From 0c842b551063c5f7382ac9b457992f3b34972801 Mon Sep 17 00:00:00 2001 From: Rabin Vincent Date: Tue, 25 Jan 2011 11:18:35 +0100 Subject: dma40: cyclic xfer support Support cyclic transfers, which are useful for ALSA drivers. Acked-by: Per Forlin Acked-by: Jonas Aaberg Signed-off-by: Rabin Vincent Signed-off-by: Linus Walleij Signed-off-by: Dan Williams --- drivers/dma/ste_dma40.c | 172 +++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 140 insertions(+), 32 deletions(-) (limited to 'drivers/dma/ste_dma40.c') diff --git a/drivers/dma/ste_dma40.c b/drivers/dma/ste_dma40.c index 8fd0bb94e77..af955de035f 100644 --- a/drivers/dma/ste_dma40.c +++ b/drivers/dma/ste_dma40.c @@ -115,6 +115,7 @@ struct d40_desc { struct list_head node; bool is_in_client_list; + bool cyclic; }; /** @@ -527,17 +528,45 @@ static void d40_log_lli_to_lcxa(struct d40_chan *chan, struct d40_desc *desc) struct d40_log_lli_bidir *lli = &desc->lli_log; int lli_current = desc->lli_current; int lli_len = desc->lli_len; + bool cyclic = desc->cyclic; int curr_lcla = -EINVAL; + int first_lcla = 0; + bool linkback; - if (lli_len - lli_current > 1) + /* + * We may have partially running cyclic transfers, in case we did't get + * enough LCLA entries. + */ + linkback = cyclic && lli_current == 0; + + /* + * For linkback, we need one LCLA even with only one link, because we + * can't link back to the one in LCPA space + */ + if (linkback || (lli_len - lli_current > 1)) { curr_lcla = d40_lcla_alloc_one(chan, desc); + first_lcla = curr_lcla; + } + + /* + * For linkback, we normally load the LCPA in the loop since we need to + * link it to the second LCLA and not the first. However, if we + * couldn't even get a first LCLA, then we have to run in LCPA and + * reload manually. + */ + if (!linkback || curr_lcla == -EINVAL) { + unsigned int flags = 0; - d40_log_lli_lcpa_write(chan->lcpa, - &lli->dst[lli_current], - &lli->src[lli_current], - curr_lcla); + if (curr_lcla == -EINVAL) + flags |= LLI_TERM_INT; - lli_current++; + d40_log_lli_lcpa_write(chan->lcpa, + &lli->dst[lli_current], + &lli->src[lli_current], + curr_lcla, + flags); + lli_current++; + } if (curr_lcla < 0) goto out; @@ -546,17 +575,33 @@ static void d40_log_lli_to_lcxa(struct d40_chan *chan, struct d40_desc *desc) unsigned int lcla_offset = chan->phy_chan->num * 1024 + 8 * curr_lcla * 2; struct d40_log_lli *lcla = pool->base + lcla_offset; + unsigned int flags = 0; int next_lcla; if (lli_current + 1 < lli_len) next_lcla = d40_lcla_alloc_one(chan, desc); else - next_lcla = -EINVAL; + next_lcla = linkback ? first_lcla : -EINVAL; + + if (cyclic || next_lcla == -EINVAL) + flags |= LLI_TERM_INT; + if (linkback && curr_lcla == first_lcla) { + /* First link goes in both LCPA and LCLA */ + d40_log_lli_lcpa_write(chan->lcpa, + &lli->dst[lli_current], + &lli->src[lli_current], + next_lcla, flags); + } + + /* + * One unused LCLA in the cyclic case if the very first + * next_lcla fails... + */ d40_log_lli_lcla_write(lcla, &lli->dst[lli_current], &lli->src[lli_current], - next_lcla); + next_lcla, flags); dma_sync_single_range_for_device(chan->base->dev, pool->dma_addr, lcla_offset, @@ -565,7 +610,7 @@ static void d40_log_lli_to_lcxa(struct d40_chan *chan, struct d40_desc *desc) curr_lcla = next_lcla; - if (curr_lcla == -EINVAL) { + if (curr_lcla == -EINVAL || curr_lcla == first_lcla) { lli_current++; break; } @@ -1074,17 +1119,36 @@ static void dma_tc_handle(struct d40_chan *d40c) if (d40d == NULL) return; - d40_lcla_free_all(d40c, d40d); + if (d40d->cyclic) { + /* + * If this was a paritially loaded list, we need to reloaded + * it, and only when the list is completed. We need to check + * for done because the interrupt will hit for every link, and + * not just the last one. + */ + if (d40d->lli_current < d40d->lli_len + && !d40_tx_is_linked(d40c) + && !d40_residue(d40c)) { + d40_lcla_free_all(d40c, d40d); + d40_desc_load(d40c, d40d); + (void) d40_start(d40c); - if (d40d->lli_current < d40d->lli_len) { - d40_desc_load(d40c, d40d); - /* Start dma job */ - (void) d40_start(d40c); - return; - } + if (d40d->lli_current == d40d->lli_len) + d40d->lli_current = 0; + } + } else { + d40_lcla_free_all(d40c, d40d); - if (d40_queue_start(d40c) == NULL) - d40c->busy = false; + if (d40d->lli_current < d40d->lli_len) { + d40_desc_load(d40c, d40d); + /* Start dma job */ + (void) d40_start(d40c); + return; + } + + if (d40_queue_start(d40c) == NULL) + d40c->busy = false; + } d40c->pending_tx++; tasklet_schedule(&d40c->tasklet); @@ -1103,11 +1167,11 @@ static void dma_tasklet(unsigned long data) /* Get first active entry from list */ d40d = d40_first_active_get(d40c); - if (d40d == NULL) goto err; - d40c->completed = d40d->txd.cookie; + if (!d40d->cyclic) + d40c->completed = d40d->txd.cookie; /* * If terminating a channel pending_tx is set to zero. @@ -1122,16 +1186,18 @@ static void dma_tasklet(unsigned long data) callback = d40d->txd.callback; callback_param = d40d->txd.callback_param; - if (async_tx_test_ack(&d40d->txd)) { - d40_pool_lli_free(d40c, d40d); - d40_desc_remove(d40d); - d40_desc_free(d40c, d40d); - } else { - if (!d40d->is_in_client_list) { + if (!d40d->cyclic) { + if (async_tx_test_ack(&d40d->txd)) { + d40_pool_lli_free(d40c, d40d); d40_desc_remove(d40d); - d40_lcla_free_all(d40c, d40d); - list_add_tail(&d40d->node, &d40c->client); - d40d->is_in_client_list = true; + d40_desc_free(d40c, d40d); + } else { + if (!d40d->is_in_client_list) { + d40_desc_remove(d40d); + d40_lcla_free_all(d40c, d40d); + list_add_tail(&d40d->node, &d40c->client); + d40d->is_in_client_list = true; + } } } @@ -1694,19 +1760,23 @@ d40_prep_sg_phy(struct d40_chan *chan, struct d40_desc *desc, struct stedma40_chan_cfg *cfg = &chan->dma_cfg; struct stedma40_half_channel_info *src_info = &cfg->src_info; struct stedma40_half_channel_info *dst_info = &cfg->dst_info; + unsigned long flags = 0; int ret; + if (desc->cyclic) + flags |= LLI_CYCLIC | LLI_TERM_INT; + ret = d40_phy_sg_to_lli(sg_src, sg_len, src_dev_addr, desc->lli_phy.src, virt_to_phys(desc->lli_phy.src), chan->src_def_cfg, - src_info, dst_info); + src_info, dst_info, flags); ret = d40_phy_sg_to_lli(sg_dst, sg_len, dst_dev_addr, desc->lli_phy.dst, virt_to_phys(desc->lli_phy.dst), chan->dst_def_cfg, - dst_info, src_info); + dst_info, src_info, flags); dma_sync_single_for_device(chan->base->dev, desc->lli_pool.dma_addr, desc->lli_pool.size, DMA_TO_DEVICE); @@ -1789,12 +1859,16 @@ d40_prep_sg(struct dma_chan *dchan, struct scatterlist *sg_src, return NULL; } + spin_lock_irqsave(&chan->lock, flags); desc = d40_prep_desc(chan, sg_src, sg_len, dma_flags); if (desc == NULL) goto err; + if (sg_next(&sg_src[sg_len - 1]) == sg_src) + desc->cyclic = true; + if (direction != DMA_NONE) { dma_addr_t dev_addr = d40_get_dev_addr(chan, direction); @@ -2007,6 +2081,36 @@ static struct dma_async_tx_descriptor *d40_prep_slave_sg(struct dma_chan *chan, return d40_prep_sg(chan, sgl, sgl, sg_len, direction, dma_flags); } +static struct dma_async_tx_descriptor * +dma40_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t dma_addr, + size_t buf_len, size_t period_len, + enum dma_data_direction direction) +{ + unsigned int periods = buf_len / period_len; + struct dma_async_tx_descriptor *txd; + struct scatterlist *sg; + int i; + + sg = kcalloc(periods + 1, sizeof(struct scatterlist), GFP_KERNEL); + for (i = 0; i < periods; i++) { + sg_dma_address(&sg[i]) = dma_addr; + sg_dma_len(&sg[i]) = period_len; + dma_addr += period_len; + } + + sg[periods].offset = 0; + sg[periods].length = 0; + sg[periods].page_link = + ((unsigned long)sg | 0x01) & ~0x02; + + txd = d40_prep_sg(chan, sg, sg, periods, direction, + DMA_PREP_INTERRUPT); + + kfree(sg); + + return txd; +} + static enum dma_status d40_tx_status(struct dma_chan *chan, dma_cookie_t cookie, struct dma_tx_state *txstate) @@ -2264,6 +2368,9 @@ static void d40_ops_init(struct d40_base *base, struct dma_device *dev) if (dma_has_cap(DMA_SG, dev->cap_mask)) dev->device_prep_dma_sg = d40_prep_memcpy_sg; + if (dma_has_cap(DMA_CYCLIC, dev->cap_mask)) + dev->device_prep_dma_cyclic = dma40_prep_dma_cyclic; + dev->device_alloc_chan_resources = d40_alloc_chan_resources; dev->device_free_chan_resources = d40_free_chan_resources; dev->device_issue_pending = d40_issue_pending; @@ -2282,6 +2389,7 @@ static int __init d40_dmaengine_init(struct d40_base *base, dma_cap_zero(base->dma_slave.cap_mask); dma_cap_set(DMA_SLAVE, base->dma_slave.cap_mask); + dma_cap_set(DMA_CYCLIC, base->dma_slave.cap_mask); d40_ops_init(base, &base->dma_slave); @@ -2316,9 +2424,9 @@ static int __init d40_dmaengine_init(struct d40_base *base, dma_cap_set(DMA_SLAVE, base->dma_both.cap_mask); dma_cap_set(DMA_MEMCPY, base->dma_both.cap_mask); dma_cap_set(DMA_SG, base->dma_both.cap_mask); + dma_cap_set(DMA_CYCLIC, base->dma_slave.cap_mask); d40_ops_init(base, &base->dma_both); - err = dma_async_device_register(&base->dma_both); if (err) { -- cgit v1.2.3