diff options
| -rw-r--r-- | drivers/dma/coh901318.c | 42 |
1 files changed, 28 insertions, 14 deletions
diff --git a/drivers/dma/coh901318.c b/drivers/dma/coh901318.c index 64a937262a4..f1bf4f74ad8 100644 --- a/drivers/dma/coh901318.c +++ b/drivers/dma/coh901318.c @@ -80,18 +80,16 @@ struct coh901318_chan { static void coh901318_list_print(struct coh901318_chan *cohc, struct coh901318_lli *lli) { - struct coh901318_lli *l; - dma_addr_t addr = virt_to_phys(lli); + struct coh901318_lli *l = lli; int i = 0; - while (addr) { - l = phys_to_virt(addr); + while (l) { dev_vdbg(COHC_2_DEV(cohc), "i %d, lli %p, ctrl 0x%x, src 0x%x" - ", dst 0x%x, link 0x%x link_virt 0x%p\n", + ", dst 0x%x, link 0x%x virt_link_addr 0x%p\n", i, l, l->control, l->src_addr, l->dst_addr, - l->link_addr, phys_to_virt(l->link_addr)); + l->link_addr, l->virt_link_addr); i++; - addr = l->link_addr; + l = l->virt_link_addr; } } @@ -125,7 +123,7 @@ static int coh901318_debugfs_read(struct file *file, char __user *buf, goto err_kmalloc; tmp = dev_buf; - tmp += sprintf(tmp, "DMA -- enable dma channels\n"); + tmp += sprintf(tmp, "DMA -- enabled dma channels\n"); for (i = 0; i < debugfs_dma_base->platform->max_channels; i++) if (started_channels & (1 << i)) @@ -592,6 +590,10 @@ static struct coh901318_desc *coh901318_queue_start(struct coh901318_chan *cohc) return cohd_que; } +/* + * This tasklet is called from the interrupt handler to + * handle each descriptor (DMA job) that is sent to a channel. + */ static void dma_tasklet(unsigned long data) { struct coh901318_chan *cohc = (struct coh901318_chan *) data; @@ -600,9 +602,13 @@ static void dma_tasklet(unsigned long data) dma_async_tx_callback callback; void *callback_param; + dev_vdbg(COHC_2_DEV(cohc), "[%s] chan_id %d" + " nbr_active_done %ld\n", __func__, + cohc->id, cohc->nbr_active_done); + spin_lock_irqsave(&cohc->lock, flags); - /* get first active entry from list */ + /* get first active descriptor entry from list */ cohd_fin = coh901318_first_active_get(cohc); BUG_ON(cohd_fin->pending_irqs == 0); @@ -636,10 +642,19 @@ static void dma_tasklet(unsigned long data) coh901318_desc_free(cohc, cohd_fin); } + /* + * If another interrupt fired while the tasklet was scheduling, + * we don't get called twice, so we have this number of active + * counter that keep track of the number of IRQs expected to + * be handled for this channel. If there happen to be more than + * one IRQ to be ack:ed, we simply schedule this tasklet again. + */ if (cohc->nbr_active_done) cohc->nbr_active_done--; if (cohc->nbr_active_done) { + dev_dbg(COHC_2_DEV(cohc), "scheduling tasklet again, new IRQs " + "came in while we were scheduling this tasklet\n"); if (cohc_chan_conf(cohc)->priority_high) tasklet_hi_schedule(&cohc->tasklet); else @@ -994,6 +1009,7 @@ coh901318_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, len += factor; } + pr_debug("Allocate %d lli:s for this transfer\n", len); data = coh901318_lli_alloc(&cohc->base->pool, len); if (data == NULL) @@ -1092,9 +1108,8 @@ coh901318_terminate_all(struct dma_chan *chan) /* release the lli allocation*/ coh901318_lli_free(&cohc->base->pool, &cohd->data); - coh901318_desc_remove(cohd); - /* return desc to free-list */ + coh901318_desc_remove(cohd); coh901318_desc_free(cohc, cohd); } @@ -1102,9 +1117,8 @@ coh901318_terminate_all(struct dma_chan *chan) /* release the lli allocation*/ coh901318_lli_free(&cohc->base->pool, &cohd->data); - coh901318_desc_remove(cohd); - /* return desc to free-list */ + coh901318_desc_remove(cohd); coh901318_desc_free(cohc, cohd); } @@ -1259,7 +1273,7 @@ static int __init coh901318_probe(struct platform_device *pdev) if (err) goto err_register_memcpy; - dev_dbg(&pdev->dev, "Initialized COH901318 DMA on virtual base 0x%08x\n", + dev_info(&pdev->dev, "Initialized COH901318 DMA on virtual base 0x%08x\n", (u32) base->virtbase); return err; |