilinx/xilinx_vdma.c @@ -28,6 +28,7 @@ #include <linux/init.h> #include <linux/interrupt.h> #include <linux/io.h> +#include <linux/iopoll.h> #include <linux/module.h> #include <linux/of_address.h> #include <linux/of_dma.h> @@ -190,8 +191,7 @@ struct xilinx_vdma_tx_descriptor { * @desc_offset: TX descriptor registers offset * @lock: Descriptor operation lock * @pending_list: Descriptors waiting - * @active_desc: Active descriptor - * @allocated_desc: Allocated descriptor + * @active_list: Descriptors ready to submit * @done_list: Complete descriptors * @common: DMA common channel * @desc_pool: Descriptors pool @@ -206,6 +206,7 @@ struct xilinx_vdma_tx_descriptor { * @tasklet: Cleanup work after irq * @config: Device configuration info * @flush_on_fsync: Flush on Frame sync + * @desc_pendingcount: Descriptor pending count */ struct xilinx_vdma_chan { struct xilinx_vdma_device *xdev; @@ -213,8 +214,7 @@ struct xilinx_vdma_chan { u32 desc_offset; spinlock_t lock; struct list_head pending_list; - struct xilinx_vdma_tx_descriptor *active_desc; - struct xilinx_vdma_tx_descriptor *allocated_desc; + struct list_head active_list; struct list_head done_list; struct dma_chan common; struct dma_pool *desc_pool; @@ -229,6 +229,7 @@ struct xilinx_vdma_chan { struct tasklet_struct tasklet; struct xilinx_vdma_config config; bool flush_on_fsync; + u32 desc_pendingcount; }; /** @@ -254,6 +255,9 @@ struct xilinx_vdma_device { container_of(chan, struct xilinx_vdma_chan, common) #define to_vdma_tx_descriptor(tx) \ container_of(tx, struct xilinx_vdma_tx_descriptor, async_tx) +#define xilinx_vdma_poll_timeout(chan, reg, val, cond, delay_us, timeout_us) \ + readl_poll_timeout(chan->xdev->regs + chan->ctrl_offset + reg, val, \ + cond, delay_us, timeout_us) /* IO accessors */ static inline u32 vdma_read(struct xilinx_vdma_chan *chan, u32 reg) @@ -342,19 +346,11 @@ static struct xilinx_vdma_tx_descriptor * xilinx_vdma_alloc_tx_descriptor(struct xilinx_vdma_chan *chan) { struct xilinx_vdma_tx_descriptor *desc; - unsigned long flags; - - if (chan->allocated_desc) - return chan->allocated_desc; desc = kzalloc(sizeof(*desc), GFP_KERNEL); if (!desc) return NULL; - spin_lock_irqsave(&chan->lock, flags); - chan->allocated_desc = desc; - spin_unlock_irqrestore(&chan->lock, flags); - INIT_LIST_HEAD(&desc->segments); return desc; @@ -412,9 +408,7 @@ static void xilinx_vdma_free_descriptors(struct xilinx_vdma_chan *chan) xilinx_vdma_free_desc_list(chan, &chan->pending_list); xilinx_vdma_free_desc_list(chan, &chan->done_list); - - xilinx_vdma_free_tx_descriptor(chan, chan->active_desc); - chan->active_desc = NULL; + xilinx_vdma_free_desc_list(chan, &chan->active_list); spin_unlock_irqrestore(&chan->lock, flags); } @@ -560,18 +554,17 @@ static bool xilinx_vdma_is_idle(struct xilinx_vdma_chan *chan) */ static void xilinx_vdma_halt(struct xilinx_vdma_chan *chan) { - int loop = XILINX_VDMA_LOOP_COUNT; + int err; + u32 val; vdma_ctrl_clr(chan, XILINX_VDMA_REG_DMACR, XILINX_VDMA_DMACR_RUNSTOP); /* Wait for the hardware to halt */ - do { - if (vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR) & - XILINX_VDMA_DMASR_HALTED) - break; - } while (loop--); + err = xilinx_vdma_poll_timeout(chan, XILINX_VDMA_REG_DMASR, val, + (val & XILINX_VDMA_DMASR_HALTED), 0, + XILINX_VDMA_LOOP_COUNT); - if (!loop) { + if (err) { dev_err(chan->dev, "Cannot stop channel %p: %x\n", chan, vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR)); chan->err = true; @@ -586,18 +579,17 @@ static void xilinx_vdma_halt(struct xilinx_vdma_chan *chan) */ static void xilinx_vdma_start(struct xilinx_vdma_chan *chan) { - int loop = XILINX_VDMA_LOOP_COUNT; + int err; + u32 val; vdma_ctrl_set(chan, XILINX_VDMA_REG_DMACR, XILINX_VDMA_DMACR_RUNSTOP); /* Wait for the hardware to start */ - do { - if (!(vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR) & - XILINX_VDMA_DMASR_HALTED)) - break; - } while (loop--); + err = xilinx_vdma_poll_timeout(chan, XILINX_VDMA_REG_DMASR, val, + !(val & XILINX_VDMA_DMASR_HALTED), 0, + XILINX_VDMA_LOOP_COUNT); - if (!loop) { + if (err) { dev_err(chan->dev, "Cannot start channel %p: %x\n", chan, vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR)); @@ -614,45 +606,39 @@ static void xilinx_vdma_start(struct xilinx_vdma_chan *chan) static void xilinx_vdma_start_transfer(struct xilinx_vdma_chan *chan) { struct xilinx_vdma_config *config = &chan->config; - struct xilinx_vdma_tx_descriptor *desc; - unsigned long flags; + struct xilinx_vdma_tx_descriptor *desc, *tail_desc; u32 reg; - struct xilinx_vdma_tx_segment *head, *tail = NULL; + struct xilinx_vdma_tx_segment *tail_segment; + /* This function was invoked with lock held */ if (chan->err) return; - spin_lock_irqsave(&chan->lock, flags); - - /* There's already an active descriptor, bail out. */ - if (chan->active_desc) - goto out_unlock; - if (list_empty(&chan->pending_list)) - goto out_unlock; + return; desc = list_first_entry(&chan->pending_list, struct xilinx_vdma_tx_descriptor, node); + tail_desc = list_last_entry(&chan->pending_list, + struct xilinx_vdma_tx_descriptor, node); + + 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_vdma_is_running(chan) && !xilinx_vdma_is_idle(chan)) { dev_dbg(chan->dev, "DMA controller still busy\n"); - goto out_unlock; + return; } /* * If hardware is idle, then all descriptors on the running lists are * done, start new transfers */ - if (chan->has_sg) { - head = list_first_entry(&desc->segments, - struct xilinx_vdma_tx_segment, node); - tail = list_entry(desc->segments.prev, - struct xilinx_vdma_tx_segment, node); - - vdma_ctrl_write(chan, XILINX_VDMA_REG_CURDESC, head->phys); - } + if (chan->has_sg) + vdma_ctrl_write(chan, XILINX_VDMA_REG_CURDESC, + desc->async_tx.phys); /* Configure the hardware using info in the config structure */ reg = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR); @@ -662,6 +648,10 @@ static void xilinx_vdma_start_transfer(struct xilinx_vdma_chan *chan) else reg &= ~XILINX_VDMA_DMACR_FRAMECNT_EN; + /* Configure channel to allow number frame buffers */ + vdma_ctrl_write(chan, XILINX_VDMA_REG_FRMSTORE, + chan->desc_pendingcount); + /* * With SG, start with circular mode, so that BDs can be fetched. * In direct register mode, if not parking, enable circular mode @@ -690,16 +680,19 @@ static void xilinx_vdma_start_transfer(struct xilinx_vdma_chan *chan) xilinx_vdma_start(chan); if (chan->err) - goto out_unlock; + return; /* Start the transfer */ if (chan->has_sg) { - vdma_ctrl_write(chan, XILINX_VDMA_REG_TAILDESC, tail->phys); + vdma_ctrl_write(chan, XILINX_VDMA_REG_TAILDESC, + tail_segment->phys); } else { struct xilinx_vdma_tx_segment *segment, *last = NULL; int i = 0; - list_for_each_entry(segment, &desc->segments, node) { + list_for_each_entry(desc, &chan->pending_list, node) { + segment = list_first_entry(&desc->segments, + struct xilinx_vdma_tx_segment, node); vdma_desc_write(chan, XILINX_VDMA_REG_START_ADDRESS(i++), segment->hw.buf_addr); @@ -707,7 +700,7 @@ static void xilinx_vdma_start_transfer(struct xilinx_vdma_chan *chan) } if (!last) - goto out_unlock; + return; /* HW expects these parameters to be same for one transaction */ vdma_desc_write(chan, XILINX_VDMA_REG_HSIZE, last->hw.hsize); @@ -716,11 +709,8 @@ static void xilinx_vdma_start_transfer(struct xilinx_vdma_chan *chan) vdma_desc_write(chan, XILINX_VDMA_REG_VSIZE, last->hw.vsize); } - list_del(&desc->node); - chan->active_desc = desc; - -out_unlock: - spin_unlock_irqrestore(&chan->lock, flags); + list_splice_tail_init(&chan->pending_list, &chan->active_list); + chan->desc_pendingcount = 0; } /** @@ -730,8 +720,11 @@ out_unlock: static void xilinx_vdma_issue_pending(struct dma_chan *dchan) { struct xilinx_vdma_chan *chan = to_xilinx_chan(dchan); + unsigned long flags; + spin_lock_irqsave(&chan->lock, flags); xilinx_vdma_start_transfer(chan); + spin_unlock_irqrestore(&chan->lock, flags); } /** @@ -742,24 +735,17 @@ static void xilinx_vdma_issue_pending(struct dma_chan *dchan) */ static void xilinx_vdma_complete_descriptor(struct xilinx_vdma_chan *chan) { - struct xilinx_vdma_tx_descriptor *desc; - unsigned long flags; + struct xilinx_vdma_tx_descriptor *desc, *next; - spin_lock_irqsave(&chan->lock, flags); + /* This function was invoked with lock held */ + if (list_empty(&chan->active_list)) + return; - desc = chan->active_desc; - if (!desc) { - dev_dbg(chan->dev, "no running descriptors\n"); - goto out_unlock; + list_for_each_entry_safe(desc, next, &chan->active_list, node) { + list_del(&desc->node); + dma_cookie_complete(&desc->async_tx); + list_add_tail(&desc->node, &chan->done_list); } - - dma_cookie_complete(&desc->async_tx); - list_add_tail(&desc->node, &chan->done_list); - - chan->active_desc = NULL; - -out_unlock: - spin_unlock_irqrestore(&chan->lock, flags); } /** @@ -770,21 +756,17 @@ out_unlock: */ static int xilinx_vdma_reset(struct xilinx_vdma_chan *chan) { - int loop = XILINX_VDMA_LOOP_COUNT; + int err; u32 tmp; vdma_ctrl_set(chan, XILINX_VDMA_REG_DMACR, XILINX_VDMA_DMACR_RESET); - tmp = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR) & - XILINX_VDMA_DMACR_RESET; - /* Wait for the hardware to finish reset */ - do { - tmp = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR) & - XILINX_VDMA_DMACR_RESET; - } while (loop-- && tmp); + err = xilinx_vdma_poll_timeout(chan, XILINX_VDMA_REG_DMACR, tmp, + !(tmp & XILINX_VDMA_DMACR_RESET), 0, + XILINX_VDMA_LOOP_COUNT); - if (!loop) { + if (err) { dev_err(chan->dev, "reset timeout, cr %x, sr %x\n", vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR), vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR)); @@ -793,7 +775,7 @@ static int xilinx_vdma_reset(struct xilinx_vdma_chan *chan) chan->err = false; - return 0; + return err; } /** @@ -870,8 +852,10 @@ static irqreturn_t xilinx_vdma_irq_handler(int irq, void *data) } if (status & XILINX_VDMA_DMASR_FRM_CNT_IRQ) { + spin_lock(&chan->lock); xilinx_vdma_complete_descriptor(chan); xilinx_vdma_start_transfer(chan); + spin_unlock(&chan->lock); } tasklet_schedule(&chan->tasklet); @@ -879,6 +863,44 @@ static irqreturn_t xilinx_vdma_irq_handler(int irq, void *data) } /** + * append_desc_queue - Queuing descriptor + * @chan: Driver specific dma channel + * @desc: dma transaction descriptor + */ +static void append_desc_queue(struct xilinx_vdma_chan *chan, + struct xilinx_vdma_tx_descriptor *desc) +{ + struct xilinx_vdma_tx_segment *tail_segment; + struct xilinx_vdma_tx_descriptor *tail_desc; + + if (list_empty(&chan->pending_list)) + goto append; + + /* + * Add the hardware descriptor to the chain of hardware descriptors + * that already exists in memory. + */ + tail_desc = list_last_entry(&chan->pending_list, + struct xilinx_vdma_tx_descriptor, node); + tail_segment = list_last_entry(&tail_desc->segments, + struct xilinx_vdma_tx_segment, node); + tail_segment->hw.next_desc = (u32)desc->async_tx.phys; + + /* + * Add the software descriptor and all children to the list + * of pending transactions + */ +append: + list_add_tail(&desc->node, &chan->pending_list); + chan->desc_pendingcount++; + + if (unlikely(chan->desc_pendingcount > chan->num_frms)) { + dev_dbg(chan->dev, "desc pendingcount is too high\n"); + chan->desc_pendingcount = chan->num_frms; + } +} + +/** * xilinx_vdma_tx_submit - Submit DMA transaction * @tx: Async transaction descriptor * @@ -906,11 +928,8 @@ static dma_cookie_t xilinx_vdma_tx_submit(struct dma_async_tx_descriptor *tx) cookie = dma_cookie_assign(tx); - /* Append the transaction to the pending transactions queue. */ - list_add_tail(&desc->node, &chan->pending_list); - - /* Free the allocated desc */ - chan->allocated_desc = NULL; + /* Put this transaction onto the tail of the pending queue */ + append_desc_queue(chan, desc); spin_unlock_irqrestore(&chan->lock, flags); @@ -973,13 +992,6 @@ xilinx_vdma_dma_prep_interleaved(struct dma_chan *dchan, else hw->buf_addr = xt->src_start; - /* Link the previous next descriptor to current */ - if (!list_empty(&desc->segments)) { - prev = list_last_entry(&desc->segments, - struct xilinx_vdma_tx_segment, node); - prev->hw.next_desc = segment->phys; - } - /* Insert the segment into the descriptor segments list. */ list_add_tail(&segment->node, &desc->segments); @@ -988,7 +1000,7 @@ xilinx_vdma_dma_prep_interleaved(struct dma_chan *dchan, /* Link the last hardware descriptor with the first. */ segment = list_first_entry(&desc->segments, struct xilinx_vdma_tx_segment, node); - prev->hw.next_desc = segment->phys; + desc->async_tx.phys = segment->phys; return &desc->async_tx; @@ -1127,10 +1139,12 @@ static int xilinx_vdma_chan_probe(struct xilinx_vdma_device *xdev, chan->dev = xdev->dev; chan->xdev = xdev; chan->has_sg = xdev->has_sg; + chan->desc_pendingcount = 0x0; spin_lock_init(&chan->lock); INIT_LIST_HEAD(&chan->pending_list); INIT_LIST_HEAD(&chan->done_list); + INIT_LIST_HEAD(&chan->active_list); /* Retrieve the channel properties from the device tree */ has_dre = of_property_read_bool(node, "xlnx,include-dre"); @@ -1222,7 +1236,7 @@ static struct dma_chan *of_dma_xilinx_xlate(struct of_phandle_args *dma_spec, struct xilinx_vdma_device *xdev = ofdma->of_dma_data; int chan_id = dma_spec->args[0]; - if (chan_id >= XILINX_VDMA_MAX_CHANS_PER_DEVICE) + if (chan_id >= XILINX_VDMA_MAX_CHANS_PER_DEVICE || !xdev->chan[chan_id]) return NULL; return dma_get_slave_channel(&xdev->chan[chan_id]->common); |