diff options
author | Linus Walleij <linus.walleij@stericsson.com> | 2010-03-04 16:40:30 +0300 |
---|---|---|
committer | Dan Williams <dan.j.williams@intel.com> | 2010-03-25 00:24:44 +0300 |
commit | 84c8447c544bc7579097649273bc3f4e1b5de6af (patch) | |
tree | 7b91a03a61044612d511283e03f545893ba8c464 /drivers/dma | |
parent | cecd87da83869ad4157295b87a2e51e38c3e03bf (diff) | |
download | linux-84c8447c544bc7579097649273bc3f4e1b5de6af.tar.xz |
DMAENGINE: COH 901 318 fix bytesleft
This makes the function to get the number of bytes left in the
ongoing DMA transaction actually work: the old code did not take
neither lli:s nor queued jobs into account. Also fix a missing
spinlock while we're at it.
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/dma')
-rw-r--r-- | drivers/dma/coh901318.c | 96 |
1 files changed, 88 insertions, 8 deletions
diff --git a/drivers/dma/coh901318.c b/drivers/dma/coh901318.c index 20889c98e9b0..f636c4a87c7f 100644 --- a/drivers/dma/coh901318.c +++ b/drivers/dma/coh901318.c @@ -408,25 +408,100 @@ coh901318_first_queued(struct coh901318_chan *cohc) return d; } +static inline u32 coh901318_get_bytes_in_lli(struct coh901318_lli *in_lli) +{ + struct coh901318_lli *lli = in_lli; + u32 bytes = 0; + + while (lli) { + bytes += lli->control & COH901318_CX_CTRL_TC_VALUE_MASK; + lli = lli->virt_link_addr; + } + return bytes; +} + /* - * DMA start/stop controls + * Get the number of bytes left to transfer on this channel, + * it is unwise to call this before stopping the channel for + * absolute measures, but for a rough guess you can still call + * it. */ u32 coh901318_get_bytes_left(struct dma_chan *chan) { - unsigned long flags; - u32 ret; struct coh901318_chan *cohc = to_coh901318_chan(chan); + struct coh901318_desc *cohd; + struct list_head *pos; + unsigned long flags; + u32 left = 0; + int i = 0; spin_lock_irqsave(&cohc->lock, flags); - /* Read transfer count value */ - ret = readl(cohc->base->virtbase + - COH901318_CX_CTRL+COH901318_CX_CTRL_SPACING * - cohc->id) & COH901318_CX_CTRL_TC_VALUE_MASK; + /* + * If there are many queued jobs, we iterate and add the + * size of them all. We take a special look on the first + * job though, since it is probably active. + */ + list_for_each(pos, &cohc->active) { + /* + * The first job in the list will be working on the + * hardware. The job can be stopped but still active, + * so that the transfer counter is somewhere inside + * the buffer. + */ + cohd = list_entry(pos, struct coh901318_desc, node); + + if (i == 0) { + struct coh901318_lli *lli; + dma_addr_t ladd; + + /* Read current transfer count value */ + left = readl(cohc->base->virtbase + + COH901318_CX_CTRL + + COH901318_CX_CTRL_SPACING * cohc->id) & + COH901318_CX_CTRL_TC_VALUE_MASK; + + /* See if the transfer is linked... */ + ladd = readl(cohc->base->virtbase + + COH901318_CX_LNK_ADDR + + COH901318_CX_LNK_ADDR_SPACING * + cohc->id) & + ~COH901318_CX_LNK_LINK_IMMEDIATE; + /* Single transaction */ + if (!ladd) + continue; + + /* + * Linked transaction, follow the lli, find the + * currently processing lli, and proceed to the next + */ + lli = cohd->lli; + while (lli && lli->link_addr != ladd) + lli = lli->virt_link_addr; + + if (lli) + lli = lli->virt_link_addr; + + /* + * Follow remaining lli links around to count the total + * number of bytes left + */ + left += coh901318_get_bytes_in_lli(lli); + } else { + left += coh901318_get_bytes_in_lli(cohd->lli); + } + i++; + } + + /* Also count bytes in the queued jobs */ + list_for_each(pos, &cohc->queue) { + cohd = list_entry(pos, struct coh901318_desc, node); + left += coh901318_get_bytes_in_lli(cohd->lli); + } spin_unlock_irqrestore(&cohc->lock, flags); - return ret; + return left; } EXPORT_SYMBOL(coh901318_get_bytes_left); @@ -831,6 +906,7 @@ static irqreturn_t dma_irq_handler(int irq, void *dev_id) static int coh901318_alloc_chan_resources(struct dma_chan *chan) { struct coh901318_chan *cohc = to_coh901318_chan(chan); + unsigned long flags; dev_vdbg(COHC_2_DEV(cohc), "[%s] DMA channel %d\n", __func__, cohc->id); @@ -838,11 +914,15 @@ static int coh901318_alloc_chan_resources(struct dma_chan *chan) if (chan->client_count > 1) return -EBUSY; + spin_lock_irqsave(&cohc->lock, flags); + coh901318_config(cohc, NULL); cohc->allocated = 1; cohc->completed = chan->cookie = 1; + spin_unlock_irqrestore(&cohc->lock, flags); + return 1; } |