From: Boojin Kim Date: Fri, 2 Sep 2011 00:44:33 +0000 (+0900) Subject: DMA: PL330: Add DMA_CYCLIC capability X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=42bc9cf45939c26a5c5eb946d4fd35f1a7b0f9f8;p=linux-beck.git DMA: PL330: Add DMA_CYCLIC capability This patch adds DMA_CYCLIC capability that is used for audio driver. DMA driver activated with it reuses the dma requests that were submitted through tx_submit(). Signed-off-by: Boojin Kim Acked-by: Linus Walleij Acked-by: Vinod Koul Cc: Dan Williams Signed-off-by: Kukjin Kim Signed-off-by: Vinod Koul --- diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c index 59943ec1e74a..621134fdba4c 100644 --- a/drivers/dma/pl330.c +++ b/drivers/dma/pl330.c @@ -75,6 +75,9 @@ struct dma_pl330_chan { int burst_sz; /* the peripheral fifo width */ int burst_len; /* the number of burst */ dma_addr_t fifo_addr; + + /* for cyclic capability */ + bool cyclic; }; struct dma_pl330_dmac { @@ -161,6 +164,31 @@ static inline void free_desc_list(struct list_head *list) spin_unlock_irqrestore(&pdmac->pool_lock, flags); } +static inline void handle_cyclic_desc_list(struct list_head *list) +{ + struct dma_pl330_desc *desc; + struct dma_pl330_chan *pch; + unsigned long flags; + + if (list_empty(list)) + return; + + list_for_each_entry(desc, list, node) { + dma_async_tx_callback callback; + + /* Change status to reload it */ + desc->status = PREP; + pch = desc->pchan; + callback = desc->txd.callback; + if (callback) + callback(desc->txd.callback_param); + } + + spin_lock_irqsave(&pch->lock, flags); + list_splice_tail_init(list, &pch->work_list); + spin_unlock_irqrestore(&pch->lock, flags); +} + static inline void fill_queue(struct dma_pl330_chan *pch) { struct dma_pl330_desc *desc; @@ -214,7 +242,10 @@ static void pl330_tasklet(unsigned long data) spin_unlock_irqrestore(&pch->lock, flags); - free_desc_list(&list); + if (pch->cyclic) + handle_cyclic_desc_list(&list); + else + free_desc_list(&list); } static void dma_pl330_rqcb(void *token, enum pl330_op_err err) @@ -245,6 +276,7 @@ static int pl330_alloc_chan_resources(struct dma_chan *chan) spin_lock_irqsave(&pch->lock, flags); pch->completed = chan->cookie = 1; + pch->cyclic = false; pch->pl330_chid = pl330_request_channel(&pdmac->pif); if (!pch->pl330_chid) { @@ -324,6 +356,9 @@ static void pl330_free_chan_resources(struct dma_chan *chan) pl330_release_channel(pch->pl330_chid); pch->pl330_chid = NULL; + if (pch->cyclic) + list_splice_tail_init(&pch->work_list, &pch->dmac->desc_pool); + spin_unlock_irqrestore(&pch->lock, flags); } @@ -560,6 +595,51 @@ static inline int get_burst_len(struct dma_pl330_desc *desc, size_t len) return burst_len; } +static struct dma_async_tx_descriptor *pl330_prep_dma_cyclic( + struct dma_chan *chan, dma_addr_t dma_addr, size_t len, + size_t period_len, enum dma_data_direction direction) +{ + struct dma_pl330_desc *desc; + struct dma_pl330_chan *pch = to_pchan(chan); + dma_addr_t dst; + dma_addr_t src; + + desc = pl330_get_desc(pch); + if (!desc) { + dev_err(pch->dmac->pif.dev, "%s:%d Unable to fetch desc\n", + __func__, __LINE__); + return NULL; + } + + switch (direction) { + case DMA_TO_DEVICE: + desc->rqcfg.src_inc = 1; + desc->rqcfg.dst_inc = 0; + src = dma_addr; + dst = pch->fifo_addr; + break; + case DMA_FROM_DEVICE: + desc->rqcfg.src_inc = 0; + desc->rqcfg.dst_inc = 1; + src = pch->fifo_addr; + dst = dma_addr; + break; + default: + dev_err(pch->dmac->pif.dev, "%s:%d Invalid dma direction\n", + __func__, __LINE__); + return NULL; + } + + desc->rqcfg.brst_size = pch->burst_sz; + desc->rqcfg.brst_len = 1; + + pch->cyclic = true; + + fill_px(&desc->px, dst, src, period_len); + + return &desc->txd; +} + static struct dma_async_tx_descriptor * pl330_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dst, dma_addr_t src, size_t len, unsigned long flags) @@ -791,6 +871,7 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id) case MEMTODEV: case DEVTOMEM: dma_cap_set(DMA_SLAVE, pd->cap_mask); + dma_cap_set(DMA_CYCLIC, pd->cap_mask); break; default: dev_err(&adev->dev, "DEVTODEV Not Supported\n"); @@ -819,6 +900,7 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id) pd->device_alloc_chan_resources = pl330_alloc_chan_resources; pd->device_free_chan_resources = pl330_free_chan_resources; pd->device_prep_dma_memcpy = pl330_prep_dma_memcpy; + pd->device_prep_dma_cyclic = pl330_prep_dma_cyclic; pd->device_tx_status = pl330_tx_status; pd->device_prep_slave_sg = pl330_prep_slave_sg; pd->device_control = pl330_control;