[PATCH V2 03/12] DMA: PL330: Add DMA capabilities
Chanho Park
parkch98 at gmail.com
Fri Jul 15 00:45:44 EDT 2011
Hello,
2011/7/13 Kukjin Kim <kgene.kim at samsung.com>:
> From: Boojin Kim <boojin.kim at samsung.com>
>
> This patch adds DMA_CYCLIC capability that is used for audio driver
> and SLAVE_CONFIG capability for transmit between device and memory.
>
> Signed-off-by: Boojin Kim <boojin.kim at samsung.com>
> Cc: Vinod Koul <vinod.koul at intel.com>
> Cc: Dan Williams <dan.j.williams at intel.com>
> Signed-off-by: Kukjin Kim <kgene.kim at samsung.com>
> ---
> drivers/dma/pl330.c | 187 +++++++++++++++++++++++++++++++++++++++++++++++----
> 1 files changed, 173 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
> index 9bdda7b..2162ac5 100644
> --- a/drivers/dma/pl330.c
> +++ b/drivers/dma/pl330.c
> @@ -69,6 +69,9 @@ struct dma_pl330_chan {
> * NULL if the channel is available to be acquired.
> */
> void *pl330_chid;
> +
> + /* taks for cyclic capability */
> + struct tasklet_struct *cyclic_task;
> };
>
> struct dma_pl330_dmac {
> @@ -105,6 +108,7 @@ struct dma_pl330_desc {
>
> /* The channel which currently holds this desc */
> struct dma_pl330_chan *pchan;
> + bool cyclic;
> };
>
> static inline struct dma_pl330_chan *
> @@ -184,6 +188,60 @@ static inline void fill_queue(struct dma_pl330_chan *pch)
> }
> }
>
> +static void pl330_tasklet_cyclic(unsigned long data)
> +{
> + struct dma_pl330_chan *pch = (struct dma_pl330_chan *)data;
> + struct dma_pl330_desc *desc, *_dt;
> + unsigned long flags;
> + LIST_HEAD(list);
> +
> + spin_lock_irqsave(&pch->lock, flags);
> +
> + /* Pick up ripe tomatoes */
> + list_for_each_entry_safe(desc, _dt, &pch->work_list, node)
> + if ((desc->status == DONE) && desc->cyclic) {
> + dma_async_tx_callback callback;
> +
> + list_move_tail(&desc->node, &pch->work_list);
> + pch->completed = desc->txd.cookie;
> +
> + desc->status = PREP;
> +
> + /* Try to submit a req imm.
> + next to the last completed cookie */
> + fill_queue(pch);
> +
> + /* Make sure the PL330 Channel thread is active */
> + pl330_chan_ctrl(pch->pl330_chid, PL330_OP_START);
> +
> + callback = desc->txd.callback;
> + if (callback)
> + callback(desc->txd.callback_param);
> +
> + }
> +
> + spin_unlock_irqrestore(&pch->lock, flags);
> +}
> +
> +static void pl330_cyclic_free(struct dma_pl330_chan *pch)
> +{
> + struct dma_pl330_dmac *pdmac = pch->dmac;
> + struct dma_pl330_desc *desc, *_dt;
> + unsigned long flags;
> + LIST_HEAD(list);
> +
> + spin_lock_irqsave(&pdmac->pool_lock, flags);
> +
> + list_for_each_entry_safe(desc, _dt, &pch->work_list, node)
> + if (desc->cyclic)
> + list_move_tail(&desc->node, &list);
nitpick: indentation will be required after for_each
> +
> + list_splice_tail_init(&list, &pdmac->desc_pool);
> +
> + spin_unlock_irqrestore(&pdmac->pool_lock, flags);
> + pch->cyclic_task = NULL;
> +}
> +
> static void pl330_tasklet(unsigned long data)
> {
> struct dma_pl330_chan *pch = (struct dma_pl330_chan *)data;
> @@ -227,6 +285,9 @@ static void dma_pl330_rqcb(void *token, enum pl330_op_err err)
>
> spin_unlock_irqrestore(&pch->lock, flags);
>
> + if (pch->cyclic_task)
> + tasklet_schedule(pch->cyclic_task);
> + else
> tasklet_schedule(&pch->task);
> }
>
> @@ -256,25 +317,58 @@ static int pl330_alloc_chan_resources(struct dma_chan *chan)
> static int pl330_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, unsigned long arg)
> {
> struct dma_pl330_chan *pch = to_pchan(chan);
> - struct dma_pl330_desc *desc;
> + struct dma_pl330_desc *desc, *_dt;
> unsigned long flags;
> + struct dma_pl330_dmac *pdmac = pch->dmac;
> + struct dma_slave_config *slave_config;
> + struct dma_pl330_peri *peri;
> + int i;
> + LIST_HEAD(list);
>
> - /* Only supports DMA_TERMINATE_ALL */
> - if (cmd != DMA_TERMINATE_ALL)
> - return -ENXIO;
> -
> - spin_lock_irqsave(&pch->lock, flags);
> -
> - /* FLUSH the PL330 Channel thread */
> - pl330_chan_ctrl(pch->pl330_chid, PL330_OP_FLUSH);
> + switch (cmd) {
> + case DMA_TERMINATE_ALL:
> + spin_lock_irqsave(&pch->lock, flags);
>
> - /* Mark all desc done */
> - list_for_each_entry(desc, &pch->work_list, node)
> - desc->status = DONE;
> + /* FLUSH the PL330 Channel thread */
> + pl330_chan_ctrl(pch->pl330_chid, PL330_OP_FLUSH);
>
> - spin_unlock_irqrestore(&pch->lock, flags);
> + /* Mark all desc done */
> + list_for_each_entry_safe(desc, _dt, &pch->work_list , node) {
> + desc->status = DONE;
> + pch->completed = desc->txd.cookie;
> + list_move_tail(&desc->node, &list);
> + }
>
> - pl330_tasklet((unsigned long) pch);
> + list_splice_tail_init(&list, &pdmac->desc_pool);
> + spin_unlock_irqrestore(&pch->lock, flags);
> + break;
> + case DMA_SLAVE_CONFIG:
> + slave_config = (struct dma_slave_config *)arg;
> + peri = pch->chan.private;
> +
> + if (slave_config->direction == DMA_TO_DEVICE) {
> + if (slave_config->dst_addr)
> + peri->fifo_addr = slave_config->dst_addr;
> + if (slave_config->dst_addr_width) {
> + i = 0;
> + while (slave_config->dst_addr_width != (1 << i))
> + i++;
> + peri->burst_sz = i;
> + }
> + } else if (slave_config->direction == DMA_FROM_DEVICE) {
> + if (slave_config->src_addr)
> + peri->fifo_addr = slave_config->src_addr;
> + if (slave_config->src_addr_width) {
> + i = 0;
> + while (slave_config->src_addr_width != (1 << i))
> + i++;
> + peri->burst_sz = i;
> + }
> + }
> + break;
> + default:
> + return -ENXIO;
To print error message in the default case will be better.
> + }
>
> return 0;
> }
> @@ -291,6 +385,9 @@ static void pl330_free_chan_resources(struct dma_chan *chan)
> pl330_release_channel(pch->pl330_chid);
> pch->pl330_chid = NULL;
>
> + if (pch->cyclic_task)
> + pl330_cyclic_free(pch);
> +
> spin_unlock_irqrestore(&pch->lock, flags);
> }
>
> @@ -522,6 +619,66 @@ 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);
> + struct dma_pl330_peri *peri = chan->private;
> + dma_addr_t dst;
> + dma_addr_t src;
> +
> + pch = to_pchan(chan);
> + if (!pch) {
> + dev_err(pch->dmac->pif.dev, "%s:%d Unable to fetch desc\n",
> + __func__, __LINE__);
> + return NULL;
> + }
'pch' is already acquired when defined. It's duplicated.
dev_err has a incorrect parameter because pch is NULL.
Accessing pch->dmac will be failed.
> +
> + 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 = peri->fifo_addr;
> + break;
> + case DMA_FROM_DEVICE:
> + desc->rqcfg.src_inc = 0;
> + desc->rqcfg.dst_inc = 1;
> + src = peri->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 = peri->burst_sz;
> + desc->rqcfg.brst_len = 1;
> +
> + if (!pch->cyclic_task) {
> + pch->cyclic_task =
> + kmalloc(sizeof(struct tasklet_struct), GFP_KERNEL);
> + tasklet_init(pch->cyclic_task,
> + pl330_tasklet_cyclic, (unsigned int)pch);
> + }
> +
> + desc->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)
> @@ -756,6 +913,7 @@ 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");
> @@ -781,6 +939,7 @@ 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;
> --
> 1.7.1
>
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--
Best Regards,
Chanho Park
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